pine island fred
Lieutenant Junior Grade
- Joined
- Dec 20, 2002
- Messages
- 1,144
This fix might have been discussed before and I missed it so I thought I would throw this out there.
Been an on going problem with a friends 90, 200 hp. 2 stroke. Motor started overheating and the first attempt to fix was naturally an impeller. He said it looked good and replaced it anyway like we all would. That did not fix it and this is where the pulling the hair started. Would overheat, then run normal for awhile, no rhyme or reason. Peed out the witness hole real good so we figured there was good water flow. New thermostats, pressure relief valve,taking the heads off and using acid, still overheated! I talked him into removing the thermostat houseings , running the motor and seeing what kind of water was running thru the blocks. Well there was none, just steam and the pee hose was running strong.
We dropped the leg to see if he might have missed or damaged the discharge pipe when he last installed the leg but that looked good and we used a garden hose to spray up the pipe and found good water flow. We took the pump apart and something did not look right.
Inside the plastic pump housing is an eccentric stainless steel cup or insert that the impeller rides in. About 1/4 around the circumfrance of the cup is a beval to allow the water out of the pump. The cup had actually rotated in the housing to a point where it locked up in the eccentric to severely restricted water flow. Was enough to pee real good out the hole but that as far as the water that made it by would go. The cup has 2 bent up tabs , 90 degs. apart that index into the housing base. The pump housing had 2 receptical for these index tabs that are 180 degs. apart. The old cup was so damaged removing it from the housing that he bought a new one and a new pump housing that has the correct index holes.
Watching him install the pump over the impeller , he used the method of rotating the housing over the impeller in the direction of rotation where as I push the vanes into the housing. I guess either method works but sure enough on looking down the discharge pipe, the the cup had rotated enough to block off the discharge. No-see-ums jumped us so we had to call it quits but I am certain that once installed correctly the overheat problem will be rectified.
Sorry for being long winded, wanted to share this while it was still fresh in my mind. regards FRED
Been an on going problem with a friends 90, 200 hp. 2 stroke. Motor started overheating and the first attempt to fix was naturally an impeller. He said it looked good and replaced it anyway like we all would. That did not fix it and this is where the pulling the hair started. Would overheat, then run normal for awhile, no rhyme or reason. Peed out the witness hole real good so we figured there was good water flow. New thermostats, pressure relief valve,taking the heads off and using acid, still overheated! I talked him into removing the thermostat houseings , running the motor and seeing what kind of water was running thru the blocks. Well there was none, just steam and the pee hose was running strong.
We dropped the leg to see if he might have missed or damaged the discharge pipe when he last installed the leg but that looked good and we used a garden hose to spray up the pipe and found good water flow. We took the pump apart and something did not look right.
Inside the plastic pump housing is an eccentric stainless steel cup or insert that the impeller rides in. About 1/4 around the circumfrance of the cup is a beval to allow the water out of the pump. The cup had actually rotated in the housing to a point where it locked up in the eccentric to severely restricted water flow. Was enough to pee real good out the hole but that as far as the water that made it by would go. The cup has 2 bent up tabs , 90 degs. apart that index into the housing base. The pump housing had 2 receptical for these index tabs that are 180 degs. apart. The old cup was so damaged removing it from the housing that he bought a new one and a new pump housing that has the correct index holes.
Watching him install the pump over the impeller , he used the method of rotating the housing over the impeller in the direction of rotation where as I push the vanes into the housing. I guess either method works but sure enough on looking down the discharge pipe, the the cup had rotated enough to block off the discharge. No-see-ums jumped us so we had to call it quits but I am certain that once installed correctly the overheat problem will be rectified.
Sorry for being long winded, wanted to share this while it was still fresh in my mind. regards FRED