Engine bolt patterns and adapters for chevy marine engines

I've searched already, but can't seem to find what I'm looking for.
The similar question has been asked lots, but I can't find an answer.

If you have a boat with a chevy engine in it, I'm assuming 289, 305, 327, 350, 383 all have the same bolt pattern to bolt on a transmission, right?

If someone wants to put in new non chev engines, what kind of adapter do you need?
I know in the truck work, places like "fordcummins.com" make adapters to bolt a cummins engine to a ford transmission, so what is the equivelant to this situation?

Do marine V drives have an SAE pattern with an adapter to chev? Or are they specifically designed for a chev engine if they come with it?

I'm trying to find the method to attatch a 4 cyl cummins to a V drive that has 327's bolted in.

I read somewhere that GM might have adapters as some cummins engines were used in some larger trucks that had the same bolt pattern as the gas engines ?

 

When doing jobs like this it is normal to be able to fabricate such as engine mounting yourself.

Or move the mount location on the boat by glassing in threaded plate pre made to match the foot of the mounting.

There would be little demand in the boat industry for various adaptors mounts.

 

you can buy an sae to borgwarner adaptor for your cummins, you don't give any info so i guess we are talking about a borgwarner . these are common adaptors, ring a cummins marine dealer or marine transmission supplier, they will know. he is talking about flywheel housings frosty not engine mounts. if i was you parkland i would consider getting a marine mechanic to have a look and tell you what you need. you are asking very basic questions about things you should already know if you are doing this work, no offence intended but you will have a lot of trouble doing this work with such a lack of knowledge.

 

Between engine and gearbox there are usually 2 parts: a bell housing for the engine, that complies with an SAE standard and an adapter plate for the gearbox.

There are also engines where the bell housing is part of the block and surely also gearboxes with an SAE bolt pattern. And there are also engines you cannot mate to any SAE adapter or gearbox without constructing your own adapter, like transverse mounted small passenger car engines.
Most engine builders stick to the SAE standard because it allows them to use different gearboxes without the need for special parts.

 

bellhousings are for cars, boats have flywheel housings or covers. cummins are sae as are borgwarner marine. like i said already cdk, it would be a good idea for parkland to consult a mechanic and put together a correct list of parts for the job.

 

They call them bellhousings or bell housings over here.
http://bpi.ebasicpower.com/c/MER2D/Bell Housing Service Kits for Mercruiser and http://bpi.ebasicpower.com/mm5/apps/master/crusader/index.php?MODEL=5&IMAGE=62
I'd prefer flywheel cover because I already have one bell housing on the sterndrive! Technically I think it's flywheel bell housing but everyone abbreviates.

 

Custom bell housings aren't especially uncommon and most can be modified with an adapter plate or just some fancy welding. This is the least of Parkland's concerns on this project and questionable necessity on a V drive setup.

 

V drives are horibble, not only becaue the engine now sits over the most common cause of a leak and maintenance but becaue of the shaft pushing up the gearbox at a longer turning moment than that of a conventional.

V drives are get out of the crap alternatives for difficult designs or installation -to choose one is madness.


The Yanmar installation book suggests 6 mounts on such an installation.

 

Oh no !!


Madness you say?

What maintenance is required, and how often?
I assumed greasing would be the majority of what those drives need ?

If I'm not even pushing the boat with as much power as it was designed to take, am I not at an advantage maintenance wise?

 

Parkland, you'll need to take Frosty as his name might suggest. V drives can be very reliable though they are commonly used to solve problems, more so then to make things efficient. Admittedly, V drives aren't particularly efficient, but they are simple and easy to maintain.

 

You know what would be a cool idea?

using a 10 hp outboard for docking and stuff,

and then have a big I6 diesel bolted right to the prop shaft, like big ships do.
No clutch, no transmission, just throttle.

 

I'd rather have the reserve power and ease of docking with the main engine. Sometimes it's nice to have the umph there when you want to make a correction without people noticing the whining outboard! It would keep the fuel fresh to use the kicker more. It would be a hassle though and to have to lower it every time.

 

Yes but imagine the effeciency of a direct drive prop !!!

 

I was referring to maintenance of the shaft log where the shaft goes through the boat. You have now parked your engine on top of this. Depending on the size of the engine and how close it is getting to this stuffing box can be a pig of a job. If it was leaking badly it is a notorious weak link in an installation.

Because of the V drive gear set on the back of the gearbox you have extended the turning moment of the thrust into the engine. Ie the gearbox is now being pushed up if this in not controlled the shaft will become out of line.

You will need to have the Gb mounted as well as the engine.

 

"I was referring to maintenance of the shaft log where the shaft goes through the boat."

Shaft packing is no hassle in the 21st century with Duramax , adjust it once and forgetaboutit.

FF