I am waiting to hear back from Turner Engineering and Cradock to see what they say.
Tall Ratbag
Active Member
Do you still have the problem? i.e., have you checked it since cleaning up the rocker pads?
I haven't put the rockers back yet. Perhaps tomorrow. Hoping to hear from Turner or Cradock about push rod length.
steve2286w
Well-Known Member
Are the push rods sitting in the brass sliders properly and not jammed off to the side
The head has been skimmed. Had it ever previously been skimmed?
Have you read http://www.expeditionlandrover.info/landRoverFAQ/FAQ_head.htm
Have you read http://www.expeditionlandrover.info/landRoverFAQ/FAQ_head.htm
The pushrods are sitting right in the pocket the way they should
No I measured it. There is a 7 stamped on the raised pad on the head so it should be a later head.
You're good. When it has jammed the rocker is in the valve max open position. The rocker is not free it is still compressing the valve spring. I don't really know about the pushrod. It seemed okay,but I did not try to rotate it. I just tried to put a 1/2 inch box wrench on the adjuster nut and that amount of movement released whatever was causing the jam and the valve snapped shut. No the head is back on. I took it off in desperation and dismantled each valve. They were all free but I spun them in a hand drill with some 400 wet/dry paper and hand lapped the valves just for good measure but they were fine. Seals good and in place.
Can you replicate this everytime when you turn the engine by hand?
How many valves stick?
If you can then try very carefully to push the rocker, it should move with hardly any pressure.
Need to read back, but I believe you have totally disassembled the rocker shaft. Are the rockers “handed” (inlet, exhaust) have you mixed some?
Just chucking questions I know but maybe someone will have a “light bulb” moment.
J
How many valves stick?
If you can then try very carefully to push the rocker, it should move with hardly any pressure.
Need to read back, but I believe you have totally disassembled the rocker shaft. Are the rockers “handed” (inlet, exhaust) have you mixed some?
Just chucking questions I know but maybe someone will have a “light bulb” moment.
J
no I can't replicate it. only happened a few times when I turn it over by hand. Beyond that it has been the engine running very rough, dying rather than idling, vacuum gauge reading ~5 psi indicating late valve timing or sticking valves. Rockers are handed and on the right and left way.
Ok, let's isolate the problem. Get one to stick. Feel the pushrod for movement before doing anything else. If the valve or rocker are stuck then it follows that the cam has moved on and the pushrod should be in danger of falling sideways out of the tappet.
Okay, that is about where I am. Cradock said "std 7 inch pushrods". Turner said the pushrods they use for engines 7:1 going to 8:1 are #546798 and they work. My pushrods are 546798. So I will put the rocker assembly back on the engine and very slowly turn it over by hand to see if one sticks and go from there.
Soo~ the engine is back together again and running better!! I adjusted the clearance to .012, ran the engine looking and feeling the action of each rocker. The valves seem to be operating smoothly oiling well. I think polishing the rocker pads did it! To help a little I have the lash slightly on the loose side at 12 and it is not noisy. It still doesn't want to idle down it dies. And the vacuum gauge is still reading around 5 psi. I haven't found an intake leak. I am going to move the vacuum pickup to the intake plenum directly below the carb mounting and see what happens. I want to thank all of you for your great help and support!! I hope that I am past the "sticking valve" part of the problem. We'll see. Again, your support really made a big difference. I started the rebuild 2 years ago. it was finished about this time last year. Since then I have been chasing all those other issues that can pop up and slow everything down. I'm feeling better!!!
Tall Ratbag
Active Member
>>I am going to move the vacuum pickup to the intake plenum directly below the carb mounting and see what happens.
Yes, you need to use the large vacuum take off for the brake servo.
If you measure near the throttle valve, you are not measuring the full vacuum, and will get misleading results.
Yes, you need to use the large vacuum take off for the brake servo.
If you measure near the throttle valve, you are not measuring the full vacuum, and will get misleading results.
