Bad cam lobe would be noisy all the time. Never had a faulty one. The one cam issue I had was a missing key by the end user. He assumed that just lining up the keyways and using loctite would do it.
Fresh Reman Engine Ticking
- Thread starter Hydro-idi
- Start date
icanfixall
Official GMM hand model
bbjordan
Snow Monkey
Hydro-idi
Full Access Member
Well I tried leak down test and all I hear is air coming from the lifter area in engine. Thinking the air is passing rings because they haven't had much time to seat properly. So......the only real way to get down to the bottom of this is to pull the drivers side head and see what the hell is going on in there. Only way to be sure in my books. I will have her off in a couple hours. Hey, it's all part of the fun! 
Hydro-idi
Full Access Member
Verdict is in and it ain't looking good. We got piston to intake valve contact on all cylinders. The front drivers cylinder closest to rad is the worst. You can catch your nail on piston indent but doesn't look very deep. Looks worse than it actually is. They just kissed the Pistons. I will post pics when I get a chance. Looks like other head is coming off. Now what's the next step to resolving this issue?? I am hoping I don't have to take engine apart and shave Pistons. Any other recommendations fellas??
crash-harris
Breaker! Breaker!
Shave the pistons or install thicker gaskets.
Did the engine that the heads came off of have the pistons shaved? Was the current block decked?
Did the engine that the heads came off of have the pistons shaved? Was the current block decked?
Ian, you need to measure the valve to the deck of the head dimension.
report the readings on intake and exhaust valve.
they should be like .050-.065" recessed in the head.
dont recall exact spec, but it may be in my engine rebuild thread.
1 sec
report the readings on intake and exhaust valve.
they should be like .050-.065" recessed in the head.
dont recall exact spec, but it may be in my engine rebuild thread.
1 sec
Lifters pumped up, weak valve springs, oil pressure valve in header stuck.
Hydro-idi
Full Access Member
No the other engine was original. The heads were decked within spec and re-installed on that original engine earlier this year.
The new short block was decked, don't think the new 0.030 over Pistons were shaved. Lesson learned. Check measurements before you assemble.
The new short block was decked, don't think the new 0.030 over Pistons were shaved. Lesson learned. Check measurements before you assemble.
Hydro-idi
Full Access Member
Russ, I had oil pressure gauge attached to engine when she started for the first time. Oil psi was A ok. You are thinking this was caused because of weak valve springs?
icanfixall
Official GMM hand model
Sorry for the bad find but.. At least you did not continue running it till the noise went away. Now every valve will need to be checked for bends as will the pushrods. Easy way to see if a pushrod is bent is to roll them on a mirror. Using a mirror is better than a plate of glass because a mirror MUST be without waves in it or the reflection will be horrible. Best way to check valves is chuck them up in a lathe and see what the runout is.
Head min thickness.....4.795 to 4.805
Valve recession in head seats
Intake........................0.042 to 0.054
exhaust......................0.051 to 0.063
Block deck height from center of crank
11.37 to 11.41
This is a very difficult measurement to take.
Max amount of piston out of the block
0.031
Head min thickness.....4.795 to 4.805
Valve recession in head seats
Intake........................0.042 to 0.054
exhaust......................0.051 to 0.063
Block deck height from center of crank
11.37 to 11.41
This is a very difficult measurement to take.
Max amount of piston out of the block
0.031
Hydro-idi
Full Access Member
Hey, it ain't the end of the world. Just need to work to solve problem is all. Thanks for the helpful information guys. I'm getting real good at tearing this engine down. Piece a cake! I am pretty confident I can get the whole thing back together in a day lol.
I just pulled the passenger side head and they all look good with the exception of one cylinder where the intake valve just wiped the soot off the top of piston. Not thinking this has damaged the Pistons or rods any. Will be taking them into machine shop tomorrow morning with your guys information and see what can be done. Thx for the support to all.
I just pulled the passenger side head and they all look good with the exception of one cylinder where the intake valve just wiped the soot off the top of piston. Not thinking this has damaged the Pistons or rods any. Will be taking them into machine shop tomorrow morning with your guys information and see what can be done. Thx for the support to all.
icanfixall
Official GMM hand model
No chance the rods are damaged. Just think about the rod material compared to the valve body or the pushrods. Those will bend long before a rod. As for real damage to pistons.. I don't think so. At the center of the piston the thickness is around 560 to 580 thousands thick. and thats the smallest demen of the piston thickness. They get substantially thicker near the edges.
You really need to find out the valve recession and the piston protrusion.
You really need to find out the valve recession and the piston protrusion.
