Cylinder #2 no compression

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azdave
Corvair of the Year
Corvair of the Year
Posts: 1929
Joined: Fri Dec 11, 2009 1:27 pm
Location: Phoenix, AZ

Re: Cylinder #2 no compression

Post by azdave »

I'll be curious to learn how #2 can have an acceptable 15% leak-down test and yet a zero PSI compression test. Doesn't seem possible but maybe the lifters are pumping up (causing a valve to remain open) when turning the engine over fast with the starter but the lifters stay leaked down when slowly rotated by hand?
Dave W. from Gilbert, AZ
65 Corsa 140/4
66 Corsa 140/4
66 Corsa 140/4 w/factory A/C
66 Corsa 455 Toro V8
65 Monza Convertible 110/4
66 Monza Convertible 140/4
65 Monza 4DR 140/PG w/factory A/C
65 Monza 4DR EJ20T/5

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LBC TITAN
Posts: 128
Joined: Fri May 08, 2015 3:39 pm

Re: Cylinder #2 no compression

Post by LBC TITAN »

I took the rockers off and checked for cracks, no cracks. I checked the pushrods by rolling them on a piece of glass, non of then were warped.

I'm gonna try a hot valve adjustment and see if that works. I should notice some sort of change. If not then I'll just be driving it on 5 cylinders for now.

azdave wrote:
Wed Jul 22, 2020 8:44 am
Could be a sticky or seized valve stem not allowing the valve to fully close. As I mentioned above, pulling the valve cover is a pretty easy way to check for cracked rockers, dislocated rockers, rocker nuts that have backed out, pushrods bent or popped out of position and also check for valve stem motion.
Charles
Long Beach, CA
1966 Monza
Turbo 180
Hurst 4spd

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LBC TITAN
Posts: 128
Joined: Fri May 08, 2015 3:39 pm

Re: Cylinder #2 no compression

Post by LBC TITAN »

Well after adjusting the valves it seem to perk up, but it's still running flat a little.

While adjusting the valvesi put an oil pan down to catch the oil. As I as pouring the spent oil I noticed the dreaded shimmers of metal.

I guess the only other thing left to do is to prepare the engine on the stand for first start up.

I'll never forget for 3 months in 2020 I really experienced the sportiness of a Corvair 140 motor. This engine sounded good and ran good.
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Charles
Long Beach, CA
1966 Monza
Turbo 180
Hurst 4spd

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azdave
Corvair of the Year
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Posts: 1929
Joined: Fri Dec 11, 2009 1:27 pm
Location: Phoenix, AZ

Re: Cylinder #2 no compression

Post by azdave »

LBC TITAN wrote:
Fri Jul 31, 2020 8:47 pm
As I as pouring the spent oil I noticed the dreaded shimmers of metal.
Maybe they don't show in the photo but that looks like big chunks of assorted dirt in the photo, not shimmering bearing material floating suspend in the oil. When you look at the oil does it look like really fine metallic paint?
Dave W. from Gilbert, AZ
65 Corsa 140/4
66 Corsa 140/4
66 Corsa 140/4 w/factory A/C
66 Corsa 455 Toro V8
65 Monza Convertible 110/4
66 Monza Convertible 140/4
65 Monza 4DR 140/PG w/factory A/C
65 Monza 4DR EJ20T/5

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