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TR2/3/3A Using a dial gauge to adjust valves when rocker arm surfaces are worn?

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K

karls59tr

Obi Wan
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It's my understanding that once the rocker arm surfaces are worn you can not get an accurate reading with a feeler gauge. Where is the dial gauge mounted and what is the procedure for the adjustment?
 
One trick that I happened to read recently was to just use a very narrow feeler gauge blade for worn rocker arms. The gauge would need to be narrow-enough to fit within the worn area of the rocker arm surface, but if so, it would give you a true reading of the actual clearance. Haven't tried this technique yet myself, but it seems like it would work well.
 
groupdeville said:
One trick that I happened to read recently was to just use a very narrow feeler gauge blade for worn rocker arms. The gauge would need to be narrow-enough to fit within the worn area of the rocker arm surface, but if so, it would give you a true reading of the actual clearance. Haven't tried this technique yet myself, but it seems like it would work well.
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I don't mind modifying a feeler gauge for that purpose. Do you think 1/4" wide would do the trick?
 
When getting that much wear you could be not getting much oil to the head. I added an extra oil line to head there are kits for most of our cars 4 and 6 Cyl but rockers are not sleeved just steel to steel so wear to shaft and rockers will give you a bit less oil pressure also so less oil to all rockers. I was going to install bronze oil light bushings but rockers $11.00 each and machine shop would have been most of $20.00 each. A plus for extra oil to head is also cooling. Not mush reason to regrind rockers if rockers and shaft are worn that much.
This makes me want to check mine before driving season I guess and a tune-up may be called for. Madflyer
 
Hi karl, Procedure I use is this, as you may know, you have to adjust tappets when cams are positioned on their lowest point or base. Given that #1 and #4 are companion cylinders, so are #2 and #3. Meaning they are in time with each other but doing opposites and so are the valves. #1 exhaust valve and #4 ex valve, #1 inlet and #4 inlet and so on, all doing opposites.
I start with #1 exhaust valve, it will be fully closed and can be adjusted when #4 ex valve is fully open, in down position. Then do the next, turn engine over till #4 inlet is open and adjust #1 inlet. You can save a bit of effort by doing more than one at a time when you see other valves that are open to adjust their companion valves. Mark off the ones you do with dab of grease. I normally remove plugs and select 4th gear and pull car along to turn engine over.
Hope this helps! Rob.
 
Any engine , 4 cyl, has the same firing order: 1,3,4,2. My Toyota Corona repair manual of 1972 is what I have since used: Set the timing mark at TDC and check for closed valves It comes in one of 2 sets: #1235 and #4678. Now adjust the closed valve set, Rotate the crank 360 degrees and adjust the NOW closed valve set. You can adjust 4 valves at a time & with one rotation of the crankshaft. It is all 0.010" making it easy.

LeT
 
Other wear points need consideration as well as rocker-to-valvestem. The rocker bushings and shaft can also become a bit ovaled. Removing the shaft assembly and doing a comprehensive inspection is not a bad idea if wear at the rocker contact faces is evident.
 
Karl,
I'm not sure about thin feelers or dial indicators, I installed new Valves and push rods, polished my rockers as flat as I could and set the valves with a normal feeler gauge....
I Found this method somewhere on the net last year. It is simple and probably just 'in other words'. I'm not sure who posted it.

<Re: setting valves on TR3 and TR4

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.>

Jim
 
Might be time to replace or have them resurfaced if you can't set the lash with a feeler gauge.
 
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