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TR2/3/3A Valve rocker shaft questions.....

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K

karls59tr

Obi Wan
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Thinking about replacing the worn rocker shaft. Looks like a very small pin holds the end collar on. How difficult is it to drift out that pin seeing as how the collars are N/A I don't want to bugger them up?
IMG_20240624_082609.jpg
Also I noticed that the lock nuts on top of the pedestals look like they are gouging into the pedestal tops? Is this why they went to flat washers for the TR4 heads? Would it do any harm to use flat washers below the lock nuts or does that throw out the spec somehow?
 
At this point all should be replaced.Suggest 1.55/rockers as an upgrade.Rollers are best
but wont fit under the stock valve cover so then you get an alloy one.
Mad dog
 
Take a look at the shaft itself by sliding the rockers around. If the shaft is cut up, then get a new one. Last time I replaced the shaft, I sent the whole works to a shop in CA that rebuilds them for I think 225.00; it came back perfect with new bushing and shaft and i like the little nuts.

Steve
 
The caps have a taper pin, so just be sure to tap in the right direction and they will drive right out. Always use washers over aluminum parts.

Strangely, the steel rocker shaft wears much faster than the bronze bushings in the rockers?!?
 
CJD said:
The caps have a taper pin, so just be sure to tap in the right direction and they will drive right out. Always use washers over aluminum parts.

Strangely, the steel rocker shaft wears much faster than the bronze bushings in the rockers?!?
Click to expand...
Do you think the deep wear on the top of the pedestals from the iron lock washers was the reason Triumph put flat washers there for the TR4 cylinder heads? Yes, I bet a new rocker shaft remedies the sticking rockers without even replacing the rocker bushes.
 
There was often an oiling issue in the rockers. Fed from one end only, tends to starve the
distal ones. Also look over the contact point where it strikes the valve. Again, go with fresh ones.
When you take it apart, take some good pictures so the re-assembly is a snap.
Mad dog
 
There are aluminum pedestals and cast iron. I would recommend lock washers with the cast iron pedestals, and flat washers with the aluminum. In general, if you are going to use lock washers with aluminum parts, then use BOTH a flat washer against the aluminum, and then the lock-washer on top of the flat washer. Do not use a lock washer against an aluminum part. Triumph very well may have violated this rule during production!?!
 
Yes it makes sense to have a flat washer underneath the lock washer.The pedestals here are "aluminum". Maybe the PO installed them without the flat washers? Looking at the Moss catalogue the TR4 heads only had a flat washer there. Maybe that's when the pedestals switched from cast iron to aluminum? Maybe I dont need lock washers there at all?:unsure:
 
Ditto on Rocker Arms unlimited, I was impressed by quality and price, something we usually don’t get to use together in the same sentence
 
Karl, I think Triumph did use lock washers on aluminum pedestals, as most of the ones I have seen are gouged badly. I am just saying that I would recommend using flat washers. The lock washer is optional, as, if you think about it, for a split lock washer to work, the nut must come loose first! When the nut is tight, it cinches the split closed, so there is no locking force...until you go to loosen it. If you torque the nut properly, the lock washer is redundant. A properly torqued nut/bolt that is not overloaded will not loosen on its own.
 
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