Ls1 to omc line up

[1fastjetboat]

Hope some one can help. I put a ls1 in my boat it had a ford 302. With my line up shaft in it goes in and out easy but front of engine is leaning down. My question is does it matter that engine sits lower in front if my line up shaft seems to be right. If I raise the engine in front line up shaft will bind.

 

[bruceb58]

What model OMC?

 

[1fastjetboat]

Early 90s cobra have to get model number off of it tomorrow

 

[1fastjetboat]

It's not the Volvo penta model

 

[bruceb58]

You have a part number for the bellhousing you attached to the Chevy motor.

Did you replace the rear mounts that attach to the transom plate?

You are using an alignment bar right?

 

[1fastjetboat]

Used bell housing that was attached to ford motor it has dual bolt pattern had to change a couple of holes but converted very easily. Had my friend that owns a machine shop make me a adapter for crank to coupler. This made the coupler move 1.5 inches closer to transom so I made spacers at rear mounts to move them forward 1.5 inches to have coupler sit where it was originally.

 

[1fastjetboat]

Yes I am using a alignment bar. Bar feels perfect I have done probably 10 engine setups with factory engines they all sit straight or maybe a little up in front. This one has me worried because of the leaning down in front.

 

[bruceb58]

You need to use the bell housing for a Chevy. The height is going to be different as you have already found out.

 

[1fastjetboat]

Ok thanks I will try to find one

 

[bruceb58]

The adapters that move the rear motor mount tabs sound worrisome to me as well. Looks for a recipe for worn couplers if you ask me. Might as well make sure it is as stock as possible. The transom plate is the same for Ford or Chevy so that is good.

 

[Howard Sterndrive]

regardless of engine, the centerline of the crank and the front shaft of the sterndrive are making ONE straight line when properly aligned. If the engine is up or down at the front, that's an optical illusion. Sometimes the angle of an intake manifold can make an engine look odd, but the engine is level when the crank centerline is level in my mind.

 

[1fastjetboat]

Do y'all know if the rear of engine is lower than it should be would that make the front of engine sit lower to get the alignment shaft to fit properly?

 

[Idlespeedonly]

Do you have any pictures of this setup?
I would like to see it.

 

[bruceb58]

First thing he needs to do is get the correct bellhousing. Right now he has a total hack job.

 

[1fastjetboat]

Do you have any pictures of this setup?
I would like to see it.

I will try to put some on here tomorrow

 

[1fastjetboat]

First thing he needs to do is get the correct bellhousing. Right now he has a total hack job.

If you know someone who makes a bell housing and a coupler for a ls1 to go to a omc cobra drive please let me know.
The bell housing is not the problem. This is the stock bell housing converted to fit the ls1 it has a hole for the coupler to come thru it. The coupler is in the center of this hole where it was with the 302. The reason I had to make adapters to move engine forward by 1.5 inches is that there is a adapter or in the jet boat world we call it a pto that is 1.5 inches thick in between the flywheel and the coupler so I have to put the coupler position in the stock location the bell housing is just forward a bit.
And as for the hack job. You may be able to buy all the stock parts for your boat(s) . I have the ability to build mine when there is none available. I do want my boat to be reliable and no I do not want to replace couplers every month that is why I seek advice from knowledgeable people but i guess you give insults instead.

 

[bruceb58]

If you know someone who makes a bell housing and a coupler for a ls1 to go to a omc cobra drive please let me know.

I did a search on ebay and found a ton of them. And yes, putting spacers extending the transom plate to the bell housing is a hack. Do the job right and get the correct part or you will be spending your days pulling the engine and replacing couplers.

Are you using a 5.7L? What year is the Cobra?

Out of curiosity, what is this engine out of? Carb'd? Fuel injection?

 

[1fastjetboat]

The lt1 would be a 5.7 this is a ls1/ls7 6.0L out of a 2008 Chevy 2500 pick up. It was fuel injected I run a control box for the coil packs and a carb. You maybe wondering why I'm making things so difficult with using this engine but I have grown quite fond of these engines they produce great power and are very reliable I have built and installed these in a few older jet boats and they outperform the big blocks. I have also built these for drag cars that are pushing over 1000hp with nitrous with very min. Defects. I did not put this engine on a dyno but it should be somewhere around 380 flywheel that's very conservative.

 

[1fastjetboat]

Bruce I'm having a hard time trying to upload pics. I am using a iPad maybe that is the problem!

 

[1fastjetboat]

Omc model# 987346