I need specs for 91 VP 570

After about a year of knowing that my boat didn't run to it's potential, and doing rule outs myself. I finally took it to a marine mechanic and did a leak down. Apparently the PO rebuilt with a short block and didn't do something right. I had 95% loss in #7 and 80% in the next one back. I am hunting a long block and S&S in Spokane is recommended by the mechanic. The motor was originally a VP 570 and I assume with the same 280 drive that is now on it and in good shape. Can someone email the detailed specs so that I can forward them to suppliers for quotes? The boat is 22' hard top fiberglass, in good shape. Someone mentioned a cam card for rise and fall specs????

Re: I need specs for 91 VP 570

Whidbey said:

After about a year of knowing that my boat didn't run to it's potential, and doing rule outs myself. I finally took it to a marine mechanic and did a leak down. Apparently the PO rebuilt with a short block and didn't do something right. I had 95% loss in #7 and 80% in the next one back. I am hunting a long block and S&S in Spokane is recommended by the mechanic. The motor was originally a VP 570 and I assume with the same 280 drive that is now on it and in good shape. Can someone email the detailed specs so that I can forward them to suppliers for quotes? The boat is 22' hard top fiberglass, in good shape. Someone mentioned a cam card for rise and fall specs????

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Ayuh,.... Where was the loss goin',..??

A simple Head Rebuild could be All ya need...

Re: I need specs for 91 VP 570

On #7 we could feel it through the exhaust. We stopped after the next one back. On the other-side of the block, one of the middle exhaust outlets had oil. So, I'm not sure where I would take it for a rebuild and with the core I could get a long 4bolt main from S&S for 1235.-- w/ a warranty.

Re: I need specs for 91 VP 570

Since the PO rebuilt it, maybe the valves are adjusted too tight on some of the valves.

PS: Marine engines don't need 4 bolt mains, none of the manufacturers use them, they are normal 2 bolt mains.

Re: I need specs for 91 VP 570

Whidbey said:

On #7 we could feel it through the exhaust. We stopped after the next one back. On the other-side of the block, one of the middle exhaust outlets had oil. So, I'm not sure where I would take it for a rebuild and with the core I could get a long 4bolt main from S&S for 1235.-- w/ a warranty.

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It sounds like yer replacin' the Whole Motor, when it's Just a Head/ Valves issue...

Re: I need specs for 91 VP 570

Don S said:

PS: Marine engines don't need 4 bolt mains, none of the manufacturers use them, they are normal 2 bolt mains.

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FWIW - My 1991 Mercruiser 7.4L had 4 bolt mains . . . I believe. (see below)



When I was looking for a 'replacement' engine, it seemed that most were 2-bolt mains that were available.

Re: I need specs for 91 VP 570

tpenfield said:

FWIW - My 1991 Mercruiser 7.4L had 4 bolt mains . . . I believe. (see below)



When I was looking for a 'replacement' engine, it seemed that most were 2-bolt mains that were available.

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I'm talking about the 5.7's like the OP has.

Re: I need specs for 91 VP 570

The mechanic is a family friend and worked at master marine in mt vernon for 14+ yrs. We pulled the valve covers after we pulled the motor (easier to work on and since he has a vacant hole in the shop w/ hoist and stand) hoping they were to tight. He adjusted the questionable ones (while having me manually turn the crank) w/o results. After we pulled the motor and after I pulled everything off (he's letting me do all the wrenching w/ the use of his tools to save money) he realized we had a 99 5.7 marine. On top of possible valve problems, we found a hairline crack below the port side exhaust that had been doctored. It's carbed w/ the stock holley. Any way I did find specs to compare, but seem to be irrelevant...thanks for your suggestions. At this point, I think I'm looking at a long block....have ya'll had problems with that year being carbed. I still have the choice between 2 or 4bolt main for a difference of about 100 bucks. If I went to sell, wouldn't a 4bolt "sound" more appealing. Anything else to look out for? Thanks!