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2025 C2 of the Year ('64-'66) Finalist - Unmodified
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roller lifter locations?
My motor has been together now for 20 years, Cast iron block, Cast iron heads, full roller bearing cam, high lift roller cam, roller solid lifters, and roller rockers.
I plan on taking the heads off this winter because my #8 slug is almost 8lbs lower then the other 7 and would like to hope its the head gasket ( I ran it hot for about a mile this summer, heater hose poped off the intake) or a valve leak. The motor maybe has 20,000 miles on it.
My question, do I need to mark were evey lifter pair were so I have to put them back in the same spots?
they also don't have to come out to pop the heads. cam out or engine upside down yes... 8 lbs compression is not a huge drop. especially for a couple hundred mile a year car. unless your 1 mile this year was four trips down the drag strip...
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Originally Posted by derekderek
they also don't have to come out to pop the heads. cam out or engine upside down yes... 8 lbs compression is not a huge drop. especially for a couple hundred mile a year car. unless your 1 mile this year was four trips down the drag strip...
I don't drive like I'm going to church all the time, but it has seen 6,000 a few times, but most of the miles are just cruising trips.
I am most worried when I drove it home (about a mile and a half) after the heater hose blew off and emptied the coolant out causing this low cylinder pressure. there is no evidence of any coolant entering the oil. (oil clear and clean, had the intake off just after)
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Originally Posted by gkull
IMO compression testing is....
Do a leak down test to actually see the health of your motor.
20,000 is lots of miles on a high rpm motor
I do not have the tools to do this (yet) I was just thinking it is time to do a little visual inspection (heads off and look at the cylinders and valves)
But thinking of your suggestion, I think I will try the leak down test first, Thanks
You need a good compressor to supply constant 100 psi and the tester which I bought from summit racing.
My motor was reading @ 3% on all cylinders after a couple of race years doing 7500 rpm in every gear that I was using. It doesn't bother me to break stuff!
I screwed up and was looking for the connector that go's on the temp sender. This was back in 71, and on my 67 that I had a SB in. It had about 1,000 miles on it and I went thru the gears. I had a regular altinator (non vette) and the alt cooling fan flexed enough to take the belt off. Gage was inop because I didn't have it hooked to the sender.
Well it suffered compression (evenly) and after about 15,000 miles I pulled it and all the top rings were broken. Head gasket was thin metal and both were in good shape.
Hope you didn't break a ring, and the advice of a leak down test is a good one. If your lucky you only scorched the cylinder walls which has a good chance of seating in the future.
You need a good compressor to supply constant 100 psi and the tester which I bought from summit racing.
My motor was reading @ 3% on all cylinders after a couple of race years doing 7500 rpm in every gear that I was using. It doesn't bother me to break stuff!
If he's down 4% on one cylinder and oil is clean, no smoke out the tail pipes,......I would leave it as is. With 20,000 miles on the clock the rings aren't even seated yet. (Kidding)