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MG Midget and Sprite Technical - Not starting
| My frog eye wont start.
I thought I would just start her up and run her for a few minutes but it just wont start. The battery turns it over fine, but it just wont catch. There is a spark at the plugs but I don't think its a fuel problem, as I sprayed some quick start in to the carbs and it made no difference - also on removing the first plug, it was wet from petrol. And the strange thing is I did the same thing two or three weeks ago and it ran fine. So think its unlikely the coil, condenser etc would suddenly self destruct, or would they? What do you think the best thing to try next, to try tracking the fault down? Thanks |
| Graham V |
| If its not run regularly I would check the condition of the points (minor corrosion ?) and check points gap still OK ? R. |
| richard b |
| Quick thoughts.
You could try cleaning the plugs and - . tapping the fuel bowl floats . check the choke is fully working . check CB points. There might be a spark at the plugs but is it strong enough. Always have the battery fully charged before looking for an electrical/ignition problem. Have you fitted any new parts recently? Just running the engine for a few minutes isn't a good idea you really need to run all the car's systems by taking it for a reasonable length drive. If that isn't possible then you want to get the engine up to full running temperature and run it for another 5, 10 or better still 15 minutes. ETA: took me so long to type it Richard got there - two for points then, or if you've changed the condenser recently (or even within the last 5-10 years perhaps) check that. |
| Nigel Atkins |
| Have you had the plug leads off? If you have, then double check the firing order. 1-3-4-2 Check for condensation inside the dizzy cap, especially with the cold damp weather we have been having and if you only ran it for a short time on the last occasion - 10 mins is not enough to dry things out properly. Try turning it over after dark and look for stray blue sparks on the HT leads |
| GuyW |
| Gee thanks GUY, A little greedy don't you think, nothing left for the rest of us to O'Pine over Haha But I would have done the same Btw... are the plugs NGK, if so test them for fouling notorious What's the color of the spark Prop |
| 1 Paper |
| Thank you all so much. That's really helpful. That gives me a good idea where to start. In particular in answer to Prop's question, as I recall the spark was red/yellow but from a quick google I believe that indicates the spark is weak and it should be blue? So as soon as I have the time, I will open up the distributor, make sure its nice and dry and check the points. I will report back on how I get on asap Thanks so much |
| Graham V |
| Yes, the spark should be a bright blue/white. I had similar symptoms years ago with a yellow spark... a new condenser fixed the problem, but I later converted to a PerTronix unit and haven't looked back. Bad condensers were all the rage for a while - not sure about the current situation. And while it's tempting to blame the condenser for all ignition problems, it's only one link in the chain. As mentioned above, the points, cap, rotor, and HT leads can also contribute. Best of luck! -:G:- |
| Gryf Ketcherside |
| The contact on the points can get a little crusty if the car sits for very long... so give those a good sanding with a finger nail file Most likely based on your description your looking for corrosion or a bad ground... due to it ran fine and now it wont start and this is in winter with wet weather I think your on the right path if the spark color is in the yellow to Orange range Prop |
| 1 Paper |
| of course, when all else fails there's always Basil's tree... |
| David Cox |
| Hi
Promised I would report back. Following your comments, I had a look inside the distributor (I am a relative novice but learn more and more from experience when things go wrong with the car. So much is still new to me). I have found that I can move the base plate, and I know it is supposed to move with the vacuum advance, but it doesnt spring back. So I can rotate the points assembly by about 30 or 40 degrees and leave it stationery in any position within that movement. I have also spotted a tiny spring hanging near the top of the base plate which I assume should be attached to the base plate. So I will take the distributor out to take a better look. Its all pretty tight down there, just hope I don't need to remove the steering column to get it out. I'm also wondering if it would be sensible to buy petronix or something similar to save messing about with points and a condenser. Graham |
| Graham V |
| Odd then, that it ran before without problems and that the spring has now spontaneously detached itself since you used it last? Sure you didn't just knock the spring whilst drying the parts.
If you are removing the distributor, then mark it accurately with paint or tippex marks on the edge of the dizzy with a corresponding one on the clamp or block so that you can get it back in the same position. You may still need to re-time it to be accurate, but it will at least be close enough to get it started and running properly. Whilst you are about it, number the plug leads with paint marks as well, 1 - 4 If you remove the contact breaker set, make a very careful observation of the sequence of assembly of insulators and washers on the fixing post. It is very easy to reassemble them wrongly in which case you will get no spark at all! |
| GuyW |
| Hi Guy Thanks for the comments. It does seem odd that the spring has come off. I am fairly certain I didn't do it. The thing I don't understand is how the spring operates. I attach a photo and you can see the free end of the spring on the left. I assume that the lug to the right is what it should be attached to? But what confuses me is that the base plate turns clockwise from this position - see next posting with second picture 
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| Graham V |
| Heres the second picture - how does the spring let the base plate turn clockwise? Hmmmmm? 
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| Graham V |
| hi Graham. The springs control the advance of the timing. You'll find two springs under the base plate, one made of heavier guage wire than the other. The lighter one allows rapid advance at "lower" revs then the heavier one takes over. This gives an advance "curve" with a kink in it but it gives the necessary control. I run mine with points and a condenser but then I was never one to embrace new ideas.... If these are properly maintained you should have no trouble. |
| David Cox |
| What Guy has said.
Mark everything up and take photos or notes of how it is at all stages. I'd also mark up the dissy cap if you're going to remove the HT leads from the cap. It's a good idea to have the HT leads permantly marked up as even the most experienced can mix them up, I use very small cable-ties so the won't fall or get rubbed or knocked off. I'd put two separate marks on the dissy to clamp/engine because if you only put one and you change your viewing angle slightly you might put the dissy back slightly out. Also when you put the dissy back in hold the rotor arm as it slots back in so that it doesn't slightly move as well, each slight movement could add up. I don't know about Pertronix but I much prefer a good quality igniter head but that only deals with the top end of the dissy leaving the bottom end worn. Personally I'd go for fully electronic dissy for fit and forget like 123 or CSI. The CB post sequence Guy mentioned is detailed and drawn in the Driver's Handbook (such a useful publication) edited extract below. ETA: this post is still relevant but I now need to catch up, I'll see if I can find some more info.i 
|
| Nigel Atkins |
| Graeme, the "spring" you are loking at isn't a spring in the normal interpretation of a streatchy device. What that thing is, is the attachment from the vacuum advance diaphragm. Its tightly coiled like that to provide a degree of flexibility as the dizzy base plate turns. And yes, it should be attached to that peg on the base plate and it will stop it from flapping around once you have reconnected it.
There are two small springs further down in the mechanism that control the centrifugal effect of advance for the ignition timing. These may well still be connected and not need to be disturbed. I would just reconnect the vacuum link and try it again. The less you disturb, the less likely you are to upset something which is perfectly OK! Its the basic rule of fault finding: Only change one thing at a time, then retest! If you change lots of things you won't know what has improoved it, or worse, what has created additional faults! |
| GuyW |
| In your photos it looks like it's the vacuum advance spring (rather than the cam springs that sit below the plate) that's adrift. Once again Guy has got there well before me, I was just off looking to see where exactly it hooks up to. |
| Nigel Atkins |
| My mind is even slower than usual at the moment, should have thought of Paul's site mgb-stuff straight off. On link is a photo showing spring attachement - http://www.mgb-stuff.org.uk/vacadv.htm |
| Nigel Atkins |
Photo from Paul Hunt's site mgb-stuff.org which deserves support, lots of info cross over to Spridgets from MGB.
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| Nigel Atkins |
| Another small point, using the correct size of tool, I'm not suggesting it was you that done it but the screw head in the photo is knarled if it continues even the correct tool will be difficult to use on it. |
| Nigel Atkins |
| LOL Nigel! I wasn't "well ahead" of you Look at the message posting times. Dead heat?
The other thing Graeme. Its hard to tell what is shaddow, but given that the heel of the contact breaker is pretty well onto one of the lobes of the cam, I would expect the points to be wider open than that. They are also badly corroded. Clean them as Prop said, and carefully reset the gap. I don't know if you have already removed the dizzy, but I wouldn't disturb it at all at this stage. Its easy enough to do these basic tasks with the dizzy still fitted in the car, and there is less to go wrong that way! |
| GuyW |
| David, Nigel, Guy
Thank you so much, for your help. Tomorrow I should have time to clean and set the points, and slip that spring back on. Can I ask a couple of questions please? With the spring replaced on the lug, will the base plate be able to turn clockwise, as that's really the only way it can turn, as you will see from my two photos. Assuming of course that "clockwise" is where it is supposed to go. I guess I will see when I put the spring on, but just interested Also I was looking up spare parts, and also looking at electronic systems- my distributor is marked DM2. Is that the same for all intents and purposes as the 25D? I already have the distributor out but I should be able to set the timing with a light bulb and then adjust it with my strobe once it, hopefully, starts. Nigel, that horrid looking screw was not my handiwork! Thanks again Graham |
| Graham V |
| Graham
As Guy mentioned earlier, the 'spring' is actually the connector between the vac diaphram and the points plate. Not all dizzies have a spring some have a rod or a plate arangment--all do the same job- With the spring refitted to it's post on the plate it should work normally Normal operation is- Apply vac. to the diaphram, the diaphram will move and pull the connector (spring) which will in turn pull the points plate around - clockwise----When the vac is released the return spring (not visible) inside the vac. pot will return the plate anticlockwise back to it's base position Cheers willy |
| William Revit |
| There are also 2 small springs in the base of the dizzy. They don't act directly on the base plate but control the movement of the two centrifugal weights, which in turn advance the timing. But as they don't act directly on the base plate you won't feel their effect by trying to rotate the baseplate |
| GuyW |
| Graham,
once you've cleaned and refitted your points you want to check the gap again after a little use and perhaps again after a bit more use to make sure they're secure and not closing up. DM2 isn't the same exactly as 25D so parts will vary a little, as far as igniter heads, see below for info only not recommendation as I've never had them- https://blog.simonbbc.com/faq-helper-page/quick-look-at-the-powerspark-ignition-kit-k2-lucas-23d4-25d4-4-cylinder/ http://www.simonbbc.com/electronic_ignition_kits/by_distributor_model/powerspark_electronic_ignition_kit_for_lucas_dm2_distributor http://www.accuspark.co.uk/distributor_idinfo.html http://www.accuspark.co.uk/kit_search.html |
| Nigel Atkins |
| Guy, I hadn't noticed the times of our posts, yours was there when I posted. I'm not sure how the timing works as usually I'm editing a post for 5 minutes and over, I guess it's at original posting before edits. I wasn't sure where the vacuum spring hooked up to so was looking elsewhere. |
| Nigel Atkins |
| Just for clarity
The base plate does not spin, it moves back and forth but not by very much If you marked the dizzy and the engine block, you won't need to dynamic time the egnition ... all that does is put the dissy in the approximate location so you can finish timing the ignition If you don't already have a timing gun.... then you need to get one, you can't properly time it by ear or by sight A few notes You will need an assistant to rotate the sissy because the timing marks are on the bottom of the front timing chain cover... This can be very dangerous ... find the timing teeth 1st before you start the can, block the wheels and make sure the car wont move There is a good chance you will have to Jack the car up at the front to crawl under it head 1st with the engine running Make sure your assistant isn't an idiot, and wont horse around Make sure to plug the rubber hose from the dissy to the carb so air won't enter into the carb...crutial) The points defiantly need cleaning up, but I'd try to clean them in place and adjust them with the sissy out ... If you don't get the points assembly correct it wont fire... and the parts are confusing the 1st time ... everyone screws it up, so pay close attention to the diagram on points assembly that Nigel posted The loose spring didn't stop the engine from starting Make sure the rubbing block that the points are rides on is clean and shiney, if it's rusty or pitted it will eat the points arm up fast Agian... MAKE SURE YOU HAVE A STROBE TIMING GUN, Please don't tell us you timed it and 200 post later you flipantly say you timed it by ear These guns can be purchased inexpensively ... it's a necessity, not a good suggestion Last if your going to go with electronic ignition DO NOT USE pretronix... they used to be good but China ruined them, USE the kit known as Simon BBC, as far as I know it's better quality and a fraction of the price and more local to you Good luck, keep us posted (TIMING GUN, TIMING GUN, TIMING GUN ) PROP |
| 1 Paper |
| Thanks for the helpful posts.
I cleaned the points up, reset them and put everything back. Please dont shout at me but I hadn't marked the distributor position beforehand, I took it out before your warnings. But I put it back in about the same place, and very luckily, the engine fired up first time. What a lovely sound! The reason I didn't set the static timing was because there are no timing marks on the pulley, so think I was very lucky to get it running. Its not the original pulley. But the markers attached to the block for TDC, 5 degrees and 10 degree are there ok. I put a pencil in cylinder 1, to find what I think is TDC and have put a paint mark on the flywheel. Prop, I do have a timing gun, but couldn't use as I needed to let the paint to dry. Does that all sound right? On a very quick drive I found the engine struggled under load, which I assume is the timing. The plugs looked very black, but I think I should leave the carbs until after the timing is sorted. |
| Graham V |
| Graham,
well done you've got it started. A quick drive with choke could be contributing to the plugs being black, a longer drive with a blow out run when fully warmed would have been better (subject to engine not struggling on level and downhills). Struggling might be timing but it might not or only be a contributing factor like the plugs colour. Also you said your plugs were wet from when it didn't start so that may or may not be involved. Do, and if required test, one thing at a time. Set up - tappets - CB points – plugs - timing - carb mixture in that order, if you have to adjust any item in that chain then you’ll also need to check/adjust all the items that follow it in the chain. I'd suggest you start by checking tappets clearance, recheck points, clean and check gap on plugs, all before moving on to setting the timing and then check and if necessary adjust the carbs last. All necessary info is in the Driver's Handbook of course. You've not said how starting and tickover was, if both were good then you've got the items back in the correct order but always worth double-checking as in doing so you might spot something else that might be a or the cause of your problem. |
| Nigel Atkins |
| Thanks Nigel.
In answer to your question, it started very easily, and idled relatively well, considering it was cold. But under load, i.e. going up the hill outside my driveway, it didn't sound right. I would be very surprised if the timing is right, as the distributor position was a guess. I should have taken a photo (slap hand and remember to do so next time), but it seems the cap for the HT lead from coil on to top of the distributor is very near the steering column, only a matter of a couple of mms. Could anyone with a frogeye (or knows the setup) tell me how theirs compares to my setup in the photo attached please? - (I have zoomed right in - the column is on the left) Thanks 
|
| Graham V |
| Paint ? What paint was drying?.... okay as long as you set the timing
Agian the car ran fine up until recently sand now we now it was the points where corroded and probably a little off There is no need to mess with the carbs... you found the problem it was the points, it's running, get it timed in and your fine once agian. There is no need to fix what isn't broken... carbs don't accedentilay fall out of tune, so I wouldn't touch them. What pulley does it have and how do are you aware of this, what is the pully from. Prop |
| 1 Paper |
| I think I may have found the answer to the second paragraph of my last posting. It seems that the distributor originally had a cap with side entry cables, part number GDC102. That would avoid possible fouling with the steering column. It takes screw in leads, whereas mine (which I assume is GDC103) has top entry leads which plug in. Mine appears to have superceded the one with side entry. In most cars, I guess the fact the leads are top entry doesnt cause a problem. |
| Graham V |
| Graham Yes, you should have the side entry cap, ideally. |
| Dave O'Neill 2 |
| Graham,
You are correct in that they came with side entry leads. But, how long has that cap been on the car? If it ran well before this problem came up, I wouldn't worry about it right now. I'd try to get the timing right to start and maybe change the cap later. To see if the closeness of the column is causing a problem, start the car at night and with no lights on see if there is any spark arcing there. I've had both types on my car but it's a left hand drive so I don't have the clearance problem. Dave posted while I was typing ;-) |
| Martin |
| Graham,
timing could well be out but also check you have the HT leads on correctly and in correct order.. HT leads – check they are firmly seated at both ends, wipe them over with a clean rag then look at their condition, are they brittle, pinched or scuffed if so replace with a new set. The rotor arm runs anti-clockwise so the leads should be positioned on the dissy cap with 1 (that goes to the cylinder at the front of the car), then anti-clockwise on the dissy cap goes 3, then anti-clockwise 4, and last anti-clockwise 2. 
|
| Nigel Atkins |
| good point re HT leads but watch that the new set doesn't have too high a resistance or they will draw a high current and the problem will move to burned out coil |
| David Cox |
| Sorry David, have to disagree here - higher resistance HT leads could only lead to a lower current draw on the secondary of the coil (ohm's law) and thus a lower current draw on the primary. |
| Simon Wood |
| yes Simon,,got the equation wrong! Back to Physics lessons for me... |
| David Cox |
| Just wanted to say thanks to you all for your help and support. Some really good advice, thanks.
Spent today trying to get the timing sorted which was much more tiresome than it should be. As I said, there was no timing mark on crankshaft pulley so had to find TDC. I went over my work yesterday and think I have it more precise now. For dynamic timing, strangely my Haynes manual just says "not specified" so I only had the static 5d before TDC to work with, and then my gun stopped working! Anyway, I have road tested it and it runs nicely thanks to you guys, no pinking and no backfiring, so could be worse! Graham |
| Graham V |
| Well done Graham.
The Haynes is best used as a repairs reference after first consulting the Driver's Handbook. Note all publications have errors and omissions but I find (a lot) more so with Haynes than factory publications. Buying a paper copy is a very good investment - http://brooklandsbooks.co.uk/index.php?route=product/product&path=12_35_526&product_id=62 or (the option of two) free downloads here - http://www.spridgetguru.com/TchIndx20.html I'd suggest you now fill it with good quality petrol and take it for a good longish blow out run on twisty roads with gradients to fully test it, and enjoy it. |
| Nigel Atkins |
| So are we to assume you tried to use a timing gun and it couldn't work so you timed the engine by sound and feel instead of using the perfection of the timing gun?
Someone has to teach me how to blink my eyes fast enough or to hear what 10 degrees at 1000 rpm sounds and looks like Did I mention the word timing gun? I don't know, I don't get it. Heads up... you cant fix holes Inn the top of piston with jb weld and masking tape dosnt cure chewed up bearing shells from an over advanced engine.... but maybe that's just me. Dim. Prop |
| 1 Paper |
| Prop No I got the 5 degrees before TDC at idle with my timing gun, before it became very intermittent - I know its sort of supposed to intermittent, but I'm sure you know what I mean! Graham |
| Graham V |
| Okay, now I understand where your at. So the timing marks are moving around when you shine the gun strobe on them? error the pully Mark? Did you plug the hose to the carb from the dissy advance so air can not be sucked into the carb... that will certainly contrcontribute to a bouncing timing marks But regardless she is running good agian ? Well done Prop |
| 1 Paper |
| Yes thanks she is running very nicely now. Strangely though, on looking at the plugs, it look like its running rich on one side but on the other half (actually probably about third) of the plug, it looks a much more healthy colour. I've attached a picture but not that clear I'm afraid. I did clean them up well beforehand, and it ran nicely. Thats on all 4 cylinders. What could cause that do you think? 
|
| Graham V |
| Graham,
a couple of assumptions first, if these assumptions aren't correct then they need sorting first - . you've got the correct grade of plugs installed for your engine . you've check (or rechecked as required) and adjusted as required - tappets, CB points (again), (plugs), timing and carb mixture, all in that order. Allowing for above the usual suspects would be - . (carb mixture too rich) . too much choke (or use of) . too much idling . too much driving at low speeds . dirty or restricted air filters (especially if oil bath type filters) . permutation or combination of any of above. |
| Nigel Atkins |
| ETA: The only thing I can think of for the clean third is perhaps you'd just started to blow them clean on your run but didn't sustain it for long enough - but I might be totally wrong as I know nothing actually about engines and tuning. |
| Nigel Atkins |
| Nigel
Thanks for your comments. They have made me think which is a rare thing these days! I am intrigued and concerned about the uneven pattern on the plugs, and dont understand (probably through my own lack of experience) how items such as tuning, filters etc would have that sort of uneven effect. Thinking out loud, I was wondering if it would be something to do with the physical "layout" of the cylinders that would cause it. So still thinking out loud, if the valve clearances were wrong (and of course I know you have already mentioned to check them), then maybe that could influence the "pattern" on the plugs, through the valves being open at slightly the wrong time. When I sorted out the points and timing, I went for a test drive, and looked at the plugs afterwards. They were black all over indicating the mixture was too rich, so I leaned them off 3 flats. Then I went for another drive, and although was very happy with how it ran, the plugs were as shown in the picture in my previous posting. If my tappet theory is correct, it was probably so rich before, that the richness saturated the tappet error. So as soon as I get an hour or so spare, I will check the tappets (which I know I should have done already) and report back |
| Graham V |
| Graham,
I don’t want to be the visually-impaired leading the way here my thoughts on the setting of the tappets was for the possible engine timing issue. If the tappets are maladjusted then this will have effect on the timing. As they‘re at the start of the chain they effect the rest of the chain to get the right conclusion. Normally if they’re checked and set reasonable well then other than wear or work on the head perhaps an annual check is all that’s required. The tuning, running, filters, etc. was in reference to the “sooty” plugs rather than the pattern. I’m not sure what way you’re adjusting your mixture and setting up the carbs so will leave that for now (hoping someone who knows what they’re talking about jumps in). If when you check the tappets they need adjusting (other than minor adjustments perhaps) you’ll also need to check and adjust as required points, (plugs), timing and then mixture. Is your engine standard 948cc? What tappets gap? What points gap? What plugs and gap? What type of air filters and are they clean and unobstructed? |
| Nigel Atkins |
| Nigel Yes its a stock 948cc engine on a 1959 frogeye. I have been looking up the tappet spec, and am confused. The Haynes manual says 0.012 inches, but doesnt say if thats when hot or cold. The factory manual also 0.012 inches. Problem is at the front under spec it says 0.012 cold, but under the detailed instructions it says set while hot! |
| Graham V |
| I'd move the carb flats back to orginal... it rqn good before so thwt takes carbs out of the equation
I couldnt see the plugs to well in the photo but if there rich I'd add to novels comment To much started spray was used earlier getting it to start And your inbthe north east where the winter has been really cold, so fuel is more cold then normal and that means it was ont atomized as easily with the air and that will make the fuel charge a little more rich At this points do a complete tune up as Nigel suggested Makebsure The fuel is fresh less then 3 months old, adjust the valve lash using rule of 9 ( set them cold) if they get noisy after there warm then adjust agian And just follow The order that Nigel has laid out... try AutoZone for a Haynes manual they can get them over night cheaper then moss or Vic Brit and a good manual to have ... there are better over seas but Haynes will do the job A tip.. I use a Sharpe marker and color one flat on the carb adjuster nut as a reference so I can count how many full turns I've made .... Trust me the mind does wonder at the oddest moments... is That 3 flats or 5 Also I put the car in 4th gear and grab it by the front bumper and pull it and watch the valves move to set them up... coil disconnected of course |
| 1 Paper |
| Thanks for the tips Prop. I will report back in due course. And good idea about marking the flats. I will use that for sure G |
| Graham V |
| Graham, from Austin-Sprite Driver's Handbook 97H 1583B "Valve Clearance (hot or cold) .012 in. (.305 mm.)". http://www.spridgetguru.com/DriversHandbooks/97H1583B.pdf So even more confusion, I also seen elsewhere 0.012" cold for all Spridgets. If you want to be sure you could put up a new thread asking what others would set a standard 948cc Sprite to. You could also put up a new thread for the plug soot pattern. |
| Nigel Atkins |
| Prop, why disconnect the coil? |
| Nigel Atkins |
| Now have access to books and PDFs, both my Haynes (1974 and 1982) in the text have setting cold. From (1972) Workshop Manual for 948cc – “Valve rocker clearance: Running (cold) .012 in. (.305 mm.)”. |
| Nigel Atkins |
| I was trying to work out what was on the left of the spark plug in the last photo. I've come to the conclusion it's an upside-down egg box. Anyone remember 'Ask The Family', where they had to identify everyday objects, photographed from a peculiar angle? |
| Dave O'Neill 2 |
| Nigel...
To avoid the risk of accidental starting while in gear! , provided your like me and put the key in and move it to the on position in order to free up the steering wheel lock. So the wheels can be corrected while pulling the car by the front bumper while watching the valve action. Probably little over kill on the safety front esp for someone like me that's not very safety conscious to begin with.... but I do have my moments I didn't realise this engine is not a 1275, and is infact a 948 So I can not advise on the valve lash gap as its gap size nor its setting in cold or hot All I can provide is general basic automotive tech P |
| 1 Paper |
| Now you've put it I can see it before I thought it was some bit of rubber tread, well I only quickly looked and was concentrating on the plug in the vice hoping it wasn't held by the insulator. Ask the Family, you're so middle-classed. Even in the '70s the families looked like they were from the '50s, at least from my council estate perspective. |
| Nigel Atkins |
| Prop, yes I was very surprised at your uncharacteristic caution. As such, I once twigged my back pulling the Midget forward by the front bumper bar whilst in 4th on my flat concrete hardstanding - ignoring health & safety is mad. |
| Nigel Atkins |
| Graham - my MkI Workshop Manual 1960 says, "between the rocker arm and the valve stem there must be a clearance of .012in for both inlet and exhaust, clearance being set with the engine hot." |
| Nick and Cherry Scoop |
| Nigel ... you screwed up your back?
That sucks... was it the up state up bringing you mentioned ... haha Nah... I'm sorry I shouldn't have said that...BUT that said you do have to exercise caution the older we get, that's a good way to end up in bed for 3 months, you really want to pull with the arms not the back I always like to get low so my arms are parallel to the ground while pulling from the bumper and that takes alot allot of strain off the upper body as it makes the legs do the actual work... so good grippy shoes are crucial Another advantage is you can spin the engine if need be from the solenoid with a jumper wire and no fire going to the plugs |
| 1 Paper |
| Prop, it was a mere twinge, all sorted with a midnight outdoor shower in the hail, sleet and snow that night, all part of the ol' skool projects upbringing. |
| Nigel Atkins |
| Thanks for the postings and it is concerning that different publications including the factory manual give conflicting specifications.
I've checked and they are all correct at 0.012 inches cold (assuming cold is correct). Much more importantly, Dave you are correct, it is an egg box! It was a useful tip I was given a very long time ago. When dismantling things, the screws, bolts, washers etc, are temporarily stored in order in consecutive sections of the egg box, meaning I dont loose anything and I know what order to put them all back. Sometimes, I will write on it too, to identify what goes where. Graham |
| Graham V |
| Graham,
on top of the posts from me and others below I'm still wondering about which spark plugs you have fitted and the gap set? I was also thinking for any meaningful road test you do need the engine fully warmed up especially this time of year so perhaps it might be an idea to partially or fully warm the engine before starting the road test. I also wonder what temperature your engine gets to when fully warmed and running on the open road at this time of year and when compared to a 70c spring/summer day? ETA: I was typing whilst you posted |
| Nigel Atkins |
| I wouldn't set them cold. How long is a valve stem? Three and a half, four inches of linear expansion potential. I don't know that sort of science, but somebody will know how much the gap will close as the temperature goes up. I like to hear my rockers just a bit: a chatty tappet is a happy tappet, didn't someone say? |
| Nick and Cherry Scoop |
| I must say l have always set them cold, but then l use 16 thou. as that is what Kent Cams advised. On my 1500 I did them 12 thou, hot, and with the engine running. The calculations would be fiendishly complex with valves, push rods and cam followers all reducing clearance as they warm up. And presumably block and head having the opposite effect. |
| GuyW |
| to hear my rockers just a bit: a chatty tappet is a happy tappet, didn't someone say? Yepp, Trevor Jessie back in the day coined the phrase " noise valves are happy valves " On my 1275, I adjust them to .016 , then adjusted manually 2 That were really noise hot with the engine running ....( and it wasn't much,) and that has worked out well |
| 1 Paper |
| Adjusted down another two flats and the plugs look text book colour - thanks for all the help. Just the brake fluid mystery to solve! Graham |
| Graham V |
| Graham, well done and thanks for reporting back. Does that mean you're one flat away from your original starting point (or five?). A 3 or 4 mile test run this time of year could leave you with black plugs that could be blown off on a warmer run. As long as it's repeatable you've possibly sorted it, certainly you've progressed well from a car that wouldn't start. More driving and a full service will help to get it and keep it running well. Cheers. |
| Nigel Atkins |
| Yes sorry, I should have said adjusted up another two flats - so yes five in total. Of course I have adjusted the timing and points too. The tappets and plug gaps were fine. Its running better than before, so I am well pleased with it. Thanks for the tip, I will check them again when the weather is warmer |
| Graham V |
| Graham, well done on getting it running better. Five is a lot, but you have adjusted your timing, you're probably find starting a little different and possibly use a little less fuel. What spark plugs are you running and what gap? What type of air filters? A good full service will also help and help to keep or improve performance and reliability and might find the fluid leak. |
| Nigel Atkins |
| Hi Nigel My plugs are NGK BPR6ES - not sure what the "R" means and I doubt they are listed as the recommended plugs - but they seems to work ok! They are set to 0.025" |
| Graham V |
| Graham, My bet is that the "R" means resistor. I believe I have heard that problems can be caused if you run resistor plugs with resistor wires. That is, one or the other is okay, but both is too much resistance. Someone else may confirm or deny? Charley |
| C R Huff |
| Y yes, Charlie is correct R = resistance Most likely these are going to foul out fairly soon ... if for no other reason they are NGK.. I used to he a fan of NGK, But not so much they are sensitive to fouling... The last set I had 1 that was bad out of the box I'm using a set now called danso? And no problem there and of course champion is still a good plug I've got them in my work truck But if you have similar issues down the road I'd lean towards the ngk plugs |
| 1 Paper |
| Hi Graham,
you don't need the R ones, not even with a fully electronic dissy as I did, more money for no gain, I lived and learnt just for once. I wondered if you might have the 5 but if the 6 (or 5 had it been them) are working well then stick with them. I tried the BP6E last time as they were only £1 each and didn't notice any difference but will be putting BP6ES in again soon just to see if makes any odds and I think it's best to replace plugs before they go passed their best rather than after. I've never had any trouble with NGK but did have a Champion plug split early in its use. (Dentist fashion) What type of air filters are fitted to the car? |
| Nigel Atkins |
This thread was discussed between 05/02/2018 and 17/02/2018
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