Sea Ray engine replacement

boatmanami

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I have a 1987 Sea Ray. It has a 4.3 six cylinder I was quoted $ at a couple boat repair shops in my area. I called Jasper engines and they quoted $3600 for the engine. So I was thinking of just replacing it myself. I have changed many auto engines in the past so i am confident i could do this swap. My question is how hard is it to get the correct engine ordered? Does anyone have any experience with Jasper? Or are there other companies that rebuild marine engines?
Thanks for any advise.
 

alldodge

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Never used Jasper but many have. Should be easy and just make sure your getting a marine rebuild and not a auto/truck motor. So you need to have marine head gasket, brass or stainless core plugs. Cam is same as a truck
 

Scott Danforth

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pull outdrive
pull motor
tear down old stuff off old long block
Install stuff on new long block
install motor
align motor
install drive
go boating

For your 1987 boat, you should have a 4.3 with flat tappet cams and either a 2-barrel or a 4-barrel

you can get a 1996 or newer 4.3 with vortec heads. you will just need the right intake

your 1987 motor should have batwing exhaust manifolds on it. if so, replace them with the new and improved manifolds and elbows

@Lou C did this a while back
 

Lou C

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Yep replacing the old OMC batwings requires an OMC/Volvo exhaust kit, and Volvo 90* aluminum exhaust pipes & hoses.
 

Bondo

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Ayuh,..... Welcome Aboard,..... I believe it's worth the expense to do the '96, 'n up motor up-grade,.....
 

boatmanami

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Never used Jasper but many have. Should be easy and just make sure your getting a marine rebuild and not a auto/truck motor. So you need to have marine head gasket, brass or stainless core plugs. Cam is same as a truck
Thanks after more inspection we think it is just a bad Head gasket. where is the best place to order a head gasket?
 

Scott Danforth

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Thanks after more inspection we think it is just a bad Head gasket. where is the best place to order a head gasket?
Summit Racing, NAPA, anywhere that sells Felpro gaskets
 

Lou C

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Fel Pro sells a kit for the pre-vortec engines that includes the head gaskets, intake gaskets and distributor gasket. For the Vortec I don't think they actually have a kit, but the HGs I believe are the same, the intake gaskets are different.
 

stresspoint

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Sep 19, 2022
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go with genuine or seirrra head , intake and exhaust gaskets , its worth the expense ,the head gaskets have glue , the intake have alloy core , and the exhaust gaskets are one piece and cheap.

use a good quality hi temp Permatex or the like thread sealant on the bolts.
 
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