how to tighten thread on the valve lash adjustment screw

[stroker402]

I haven't seen this question answered yet here.
I went set the lash on my solid cam today and noticed a couple on the adjuster screws are too easy to turn when setting the lash. there is a tiny 1/8" hole on easy rocker hole in the rocker where you can see the threads near the cup of the pushrod. That hole seems to be there for a reason to tighten the threads by maybe going thru the hole with a flat tiny screw driver and just nick the thread so it tightens up the adjuster screw. Anyone ever done this ? Thanks !

 

[younggun2.0]

No! That is most likely an oiling hole. The jam nut is what locks the adjuster

 

[RustyRatRod]

If you are talking about the factory adjustable rockers, they are self locking. Once they get loose, they are worn out.

Take a tap and run it through the adjuster holes to remove any self locking resistance, then get the good Crane adjusters with lock nuts and replace the crappy factory ones. You will have to dress the tops of the adjuster holes on the rockers so the nuts will fit and lock down tight, but it's an easy job.

 

[younggun2.0]

If you are talking about the factory adjustable rockers, they are self locking. Once they get loose, they are worn out.

Take a tap and run it through the adjuster holes to remove any self locking resistance, then get the good Crane adjusters with lock nuts and replace the crappy factory ones. You will have to dress the tops of the adjuster holes on the rockers so the nuts will fit and lock down tight, but it's an easy job.

I didn't even think of the factory rockers.

 

[stroker402]

Yes, these are factory adjustable rockers on 65 commando .
How about the" Blue " locktite ? It doesn't lock tight permantent , you can still move adjuster if used .
We need some old timers to chime in on this one because they would probally recall how they tightened up that adjuster thread . there is a reason for that hole to access that threads .

 

[jimjimjimmy]

Yes, these are factory adjustable rockers on 65 commando .
How about the" Blue " locktite ? It doesn't lock tight permantent , you can still move adjuster if used .
We need some old timers to chime in on this one because they would probally recall how they tightened up that adjuster thread . there is a reason for that hole to access that threads .

your question was answered by an oldtimer in post 3 that's how you fix your problem for ever .

 

[IQ52]

Yep, whatever you do, don't listen to the 'oldtimer' in post #3 who has already given you the correct answer.

 

[toolmanmike]

Pics of the Crane rockers with the locknut.

 

[Jadaharabi]

The hole that you see on the back is the factory hole from drilling the oiling hole to lube the rocker arm. If you are going to run high rpm then you need to plug this hole.

Check out
Reworking the 273 Adjustable Rockers

Reworking the 273 Adjustable Rockers

 

[rustycowll69]

I agree with RustyRatRod, with one exception: years ago, I bought a set of those Crane "computer engineered" adjuster screws that were improperly machined. The threads were cut way too small, you could almost put them in sideways.
To spot-face the surface for the locknut, I threaded a rod in a three jaw lathe chuck. Then you just screw the rocker onto the threaded rod, until it bottoms against the shoulder at the thread bottom. Then you just just cut the top of the rocker flat just big enough to fit the nut and box end wrench.

 

[PocketAces]

I got replacement adjuster screws and lock nuts from Summit Racing for my 65 Dart. But I ran into a problem when I put the stock valve covers on and the adjuster screws hit the baffle inside the valve cover. Thicker valve cover gaskets solved the problem for me, but you could also drill holes in the baffle to make room for the screws.

Curious to hear if something can be done to the threads to make them tight again.

 

[rustycowll69]

well, you could distort the threads, by hitting the threads with a hammer, but that is just a temporary fix, and will eventually ruin the female threads in the rocker arm. I suspect an A&P mechanic did just that on that McDonald Douglas planes Jack-Screw, years ago, when it crashed off the California coast.

 

[j par]

I followed the old timer in post threes advice myself and they are good to go for good now

 

[Jadaharabi]

Curious to hear if something can be done to the threads to make them tight again.[/QUOTE]

You can tape the access hole for a #8 set screw. Adjust the valve then tighten the set screw against the adjuster screw. It would be better to do like Rusty said and run a tap thru and get the lock nut and adjuster set.

 

[nm9stheham]

The hole that you see on the back is the factory hole from drilling the oiling hole to lube the rocker arm. If you are going to run high rpm then you need to plug this hole.

You mean to lube the socket on top of the pushrod...

The hole in question is simply a drilling access hole from the manufacturing process. It gets drilled all of the way into the main rocker shaft bore of the lifter (edit: rocker), then oil comes out from the rocker shaft to the adjuster, and runs down the lower threads of the adjuster to oil to tops of the pushrods. So even if you wanted to put a set screw in there, you could...it would not interfere with anything. But I think it might not take much pressure to bust out the side of the adjuster in that area.

The Crane adjuster with locknut solution is the way to go.

 

[Jadaharabi]

You mean to lube the socket on top of the pushrod...

The hole in question is simply a drilling access hole from the manufacturing process. It gets drilled all of the way into the main rocker shaft bore of the lifter, then oil comes out from the rocker shaft to the adjuster, and runs down the lower threads of the adjuster to oil to tops of the pushrods. So even if you wanted to put a set screw in there, you could...it would not interfere with anything. But I think it might not take much pressure to bust out the side of the adjuster in that area.

The Crane adjuster with locknut solution is the way to go.

My bad yes the hole is to lube the tip of the pushrod and the ball of the adjuster not the rocker arm it self. I don't think a set screw will bust out the side of the rocker. I hope it won't because that is how I plugged mine to stop the oil blowing out the hole,

You used the word lifter but I think you mean rocker.

 

[nm9stheham]

Yeah 'lifter'... you know, that other word for 'rocker' LOL

Well, I doubt that your set screws will bust anything as I suspect you are not really torquing them down hard; they just need to stay in place to do what you want. Keeping the adjuster from moving might require more torque and that was my concern over the setscrew idea.