Montego 640: How much oil goes in jetpump?

[stylin99]

I rebuilt my jetpump on the '96 Montego 640 last year and had put the recommended amt of gear oil in the pump (6 oz?) I forget how much. anyway, I had read on here somewhere to fill the pump housing all the way to the top, sooooo before heading out this past time, I dropped more oil 75w-90 in the housing. After riding it for awhile we noticed a foamy grey substance coming out of the side of the ski. Uh oh. We got it back to the dock and inside the hull was full of this foamy oil substance apparantly pouring from the top of the jetpump.

I can only assume that this means filling the jetpump to the top is stupid. Anybody know the technical specs on how much oil it gets? Was 75w not the proper oil?

[Bryan Glynn]

OK I'm really confused. Gear oil goes in some pump cones - ont he rear of the pump, to lubricate the bearings...where did you put the oil??

[stylin99]

Hmmm...not good. I had the 75w-90 laying around since last summer and I could have sworn that was used in the jetpump. Maybe I've made a crucial mistake then. I poured the oil in the small hole on top of the jetpump from inside the hull. It's where the black plastic "accordian" thing goes. What oil goes in with the driveshaft?

[Bryan Glynn]

Grease. Marine grease.

[stylin99]

I'll have to re-read the tech book I have on the Tigershark. I don't remember anything about marine grease there. On our polaris, there is a fitting for inserting grease but I don't think that's right for this hole on the Tigershark.

[Bryan Glynn]

You don't necessarily need to fill it - but grease is what goes on the drivehsaft and around the splines - if you do not have a zerk fitting, then no, you don't need to fill it at all beyond using the grease.

[stylin99]

Just read up on it in the tech manual. It's 6 fl. oz of Tigershark Drive Unit oil that belongs in there. So here goes the fun process of draining the pump and cleaning out the bilge. Oh boy.

[Bear]

I had a similar question in the post - "Tiger Shark - '94 - Montego - Drive Unit Lube"

Mine is of an older design (94), but I know where you are. If you want to use the tiger shark "drive unit lube" (per manual spec) there is a dealer (non-artico, ofcourse) that sells that stuff still in Houston (Tomball really, but that's another story).

If you are looking for any lube that works I used some Penzoil Marine Gear Oil (for outboard motors), it is straight 80w.

I not 100% sure, but the reason you need marine class gear oil is because it has anti-foaming agents and is resistant to elements that exist in the marine enviroment that aren't in your run of the mill automobile enviroment. Sounds like you used automobile grade rear diff. oil.

6 fl. oz. is what my maintenace manual calls for too. The housing should be air tight, hence the expansion bladder on top of the housing.

Also it sounds like you might have over filled the drive shaft housing. Your manual should have a pressure test procedure for checking your drive shaft housing. If it doesn't pass the test you have more maintenance then bilge pump cleaning I'm afraid :( . I would suggest fixing it (if it fails the pressure test) instead of ignoring it.

I can post photos if anyone needs clarification on what I'm discussing. I'm a car guy more then 2 stroke marine person, so my terms may be incorrect.

[stylin99]

I think you hit it squarely on the nose. I did overfill and it did have a foamy appearance. It settled down over a few hrs but the extra pressure caused by the oil swelling pushed it out of the connection where the bladder screws in. The gear oil I got from Walmart may not have been marine grade. I've got to check when I get home. THanks for the input. That explains a lot.