motor heating up at higher rpms

J

jasonh1972

Member
the motor runs fins at full throtle but after a few minutes the engine starts to heat up a little to much and then i back it down and it colls back down again
the engine is a 72 mercruser 188
i did notice there is a 1and a half inch hole in the flex hose going into the lower unit could this be a problem??
 
sounds like your flow is being restricted somewhere, follow the loop. Including poss bad t-stat
 
Also check your heat exchanger. I know that the early 3.7L's came with a smaller heat exchanger that had problems with overheating. Also how old is your exhaust elbow where the raw water dumps out? If it's more than 3 years old it may be getting blocked up. Check for leaks first, and then look for flow restrictions. Also check your impeller in the outdrive, they are known to spin the hubs at high RPM's.
 
188's are 302 Ford engines, make sure the belts are OK, if the belts get loose on a ford, the engine will over heat at higher rpms. Obvioously, check the impeller in the lower unit if the problem persist
 
spareparts said:
188's are 302 Ford engines, make sure the belts are OK, if the belts get loose on a ford, the engine will over heat at higher rpms. Obvioously, check the impeller in the lower unit if the problem persist
Click to expand...

Spare is right, I was thinking the 488 4 cylinder. My bad guys, I'll take my beatings now.
 
thanks for the help guys i got the impeller done but the trick was to get the shift linkage hooked up right the first time i thought i had it was all reverse the second nothing the third lower unit wouldnt go on the last time an employee i call rusty bucket thought it would be easier to just go in from the transum side of the lower unit to line up the shift linkage
 
You must log in or register to reply here.
Back
Top