Couple Jet Questions

[Newriver]

How many washers are normally on a U-4 L? Its on a 1990 Suzuki 40 PU Tiller. Picked one up the other day and I seem to have 11 washers all on the bottom of the impeller and the liner is grooved all to heck.

 

[Darkside]

The book diagram states 8 Shim Washers (Part #21), a Torsional damper (which I never use) and of course the 'Nut Keeper Washer'.

It is possible that older book parts lists/diagrams might show 9 since the torsional damper is something they started using within the last 10 years and the engine is 20+ years old. I gave away all my older books, otherwise I would check for you.

Just as a note- A new kit for your engine would only come with 8 SS Shim Washers (I believe 5/8 size). I checked every parts lists for the nearly 20 engine modles Outboard Jets offer pump kits for and none of them call for more than 8 shim washers.

Hope that helps. -Chris

PS: Is there any wobble in your shaft? What does the plastic shaft sleave look like? If you are grooving your liner and do not have a single washer above the impeller, something is odd. That is unless you are running in a mess of shallow gravel shoals. That can scratch the liner pretty good.

 

[Newriver]

Plastic sleeve was missing when I took it apart. Not sure how to tell if there is too much play in the shaft. It seems to be very little to this newbe. I plan on replacing the liner and or whatever needs replaced. Motor works great just need to freshen up the pump. Just do not want to tackle the bearing if I dont have too. Plan on selling it as soon as I fix it up.

 

[Newriver]

I think i see some of the problems. Looks like someone has put a U-2 pump on the 90 model suzuki that should have a U-4. Because it has the non flanged liner as seen on the skematics on outboard jets web page. Maybe maybe not. The motor was a factory jet. Model DT 40 PU. Anyone know if they put the U2 pump on that model? I think I'm going to visit this "buddy" of mine that sold me this and smack him in the mouth.

 

[Darkside]

I think i see some of the problems. Looks like someone has put a U-2 pump on the 90 model suzuki that should have a U-4. Because it has the non flanged liner as seen on the skematics on outboard jets web page. Maybe maybe not. The motor was a factory jet. Model DT 40 PU. Anyone know if they put the U2 pump on that model?

It is possible that back in 1989 or 1990 they were liminted in the models they offered or used parts from the U2 until the U4 was completely developed. I've seen crazier things. I would also think the missing plastic driveshaft sleeve would allow enough wobble in the impeller to scrach the liner. If the liner is gauged at 1/32nd and the plastic sheeve is 1/32 thick or thicker, I can see the centrifical force turning the blade to liner tolerance to near "0" as the drive shaft spinns the impeller up to speed.

Liners are fairly cheap, so is the plastic sleeve. Sounds like you will be whole again after $50 and some shipping.

 

[Newriver]

Thats my plan and see how it does. I just may have to keep it. Thanks Darkside. Maybe I'll hold off on the punching my buddy.

 

[ramuh2121]

Does anyone know how many washers I should have on a model Z medium pump ('86 40HP Yamaha motor)? I got the pump used from a guy down in SE MO and it only has 4. Two on top, two on bottom and then the nut-saver or whatever it's called with the tabs. When I look at the parts diagram on the OBJ website, it shows 8 washers.

I checked the clearance when I first mated the motor and pump and from what I could tell, it was pretty darn close to 1/32, but I'm a nube, so hard to say for sure. I need to check it again as I'm trying to squeeze as much performance as I can out of my Yamaha 40/30 on my 18' sled.