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Topic: think I broke something

in Forum: C3 Engines


think I broke something

Posted: 3/4/08 8:10am Message 11 of 23
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fortlauderdale, FL - USA
Joined: 3/15/2004
Posts: 288
Vette(s): 1978 greenwood custom vette, 468 blower motor side pipes.
Ken,
Did the oil in the cyl test, only came up about 15-20 psi, is that about right to indicate rings? I'll do a leakdown test next week when I get the tool.




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think I broke something

Posted: 3/4/08 11:25am Message 12 of 23
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Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas
Scott, a stuck open or closed valve could give you a lower comp reading, but it wouldn't explain the oil loss out of the breather/grommets. It would also have some sort of a miss to it, or "popping" from the intake or exhaust.
Did you squirt the oil into the cylinder, or just pour it in with a funnel or something? If you just poured some in, it may not have actually sealed the rings well enough to raise the test reading, if it is a ring issue.
This is starting to get weird..


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think I broke something

Posted: 3/4/08 11:54am Message 13 of 23
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fortlauderdale, FL - USA
Joined: 3/15/2004
Posts: 288
Vette(s): 1978 greenwood custom vette, 468 blower motor side pipes.
I have an oil squirt can, gave it three good squirts. Raised the PSI, I just did not know what to expect. If I were to opt to remove the head prior to running the leakdown test would I be able to visually see a valve issue? What effect would a blown head gasket have if it were near the #1. I actually think it is the rings, I am trying to come up with possible miracles. I had oil coming down the back of the engine onto the oil pan and I think it came from the dipstick tube ?? Not positive.  If it turns out to be a ring issue, can I replace the piston without removing the engine?? If not, I will have to bring it to a local shop.



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think I broke something

Posted: 3/4/08 5:46pm Message 14 of 23
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CUYAHOGA FALLS, OH - USA
Joined: 12/2/2003
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Vette(s): 1975 C3 Red, T-Tops, Black Interior. All I need is time and money! Getting there!
15 to 20 psi is a good amount.  You have a problem. 
I would go ahead with the leak down test to narrow it down a bit more.  But I'm betting the head will come off, and the pistion come out.  It may have cracked a piston as well.



think I broke something

Posted: 3/4/08 6:19pm Message 15 of 23
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fortlauderdale, FL - USA
Joined: 3/15/2004
Posts: 288
Vette(s): 1978 greenwood custom vette, 468 blower motor side pipes.
Ken, If I take the head off now and there is a problem not with the rings will it be visible? Meaning can I see a valve that is damaged or a blown head gasket. My concern is to take off the head and see a normal looking piston. Also, if it is the rings that are damaged or piston as well, can I repair this without removing the engine? I think if it is the later  it should just go to a reputable shop. 



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think I broke something

Posted: 3/4/08 7:24pm Message 16 of 23
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BINGHAMTON, NY - USA
Joined: 7/19/2003
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If you take the head off you'll be able to check the valves,and the head gasket,the only way your gonna see the rings is to pop the piston up above the top of the block,in my honest opinion ,I would'nt just replace one piston and one set of rings,unless the engine is brand new and I knew for sure everything was up to specs.In my younger days I did it with old clunkers,just so me and my buddies could get back on the road that weekend and go partyin,but I wouldn't do it now.If it was me ,I would pop the head off and see whats up,if its the piston or the rings,I would pull the motor out and send it to the shop,or at least pop the piston out and see what the cylinder looks like, it could be gouged.thats my story,and I'm stickin to it Shocked


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think I broke something

Posted: 3/4/08 8:07pm Message 17 of 23
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Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas
Scott...Ken actually pulled the crankshaft in his car with the engine in the car...on his back...in the yard!
So, yes, you can do it like that, but it sure is a pita.
I really don't think you're gonna have a valve problem, or even head gasket. I think you'll find a problem with either the piston, or the rings on that piston.

If you do pull the head(s), and there is a burned, or blown out section of the head gasket, it will be fairly easy to see.
A valve problem, unless it is actually stuck open, will be hard to determine without removing the valve from the head.


Joel Adams
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think I broke something

Posted: 3/4/08 8:57pm Message 18 of 23
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fortlauderdale, FL - USA
Joined: 3/15/2004
Posts: 288
Vette(s): 1978 greenwood custom vette, 468 blower motor side pipes.
I will see how far I get tomorrow. Thankfully I work from home alot so at lunch I'll go out to the garage for an hour. I am a little out of touch with what the associated costs are to rebuild an engine. Boil out block, replace all freeze plugs, new bearings ( cam and crank ), new pistons, rings, reassemble, any guess $$. Just had the heads done, new cam, new rocker arms and push rods, new lifters, so naturally it had to be a piston DUH !!



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think I broke something

Posted: 3/7/08 11:11pm Message 19 of 23
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Yelm, WA - USA
Joined: 7/12/2007
Posts: 356
Vette(s): 1979 L82 4 speed Scat 383 crank 190 cc Procomp Aluminum Heads 202 160 stainless valves GM Powder metal rods Speedpro H860CP Hypereutectic pistons 280 cam hydralic HEI Pro comp 1.6 roller rockers Mighty Demon 750 Sanderson CC1AP Hedders.
Dude that sucks, I hope it's not too bad! Your cars picture always motivates me to work on mine.
Aside form piston or ring failure, would not having a crankcase evac or vaccum pump on there with the high compression and blower create/cause problems like this?  



think I broke something

Posted: 3/8/08 7:52am Message 20 of 23
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Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/ Am-Fm/map light National/Regional/Chapter NCRS "Top Flight" #2-1985 Bright Red/Carmine Cp.L-98/auto Member: NCRS, NCRS Texas, Corvette Legends of Texas
Scott has sent me some pics of the engine with the head off. I will post them asap.


Joel Adams
C3VR Lifetime Member #56    

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"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"

in Forum: C3 Engines


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