Block Compression Test

[Torontocity]

Hi All...When i got the boat they said it have a Cracked Block..GM 140 with alfa1 o/b. Upon close inspection i dont see any cracks...someone said it might just be a blown Cyl.head gasket...there is water in the oil,and when i pulled the plugs ..no.3 plug is some rust. Either way i got a block..but it dont have Head on it but all else..Pistons and so on...Question is how can i test the block to know if the rings and so on is good?...I dont want to go changing if i can getaway with it...any thoughts?

 

[Coors]

Re: Block Compression Test

search 'pressure test block'

 

[Bondo]

Re: Block Compression Test

but it dont have Head on it but all else..Pistons and so on...Question is how can i test the block to know if the rings and so on is good?...

Ayuh,.....

Basically,.... There's 2 ways to do it,.....

1 way is to take it all apart, Clean everything, Mic,+ measure everything, Clean everything,...
And reassembley itwith New Rings,+ Bearings......
Or,......
Throw a Head on it, get it ready to Run,... Do a Compression Test,....
Then find out you should have Rebuilt it before you put it Together......

 

[Don S]

Re: Block Compression Test

On the 3.0L, in order to pressure check the cooling system of the block, just disconnect the hose between the thermostat housing and the exhaust manifold. Plug/cap off the thermostat housing. Then remove the hose between the transom shield and thermostat housing. Then adapt a hose to fit the thermostat housing fitting and a pump to pressureize the system to about 10 to 15 psi.
To test the rings, start with a compression check but the engine really should be run and warmed up after sitting for a while or the test won't mean much. Then move on to a leakdown test if there are problems with the compression test.

I am also assuming you are asking about the original engine, not your new block.
You can't pressure check anything on it with no head.

 

[Silvertip]

Re: Block Compression Test

If you have the head off and see rust in #3 you are wasting your time just reassembling it because even if it does run, it won't for long and you will be doing it all over again. Pull the engine, disassemble it down to the bare block, drop it off at a shop to have it hot tanked and checked for cracks. You move on from there.

 

[whywhyzed]

Re: Block Compression Test

....

 

[Torontocity]

Re: Block Compression Test

Many Thanks All...Before i go further..lemme take the head off the inboat motor, I'll post the results...THX

 

[Torontocity]

Re: Block Compression Test

Update...i pulled the manifold off and big crack about 8 inchs long, Block is shot..im gonner pull head and hope its well..anyone have a step by step guide to reassemble engine with my new used block? i was assured the rings and bearings fairly new. Thanks much guys.

 

[Bondo]

Re: Block Compression Test

anyone have a step by step guide to reassemble engine with my new used block?

Ayuh,...... Here ya go,.. Right here.......

 

[Torontocity]

Re: Block Compression Test

Thanks Mucho! Bond-0 and also all the guys who adviced me..it might be easier to take this to a shop but the trill of trying to do this can't be denied.

 

[whywhyzed]

Re: Block Compression Test

...

 

[Torontocity]

Re: Block Compression Test

Ye maybe Right! I'm gonner scrap it down..send the head and block to the shop and go for new rings and bearings,Problem is i have to buy so much tools just for a one time use...i'll let yu know..THANKS

 

[Coors]

Re: Block Compression Test

I don't think you need tools, you need a new block.