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MG MGB Technical - Difficulty in turning crank by hand

My thread "Batteries - smart charging/replacement" seems to be a misleading title now, so hence the new thread.
Recap: 1963 Mk1 - first run after restoration in late 2012. On road from Jan2013.
Difficulty starting after 3 month idle period. Determined battery kaput so replaced it.
Then chasing ignition spark issues - deduced that coil, distrib, leads and plugs actually OK.
Then checked choke adjustment - virtually no movement of jets on full choke.
So I adjusted choke so that at full choke get about "5/16"(8mm) lowering of jets.
Engine still didn't start - same symptom - starter engaging then disengaging.
Before continuing (and pre-empting suggestions) I thought I would double check the timing as I had pulled the distributor out to replace the condenser.
This is where things got more worrying. I tried rotating the engine with socket on the crank pulley - but I couldn't get it to move. Tried engaging the gears and pushing the car (all plugs out BTW) but it feels locked solid. Put it in 4th and started getting some movement.
Then I tried cranking (fully charged battery) - turned over but with a metallic squeal.
Removed fanbelt to eliminate water pump - pushed again and sound definitely from engine - from within cylinders. Tried adding a bit of lubricant and cranked - seemed OK

Long saga, but is this just a symptom of lots of cranking with no starting, and little oil getting to pistons? It seems that the oil flow path leaves the cylinder walls till nearly last, and only thrown up by the rotating crank and the conrods. So not a major concern for me before I get back to the timing and then further starting attempts?
John
John Minchin

With a lot of non-starting cranking in short bursts you will be losing oil from the bearings but not developing oil pressure to replace it. It wouldn't have occurred to me before, but from time to time you probably should be taking the plugs out and cranking to get full oil pressure, before trying starting again. However a locked or nearly so engine is worrying.

Another thing that has just occurred to me that dates back well over 40 years. A bypass was being built round my village so was a magnet with all the machinery being used. One of these was a tractor that the 'ignition' and starter switch had been damaged on so they used to start it with a box spanner bridging the two solenoid terminals. Needless to say when work had finished I used the same trick and spent many a happy evening charging up and down the road as it progressed from grass through dirt to tarmac. The points of all this is, that because the ignition switch was damaged, and it was a diesel, they couldn't use the glow-plugs to pre-heat the cylinders. The effect of that when bridging the solenoid was one cough and it threw out the pinion, and one had to repeat that over and over again until the cylinders got warm enough to catch properly and run. Just a thought.

Also that being a 63 and so an inertia starter as above maybe that is the problem i.e. being thrown out too easily.
Paul Hunt

No - oil is squirted up the bores from a drilling on the big ends and should be effective as soon as oil pressure is registered on the gauge.

Sounds like the engine is partially seized, possibly from the rings corroding to the bores.

Drop some diesel into the spark plug holes and leave for a couple of days, then some oil and leave for 2 more days before cranking the engine over without the plugs in - you may want to consider towing the car in 4th gear rather than use the starter!

Once the engine is free to turn then start it and run it up to full temperature and then do a compression test to see if you have any loss of compression due to stuck rings.
Chris at Octarine Services

"run it up to full temperature"

Ooooohh, that he could!
Paul Hunt

When cranking the other day, I noted that the pressure was showing as about 25psi on the gauge.
Chris, how could the rings corrode onto the bores? Car was running fine before a period of inactivity - then non starting. But all the time, when attempting start the engine turned over. So oil should have been getting to the bores.
During restoration, the engine was not run for 12 years - small quantities of oil were squirted in every so often and the engine turned over by hand. Then on when the time finally came it started almost at first go.
So I am struggling with the idea of partial seizure after a small amount of inactivity apart from cranking.

Surely these engines are not that frail?

Paul, I've had some other ideas about getting the engine up to temperature, but they are not terribly sensible!!

John
John Minchin

John,
did you turn the engine with the dizzi removed? If yes, the drive might have jumped out and is blocking the crank now.
Siggi
GHD5

The fact that the engine is difficult to turn over makes me think that the starter motor pinion might be jammed into the flywheel ring gear teeth. The early starters were notorious for this and it's why I converted my '67 B over to the later '68 and newer pre-engaged starter. The early starters can be backed off from the flywheel ring gear teeth by removing the cap, on the front of the starter, and turning the armature shaft with a spanner to free up the pinion from the ring gear. RAY
rjm RAY

If the last run before the period of inactivity was short and the engine did not reach temp then it is possible that there was condensation in the bores - also engines always have at least 2 valves open so condensation can get in if the air is moist.

Ray's suggestion is also worth checking - the squeal could be the starter motor ...
Chris at Octarine Services

Siggi - checked distributor when I reinstalled it. Engine hadn't been moved, so should be OK
Ray - Starter is definitely free.
Chris - couple of squirts of oil yesterday - turned over by hand this morning - squeal reduced and although still a bit tight, I could turn the crank by hand with normal socket drive (ie no extension to handle!)

I'm wondering if cranking with no start has introduced unburnt fuel which has "cleaned" the cylinder walls of oil and when left a day or so, this might be why the rings stuck.
I'll try your suggestion of soaking for a couple of days , then cranking.

If this all seems to be taking forever, its because I'm very cautious. Eliminating potential issues before I move on

Thanks for the advice.
I'll report back in due course
John Minchin

Back sooner than I expected.

I put some oil in the cylinders, cranked with a fully charged battery. Turned over easily, no squealing. When I took my finger off the start knob the engine spun over freely a couple of times and stopped. Seemed quite free.
Adjusted the static timing - it was OK.
Plugs in - another crank - nice and free.
Leads on, choke set - 1st turn of the key cough splutter. Second turn cough Brrrmmmmm!
I let it sit at fast idle for 1/2 hr until up to temp - slowly reducing choke. Oil Pressure about 55-60 psi dropping to 50 at normal idle.
No nasty sounds, smells or leaks.
Am I happy or what?

Thanks to all for advice and support.

I will remember to give it a regular run in the winter months - we do get some clear but cold days so I've got no excuse now.

John
John Minchin

Good news, but still no indication of why the starter kept getting thrown out.
Paul Hunt

Paul,

You've answered your own question in an earlier post!

"Also that being a 63 and so an inertia starter as above maybe that is the problem i.e. being thrown out too easily."

If you've ever had a starter motor with a sticky bendix, you'll know that the starter needs to be thrown out easily!

Mike
Mike Standring

I said "too easily".
Paul Hunt

This thread was discussed between 07/10/2013 and 09/10/2013

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