Rear Motor Mount Setup
 

Boat is a 38 Fountain with SSM #4 drives. Bought boat without power. The boat had rear engine plates, as the aluminum L brackets are still there.

My original plan was to use the ears that mount to the tranny, and get thru bolted to the inner transom plate. However, the ears i had wont work. I have located a set, but now thinking about going to the rear plates.

I am guessing the rear plates are pretty much a standard like the front ones? My bellhousings are the dual cooler type. Im guessing i just need to remove them, and have them machined so the plates can sandwich in there?

Just trying to figure the best route to go on this.

bilge

I have a set of v mounts front tube / rear plate call if intrested
but you are on the right path.
Jim
573 346 5250

I got one rear plate from my buddy. Might need one more. Good on the fronts.

I was gonna sell both sets for what i paid 300
let me know I have family in Chicago. might help on shipping.

the rear motor plate mounts between the blobk&THE BELLHOUSING,NO MACHINE WORK NECESSARY.

yes, but the starter mounts to the bellhousing, so if i just bolt the plates on, the starter gear wont engage far enough.

If your starter is a rear mount (bell housing mount), there were two part #'s for the bell housing...with and without engine mount plate. The without bell housing could be milled/modified if necessary. You could also look at where starter gears are wearing to see if the starter can handle a 1/4" less engagement if the rear mount plates are added.
At then end of the day, the Gil type tranny support mount is likely going to be less re-rigging and easier to align the engines. To do this right, it is really a pretty big project. This is likely why the rear mount plate was removed.
When we added the rear plates, we used a short block, alignment tools, new angle mounts and marked all in place. Then made all and drilled to fit.
In many boats, it will be difficult to work with a fully rigged engine...no room.

I went through the exact same issue. Project boat with no motors and #3 drives. There were rear plate mounts so I bought front and rear plates. We assembled and installed the motors with front and rear mounts. Went through 2 sets of starters before we realized the bell housing had to be machined 1/4". Anxious to get on the water we took out the plates and bought the transmission to transom plate mounts. Ran this way for 5 years. This year we pulled motors and went back to rear plates (after machining the bellhousings I already have).

That is why I am selling the transmission mounts you inquired about. :)

You either have to buy "cut" bellhousings or machine what you have. That lesson cost me a few thousand dollars.

As much as I would like to sell my transmission mounts, if you have the rear plates I would machined the bell housings and use the rear mounting plates. In my opinion it ends up with a very solid installation.

Good luck,
Doug

Fixx
 

Joe,no machine required,remove bell housing,remove flywheel,knock out the doll pins,install longer ones reverse prociedure but make sure you loc tight every bolt (Blue)..

i got you covered on the starters too!

ok guys. Bought waterbums ear setup, and dropped a motor in to see how its gonna line up. Everything went perfect, except the motor needs to go back 1/2" for the rear bolts that go thru the ears and inner transom. With the front plate bolted to the L brackets, im 1/2" too far forward...damn

Now do i move the motors back to where they need to be, and re-drill the holes in the stringers, or new holes in the Aluminum angle iron to give me that 1/2"...

best to make new L brakets you dont want more holes in your stringers

Could you just use a 1/2 pc of alum for a shim between the motor plate and the L stringer motor mount? Maybe drill one hole, thru bolt and then mark spacer with a transfer punch. Drill all holes in the spacer slighter larger than the mount bolts for a easy install.

i agree with tnt1,get new l bracket and drill new holes.
.

Mr fixxall;

Can you elaborate on this? We are going throught it currently on a new rig job -- what does installing longer dowell pins do?
What am i missing in your description?
Are there different starters available for this application?


Thanks, Dave

U need to just mill down the bellhousing 1/4 inch and all is good !!!!!!!
the ring gear on the engine is also running on the back side , DONT FORGET THAT !

just mill off whats added on the rear mounting plate ..but if they are already for rear mounts ..watch out !

Not sure what you are rigging, but I have the mounts for the ssm setup that bolt to the transmission, then inner transom plate. I went with rear raceplates, only because that's how mine was rigged. I actually like the ear setup better. If you need the ears, ill give ya a good deal!

Fixx
 

whenever you use a rear stringer mount engine plate your extending the bell housing back .250,your bell housing wont sit rite with the motor plate so you need to knock out the rear engine doll pins and install longer ones so you wont sheer the heads of the bolts off..the pins are designed to keep the engine and bell housing in line and if the bell housing does not sit even with the pins it could throw the crankshaft center line off then you could have other problems like wearing out the mains or the transmission pump..
http://www.jegs.com/i/JEGS-Performan...22006/10002/-1

as for starters their are 2 different lengths to the nose of the starter,depends on how deep the starter ring is..

Not trying to start a fight here but I have never heard of a longer nose for a top mount starter. I have always thought those come in one flavor. And if using one the ring gear is always on the rear of the flywheel. Block mounted starter uses ring gear on the front and does not care about the flywheel housing.

Also, do not forget about the engagement of the transmission to the drive plate. Most of the flat style plates barely grab as it is. The dished plates are better in that regard.

Yes, kudos on the long dowels. They are often overlooked.

Some of the standard flywheel housings don't really have enough meat on them to machine. We have taken meat off both the front and back sides (both starter & trans) to get that 1/4".

The front/rear mounts are a really good idea if the boat is going to be run hard. I personally dont like to see the engine supported by the transmission. Have seen more than a handful of cracked flywheel housings. Also the transom deflects more than you would believe. Put a Go-Pro back there and run out to one of the cribs (you Chicago guys know what those are) one day this fall when the wind is out of the NE and take a look.

Can anybody post any pics on this?

rear plates
 

you guys are a wealth of info !
i'm picking up parts now to upgrade a scarab s type.
i have a chance to pick up front and rear plates
it's a TRS 72c set up, and i'm wondering about losing that 1/4 inch between the trans and coupler,
what else am i missing here

any advice is appreciated

thanks

I measured mine and agonized over what to do about this issue a few months back. I've done some custom stuff where I ended up milling the bellhousing down to make the trans input spline line up perfectly with the flywheel plate splines, but this time I was using Merc bellhousing coolers, and there was just nowhere to go, not enough meat to machine anywhere. I came to the conclusion that the length of the spline insert in the drive plate is shorter than the splines on the transmission pilot shaft, and I'm getting just about 90% engagement. I figured that if Huber says you can put 1450 lb-ft of torque to the tranmission, then it will take my 1000 lb-ft as long as I've got at least 68% engagement.

rear plates
 

good point, thank you

Why not just use the factory trs tailstock mounts?