Senior Member
I finally got back to work on my baby over the weekend. I aligned the motor to the prop shaft within about .002" but the motor is now "angled" toward the port side. The front starboard trunion is over-extended by about 1/2".
When I did the alignment I inserted a rubber bushing in the shaft log to keep the shaft centered at the "top" of the log, but I wonder if the shaft is not centered at the "bottom" of the log under the boat, suggesting a bent strut.
Hmm . . . or am I over-analyzing things?
Senior Member
I'm facing similar issues. I centered the straightened shaft in the top end of the shaft log as reference when installing my straightened strut. All seemed fine, but dummy me didn't check the shaft clearance at the bottom of the log until after all the 5200 had set up. I still have a very slight shaft contact with the gelcoat below the bottom of the shaft log. It was much worse before with visible wear on the hull and shaft which prompted me to have the shaft and strut straighted in the first place.
I've since gone back with straight edges, dowels, laser levels, etc. & convinced myself that no reasonable amount of shimming at the original factory strut location would allow the log and strut bores to be concentric. So once again, I don't think Supra used exacting tolerances on these things back in the day. I'm just going to sand the gelcoat for clearance and keep my fingers crossed when I install and align the engine in the next few weeks.
Good luck & keep us posted on your fix...
_______________89 Saltare Resto Project___________
_________Then________________________Now_____
Senior Member
The prop shaft is coming through the center of the shaft log left-to-right, however it is very close to the bottom of the shaft log under the boat. Evidently the strut and shaft log are not precisely the same angle. This is consistent with the problem I had last year when my prop shaft rubbed the bottom of the shaft log.
First pic shows the wear spot on the shaft log and the second shows the rub mark on the shaft. Third pic shows the shaft location as installed now.
THIS IS A PIC LOOKING FROM THE INSIDE OF THE BOAT THROUGH THE SHAFT LOG. NOTICE THE WEAR SPOT.
***NOTICE HOW CLOSE THE SHAFT IS TO THE BOTTOM OF THE SHAFT LOG OPENING. IT IS ACTUALLY SLIGHTLY HIGHER THAN CENTER AT THE OTHER (INTERIOR) END OF THE LOG. ALSO - DOES ANYONE KNOW WHAT TO DO ABOUT THE CHIPPED GEL-COAT AROUND THE SHAFT LOG OPENING??***
Last edited by csuggs; 04-19-2011 at 10:01 AM.
Senior Member
I think I've got the alignment to within .002", but my motor is not lined-up with the stringers, shown by the amount of offset on the front motor-mount trunions. Somewhere I read that there should be no more than 3/4" of the trunion showing on either side, but I've got 1-1/8" showing on the starboard side. Could it be that the stringers are not lined-up properly either from the factory or from replacement? I guess I'll never know.
What might be the danger of running the boat with the motor mounts offset? I'm pretty sure it's the rear mounts that take most of the load for propelling the boat so the front mounts just carry the load of the motor?
First two pics are of the starboard front mount, third is of the port front mount.
Senior Member
Finally, after doing the alignment I installed my new prop. Acme 543 which is a 13 x 11.5 LH 3-blade to replace the OEM 13x13.
Senior Member
Yeah - I too am convinced that Supra did not use very close tolerances in the 80's. I'm pretty certain that no two boats are the same from that era. . .Originally Posted by sybrmike
Senior Member
I wish I had better information for you about that shaft log. What a pickle! Mine lined up perfectly with everything in the factory positions once I had the strut straightened, new bearings installed and a new prop shaft and coupler. I've since had my engine out a couple of times and it drops right back into the same spot without need for any adjustment. Good luck and let us know what you figure out. Have you talked to Jason @ Viper about it, yet?
Former owner of a 1987 Supra Saltare. Current owner of a Malibu 23LSV.
Senior Member
Beutiful!!!
Senior Member
I can't say anything of meaning about the alignment as I haven't got into that area of my boat yet, but I will say that "wow, you are using every inch of space in your garage!" In the prop picture you can see the back of the garage wall.
Senior Member
Rework is NOT cool.
I apologize that this is so long and wordy but I'll try to explain my dismay as briefly as possible. . .
When I re-installed the motor in February I found that the starboard front motor mount did not line-up with the holes drilled in the stringer and if I tried to force a fit it put things in a real bind. So I left that mount unbolted and just barely snugged the other mounts in with the thought that I would do a "pre-alignment" to be sure things would line-up before drilling more holes in my new stringers. So I did the alignment a week ago and then last night I decided to tighten down the motor and re-check the alignment after a final tightening . . .
You can imagine how disappointed I was when I was unable to tighten 6 of the 8 lag screws holding the rear motor mounts! The front mounts tightened fine (of course the starboard one I had just re-drilled and filled the mis-aligned holes with 4200). I think what happened is that Jim's mis-informed (or maybe just lazy) boys did not pre-drill the holes in the stringer at the rear mounts and instead just ran the lags in with a drill motor (I saw them doing this on other projects while I was at Viper last May). I'm guessing maybe the front mounts were predrilled because it would be more difficult to get a drill motor in that area with the motor in place; and if the front were pre-drilled with the motor out of the way that would explain the mis-alignment of the starboard front mount. Anyways, now I plan to replace the 3/8" lags on the rear mounts with 1/2" lags, which also means opening up the holes in the mount itself. I purchased new stainless lags and washers this morning at a cost of $47
Someone putting a boat together should be made aware that you must pre-drill for lag screws - they don't work like drywall or deck screws. If you do not pre-drill them, the lag acts like a drill by removing wood (too much wood) unlike drywall screws.
Two demerits for Viper Customs . . .
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