I just had my 318 rebuilt all new parts with 360 heads started it up today for the first time and with in minuets it reached 190 degrees and I shut it down.I put a fan at the front and tried again and the same thing happened.The timing is set at 10btdc.I don't no y its overheating any ideas?

 

Depending on how you filled the water it could have an air pocket. On small blocks, the first fill I do with a funnel and short hose at the water pump heater hose and wait till the water comes out the heater hose fitting at the intake manifold crossover passage. This shouls assure complete block fill. Drilling a small hole in the thermostat can help too, some new style ones have this provision already.

 

The thermostat has been drilled so when I fill the water goes all the way with out opening the thermostat.So im scared to run it over 190 d to see if the temp stops.When I ran the engine I had the cap off the hole time would the cap make a differance

 

Im running stock rad and shroud that came with the car in 1972.The rad has been checked and cleaned.Im all so running a 6 blade flex fan about 3/4 from the rad.A new water pump alm.Im not driving the car just running in park so i can check for leaks and set timming.Its at 10btdc at 1,000 rpm and about 30btdc at 2,500 rpm.The thermostat is a 180d.

 

190* is not hot.. are you sure its a 180* stat I would run it longer and shut it down if it goes over 210 and yes the cap also bring the boiling temp up. Are you running just water or 50/50 mix this also helps keep it cooler.

 

Its a 180 and im running 50/50 mix Should i try putting the cap on and running the engine again and see if it stops rising.

 

roland -

Ah yeah, 190* should be about right.

You need to find out what size thermostat you have (I believe 190* was fairly common.) If you have a very efficient radiator, you can drop to a 160* stat, but right now I don't think you should have anything to worry about.

If you're really nervous, there are "wet water" compounds, I think Royal Purple sells one, that you add to your coolant and can drop the temp by 10 - 15 degrees.

Archer

 

The first time I ran it went to 200d and I shut it down the second time it went to 190 and I didnt let it go any higher.Maybe Ill try some additive and put the cap back on and run it and see what happens.THANKS Ill keep ha'll updated

 

roland -

If this is a new occurrence and the engine heats up fairly quickly and linearly, then your T-stat may have locked shut. (It wasn't a Mr. Gasket Hi-flow was it - they really suck ???) Believe it or not, I've had the best luck with the stock "STANT" replacement T-stats.

A simple test would be to remove the t-stat and see what happens. The you can replace it with a new one and/or a lower temp one, if you like.

Note what I said about having an adequate and properly functioning radiator. That can be tested with an IR thermometer or by "feel" (be careful), looking for cold spots.

Archer

 

YES! the cap makes all the difference in the world. the car WILL get hot quickly with no cap. fill the system up, put the cap on, and try it again.

 

Should I be running an resurulation system?Write now I just have a overflow tube.

 

In 72 some did some didnt... I would put an overflow tank just to be safe/ eco friendly. NO im not a tree hugger. but if it does lose some it will pull it back in as it cools. antifreeze/coolant is expensive why waste it?

 

I just ran it again with a new rad cap and toped the coolent.I ran the engine at 2500 rpm for about 10 minuets and then the engine would go down to 1500 and then go up to 2500 again it did that off and on.Then I put it at 1000 and it cut off.I started it again it seemed to be ok but the temp went to 210.I also notice that the thermostat housing was starting to leak.I don't no what to do now.All this was done in park out side.

 

roland -

Take the old thermostat out, remove all of the old gasket material from both sides and make sure both sides are clean and dry.

Get a new STANT t-stat, try a 160*, and reassemble with ample Permatex gasket maker (the one for water seals).

Let is set OVER NIGHT, and see what happens.

If the engine still over heats, sitting in park, take it out for a drive (highway). It should cool right down. If it does, get a bigger fan or do something to increase the air flow (cooling).

If it still gets hot while driving at speed, you have a coolant blockage somewhere. May need to do a flush.

Just remember 190* - 210* ISN'T hot. if it approaches 230* get worried. That assumes your guage / sending unit are working correctly. That too is where an IR thermometer can come in handy.

I've been through this myself, and while it ain't fun, there really are only a few thing it could be.

The above assumes your air/fuel mixture and timing are set correctly.

Archer

 

Archer,
I'll give that a shot and see what happens.I also notice that the lower rad hose doesnot get as hot.What do you think about the rpm changing like that?Im running a new auto meter for water temp.

 

make sure your radiator isn't partially plugged up. i was working on a chevy truck that would stay cool then over heat really quickly. turned out that the upper radiator was completely clogged up.
also take your t stat and put it into a pot of boiling water and make sure it is opening up.

 

i would stay away from the 160 stuff. stick with the 180 tstat.

 

Flex fans are garbage... and dangerous. A new engine will be tight and run a little hotter for the first few miles

 

Im going to try a alum rad and a clutch fan and see if that helps.