85 8 hp seahorse overheating, steaming

[juldog]

83 8 hp seahorse overheating, exhaust exiting water indicator. After 5 minutes of operation, loss of power, steam coming<br /> out of rear of engine. I have replaced head gasket, and checked impeller. It looks to be almost brand new. Lots of back<br /> pressure on pipe going to engine if I apply water pressure to it. Could it be that ports are clogged in engine or pipe may be<br /> clogged with silt etc. Also, can pipe going to engine be removed without removing engine from support. What should I check<br /> next?

 

[papasage]

Re: 85 8 hp seahorse overheating, steaming

check your theromastat.the plate under your pump could be worn

 

[juldog]

Re: 85 8 hp seahorse overheating, steaming

Actually the thermostat had been removed before I got the motor. It runs good even when cold, just heats up too much. I checked water pump components, look okay, like it was sealing good. I didn't really know what I was looking for. Is my primary concern that water was bypassing the pump at the plate?

 

[jim dozier]

Re: 85 8 hp seahorse overheating, steaming

Replace the impeller anyway. Check the impellor housing and plate for damage, even a little. Remove the thermostat cover and while the water pump is off, back flush the system from the thermostat back to the pump with a garden hose and maybe even some compressed air to make sure its clear. I have seen posts here by those in the know that on some engines the water tube gromet at the top where the powerhead joins can get screwed up and block the coolant passages. For one reason or another it sounds like a blockage, but I would replace the water pump anyway.

 

[papasage]

Re: 85 8 hp seahorse overheating, steaming

some times just replacing the rubber impellor doesnot do it you may need the whole kit . the plate under the impellor could be worn . had that problem with a 40 hp .

 

[juldog]

Re: 85 8 hp seahorse overheating, steaming

St. Pete you win! Checked the grommet at the powerhead. Apparently, the guy before me got it real hot. and melted the grommet down into the top of the copper tube when the water pump went out. He replaced the water pump assembly, but the grommet restricts the flow down to a 1mm diameter hole. Once I dig the old broken bolts out of the block, I think I'll be back in business. Thank you to ALL for the help.