another heating issue

[ringmaster]

i have a 1979 sea ray with a pre alph outdrive 233 mercruiser. last year it ran at about 100-125 all day long this year i had to take the manifolds off and replace the gaskets. while they were off i cleand out alot of beach sand. in the process i found out there wasnt a thermostat so i got one after that it would run around 175-200 so i took it back out but it still runs 175 at wot. and idle it barley breaks 100. could it be the manifolds going bad or just bad. yes it has a new impeller that was the first thing i replaced when it started running hot and the thermostat is a 160deg.

 

[jerryb1]

Re: another heating issue

Not sure what engine you have, but i have a 1980 searay with a 260 V8 GM engine. It uses a 140 F thermostat.

 

[ringmaster]

Re: another heating issue

its a 233 (351) mercruiser

 

[ringmaster]

Re: another heating issue

this thing is getting plenty of water so im not sure why its getting hot.

 

[mkast]

Re: another heating issue

The condition of the engine driven water pump?

 

[ringmaster]

Re: another heating issue

the water pump is working fine

 

[arks]

Re: another heating issue

Closed cooling systems typically use 140 t-stat's, and raw water cooled engines use 160's.

 

[ringmaster]

Re: another heating issue

its raw water cooled and had a 160 but i had to take it out.

 

[ringmaster]

Re: another heating issue

ok i just spent most of the day back flushing everything i could think of. i havent tested it yet cause i want to get another thermostat and try agian. if it still does it what would be the cause? i just dont understand how i could go from running 100 last summer to running 175 this summer and all i changed was the impeller.

 

[sarantis]

Re: another heating issue

Did you use the right gaskets at the manifolds to the elbows?
Using clear plastic hoses will help you a lot to find out what is going on.

 

[ringmaster]

Re: another heating issue

yes i did im going out now to see what it does im not sure what to think

 

[ringmaster]

Re: another heating issue

ok i just got back and no better. i took the intake hose off at idle and the water is barely comeing through it from the out drive. now the impeller is brand new. i dont know what would be doig this and why. tomorrow if it isnt raining im going to take the whole out drive off and start there and see if its blocked some where in there.

 

[sarantis]

Re: another heating issue

Before take the outdrive out bend down and check the hose from the bell housing to the transom .if it's ok take out first the lower unit and check the rest of water route by using a hose garden

 

[ringmaster]

Re: another heating issue

ok took outdrive off and there are no blocks. what i did find on closer inspection is the 2 halfs of the impeller housings are so warped they dont even mate up. im pretty sure thats the problem. for 50 bucks i hope so.

 

[ringmaster]

Re: another heating issue

ok i got it all back together and it works. double checked the temps with a infered gun and its all within specs.