New 360 Crate motor running Hot - 210-215 degrees

[Johnny Cuda]

Hey it's me again with the same problem I've had since I put my new 360 Crate Mag Motor in last fall. I'm still running at 210 to 215 degrees and I can't figure it out.

Here is what I can tell you,

I've got a 195 Degree Thermostat, Radiator is 4 Core 26". After driving at 210 degrees when I turn the car off and check things the upper radiator hose is ROCK solid and extremely HOT. The lower radiator hose is cool to the touch. (i have a wire coil in the lower hose to prevent collapse)  The upper portion of the radiator is extremely HOT and the lower part of the radiator is cool to the touch. I'm not sure if the Water Pump is bad (new and came with motor) or if my radiator is messed up or what. Also when I pinch the upper radiator hose at idle I do not feel a surge when I let go. Would a 180 dgree thermostat be better??

I'm very fustrated cause I feel like I am slowly destroying my new motor. Any help or advice would be greatly appreciated. I don't want to go tearing into things until I get a better understanding of what is going on.

Thanks

[MEK-Dangerfield]

If it was a bad water pump, I would think it would overheat real fast. Do you ever boil over? If not, it sounds like a blockage in the radiator.

  Mike

[Bullitt-]

  Bet you have a bad t'stat. that has failed in the closed position, what you describe is no circulation whatsoever.Water pump would have to have a broken impeller or impeller shaft which is unlikely on the new crate motor. I recomend you get a failsafe t'stat, Autozone lists them but you may have to order.  

[Rob C]

Agreed, blockage in the rad after a problematic T-stat.

[Johnny Cuda]

Mike,

I don't seem to be boiling over, but it's hard to tell since I've got a reclaim bottle.

Bullitt,

I recently replaced the original thermostat with a Superstat Heavy duty one. Symptoms and temperature were the same with both thermostats.

It is kinda odd to have the upper hose Rock solid, I would think if you squeezed it hard enough something would either flow into the radiator or back to the block, although when the engine temp starts to drop below 190 degrees or so the hose become flexible.

Thanks for the suggestions,
John

[daves70]

Sounds like a radiator problem to me if your sure the t.s. is good. I'd check for blockage.

[Bullitt-]

   The reason you hose his hard is steam/pressure. With the motor cool remove the radiator cap, squeeze the upper hose & you should see the coolant come up & out the radiator.neck.  Take you lower radiator hose off & see how fast the coolant runs out. Maybe run some water thru it. If it comes out pretty fast blockage isn't your problem. I did see this once in a '69 302 Z28 when we put in a new motor & started up after a while she started overheating, the problem was vapor in the block but that took just a few minutes to show up. I have seen it recommended that a small hole drilled in the t'stat flange will prevent this. Had you used this radiator with another motor w/o problems?   Also whenever & drain & refill a cooling system I leave the cap off & warm up the system. watch the coolant flow thru & keep adding till it won't hold no more. Once I did't & blew my head gaskets. 

[matt63]

How about running without a thermostat temporarily.  Also, I've wondered what happens if you put the thermostat upside down (almost did that once).

[Bullitt-]

 no/t'stat would elimintate tstat questions

[Bullitt-]

 pointy end up

[Johnny Cuda]

Bullitt,

I had the same radiator in when I had my 340 in it, didn't have any problems at all. I bought a 180 degree tstat last week I'm draining the coolant right now to put it in, might take the radiator out to see if it needs flushing but it's pretty new.

John

[dimples]

Will it cool down going down the road? Or does it permanently run at 210-215?
Might want to try a different guage?
Timing being retarded can cause the temp to rise too.

[DodgeFreak]

Did you make sure there wasn't any air trapped someplace it shouldn't be?? just a thought...

[Bullitt-]

The thing that scaring me about this is if there is no coolant in the intake for the temp. sensor to get a reading from you could actually be a lot hotter than 215. Air does not transfer the heat as efficiently as liquid. The only other thing short of a broken pump, and I admit I have no prior knowledge of this, is they could have plugged the lower pump with something for shipping that should have been removed. I would not drive this until you get resolve. GOOD LUCK!

[Chryco Psycho]

advance the timing at idle , where is it set now ?