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Triumph TR6 - Mixture Adjustment

Hello,
When I rebuilt the carbs on my 75 TR6 I noticed that on one carb when I turn the allen key cw till it stopped it then took 2 complete turns ccw before the needle / carrier becomes flush with the air valve. On the other carb the same steps took 4 turns ?? Is there something I"ve missed rebuilding these ?. I'm having trouble with my mixture being too rich and it's hard to adjust the carbs equally when the turns on the screws are not the same. I figured out how to maintain the same ratio but I feel something is wrong.
When I adjust them both to be flush and then install them I still have a rough idle..I have a vacuum leak I'm trying to find as it sits around 15 and the needle on the gauge is steady.
Thanks Charlie
Charlie

Hi Charlie. Perhaps the hex screw/retaining washer is not fully seated in the rod? Run on old valve stem or similar tool down the rod to make sure. You shouldn't have this much "misadjustment".

Rick O.
Rick Orthen

Hi Rick, Thanks for pointing me in the right direction. I took apart the offending mixture valve and found the retaining clip has one missing tooth on it and it allowed the screw to move up and down slightly which explains why it would run so rich sometimes. When I replaced it both adjustments are about 2 to 3 turns equally.
Thanks again
Charlie
Charlie

To all
While on this subject...when engine is off I can move the air valve up slightly before I fell resistance to the damper (oil). One carb seems to have slightly more "free play" than the other. The play is less than 1/8". I pulled both dampers and are identical. About 1/8" gap between bushing and retaining ring....(same left/right movement of the bushing on the damper shaft). This is the "free play" I presume I am feeling. Damper oil level is OK. Is this normal? Has anyone installed another washer to reduse this free play? Maybe this is a case of"Rick, ignore it..not a problem".
Off to Seattle next week to see 2 fine examples of TR6s and enjoy a few suds with fellow enthusiasts.
Rick C
Rick Crawford

Hi Rick,
I noticed the exact same thing with my carbs, I guess that's normal. Both have been rebuilt and it still does it.
Charlie
Charlie

Charlie;
Another check to consider.
There should be an archive regarding valve adjustment we discussed a few months back. To recount, I had trouble developing vacuum after a rebuild, only about 10-12in., would not idle at all. Re-adjusted valves three times per TR manual, removed intake manifold,replaced gasket etc. with same results. I finally re-adjusted valves by bringing each piston to tdc, and adjusted the valves for that respective cylinder. It then developed 20in vacuum, and idled nice. Seems a few others have experienced this problem as well.
Just a thought.

Pete Haburt
Pete Haburt

Thanks Peter,
I adjusted my valves a few weeks ago using that method. I just removed my EGR valve ( and discovered the diaphragm was shot) so I capped the holes, I'm positive when I get the new retaining clips for the air valves in the mail any day now she'll run a lot better
Charlie
CHARLIE

Going to pick up the GUNSEN clikadjust, colour tune, and the carb sync tools from Jeff Zorn while passing through motor city in one week. Has anyone used the clikadjust tool? If so what is number of "Cliks"? or does anyone know TPI count on the valve adjusting screw? Will let u know what I think of the clikadjust and colour tune tools.
Rick C
Rick Crawford

Rick, I happened on a company selling clikadjust on the web. Auto Expert Products from Florida. On there site they had a 2 page instrution sheet on it's use, I wish I had checked it out sooner as I spent $59.95 at Moss, and they are $39.95/ you will also need a 6 point 1/2 inch drive by 1/2 inch socket to make it work.
www.aep.bigstep.com/clik.htm
KBD Dixon

Mr. Dixon- Very usefull information ,BUT, lets get to the crux of the matter . DID IT WORK? And how many clicks?
Don K.
DON KELLY

Don, Yes it is a very worthwhile addition to the toolbox. The # of clicks seems to be 2 however with such a small amount of gap .010 inch I am still checking with a feeler guage after each adjustment. I will continue to post my impressions and maybe others can join if they are using it also. maybe a new thread.
Regards, Keith
rainy and 45 degrees here
KBD Dixon

I have been playing with the fuel mix on my Strombergs (the car seems to be running lean), and surprisingly the rear mix adjustment turns more easily than the front. (Yes, I have that funky tool.) Is this normal or indicative of some problem? Could this be another symptom of Charlie's original question? I will check to see how many turns I get in each when I get home later.

The rear carb was also 2.5 turns out/lean from full rich, while the front was only about 1.5 turns out/lean. The carbs should be even, right? Is there a "typical" number of turns out that the carbs should be or does it simply depend on the carbs? Right now, I am at almost full rich (i.e. 0.75 turns CCW from full rich).

Ignatius
Ignatius Rigor

Hi Ignatius,
It sounds like you have the same as me...If you take the air valve completely apart you'll find that the number of turns from one direction to the other will be the same. That's when I discovered a broken retaining clip, I also replaced the o-rings and clips and now they both turn the same amount from CCW to having the damper flush with the valve..about 3 turns each.
Charlie
Charlie

This thread was discussed between 17/04/2002 and 01/05/2002

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