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Tips

TR2/3/3A TR3 Valve Adjustment

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TRclassic3

TRclassic3

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OK, another rookie question...haven't done this before. What are indications that valves may need adjustment. If I don't know when the last time they were checked is it a good idea to check them anyway? I have the Haynes manual to follow, but any other advice or tips? Oh, and I do have a silicone gasket for it.

thanks
 
Aloha Ed,

If you aren't sure, a check is not a bad idea. If the clearance is too large, you will probably hear a lot of valve clatter.

It is easier to turn the engine over with all the spark plug removed. If you have a hand crank turn the engine over to get the valve in the fully closed position and the rocker arm clear of the valve. If you don't have the hand crank, you can either push the car in gear or turn the fan (I find this difficult to do on a TR3) to turn the engine over. There is a rule of nine (9 minus the number of the valve fully open is the valve to check the clearance of), i.e. when valve 1 is fully open, check valve 8 clearance.
(9-1=8). Valve 1 is the one closest to the thermostat housing.

If the specified clearance is .010", I find that three feeler gage checks will give the best result. Most manuals talk about a "snug fit" or similar terminology relying on you making a judgment call. Instead use a .010 feeler to set the clearance, then use a .009 as a check, if it does fit thats good, and a .011 if it doesn't fit you've got it right. This go, no go method should be repeated to recheck after all valves have been set.
 
Hi Ed:
They need to be checked with a feeler guage. If everything is stock use the specs in the book. If not stock then you use the specs that came with the new equipment. You can usually tell when they need to be adjusted because they tend to make a bunch of noise.
Special tool needed when checking them while the engine is running. If its not running use a 1/2" box wrench and a flat bladed screw driver of the proper size.
Stock should be set at 15 thousandths.
Good luck, Tinkermam
 
Thanks Dave and Tinkerman

The suggestions are much appreciated. I know that some of this seems pretty basic, but if you have never done it before it's nice to have the tips...

I've done a lot in the year I've had this car that I've never done before....said somethings I've never said before :m. But, in the end it's all good! /bcforum/images/%%GRAEMLIN_URL%%/driving.gif
 
And defintely use the 'Rule of 9'. you can start anywhere in the rotation, and if you observe carefully, you will only have to rotate the engine twice around. And don't forget to remove the plugs, and turn the engine clockwise as you're looking at it from the front.

BTW, you TR6 guys use the 'rule of 13'. /bcforum/images/%%GRAEMLIN_URL%%/cheers.gif

EDIT: One more thing, once you found the first valve that is down, the next will come up (actually down) at a quarter turn of the crankshaft. So with the TR3 four bladed fan, it will be easy to track.
 
Tinkerman said:
Stock should be set at 15 thousandths.
Click to expand...

I think the manual will say .010" (cold). 15 thou sounds like the points gap.

If there is any question, too loose is better that too tight... in fact some set them to .012 just to be double-darn sure they aren't too tight.

Expect them to make some clatter even when correctly set (mine do)... indeed, if you can't hear them a bit then that may mean they are too tight.

Valve adjustment is one of the most enjoyable tasks on these cars (esp if you have the hand crank).
 
Yep! Your right, .010 cold .013 on the inlet. The correct info should be in your manual. When all else fails read the manual, heh.

Anyhow good luck, Tinkerman
 
I've never removed the plugs and just used the starter solenoid button to rotate (bump) then watch the sequence to get the correct valve. Just takes a few minutes that way on a dead cold (sat overnight) motor. They make noise regardless.
 
Tinkerman said:
Yep! Your right, .010 cold .013 on the inlet.
Click to expand...

Not quite right. Very early engines with cast iron rocker pedestals called for .010" on the intake and .012" on the exhaust (or .013" depending on which reference you read).

But sometime before TR3 production, the factory switched to aluminum alloy pedestals and changed the recommendation to .010" for both intake and exhaust. They also recommended that earlier engines be updated with later pedestals (& reduced clearance).

When "reading the manual", it's always a good idea to be sure you are reading the RIGHT manual !
/bcforum/images/%%GRAEMLIN_URL%%/smile.gif
 
TR3driver said:
But sometime before TR3 production, the factory switched to aluminum alloy pedestals and changed the recommendation to .010" for both intake and exhaust. They also recommended that earlier engines be updated with later pedestals (& reduced clearance).
Click to expand...

OK, so my "right" manual says .010 for intake and .012 for exahust. Guess I'm not understanding the comment about the factory switch to both at .010 and when this is applicable.
 
In the TR3 Supplement to the Standard Motors TR2 manual it states that the change to Aluminum pedestals was at engine TS12564E and that from that point the exhaust clearance should be set the same as the inlet (.010").

.010 cold is also specified in the TR3A owners manual ("Practical Hints...").
 
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