Yamaha Sterndrive Upper Unit Gears

[castrolina]

Hi there, the upper unit gears on my 1990 Yamaha sterndrive v8 5.0 have been destroyed, I believe due to improper shimming. The part numbers are:
Gear 1 6t5-45881-00-00 798$
Gear 2 6t5- 4588-00-00 864$
My question is are there after market gears that will fit this application that are not as expensive? I took the boat in for shifting issues to a local mechanic and ever since then, the outdrive has never been the same. The shifting issues were still there, eventually I bought the shop manual and figured out the shift fork problem with help from iboats. The bearing housing cover that connects the drive shaft to the upper unit was also cracked and appears it was not installed all the way. If I do decide to get this repaired, can I find or use shimming tools needed at auto parts store or marine dealer? Any help is appreciated, thank you.

 

[Scott Danforth]

your lucky you found any parts at all for the yamaha outdrive. only sold in the us for 3 years, next to no support. you may be cheaper to find a merccruiser outdrive complete with transom plate and swap over to something you can get parts for. a complete SEI drive is about what your gearset costs.

 

[Bondo]

Ayuh,.... Welcome Aboard,.... Any parts at all for those drives are tough to come by,.....

Donno whether the gears can be had, or not,....

Have ya been searchin' for rotten hulls with Yamaha drives,..??
Find one with a V8 motor, 'n use the drive off it,....

 

[castrolina]

Would swapping yamaha out drive with mercruiser be considered a repower? What generation of mercruiser, alpha or bravo? Do you know if it would be a straight bolt on with a transom plate. I know sei doesn't have aftermarket yamaha replacement and I have seen complete out drives on ebay for a couple thousand. Thank you for you responses.

 

[Bondo]

Would swapping yamaha out drive with mercruiser be considered a repower? What generation of mercruiser, alpha or bravo? Do you know if it would be a straight bolt on with a transom plate.

Ayuh,.... It would be a Refit, as yer gonna have to swap Everything from the pulleys to the prop,....

The only thing you can reuse would be the Long Block, of the motor,....

There's nothin' that'll bolt to yer transom assembly/ bellhousin', but another Yamaha,....

As far as what generation of Mercruiser, that depends more on yer budget, than anything,.....

A '91 or newer rotten boat with a Merc 305 or 350 will be an Alpha, Gen.II,..... possibly a Bravo,...

 

[castrolina]

Thanks for the input, I have contacted Capt. Ken, he does have the 5.0 v8 upper. But its a pretty penny. I have to think about whether or not I want to keep this boat. I'm not sure I can take on a refit myself. I will keep the forum updated.

 

[Bondo]

I have to think about whether or not I want to keep this boat. I'm not sure I can take on a refit myself. I will keep the forum updated.

Ayuh,..... Probably the Best way to do it is with a rotten donor boat,....

Find a rotten boat with a rotten transom, stringers, 'n decks, that has the driveline ya want,....
Say a 350 Chevy, Alpha 1, or a Gen.II,.....
'bout '83 to '90 is the Alpha 1, post-'91 is the Alpha, Gen.II,.....
Ya oughta be able to find what yer lookin' for, for well under 5 grand,..... possibly less than 1/2 that,.....

The advantage is, ya get ALL the pieces to make it work,... no missin' tiny pieces, with Big prices to find,....
The draw-back is after ya buy the donor boat,....
Ya gotta decide whether to refit yer present barge, or rehab the donor barge to Better than New condition,.......

 

[Capt Ken]

Yep, again the sterndrive parts are going crazy. Yamaha is pricing each gear at $1000 each in the upper for the V8's.

 

[castrolina]

Hi all, back on the water, sort of. I was able to buy the upper unit from Cpt. Ken, installed it and was able to get on the water and cruise for a couple of hours. I started having shifting issues though. I thought it might be the shift fork, but it was already bored out. After some troubleshooting, I discovered my lower shift cable was bent and binding, activating the shift interruptor every time I went forward. Then I also found out my ex-mechanic jimmy rigged the shft cable. the cable barrel was broken and shimmed in with a screw and the part on the shift plate that holds the cable barrel was broken off. The boat runs now, I used some hose clamps to hold the cable for now. I will have to get another shift plate and the correct lower shift cable. Thanks for the input and sorry for the late response, it took me a couple months to save for the upper, and I have been chasing the shift issue for a few. I read the shift cable is easy, but we will see, thanks everyone.

 

[Bondo]

Hi all, back on the water,

Ayuh,..... Thank you, very much for updatin' this for future readers,.....

'n Good Luck with yer drive,.....