Guys/Gals,
I started a post on this a while back but I think something happened to it so I'll start from the beginning.
92 90HP Force 24 ft pontoon boat
Had my impeller chagned 2 yrs ago. on the lake 3-4 times since. right after I had the impeller changed I took the boat out. overtemp alarm went off at low speeds. this happened again the next 2 times out as well, right off the dock.
I checked thermostat. NO THERMOSTAT. Put in a thermostat kit and installed a water pressure guage.
Ran motor in tank for 3 15 minute intervals.
1100rpm got 1-2psi
2000rpm got 6psi
3000rpm got 10psi
water and steam coming out of two exhaust holes on leg.
I thought good!
Took the boat out this weekend. right off the dock after idling for 3-5 minutes or so. no pressure and over temp alarm goes off AGAIN!. I shut off and wait. turn back on and get moving.
at 2000rpm getting about 2psi
at 3000rpm 3-5psi(lower than in the tank)
at 5200rpm(WOT)get up to 12psi but slowly the pressure backs off to 6psi or so.(this I don't understand)
If I dropped back to idle(900-1000rpm) pressure went to 1psi sometimes none
never got the overtemp alam again but I didnt idle very long again, on purpose.
I've thought of 3 things
1. slight blockage(pebbles, something) somewhere that at low speeds water pressure isn't enough
2. water tube isn't aligned correctly inside lower unit
3. impeller is bad(but why would I get 12psi at WOT)
4. maybe water pump seal causes some issue at lower speeds(could this be the case?)
I've never taken off LU, replaced impeller or water pump myself but I guess there is always a first time.
before I do that I was wondering if anyone had any thoughts?
regards,
I started a post on this a while back but I think something happened to it so I'll start from the beginning.
92 90HP Force 24 ft pontoon boat
Had my impeller chagned 2 yrs ago. on the lake 3-4 times since. right after I had the impeller changed I took the boat out. overtemp alarm went off at low speeds. this happened again the next 2 times out as well, right off the dock.
I checked thermostat. NO THERMOSTAT. Put in a thermostat kit and installed a water pressure guage.
Ran motor in tank for 3 15 minute intervals.
1100rpm got 1-2psi
2000rpm got 6psi
3000rpm got 10psi
water and steam coming out of two exhaust holes on leg.
I thought good!
Took the boat out this weekend. right off the dock after idling for 3-5 minutes or so. no pressure and over temp alarm goes off AGAIN!. I shut off and wait. turn back on and get moving.
at 2000rpm getting about 2psi
at 3000rpm 3-5psi(lower than in the tank)
at 5200rpm(WOT)get up to 12psi but slowly the pressure backs off to 6psi or so.(this I don't understand)
If I dropped back to idle(900-1000rpm) pressure went to 1psi sometimes none
never got the overtemp alam again but I didnt idle very long again, on purpose.
I've thought of 3 things
1. slight blockage(pebbles, something) somewhere that at low speeds water pressure isn't enough
2. water tube isn't aligned correctly inside lower unit
3. impeller is bad(but why would I get 12psi at WOT)
4. maybe water pump seal causes some issue at lower speeds(could this be the case?)
I've never taken off LU, replaced impeller or water pump myself but I guess there is always a first time.
before I do that I was wondering if anyone had any thoughts?
regards,
