stemper57301
Cadet
- Joined
- Jul 19, 2010
- Messages
- 24
Ok, it's back to the boards with my outboard! The motor is a 1974 johnson 40hp (40rl74) this is just a guess since there are no numbers on the engine (as discussed in my previous post). The impeller i purchased was for this model and it was the replacement, also the diagram seems to match that model. I know that with all the skilled people in this forum I can get this baby figured out. 2 months ago I changed the water pump impeller, just as a maintance thing, it pumped water fine and never got hot. After the impeller change it cooled fine up untill about 3 weeks ago.
So here is whats going on, in a barrel it pump some decent water out of the exhaust ports on the back of the leg. It runs at about 120-130 at idle running for about 20 minutes. All seems well so I headed to the dock to check it out. Again idle temp is fine and water is flowing. When I accelerate it goes from 120 all the way to 165 where i shut down at to avoid problems. Also after I go WOT and back down to idle it seems to lose water flow out of the exhaust ports, and will get hot at idle.
What I have checked and tried:
-Compression Test - 100psi in each cylinder (so it didnt get too hot)
-Pulled LU and checked water pump impeller and water pick-up tube for blockage and problems.
- Hooked garden hose up to water inlet tube and water flushes FAST from exhaust ports.
Upon checking I noticed the water inlet tube grommet was shot and have ordered a new one. I also noticed that when I chaged the water pump I broke a screw on the water pickup plate so it didnt pull tight to the LU kind of popped up on the side towards the exhaust. Would this cause the water to not flow from the pickup fast enough to not get pulled in by the impeller?
Thanks for all the help in advance!
So here is whats going on, in a barrel it pump some decent water out of the exhaust ports on the back of the leg. It runs at about 120-130 at idle running for about 20 minutes. All seems well so I headed to the dock to check it out. Again idle temp is fine and water is flowing. When I accelerate it goes from 120 all the way to 165 where i shut down at to avoid problems. Also after I go WOT and back down to idle it seems to lose water flow out of the exhaust ports, and will get hot at idle.
What I have checked and tried:
-Compression Test - 100psi in each cylinder (so it didnt get too hot)
-Pulled LU and checked water pump impeller and water pick-up tube for blockage and problems.
- Hooked garden hose up to water inlet tube and water flushes FAST from exhaust ports.
Upon checking I noticed the water inlet tube grommet was shot and have ordered a new one. I also noticed that when I chaged the water pump I broke a screw on the water pickup plate so it didnt pull tight to the LU kind of popped up on the side towards the exhaust. Would this cause the water to not flow from the pickup fast enough to not get pulled in by the impeller?
Thanks for all the help in advance!