Well thanks to Frank and his step by step directions, I was able to replace the water pump assembly in my 88 force 85 hp. All went smooth for the most part and the most difficult parts were getting the impeller lined up with the key in the housing and getting the lower unit back on so the splines match up. One question I have however - I didn't notice if the spinning the drive shaft by hand was difficult to do before I replaced the waterpump, but after (while trying to align it when reinstalling the lower unit) it seems to be very difficult to do. Is this normal???
Thanks
Re: 88 Force 85HP thanks Frank, replaced water pump
From what I've learned, it sounds like you've either put the impeller in with the blades curved in the wrong direction or you're turning the drive shaft in the wrong direction.
Re: 88 Force 85HP thanks Frank, replaced water pump
Odd, cause I followed Franks step by step instructions and greased the housing with soap then set the housing over the impeller and twisted in a counterclockwise direction. The impellers blades were all bent and looked good. Could it be that I didn't put enough soap? I haven't fired it up yet. plan on tomorrow morning.
Re: 88 Force 85HP thanks Frank, replaced water pump
The impeller takes about 15 horsepower to drive at 5000 RPM, so yes, it is difficult to turn by hand. Remember: those bent blades are rubbing against the housing AND you are trying to deflect them even more as you turn the drive shaft.
Now the question comes up "Why don't they wear out while the engine is running?" Well, run the engine out of the water or without muffs and in about 30 seconds you will have a ruined impeller. Maybe!
See: With the engine in the water or on muffs, the resistance of the water actually bends the blades away from the pump housing and the impeller acts like a centrifugal pump. The impeller blade tips only touch the pump housing when dry, at very low speeds, and when the engine is stopped. This is why I like the OMC pump and impeller better: The impeller is much larger in diameter and has much greater centrifugal pressure. It is just a better design.
Re: 88 Force 85HP thanks Frank, replaced water pump
I have an 88 Force 85HP also and I drove the boat from our property to the mainland (10 minutes), put it on the trailer and brought it home. When I tried to fog the motor in the driveway I could not get any water to flow out of the exhaust port. I used a tub with water high enough to cover the intake louvers that suck the water in and then I tried it with muffs and both times no water was pulled into the motor to cool it. Am I doing something incorrectly or did I damage the water pump trailering the boat home (4 hour journey)? any information would be appreciatd - Thanks.
Re: 88 Force 85HP thanks Frank, replaced water pump
Did you leave it running on the way home??? LOL , just kidding, sometimes it takes a little bit for the motor to get the water to flow, so you might want to give it some time.I guess it was flowing on the last trip on the water? Post back with what you find. MOPARMAN ROLL TIDE
Re: 88 Force 85HP thanks Frank, replaced water pump
Mopar man - thanks for getting back to me. I did not leave it running on the way home but maybe I should have. I ran the motor long enough for the panel where the exhaust passes thru under the cowling to get hot to the touch and still no water. I think I am going to take it to a local lake this weekend and try running in the water again. not sure what else to do except change the impeller - could it have anything to do with the thermostat?
Re: 88 Force 85HP thanks Frank, replaced water pump
You should start your own thread - but in any case, if you run it in a tub, i think you need to have enough water in it to go up past where the water pump is from what i've been told so you need a pretty big tub to do this with. I use a 4 x4x2' tub and fill it all the way up and the water line goes right up to the anticavitation plate. I never had luck with getting muffs on correctly enough to feel ok with running the motor. Also could be that your t-stat is stuck - take it out and put it in a pot of boiling water to see if it opens. should be a 110 degree t-stat. When was the last time you changed out the impeller? Most indicate here that it should be done every 2 seasons or so.
Good luck
Re: 88 Force 85HP thanks Frank, replaced water pump
Thanks for taking the time to send an answer, i agree with you on both points about finding a tub large enough to hold enough water and that muffs just don't fit well on the gear housing. i will check the t-stat and see if is opening or not. I have never changed the impeller or t-stat and I have owned the boat for 9 years- probably a good place to start. I will try and put it in the lake this weekend and see if things don't funtion better there just so I can at least get it winterized. Then I will plan on changing the impeller and thermostat over the long winter season here in Minnesota. Thanks again.
Re: 88 Force 85HP thanks Frank, replaced water pump
If you haven't changed the impeller in 9 years, you definitly should - not a question. It's more of a maintenance thing than anything else. Its fairly easy to do (or at least i can say that since i did it successfully) Frank A. posted very good step by step instructions on this forum (sticky post) and you should also get a clymer or oem manual if you plan to do it yourself that is.
good luck
Re: 88 Force 85HP thanks Frank, replaced water pump
Don't mind if I but in. Just a comment on Frank's instructions, PERFECT! Don't even pickup a manual. Never did one on a Force before, 1 hour even with a broken bolt. Thanks Frank. O,T.
Re: 88 Force 85HP thanks Frank, replaced water pump
Thanks Further and OT - I will take your advice and change the impeller - How do I locate Frank's instructions on this thread? Further you mentioned 'sticky post' what does that mean?