251 marine engine

[citizensoldier]

Well I stumbled accross some chrystler 251 marine flatheads. It appears to be the same block as a civi 251 with some extra goop. Will the crank work in a Canadian 251? I will also have some of the marine stuff for sale on ebay in the coming months. If anyone is rebuilding one for a boat let me know.
gear driven cam,oil cooler, marine intakes, updraft Zeinith carb,prop drive trans,and so on..
The crank look good I just wonder about the crank tail shaft? It looks bigger but still has the gear drive on it..

 

[SasquatchSanta]

It would be interesting to know the power curve on the marine cam. Given that marine applications demand maximum torque, the cam may be just what the doctor ordered.

My guess is that the crank will bolt right up to the standard automotive (perhaps the more appropriate word should be "truckomotive" drive train.

Keep us posted.

 

[citizensoldier]

I never thought of the cam torc curve.. I do know they are re-balanced built for sustained RPM's.. Its a real neat set up.. All gear driven and was mounted in the boat backwards... I sure hope this crank will work and has no cracks. All the bearings are still standard so I dont think it has ever been rebuilt. I also like the gear driven oil cooler. I was trying to figure out if I could mount that on the motor for a M37.. this would reduce engine heat and therfore reduce wear..
Whats the length of the rods on a 265? and a 251? .. I guess it could be either?..or maybe a 237

 

[doghead]

Since you are surrounded by water on 3 sides, why not call a few old marinas in your area. Maybe you can find a boat mechanic with some knowledge of this motor and maybe they can tell you what you need to know(as far as interchangeability). Good luck.

 

[amanco]

One thing to verify, I know that the marine version Chrysler 440 runs backwards compared to the automotive version. You may end up with 4 gears back wards and one forward

 

[citizensoldier]

The crank should turn either way.. The gears driving everything else might be reverse..

 

[citizensoldier]

Re: RE: 251 marine engine

Since you are surrounded by water on 3 sides, why not call a few old marinas in your area. Maybe you can find a boat mechanic with some knowledge of this motor and maybe they can tell you what you need to know(as far as interchangeability). Good luck.

I have and will continue to ask some of the old boat guys. The problem is they used these in Chris Chrafts and that crowd around here tend to be a little ... well... stuck up and of a higher pay grade. They dont like to talk to us redneck OD heads.. But I will keep trying.

 

[doghead]

RE: Re: RE: 251 marine engine

Living as close as I do to the St Lawrence River, I know the type!

 

[amanco]

RE: Re: RE: 251 marine engine

The crank should turn either way.. The gears driving everything else might be reverse..

The crank may in fact run either way, but the cam, no way. I am in no way a marine engine expert, (I just play one on tv) but I do collect antique engines. That engine may run forward I duno? Just saying check and find out!

 

[spicergear]

RE: Re: RE: 251 marine engine

On other marine engines, chevrolet for example, they take out the chain drive for the timing set and replace it with a gear set that allows the crank to turn reverse rotation but still allow all the other jazz (oil pump, distributor, cam and valve train) to run its normal direction. I would guess it would be set up on the same principle or it could pull intake through the exhaust ports-- ??

 

[Superdave]

If my memory serves me correctly the 251 has a 7 7/8" measurement from center to center and the 265 should be a 7 3/4"

Dave

 

[acetomatoco]

I have a nice 12 hour Chrysler 413HD Industrial/Marine motor...with hand operated clutch...for your HD application.

 

[citizensoldier]

Hi guys.. I have ran into a snag and need a little info on 251 crankshafts.
I found a replacement crank for my engine out of a 251 marine engine. The marine engines had all gear driven cam shafts and oil coolers off the end of the crankshaft. Anyway, the front noze shaft on the Marine engine measures 1.530 and the old crank measures 1.560.. Can this be ready sleeved and work with the old bottom timing chain gear? Or was there two different timing gear sizes?
I am thinking they machined it down for the marine application but am not sure if there was different sizes produced.. I know there are two different timing chain/gear sets produced a older and newer version. But, I think that is just more teeth on the gears?
Any help is appriciated..