Detroit 6V53 marine motor transmission swap

75GMC

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I bought a 6v53 marine motor to replace in my 1975 GMC cabover.
the problem is the new motor won't fit current 5 speed trany.
bell housing on trany is to large.
what options do I have?
 

TNBrett

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Was the previous motor a 6V53 as well? If so, you would probably be able to swap the flywheel housing from the old motor to the new one. That may be more than you want to bite off though I guess. Did you verify that its the correct rotation? Some marine engines counter rotate.
 

NeverHave-I-Ether

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Was the previous motor a 6V53 as well? If so, you would probably be able to swap the flywheel housing from the old motor to the new one. That may be more than you want to bite off though I guess. Did you verify that its the correct rotation? Some marine engines counter rotate.
For a truck I imagine you need standard rotation? Found a marine Detroit that's rated for 400hp that I want to fit in a truck.

Never-Have-I-Ether
 

snicklas

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For a truck I imagine you need standard rotation? Found a marine Detroit that's rated for 400hp that I want to fit in a truck.

Never-Have-I-Ether

Thing you have to remember about any marine rating on an engine, they will always be higher, because they have an unlimited cooling system. Most pull in "lake water", run it through the engine, and then discharge it (open cooling system). That water only gets heated and then ejected. So the cooling water in is ALWAYS "lake" temperature. There is a thermostat to control temps, just like a closed system, but the water that comes in to replace that thermostat temp (~190, would be my guess) is still "cold", so you can pull more hear out of the engine, so you can make more heat (power).

Some marine systems have a closed system. They have a liquid to liquid heat exchanger. The engine has coolant (anti-freeze) running in the water jacket, and the "lake water" only passes through the heat exchanger and the exhaust manifolds, instead of the entire engine. You can still pull more heat out of the coolant with a liquid to liquid heat exchanger, vs an air to liquid heat exchanger.

My guess is, if you dropped a marine engine in a vehicle with a conventional radiator cooling system, it would constantly overheat.... I've even heard Gale Banks in a couple of his videos say he can make a bunch more power in a marine application because of the amount of cooling he has.....
 

DaveBen

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Y'all know these 'Screamin Gimmys are two stoke engines. They may not be legal to install in many states, like California. I owned a 9V92Ta in the 1980's. Fast truck until 2000, when they were outlawed in Calif. I raced my 10 wheel dump truck against many other trucks and won about half the races. I raced guys in REVERSE. I had a 13 speed tranny with 3 speed reverse.
 

NeverHave-I-Ether

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Thing you have to remember about any marine rating on an engine, they will always be higher, because they have an unlimited cooling system. Most pull in "lake water", run it through the engine, and then discharge it (open cooling system). That water only gets heated and then ejected. So the cooling water in is ALWAYS "lake" temperature. There is a thermostat to control temps, just like a closed system, but the water that comes in to replace that thermostat temp (~190, would be my guess) is still "cold", so you can pull more hear out of the engine, so you can make more heat (power).

Some marine systems have a closed system. They have a liquid to liquid heat exchanger. The engine has coolant (anti-freeze) running in the water jacket, and the "lake water" only passes through the heat exchanger and the exhaust manifolds, instead of the entire engine. You can still pull more heat out of the coolant with a liquid to liquid heat exchanger, vs an air to liquid heat exchanger.

My guess is, if you dropped a marine engine in a vehicle with a conventional radiator cooling system, it would constantly overheat.... I've even heard Gale Banks in a couple of his videos say he can make a bunch more power in a marine application because of the amount of cooling he has.....
That's a very valid point. What would make the 6v53T marine engine different from a 6v53T truck engine? There is about a 100-150hp difference. I wonder how much hotter the marine engine does run if it's the same block and all....

These old Detroit's are hard to find information on. I also found aluminum block turbo 6v53s that are ex-military. I'm looking for a shop that specializes in Detroit's to call but haven't found much in the internet. I know little about marine engines, but do know that they typically run at high rpm constantly. Being a 2 stroke diesel that pretty much runs high rpm on the road anyways, I figured that aspect doesn't matter as much.

Y'all know these 'Screamin Gimmys are two stoke engines. They may not be legal to install in many states, like California. I owned a 9V92Ta in the 1980's. Fast truck until 2000, when they were outlawed in Calif. I raced my 10 wheel dump truck against many other trucks and won about half the races. I raced guys in REVERSE. I had a 13 speed tranny with 3 speed reverse.
Texas:cool:

Didn't know the Detroit was outlawed in California. When I get a truck swapped and have a real smoker, I would like to go for a road trip:shoot:

Never-Have-I-Ether
 

DaveBen

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I should have more clear on that. Two cycle diesels were outlawed. I don't think I saw any other two cycle diesels on the roads...
 

snicklas

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I should have more clear on that. Two cycle diesels were outlawed. I don't think I saw any other two cycle diesels on the roads...

I think that depends on where you are. There are no emissions testing here in Indiana and I’ve not heard of them being outlawed. There are still a bunch of them out there in old busses that are still on the road as private coaches / RV’s. I even know of a business in Nashville, Tennessee that runs old Detroit powered busses for rent as a touring bus in Nashville, kinda a a limo service.

There is even a channel that I watch on YouTube called Bus Grease Monkey, that has a business working on Detroit powered busses…..
 

snicklas

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That's a very valid point. What would make the 6v53T marine engine different from a 6v53T truck engine? There is about a 100-150hp difference. I wonder how much hotter the marine engine does run if it's the same block and all....

I don’t believe they run any hotter… that is not what I was trying to say. I was trying to say they could produce more heat, but still maintain the same operating temperature, since the open cooling system can pull more heat out than a closed, radiator can. I believe they would all have the same thermostat in them… but the cold “lake” water coming in, and then being ejected, and replaced with more cold lake water can remove more heat, than a closed loop that has 190 (that’s just for an example, not sure what temp thermostat a Detroit runs, I believe it is a bit lower than that) degree water can…..
 

TNBrett

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That's a very valid point. What would make the 6v53T marine engine different from a 6v53T truck engine? There is about a 100-150hp difference. I wonder how much hotter the marine engine does run if it's the same block and all....

These old Detroit's are hard to find information on. I also found aluminum block turbo 6v53s that are ex-military. I'm looking for a shop that specializes in Detroit's to call but haven't found much in the internet. I know little about marine engines, but do know that they typically run at high rpm constantly. Being a 2 stroke diesel that pretty much runs high rpm on the road anyways, I figured that aspect doesn't matter as much.


Texas:cool:

Didn't know the Detroit was outlawed in California. When I get a truck swapped and have a real smoker, I would like to go for a road trip:shoot:

Never-Have-I-Ether
The biggest difference in HP ratings is going to be from injectors. The truck 6V53T usually had 5A50 injectors and were usually 225hp. The 400HP marine was probably built with 5N65 or N70 injectors. They would have different specs for injector height as well, which is how timing is set. I had a 6v53T that I sold a while back. I had dreams of putting it in a truck, but it is a very big engine, and very heavy. you would probably be fine with 400hp cooling wise in a light weight (by comparison) truck, as you will seldom be working it hard enough to make 400 hp. They typically cool pretty well. Its also one of the only two strokes rated for 2600 rpm. 2600rpm sounds like 5200rpm that's where the "screamin" moniker comes from. The only two stroke Detroit I have now is a 4-53 in a Stewart and Stevenson generator from the early 60's. I have a video some where of me running that 6v53t on a pallet. If you want I can see if I can dig it up and post it. The military 6V53T aluminum blocks were used in the M113 APC. I had the pleasure of getting to do some work at a BAE Systems facility in Anniston, AL where they were doing refits on those. They had a dyno room where they test ran the engines as well. They were upgraded to electronic controls, and what not, but I believe they were probably making over that 400 hp mark.
 

NeverHave-I-Ether

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The biggest difference in HP ratings is going to be from injectors. The truck 6V53T usually had 5A50 injectors and were usually 225hp. The 400HP marine was probably built with 5N65 or N70 injectors. They would have different specs for injector height as well, which is how timing is set. I had a 6v53T that I sold a while back. I had dreams of putting it in a truck, but it is a very big engine, and very heavy. you would probably be fine with 400hp cooling wise in a light weight (by comparison) truck, as you will seldom be working it hard enough to make 400 hp. They typically cool pretty well. Its also one of the only two strokes rated for 2600 rpm. 2600rpm sounds like 5200rpm that's where the "screamin" moniker comes from. The only two stroke Detroit I have now is a 4-53 in a Stewart and Stevenson generator from the early 60's. I have a video some where of me running that 6v53t on a pallet. If you want I can see if I can dig it up and post it. The military 6V53T aluminum blocks were used in the M113 APC. I had the pleasure of getting to do some work at a BAE Systems facility in Anniston, AL where they were doing refits on those. They had a dyno room where they test ran the engines as well. They were upgraded to electronic controls, and what not, but I believe they were probably making over that 400 hp mark.
That's great to know. I've read similar things. The injectors sure are pricy, I'm seeing about $400 per an injector. I don't know a good source of parts for these engines though. Seems like there's no performance shop that deals with them exclusively. I'm itching for a project. I have access to three different motors in my area. A N/A 6V53, a Aluminum block turbo 6v53 and a marine block 6v53. Now if I understand correctly these are the same engines with only difference in injectors and perhaps a turbo, its possible to push 400hp in the aluminum block as you say? A video would be pretty cool. I really need some solid sources to read. I've just found forum information so far. Any articles would be appreciated.

Yea the engine is pretty darn heavy. The idea would be too beef suspension and try it on the frame. It's been done before on trucks from the 70s. I imagine it would be fine on a 90s frame.

Never-Have-I-Ether
 

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