low temps with crossovers
 

I am having the same problems with low operating temps on my 454's. Just changed thermastats to 160. Engine's run around 100 degrees and I know thats way too cool. The therm. housing has this spring and plastic 3 fin diverter inside. Don,t know much about this type of setup. How can I get the temps up without buying new recirulating pumps and all the harware? I do not have a bypass and do not seem to have pressure problems.

Re: low temps with crossovers
 

Is there any water flow thru that engine when the thermostat is closed?

Re: low temps with crossovers
 

Been out on the river all weekend and boat running good. It seems to be putting water through engine . You can feel water going through the small hoses at therm housing. Ran boat at 4000 rpm for 30 min. crossing lake and the highest temp got was 105.

Re: low temps with crossovers
 

What cross over and motor do you have???

Re: low temps with crossovers
 

Are your exhaust manifolds even getting warm?

Maybe something stuck in the thermostat keeping it open? I had the small cork gasket that goes on top of the thermostat slip out of place on reassembly and cause a similar problem, but to a lesser degree. It just took longer to warm up than my other motor.

Maybe a defective temp sending unit?

Re: low temps with crossovers
 

Don't know what kind of x-over. The exhaust manifolds are getting warm but certainly not too hot you cannot leave your hand resting on it. I have changed both temp sending units. When at house on the muffs, running 1000 rpm I checked exhaust water temp and it was around 105 degrees.

Re: low temps with crossovers
 

forgot, the engines are 1989 mark 4 454's built with larger cam, crane roller rockers, gil headers, weiand single plane, 850 double pumpers. Boat is a 1991 30' Baja Sport.

Re: low temps with crossovers
 

Thermostat stuck open?

Re: low temps with crossovers
 

Both brand new from C P performance.