water Temp

[pbuzz3323]

Hve the 5.0 MPI with the water sending unit on the thermostat...I finally got all the system hooked up...Riseres and all...Ran it on Muffs and Tempo went to 140 and dropped...A good sign I guess... Put it in the water to run and ran for 1/2 Hr but the Temp neverwent past 100 degrees..Im hoping its the sending unit from the housing....im also hoping that it wasnt running cold the whole time but i assume it wasnt because it ran fine..Any suggestions other than no thermostat( thats is Installed)? like i said..on muffs went to 140 and dropped..in water...stayed at 100....Both hoses from thermo housng were kinda warm and engine block did get hot. so did the ports for the exhaust/water exhaust...Then afterplacing boat at mooring an debarking...got into dingy and flipped it..i nearly drowned but thanks to others I was ok......Damn water was colddddddddddddd

 

[Don S]

Re: water Temp

Get an IR temp gun and take some actual engine temperatures and compare it to the gauge.

 

[pbuzz3323]

Re: water Temp

Would you change the sending unit now as well?

 

[jluchuk]

Re: water Temp

I happen to see your problem with water temp. If this is a Volvo engine, when you pull the thermostat housing to change the thermostat, you may want to check to see if the lines and the small internal bypass hole is clogged. I just had a similar problem on my 5.0 GL and this was the problem. You cannot see the clog and have to push a screwdriver or wire through the port holes to insure they are clear. You can also try to push water through the housing with a hose and water should come out of all ports. Don't ask why the engine will run cold when the water way is clogged because it does not make sense but it does fix the problem. Good Luck
Jerry

 

[Don S]

Re: water Temp

I'm afraid your Volvo thermostat housing with 4 hoses is completely different inside and out of his Merc 5.0MPI 6 hose setup.