1991 Mainship Open Bridge 35

[amaysing]

Hello all,

I am new to this forum I have a 1991 Mainship Open Bridge 35. It looks like there are quite a few people on here that own Mainships. I was hoping someone could point me in the right direction to get some info on my Mainship as it seem there is very little info on the internet about it.

If anyone one has a location to find the owners manual that would be awesome.

Current issue I am dealing with is I just got Her running after much work to the engines two 454 crusaders and it seem the last owner put huge props on her 21" with 21 degree pitch. I am trying to figure out the gear ratio in the transmission can't seem to find it on the actual transmission where I was hoping to find it. Then next step figure out the correct size props to install.

Thank you for any help you all can provide.

 

[DavidM]

A quick way to tell how your props are working is to run for a minute at wot. The rpms should hit 4,400 for that engine. Any less and you have too much prop, any more and you don't have enough.

There is also a fairly easy way to tell the gear ratio of it isn't visible. Beg, borrow or buy a photo tach. Run the engine at 1,500 to 2,000 rpm in gear while tied solidly to the dock. You can do this one at a time, but be aware of the asymmetrical thrust.

Measure the engine rpms from the flywheel and then without changing the throttle, measure the prop shaft rpms. Divide flywheel rpms by prop shaft rpms to give the ratio.

David

 

[Bacchus]

Robert
Welcome aboard TF.
Yes lots of current / prior MS owners here.
I wouldn't worry much about finding MS manual as my experience has been the real useful info in most of them is rather slim.
My Bacchus website in signature has a useful links area that has a link to some MS manuals. Didnt look to see if yours was there but you can check.
I have not found any prop info in my manual.
Best bet is to start spreadsheets of all equipment & systems aboard and search online for specificieces of equip. You might get lucky and find another member with same / similar boat.
Have you found the Tranny mfg make, model etc?
Might be worth a call / email directly to them.
Photo of ID plate might uncover someone familiar.