Topic: 4 Bolt or 2 Bolt Main
in Forum: C3 Engines
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Is there any way to tell if it's a 4 or 2 bolt with the pad numbers. I got these #'s off the block front passanger side, V0515ZAK. Next set below 1AS431943, these #'s match the VIN on the drivers side windshield piller.
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Lifetime MemberHOWELL, NJ - USA
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I think you want the block casting # - usually 7 digits on the rear drivers side of the block - just below the head.
LukesVette 2008-04-05 18:05:39
eg 3970010
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ZAK = L48 engine...not likely to be a 4bolt main...
Problem is, without actually pulling the pan and looking, there's really no way to know. Casting #s are not 100% accurate in telling if it is 4 or 2 bolt mains. Normally, the only engines using 4 bolts were the higher output engines, ie: LT1, L82, ect.
Problem is, without actually pulling the pan and looking, there's really no way to know. Casting #s are not 100% accurate in telling if it is 4 or 2 bolt mains. Normally, the only engines using 4 bolts were the higher output engines, ie: LT1, L82, ect.
Joel Adams
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14010207 is the # that was on the back of the block. From the searches that I've done it could be a 4 or 2 bolt. Like you say no way of knowing unless I pull the pan. That looks like a really fun job. Is the gasket a one piece deal?
Lifetime MemberHOWELL, NJ - USA
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My79 was an L48. When I pulled the pan off the motor, it turned out to be a 4 bolt. All depends in whats on the assembly line when they run short....
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[QUOTE=Metal Man]Is the gasket a one piece deal? [/QUOTE]
Sure it is...one piece on the right side, one piece on the left side, one piece at the front, and one piece at the rear!
Sorry...a little mechanic humor there...
Is it really important enough to pull the pan just to find out?
As I said, an L48 ain't likely to be a 4 bolt, unless someone has built it that way, in which case it wouldn't be the original engine for the car.
The only exception I could see for that would be if the factory ran out of 2 bolt blocks for a period of time, and they just used the 4 bolt blocks..it has happened, but it's just not a likely scenario...
Sure it is...one piece on the right side, one piece on the left side, one piece at the front, and one piece at the rear!
Sorry...a little mechanic humor there...
Is it really important enough to pull the pan just to find out?
As I said, an L48 ain't likely to be a 4 bolt, unless someone has built it that way, in which case it wouldn't be the original engine for the car.
The only exception I could see for that would be if the factory ran out of 2 bolt blocks for a period of time, and they just used the 4 bolt blocks..it has happened, but it's just not a likely scenario...
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Like Joel said... Is there some reason you need to know, or just curious? If you need to know, it is not too hard to drop the pan in the car. Just unbolt the idler arm and pull the tie rod assembly down a bit. The pan is then clear. I know someone who occasionally forgets to drain the oil first, then I have (I mean, he has) a mess to clean up.
The new one piece replacement pan gaskets are nice. Be sure to put a dab of sealer in the corners where the main caps touch the block.
Larry
The new one piece replacement pan gaskets are nice. Be sure to put a dab of sealer in the corners where the main caps touch the block.
Larry
OR....you could rent or borrow a nice bore scope to check it out....now who was the guy here that just got one of those?......hmmmmmmmmm........I think his name started with a J.............
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#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
[QUOTE=MikeMc71] OR....you could rent or borrow a nice bore scope to check it out....now who was the guy here that just got one of those?......hmmmmmmmmm........I think his name started with a J.............[/QUOTE]
Hmmm...now there's another useful idear...
You'd still need to drain the erl tho...
Hmmm...now there's another useful idear...
You'd still need to drain the erl tho...
Joel Adams
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[QUOTE=Metal Man]...V0515ZAK...1AS431943, these #'s match the VIN on the drivers side windshield piller.[/QUOTE]
[/QUOTE]
It's original; it's an L-48; and it's almost certainly a two bolt main.
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