TR4/4A setting valves on TR3 and TR4

[bluemiata90]

I'm trying to tune my cars and have never set valves on a british car before. Does anyone know of a website or can you explain how to set the valves on a TR3 and TR4 engine. Also, when doing a complete tune-up, should you set the valves before you do anything else. I read somewhere about the rule of nine for setting valves, but I can't seem to find it again. /ubbthreads/images/graemlins/confused.gif

 

[Mickey Richaud]

See here for "Rule of Nine":

https://www.mgcars.org.uk/MG_Elec-Tech/Clikadjust_1.html

And, yes, I do the valves first - once they're set, you're done with them.

Mickey

 

[Geo Hahn]

The 'rule of 9' tells you which valve to adjust when. Think of them as numbered 1 thru 8, front to back. When 1 is fully open then adjust 8... when 2 is open, adjust 7... when 7, do 2... when 8 do 1... etc.

Of course they don't open in that order so do each based on what opens next and keep track so you don't miss any.

If you have a hand crank then it is easy to turn the engine with it... easier still if the plugs are out (good time to inspect & clean or replace them too).

If no hand crank then put it in 4th gear and push forward on the top of the drivers side tire to move the engine. Put in neutral and push the car back if you start to run out of room.

There are fancy gadgets for this job but an ordinary feeler gauge has always worked for me. Since they are adjusted cold it could hardly be easier.

FWIW -- I have been advised by someone with more experience than I that it is best to set the valves to .012 (rather than the spec .010). The thinking is that a bit more clearance won;t matter but bad things will happen if they get to tight. Either way, expect to hear the valves when they are adjusted correctly.

When you are all done go back and feel the amount of rock on each rocker when its valve is fully closed to get an idea of what the right gap feels like. Should all feel the same -- double check if one feels different.

Treat yourself to a new valve cover gasket. Some glue them to the valve cover but I have never had a problem getting it to seal up fine with a little blue Hylomar smeared on it.

A valve cover stud may come out when you take the valve cover off since it has been awhile... use a pair of suitable nuts to remove the top nut and then to reinsert the stud. Note that the coarse threads go into the head.

 

[bluemiata90]

Thanks for the replies, that clears up the confusion. I'll adjust the valves tomorrow and see if it makes any difference.

 

[achtungeveryone]

Geo Hahn: thanks for the great info as I also need to check clearance in my 6. Would there be a "rule of 13" for the 6 cyl. ? Is the 1st cylinder on the waterpump side or the rear main side? Or in other words, is the "front" of the engine toward the front of the car? I know I need to have this figured out before I start!
Thanks, Achtung

 

[JFS]

I've used the following method since finding it in a club (I think it was the VTR) newsletter, which in turn I think got it from a Toyota publication: Turn engine to #1 piston TDC by aligning the timing mark and pointer with the distributor rotor pointing to the #1 plug contact. Set both intake and exhaust for #1, Intake for #2, and exhaust for #3. Turn engine one complete revolution (again aligning timing mark and pointer). Set exhaust for #2, intake for #3, and both intake and exhaust for #4. If you have a cam other than the original stock cam, get the clearances from the cam grinder and set them as best you can within the given tolerances. I have checked this procedure with a couple of sports car mechanics who say it should work. I know of no shortcut for the TR6 -- we use the rule of 13. All engine numbering begins at the front of the engine.

 

[pace]

Mickey, Is the Clickadjust worth the money. It looks like a pretty good tool. It seems I always have trouble holding the screwdriver while tighten the nut and have to redo it.

Mike Pace

 

[Mickey Richaud]

Mike -

I don't have any experience with the Clikadjust. Too old fashioned, I guess. I had stumbled on that website a while back to learn about the rule of nine, and was just passing it on. Anyone else use the Clikadjust?

Mickey

 

[sparkydave]

FYI, I found an MG site with a detailed description of why not to use the Clikadjust (www.mgaguru.com). When I tackled my Midget I went by the rule of 9s and used a screwdriver with the closed end of a combination wrench. True, you might need to do it more than once per valve until you get the clearance right, but it went better than I expected.

-Dave

 

[bluemiata90]

JPS, just used your suggestion for setting the valves and it worked great, the valves sound smooth and the engine seems to have more power. The procedure is very easy and requires very little turning of the engine. Thanks for the great suggestion.
scott