Is a 1968 chrysler marine 440 compatible with 71 monaco??

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I have a 71 monaco with a 383/727. I can get a 68 chrysler marine 440 for a decent price. They rotate opposite direction apparently but was told you just need to replace the cam and distributor to make it normal. Never used one before. Does anyone have any experience or input on using this engine. I will attach photos of block numbers. Thanks

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Why would you want to put a marine engine that has spent most of it's life running wide open and the other 1/2 of it's life sitting and rotting, in a car?

Seriously some marine engines may need the crank replaced, (something about rear seal knurl, and oil drill passages) cams a given, timing chain vs gears, Chrysler distributor is the same I hear, just the drive gear/shaft from cam needs to be changed, bearings on a marine engine are at a increased clearance due to the wide open running and are not suitable for running in a automotive application, what else?

I had a friend that crewed on a boat where the owner had just replaced the three Chrysler Marine 440's with 3 CAT Diesels. With the gas engines he was just about able to get out to the Gulf Stream and sit to fish for tuna. Fuel IIRC was 150 gallons so with gas he had just enough to get out and back to the Gulf Stream out of Hyannis MA. With the Cat's he has some 'room to move around' so to say. One night this friend took me over to the boats owners house as he was also a Mopar car owner and thinking I would buy these engines. Standing around his garage looking at his engineless 340 Dodge Dart GTS hav'in a few beers I ragged him on that he should put one of the 440's in the Dart... oh boy you should of heard all the backtalk I got on how a small block will beat a big block on the strip any day of the week. LMAO.

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2536430 is the same block casting number that was used in passenger cars. As noted, the marine engine will probably have the crank with the truck flange. Check the number of bolts on the flange. The engine in the photo has red gasket maker goop installed on the head gaskets, that is an accident waiting to happen as that material is not suitable for use on heads and will blow out. Check the casting number on the heads as some marine engines had a specialty head for marine use with different water passages similar to the industrial engines.

Dave
 
If you ever go to sell your Monaco, having a marine 440 in it will ruin the value of the vehicle. Is your 383 a 4 bbl engine? If so, you should just keep it as is.

Better yet, folks on this forum primarily favor the 71 Polaras, not the Monacos.

I am one of the very few that prefers the Monaco. Probably best to just sell your Monaco as is to me and find a Polara with an original 440 in it. :poke:
 
As stated above, the knurling on the crank where the rear main seal rides is going to be backwards and will make the seal leak like a sieve if run it in the "normal" direction. It's possible that there is no knurling at all, but you'd have to take it apart to find out. Don't know if you can have the knurling polished off, but that could still increase the chances of a rear seal leak.

If the boat used salt water to cool the engine, it's likely that the cylinder heads are rotting away from the inside and will need to be replaced.

The engine would need to be dirt cheap. and you're basically buying a core block to use for a rebuild.

Also as stated above, the high rpm usage in a boat takes it's toll. A friend had a 1964 speedboat with a 426 wedge that had casual weekend use on it and the motor was wheezed out by the 1990's.

Jeff
 
One thing that comes to mind is where is the boat engine from ? I see that your in Detroit which leads me to believe it's out of a fresh water lake boat. However was it ever in a east or west coast salt water ? If it was ever a salt water cooled engine I would not even think of using it as we all know what salt water does to iron. Just my two cents. :thumbsup:

Paul
 
IIRC the crank is different along with the cam.
Typically twin engined boats the "normal" engine gets cherry picked and the other like the one you are considering people cant give away.
Not worth the expense and trouble to make into a passenger engine.
383's respond well to minor upgrades at a fraction of the cost of machining and balancing a 440 boat anchor.
Just my opinion.
Cheers
 
Is this engine out of a twin engine boat? If it is, do you know which side it came out of? The Port or left side will be standard rotation. The Starboard side MIGHT be reverse rotation if it was a full inboard but a lot of I/O were standard and the prop was reversed in the outdrive.

If it was a single engine boat it is most likely standard rotation.

I don't know where the idea comes from that all marine engines scream all day. WFO in most pleasure craft is usually 4500ish and cruise is about 3200. They are always under load tho so there is always the chance of heat and detonation damage if not properly tuned and maintained.

Without a full disassembly and inspection, it's a good core, assuming it wasn't salt water cooled or has thousands of freshwater hours for corrosion to take its toll. If it had closed cooling, none of that much matters as it's no different than an automotive application.

It won't affect the value of your car any more than any other 440 will.

Kevin
 
I got the engine for pretty cheap. The guy said it was right rotation. Its a fresh water engine. The heads are 906. I'm going to tear it apart for inspection. Maybe just replace the crank bearings and head gaskets. Not sure why they have rtv all around the heads. Apparently one was rebuilt. I might blow some money on a complete rebuild and new crank if necessary. I heard the knurl on the crank could be polished off but not sure if that could be done with emery cloth (sandpaper) or machined off. The 383 in the car is a lower compression cast crank. Originally a 2 bbl. Put a cam and a bunch of other parts and work into it and still kind of a dog. I'm just curious as to exactly the difference is between the right turning engine and the left.
 
I got the engine for pretty cheap. The guy said it was right rotation. Its a fresh water engine. The heads are 906. I'm going to tear it apart for inspection. Maybe just replace the crank bearings and head gaskets. Not sure why they have rtv all around the heads. Apparently one was rebuilt. I might blow some money on a complete rebuild and new crank if necessary. I heard the knurl on the crank could be polished off but not sure if that could be done with emery cloth (sandpaper) or machined off. The 383 in the car is a lower compression cast crank. Originally a 2 bbl. Put a cam and a bunch of other parts and work into it and still kind of a dog. I'm just curious as to exactly the difference is between the right turning engine and the left.

Then you didn't do it right.
First off, it's 4000 pounds, it takes a lot to be quick.

Everyone talks great things of 383s. My first 383 was a pig. A 2 barrel engine that I had rebuilt to specs because of the cars nature. It was still the dog you described.
Then I bought a 383-4 car. Same year same body but the car would scream. I now have experience with both enough to know the 383-2 is not the same as the 383-4.

I'm only defending the 383 . I've seen the error of my ways and understand the passion for the 383-4 .
 
I just did a little checking, and right hand rotation is the same as reverse rotation.

Here's some good news though.

Apparently, nobody makes reverse rotation cams for Mopar big blocks anymore and they are very hard to find. I read that it's easy to get at least $300 for one. Currently there's only one on ebay and the asking price is $650. Be very gentle removing that cam!

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There's also a market for the cranks. Here's one that sold for $550, plus $117 for shipping:

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Jeff
 
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I have this rebuilt 63 413 industrial short block. It's 0.60 over makes it 426? It has 8 bolt crank flange. Not really sure what I can do with or salvage from it. Hate to scrap it! Also I believe they are low compression motors
IMO there is too much different with boat motors to use them for cars.
Build your 383 or another 440
 
I'm changing it to normal rotation. The crank flange is the same as my car engine. I'm going to just change the cam, distributor, timing to chain and oil pump. That should be good unless I have to polish off those oil knurls on the crank. All the other parts on the car should work and I have a holley 650 I can use. Thats the plan anyway. I'm going to tear it apart for inspection.
 
I'm changing it to normal rotation. The crank flange is the same as my car engine. I'm going to just change the cam, distributor, timing to chain and oil pump. That should be good unless I have to polish off those oil knurls on the crank. All the other parts on the car should work and I have a holley 650 I can use. Thats the plan anyway. I'm going to tear it apart for inspection.
I think the oil knurls go the opposite direction and may cause some leakage past the rear seal. The rest is fine.

I'll tell you what I'd do with it... It would be a stroker motor, especially if that crank is worth some $$ on eBay. Don't mix the lifters up and the cam might be worth something too.

But that's me...
 
Yea stroker is a good idea. I think I'll do that if that crank isn't something I want to use. Especially if I have it rebuilt. I'd sell the 383 and other parts to pay for some of it
 
Stroker for sure, it eliminates all the issues.
However in my stupid/lucky, I would try converting it to standard rotation. I'm the guy who sanded down a .030 piston to make it fit in a standard bore engine, 7k miles later still kicking.
The distributor is the same, I believe the distributor drive cam gear is the same also and spins direction, has to to make oil pump go in it's proper direction, the teeth on the cam are different to make it spin the same direction.
Good luck I think it will be fine, the knurls are there to lube the seal, if it leaks it is another problem just don't line up all the end sealing surfaces.
 
OK this is the same as I run in my dart. If it is reverse rotation you have to change the camshaft, and distributor and oi pump drive gear. Also you HAVE to get the rear main seal area polished to not have a massive oil leak. The heads and the block are identical just need a the sheet metal for a car. Hope it helps.
 
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