mattstryfe

A friend and I decided to perform a valve check/adjustment on my vehicle today. Everything was going well until the last cylinder (2).

2 nuts, 1 on the exhaust and 1 on the intake side, seem to be seized up to the bolt that adjusts the rocker height. There is a slight amount of play in the bolt and nut but it doesn't seem to adjust to where it needs to be. It seems impossible to get the lock nut tight while staying within the safe intake/exhaust ranges.

I have no idea what to do here. More importantly, I have no idea why this is happening. We adjusted cyl1's with no problem. 3 and 4 were within range so they were left alone.

Any suggestions?

thanks,
Matt

mattstryfe

So I think I have diagnosed what I did wrong. I am posting it so no one else does it.

When I adjusted Cyl 2 i saved the torquing for later and figured I would torque them all at once. I did this because 1, I couldnt find my 1/2 -> 3/8 reducer for my torque wrench at the time. And 2, I figured I would just do them all at the same time.

In doing this I think I stripped the inside of the lock nut on the screw/bolt that adjusts the rocker height or gap. I did this by not putting the cylinder I was torquing back to TDC.

So now I am left with what I think are 2 worthless rocker assemblies.




Using this image as reference. I think I need the following:

• 2 x - 14620-PCX-010001008ARM ASSY., ROCKER

This should include the lock nut and screw, correct?

However, is these any way i can just get that screw and nut out? There should be if you can purchase them separately, right? If I can just replace the stripped nut and bolt - that would save me about 400 dollars.

Thanks in advance,
Matt

chino101

Did you take the screw and nut out of the afflicted rockers and inspect the threads of the nut, screw, and rocker? If the thread in the rocker are fine, maybe you can remove the screw and nut from another rocker and see if you can fix it. If that then just order a new screw and rocker.

I'm not sure what type of torque wrench you used, but the 1/2" drive torque wrench may have damaged threads. When was the last time it was calibrated? According to the service manual the torque spec on the jam nut is 14ft-lb, does your torque wrench go that low?

mattstryfe

I can't get the screw and nut off because it seems to have stripped in the area the nut is located at on the threads. It just spins in the same place almost like the the threads on the screw are gone (which I am sure they are). So problem one is... ya, getting it off. I am not to keen on dremel-ing and risk getting metal in the case. I will try and put some inverse pressure on the nut while turning it tomorrow and see if i can get them off.

I am sure it occurred when I didn't have the (2)cyl @ TDC when I was torquing the bolts down. The retainer spring was getting compressed. This is why adjusting and torquing at TDC for each cylinder is crucial. Which I now know.

The torque wrench goes from 0-250. The last time I used it was for tightening the stupid damn axle nuts. I haven't had it recalibrated but I did test it on another nut beforehand.

My larger question is this. Do I have to take the entire rocker assembly and/or cams off to replace one of those screws/nuts? When i try and back one of them the entire way out it puts pressure on the retainer and cam lobe. Perhaps a retainer removal tool that compresses the spring will give me enough room to replace the screw?


--Matt

chino101

Maybe someone with more knowledge about the upper end of the engine can answer your question. But for future reference, most torque wrench manufacturers specify specify their torque accuracies at 20%-100% of the full scale working range. So in your case the minimal reliable torque that can be applied with your wrench could have been 50 ft-lbs.

starchland

may as well do the retainers then if you havent. I dont understand how the nut would be stripped though cause you said you already adjusted the clearance and then you just need to torque...which wouldnt have been affected by tdc or not...but yeah you probably over torqued them I like to check clearance, torque, then recheck to make sure the lash didnt change after you torque it. Rotate crank until cams are pointing outwards on any cylinder, do that cylinder

TonysMI4

I have a few extra sets of ( 2 x - 14620-PCX-010001008ARM ASSY., ROCKER )... You will have to take the whole assy off. PM me and we can work out a price.

mattstryfe

I actually just ordered the new retainers. I may as well do this like you said.

To clarify, the reason they were stripped was because I torqued them when that given cylinder was not on TDC. Let that be a lesson to anyone else doing this.

Tony,
I will let you know, thanks. I need to see if I can remove the stripped screw/nut. If I can't I may need to get a couple rocker assemblies.

starchland

It really shouldn't matter assuming the valve adjustment screw isn't moving, whether it's at Tdc or not. Once you dialed in your spec for the valve, that shouldn't be moving when you torque

Billman250

You cannot use a 1/2 drive torque wrench on nuts of these size. Even if the wrench is set to the exact number, you will strip them. Many people do not understand bolt capacities and wrench drives. 1/2" is way over capacitly.

Your TDC positioning has absolutely nothing to do with why you stripped them.

You cannot go back later and torque the nuts after adjusting. 80% of the settings will change.

The cams must be removed to replace the adjuster screws, as they thread out the bottom. But the threads must be intact, or they will destroy the rocker on the way out.