1984 90hp shift shaft replacement

[mannyc]

hi - i have a 90 hp yamaha outboard with a soft shift shaft. id like to replace the shaft as its really thin. how do i get the correct part number for the stainless replacement part?? also, how do i tell what model i have? its on a 17' whaler. the black id decal with the model number on the bracket is not readable. i assume the shift shaft is different depending on the engine length. how do i determine that too? thanks for helping a newbie here.

mannyc

 

[mannyc]

Re: 1984 90hp shift shaft replacement

also - for a pretty good mechanic armed with a manual - how hard is this job???

thanks,

mannyc

 

[Capt Ken]

Re: 1984 90hp shift shaft replacement

Well it depends on how hard the powerhead is going to fight you on removal. Since the shift shaft is rusted, then it has to be a salt water boat. There is two shafts, long and extra long. You probably have the long. Those powerhead bolts aren't going to give up easily.

 

[mannyc]

Re: 1984 90hp shift shaft replacement

ken. thanks for the heads up. i have a manual coming this week, but in prep for doing the work, where are the powerhead bolts located so i can start on the process?

also - how do i get a good part number for the long (not extra long) stainless replacement shaft?? if i order the stock part # do i get stainless or another steel one?

thanks,

mannyc

 

[edgutgesell]

Re: 1984 90hp shift shaft replacement

Hi mannyc,

I believe that the 90 hp engine in 1984 came in a 20" length (90 ETLN U.R. Long) and 25" length (90 ETXN U.R. Ultra long) The L=20", X=25". It appears that after 1984, the 90 HP did not come in a 25" shaft, only a 20". Shaft length is measured approximately from where the mounting bracket seats on the transom to the cavitation plate. Yamaha did not come out with the stainless steel shift shaft until about 1994.

The original regular steel shift shaft for 1984 90 ETLN is P.N. - 6H1-44120-10-00
The stainless steel replacement for 20" 90 HP is I think P.N.- 6H1-44120-12-00

Go to http://boats.net

IMHO boats.net is the best place on the net to get Yamaha parts and to track down correct P.N's..

I have a 1985 150 Yamaha, and the power head bolts are beneath a 2 piece apron that attaches to the lower cowling by 6 bolts. My engine has six long (about 5") 8MM verticle bolts that attaches the power head to the mid section beneath the 2 piece apron. There are also 4 short bolts and 2 nuts. Check your manual for the bolt setup on your 90. If you have a saltwater engine, these long bolts get seized from aluminum oxide corrosion on the shank of the bolt and the intermediate housing. As a result, shearing off bolt heads is very common making removal of the power head very difficult. (do a search on "broken bolts")

I hope this helps!!

Ed G.

 

[mannyc]

Re: 1984 90hp shift shaft replacement

thanks. im waiting on the manual before i proceed. i had good luck removing the rusted studs in the cast iron bracket to replace the steering tie rod bracket. i will try and assess the headbolt situation slowly and with caution. i hope heat and prayer will be my friends on this one!

thanks,

mannyc

 

[edgutgesell]

Re: 1984 90hp shift shaft replacement

Do the search at this website on "broken bolt nightmare"!!!! Absolutely read that thread before attempting the power head removal. Pay very very close attention to what Rodbolt says. Also what Ray N. says. I know from experience!!!!

 

[mannyc]

powerhead removed!!!!!!!!!!!!!!!!!!!

powerhead removed!!!!!!!!!!!!!!!!!!!

thanks to the advice here i was able to remove the head. i took it real slow and used my b tank to heat up some of the bolts. the biggest build up of corrosion was in the holes around the bolts, not in the threads. i have to order about 400 worth of parts now to complete. the stainless shaft, all new bolts and odds and ends and im replacing the cast iron bracket that the engine attaches too. that was pretty thin at the top. i figure change it now and run the new stainless shift shaft through it. ill likely have 600 in it by the time im done. after i removed all of the bolts - one snapped at the head, i used my engine lift to raise the powerhead. the one stuck bolt held the engine and actually lifted the boat off the trailer. a little heat and penetrant freed the bolt and i was able to heat it and remove it from the power head. i have to do a lot of clean up tonight!!!!! now i have a rebuilt lower end - a good powerhead and i wont be worried about being stranded in or out of gear. a lot better than 7-8 for a new motor. ill update as to progress. thanks again!!!

 

[YamahaGenuineParts]

Re: 1984 90hp shift shaft replacement

Hello Manny, bases on the info I have read in this thread

6H1-44120-12-00....Stainless is available $74.00 Canadian dollar .
If you wish to order it please send me an email complete with your address and we will get you a complete price including shipping to your door
email info@yamahagenuineparts.com

 

[edgutgesell]

Re: 1984 90hp shift shaft replacement

http://boats.net (Central Florida Yamaha) for 6H1-44120-12-00 is $43.71