changing starter from bottom to top mount w BW
#1
Thread Starter
Registered

Joined: Dec 2003
Posts: 131
Likes: 2
From: Lake St. Louis, MO
I'm putting Gen 5 motors w TRS in the aronow. They didn't have the mid-mount plate bt the engine and tranny so I located 2. Problem is the starters are bottom mounted and the hole in the plate isn't even close. Question is do I cut out enough out of the plates to reuse the bottom mount starter....or buy top mount starters. The bellhousing has the mount built in, looks like a no-brainer but I've been told you have to shave down the flywheel to get in to work?? Does anyone know any truth to this or is it an easy bolt on??
thanks
thanks
#2
Registered

Joined: Oct 2007
Posts: 8,439
Likes: 94
From: yorkville,il
the top mounted starter requires a different flywheel,and if you ad the rear mounting plate,you need to mill .250 off the face of the bellhousing that mates up to the block,also need to put a hole in the plate for starter clearance.i dont think you can use the low mount starter with the top mount bellhousing,no pocket for starter clearence.
#3
Registered
Joined: Mar 2009
Posts: 1,758
Likes: 3
From: OFallon,Mo.
I don't know why the lower starter hole don't line up but if your wanting to use the plates between the engine and bellhousings you need the correct bellhousings to compensate for the thickness of the plates or have your existing bellhousings machined down. Then to go with top mount starters you will need to have the ring gear on the flywheels pressed to the rear. Did this boat have TRS's in it already or is this an all new setup? Most TRS's using the Borg-Warner trannies have the tailstock mount that sits on the transom plate. The rear offshore plates are used with big power running in big water for extra rigidity. Never heard of shaving down the flywheel for any reason. As far as an easy bolt on it would be if you had all the right parts. Can you even get to bottom mount starters in that boat if you had to? See your from St Chuck, I'm just up the street.
#4
Thread Starter
Registered

Joined: Dec 2003
Posts: 131
Likes: 2
From: Lake St. Louis, MO
Ahhhh shaving the bellhousing makes more sense, I understand now. Yes its originally a TRS setup, already has the original mid engine mounts in the boat and yes changing the starters would be a beeeeotch to change out! The existing starters def would not mount to the top, they're completely different. But somebody's changed them bc I got all the records from the scarab the motors came out of and they hadn't been out since being installed in 97, and the starters are brand new (receipt from this July), so somebody's limber enough to get down there and swap them out. I was just worried about butchering this plate to get the bottom mount to fit....but I think that's the route I gotta go. Yeah you are rt up the street, I'm from St. Paul, just moved to main st. STC.
#5
If you do go the top mount route you need to cut (or change) the flywheel. The cut is where the ring gear is pressed on. I'ts not a big deal, just need a lathe big enough to hold the FW. Knock the ring gear off with a brass drift, put the FW in the lathe, get it to run true then cut to match where you took the ring gear off. We made a mandrel to mount off the crank bolt holes, makes it fast.
__________________
Marc
www.mercruiserparts.com
www.go-fast.com
www.bammarine.com
www.cyborgtransmissions.com
It's not alive -www.BoatStuffExpress.com - temporarily retired
Marc
www.mercruiserparts.com
www.go-fast.com
www.bammarine.com
www.cyborgtransmissions.com
It's not alive -www.BoatStuffExpress.com - temporarily retired
#6
Thread Starter
Registered

Joined: Dec 2003
Posts: 131
Likes: 2
From: Lake St. Louis, MO
If you do go the top mount route you need to cut (or change) the flywheel. The cut is where the ring gear is pressed on. I'ts not a big deal, just need a lathe big enough to hold the FW. Knock the ring gear off with a brass drift, put the FW in the lathe, get it to run true then cut to match where you took the ring gear off. We made a mandrel to mount off the crank bolt holes, makes it fast.




