318/392 Stroker Motors

Trowerpower
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Posts: 153
Joined: Sun Dec 07, 2014 8:50 pm
Location: Northern Kentucky

Re: 318/392 Stroker Motors

Postby Trowerpower » Mon Aug 12, 2019 7:12 pm

Well, i have bad news, the port motor has blown another head gasket between cylinder one and three. This is the third one. She will run up to 4,000rpm and then backs off to 3200rpm. No water in the oil thank you Lord. Will probably pull the motor, check for worpped heads and block and try it one more time. Starboard engine still running like a watch.
Trower Power
1987 32ft Marinette Sedan Flybridge
Blue Sky
twin 392 Chrysler Stroker Motors
Performance Distributors
750 Edlebrocks
fresh water cooled
1.5 to 1 velva-drives
Onan 6.5kw gen set

jralbert
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Re: 318/392 Stroker Motors

Postby jralbert » Mon Aug 12, 2019 10:44 pm

Do you have overheating, freq cause of blown gaskets, going on?
-joel-
former owner 1988 '32 FB Sedan
Chesapeake Bay
twin 318 / 240 hp
Potomac MD

Fastjeff
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Location: Rock Halll, MD
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Re: 318/392 Stroker Motors

Postby Fastjeff » Tue Aug 13, 2019 7:24 am

Groan!

In my case, when Mr. Port blew its head gasket, the block was"'fire slotted" (to quote the machine shop) and needed the block milled to eliminate it.

Hope that's not the case here.

Jeff
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington

Trowerpower
Aluminum Star
Posts: 153
Joined: Sun Dec 07, 2014 8:50 pm
Location: Northern Kentucky

Re: 318/392 Stroker Motors

Postby Trowerpower » Tue Aug 13, 2019 8:02 pm

I do not believe the overheating caused the blown head gasket. I believe its the result of a blown head gasket. It started at 160 then fluctuated between 160 and 200. Yea it went to 220 but only momentarily. It runs/starts well, only under wot does it start stumbling. Only further disassembly will tell the story after Labor Day.. Bummer. I think a head is warped or block deck is the culprit. The stroker kit has nothing to do with it as cylinder pressures are not above 160. No hot spots on the block or exhaust manifolds.
Trower Power
1987 32ft Marinette Sedan Flybridge
Blue Sky
twin 392 Chrysler Stroker Motors
Performance Distributors
750 Edlebrocks
fresh water cooled
1.5 to 1 velva-drives
Onan 6.5kw gen set

Trowerpower
Aluminum Star
Posts: 153
Joined: Sun Dec 07, 2014 8:50 pm
Location: Northern Kentucky

Re: 318/392 Stroker Motors

Postby Trowerpower » Wed Aug 14, 2019 8:25 pm

Engine builder will disassemble, diagnose and repair after boating season is over. Taking the entire motor to him.
Trower Power
1987 32ft Marinette Sedan Flybridge
Blue Sky
twin 392 Chrysler Stroker Motors
Performance Distributors
750 Edlebrocks
fresh water cooled
1.5 to 1 velva-drives
Onan 6.5kw gen set

Fastjeff
Site Admin
Posts: 1155
Joined: Sat Jul 12, 2014 5:06 am
Location: Rock Halll, MD
Contact:

Re: 318/392 Stroker Motors

Postby Fastjeff » Fri Aug 16, 2019 7:10 am

With those ARP bolts, you can safely add another 10 ft-lbs. to the torque requirements. Be sure the threads in the block and nice and clean, and use lots of oil.

Jeff

PS: Good luck on this, my favorite Marinette power source!
"We live at the bottom of an ocean of air, not at the top." General Marvage Slatington