Drive shaft help! - The Hull Truth

mmaniaci1 · 06-25-2007, 07:06 PM

Hi! I own a 1985 Searay Monaco with a GM small block 228R engine & I-R stern drive. Last weekend we were out and had to get towed in. I pulled the stern drive and found that while the splines on the U-Joint shaft seem to be fine but when I looked into the back of the engine through the bell housing, the splines on the drive shaft end had been sheared off. Does any one know how much this is to repair or how this happens? Thanks! ~Maureen

bigjimmie · 06-25-2007, 07:08 PM

engine coupling
engine out, coupling on, engine back, align, drive back on, more boating

carribbean soul · 06-26-2007, 12:08 AM

http://ishopmarine.com has a very good parts break down I think you are looking for a engine coupling, this would require a engine pull.

mikie · 06-26-2007, 10:36 AM

Was the drive easy to get off? Normally when you lose the splines on the coupling, the motor/outdrive aren't aligned properly. Make sure the splines on the driveshaft are even all the way around and aren't worn on one side. If there is any wear, you may as well change the driveshaft too, not a big job while it's already apart.
If you change the driveshaft, save the old one and use it to align the motor and gimbal bearing after the coupling replacement.

mmaniaci1 · 06-26-2007, 03:58 PM

Thanks for your reply, and good idea on keeping the old driveshaft to use alignment, never thoough of this! Can you tell I've never done this before? I know I should probably take it to a mechanic but I just don'y have that kind of money. Anyway, no, it wasn't easy to get the drive off. Is there any tool you can buy to make sure that every thing alignes? Or is using the old drive shaft to align a pretty sure way? My biggest concern in doing this is making sure everything is aligned perfectly, seeing that this is probably why the splines on the drive shaft were sheared off in the first place. Thanks again!

mikie · 06-26-2007, 09:03 PM

If the unit was hard to get off, it wasn't aligned properly, thus causing your problem in the first place. Use your old drive shaft as an alignment tool, adjusting the motor mounts to gain your alignment. The shaft should slide in completely and bottom out with out having to force it in when you have the motor alignment adjusted correctly.

JUSTINTIME · 06-27-2007, 01:41 AM

u must use the aliment tool unless u want to buy another couple soon and yoke

LouC · 06-27-2007, 09:49 AM

And while you're at it, make sure the engine mounts are not rotted out, which could cause the engine to shift and mis-align the coupler and driveshaft. You can tell by the fiberglass flexing around the mounts because of the weight of the engine, and/or the lag bolts that hold the mount into the stringer stripping and spinning.