very minor issue that has been bugging me. the temp in my rig gradualy gets warmer and warmer the longer it runs at speed. not over heating but at some point it will.

both are 350s and have the same carb, exhaust, radiator, flex fan on a solid mount and tranny
old motor: stock long block, water pump,1st gen performer intake[1970 somthing]
temp was rock steady winter, muddin, summer, slow wheeln didnt matter.

new motor: rebuilt +.020, stock heads, roller rockers, rv cam, timing gears, weiand aluminum water pump, hv oil pump, performer intake [newer model], accel dist.

the rad flushed out before the swap, i belive the tstat is a 160.

would a electric fan, bigger flex fan, or ????? where to start.

Are you running a fan shroud?

A 180 degree stat might help. I hear it holds the fluid in the radiator longer and gives ita chance to cool better.

yes on the shroud, and i was thinking the same way on the tstat

Sounds like a very small leak and system can't hold pressure too me! 160, or 180 thermostat won't change the amount of flow. Could also be a mis-firing cylinder, look at the plugs, ohm out the wires....? I'd really check to make sure your holding pressure. A radiator shop could confirm this.

Check the lower rad hose and make sure it still has the spring in it.

Check the lower rad hose and make sure it still has the spring in it.

huh????

i cut the old one up to make a sleeve for the new one so it didnt chafe the frame, didnt notice a spring.

the performer i have now was a little corroded at the tstat and does leak a very small amount, that could be it.

huh????

i cut the old one up to make a sleeve for the new one so it didnt chafe the frame, didnt notice a spring.


If the spring in the lower hose is missing or broken the hose can collapse. That slows down flow to the rad which makes it overheat.

its a new set of hoses, where would the spring have been. i split the old one length wise and wraped it around the entire length of the new one.

while the engine is "COLD" just grab the lower hose and squeeze it, if it collapses then you don't have spring in it. it very well could the trouble.
second thing, how old is the water pump? if its older then heck your impeller could be so corrorded that its not moving water at a good rate.
3. check you antifreeze setting it should around -30 even if your in the southern part of the US. the mix keeps it from boiling out, and if its to rich or pure antifreeze then it won't absorbe enough heat to keep the engine cool. the gauges will say its 240 but you can reach in and put your hand on the hose and radiator.

its about 4 years old bout has only been put on in november 04 and has 4000 miles on it

I could never keep my motors cool with the stock stuff. no idea why, but I never could get them to run as stock. big block 4 core radiator did the trick. also took the mechanical fan off in favor of electric fans. one more thing you don't have to take off the motor when working on it. also with an electric fan on a thermostatic control your motor will get up to temp faster than with a solid mounted flex type fan, much like a clutch fan.

-Scott

Airflow isn't your problem because it cools well mudding and ideling.

You need a bigger radiator. Because your new motor puts out more power then your older one it also puts more heat into the water.

I would definately put a radiator shroud on it, after fixing any leaks and installing a NEW? thermostat. I have had very good luck with the twin-1" core aluminum radiators that you find from Summit or around on ebay. They can be had for less than 200 for a brand new one.

allright i got enough suggestions ill spend tommorrow sorting it all out. thanks for the many good responces. ill let yall know

What did you find out?

well i finaly got around to dicking with it and solved it by accident. i kinda gave up on it and was adjusting the timing and mixture[idle] and it went away. i drove it 45 miles to a mud bog comp and it never got above 180 ish [ a no ### gauge so i cant call it exact] and ran like a top.