Pinion Gear nut...fab a tool??

[deviljohn]

Digging the guts out of a gearcase off a 60deg V6 150, not original, has one piece (modified horribly) drive shaft, non tabbed, 4-5/8" bigger gearcase.

So was able to remove bearing carrier w/ improvised puller and heat, then those cursed snap rings w/ some modified heavy long needlenose pliers, now I scratch my head on the pinion nut and drive shaft removal.

I have loosened the (4) driveshaft bearinghousing plate bolts and have some wriggle room...so how can I get that pinion nut loose??

Thinking of taking a sixpoint socket, cutting down and welding it to a flat bar, thus creating a "pinion nut" removal tool.

Ideas? and after that I assume I can remove the pinion gear, then the propellor shaft assy (after shiftshaft is unscrewed) Thanks in advance

 

[Faztbullet]

Re: Pinion Gear nut...fab a tool??

I use a 7/8 milled down wrench, if you have access to a bandsaw you can cut a 7/8 slot in a piece of 1/4 steel to hold it.

 

[deviljohn]

Re: Pinion Gear nut...fab a tool??

I was able to get it off w/ std open end 7/8 wrench w/ shaft secured in a vise. no real concern regarding drive shaft, as that was the main problem, had been modified by some goombah, only 1/4" of spline remaining so that the shaft would fit......then I used 2x4 wood and hammer to tap the pinion gear loose....18 rollers fell out of the pinion bearing.....

so that was fun, now i got a bunch of labled gearcase parts and more familiar w/ what it takes to get one of those suckers apart....reason for disassy, crack in housing by the V in the shift shaft area, welded once, re-geeked, leaking.....so now the $1000 question is: do I try and have it re-welded, get a new (used) housing & driveshaft and reassemble w/ my parts, or say hell w/ it and find a used gear case that is proper for the engine.....

also, what is that drive shaft made of, SS or some other mixture?? just curious....

 

[Faztbullet]

Re: Pinion Gear nut...fab a tool??

It sounds as someone put a lower unit on engine that had a crossflow(V-6) shaft, the 60 degree shaft is shorter.You likely have the 1 piece drive shaft which will need replaced with a 2 piece style. If it already a 2 piece all you need is correct upper drive shaft. I would replace the unit if mine,as the snap ring housing are getting scarce in my area. Be careful as there are 2 types of housings, snap ring carrier and bolt in carrier. Also you are going to need a driveshaft so if you have 1 piece you will have to convert to 2 piece style. Just look for a 1992 and up and you will have correct style that fits engine. The 1979 -91 will also work but your back to changing driveshaft again. Here are measurements I had post on another site.
1979-91 V4/V6 crossflow and loopers: 21 3/4
1992-up V4/V6 crossflow and loopers: 22 1/8
1991- up 60 degree V6...................: 21 5/16
1985-1994 V8...............................: 21 3/4
All measurements from top of driveshaft to underside of water pump wear plate. All rounded to nearest 1/16. All measurements for 20" shaft models. Add 5 inches for 25" models

 

[deviljohn]

Re: Pinion Gear nut...fab a tool??

Thanks Fazt....good info on the list of shaft lengths. As far as I could I discern, measurement from bottom of midsection to the top of spline in powerhead is 21-7/8" on my 60 deg motor. So I need to seek out a proper lower unit. Option b) is to rebuild in a new used case w/ a one piece shaft that is slightly moded. (I have heard of guys grinding off the chamfer beneath the splines to make them work)

One thing for sure is that I have learned way more about working on one of these engines than I anticipated. Bought a re-built engine from a "back-yard" OMC guy in GA, and it's been nothing but a headache since day one. Failed trim relays, Carb/fuel issues, and now cracked lower unit housing w/ a monkey-rigged driveshaft.......shoulda spent the extra 4k and put a new yammie on the back, but oh well..

 

[Faztbullet]

Re: Pinion Gear nut...fab a tool??

If the driveshaft doesnt fit correctly, you can have not enough splines engaged and damage crank, or to much and preload crank upward damaging internal bearings. Grinding the chamfer will not help as the shaft is a little over 1/2 inch longer than needed and crank spline is not deep enough to accept this extra 1/2 inch. I would suggest putting the 2 piece shaft back in a new or good used case.

 

[5150abf]

Re: Pinion Gear nut...fab a tool??

Poke around on Ebay, you may be abe to find a used lower for what that part cost, Pretty uncommen but I got a lower for my 50 with a prop for less than $150.

You may also be able to find the part you are looking for.