Rebuilt Engine Breakin ??

johnny · Post by **johnny** » Mon Oct 18, 2004 8:34 pm

While running my freshly rebuilt 318 poly to break in the cam, the temperature gauge is really climbing. I know newly rebuilt engines tend to run hotter due to the additional friction, but mine is getting too hot to run it for long (truck is stationary). I removed the t-stat, but no difference. It has a new water pump with the stock non-clutch fan setup. Would switching to a flex fan or something that pulls more air than the stock fan help? Thanks.

Post by **POWWAG** » Mon Oct 18, 2004 8:56 pm

Things that can cause an engine to run hot when its not a cooling problem.
1) Retarded, is your timing set right?
2) Lean, big vacuum leak?
3) Weak valves, are your valves set right?

Don

Website · Post by **wideblock** » Tue Oct 19, 2004 12:30 am

might try putting a large fan in front of the truck before you let it run sitting still for too long. it might just be an air flow problem.

Butch Romig · Post by **Butch Romig** » Tue Oct 19, 2004 7:49 am

PLUGGED RADIATOR

Johnny · Post by **Johnny** » Tue Oct 19, 2004 8:48 am

radiator was boiled out and cleaned, so I don't think it's that. Timing is set correctly, has hydro lifters, and seems to run nicely, so I don't think it's a vacuum leak or valve problem. I'll try putting a big electric fan in front. Thanks.

Jeffc · Post by **Jeffc** » Tue Oct 19, 2004 10:51 am

are you sure that it is running too hot? regardless of what the
temp gauge say's have you checked the temp at the
radiator with something that reads temp independent of
the temp/sender gauge.....
of course if it's puking coolant, that would mean it is running
hot; maybe the water pump is not working right and/or has blockage somewere.
When you rebuilt this engine did you check water pump
clearance to the timing case? used or rebuilt pumps
(even new pumps) may have the wrong clearance and
may not do there job right.
You pulled the Tstat and it's still running hot? even from a
cold start?
There are a number of other things that can cause it to run hot,
many covered by others already, then again I have seen some
strange stuff over the years, like, rats making a nest in the tailpipe
when a engine is out for a rebuild...

Johnny · Post by **Johnny** » Tue Oct 19, 2004 4:06 pm

I haven't checked temp at radiator, but it was starting to blow coolant out the overfill port and the dash temp gauge indicated it was running at the 3/4 mark. I bought a mech. temp gauge to install and verify.

I didn't check the water pump clearances - never thought of that! Temp. gradually increases as the engine is running, rather than suddenly.

Hmm, I guess I better check the exhaust pipes for rodent's nests! Thanks.

mesman · Post by **mesman** » Tue Oct 19, 2004 5:41 pm

i'm sorry guys, but the comment about the rat in the tailpipe makes me think of the story about the gerbil in the jokes section! *mental image* a flaming rat being catapulted out of a tailpipe!

1966D100 · Post by **1966D100** » Tue Oct 19, 2004 5:53 pm

ah man, anything but that story again, my sides still hurt from laughing!! LOL

"....it was the only way i could get him out.....i lit a match to see if he would be atracted to the light....."

LOL!!!! *crys from pain* Oh thats classic!!!

Butch Romig · Post by **Butch Romig** » Tue Oct 19, 2004 8:32 pm

a radiator can be "boiled out" ,and not be clean!,the only way to be sure that it is clean is to have it rodded out
butch

johnny · Post by **johnny** » Tue Oct 19, 2004 9:45 pm

however, I did have the rad. shop boil it out, rod it, and pressure test it. I believe the radiator is in good shape.

Sweptline.ORG

Rebuilt Engine Breakin ??

Rebuilt Engine Breakin ??

Well,

Jeff,

You're right, Butch,