Very bad feeling . . . Need serious help!

S_Beaudry · #1 (**permalink**) 05-04-2005, 08:27 AM

Got the neewly built 302ci running on the chassis, with a problem though.....

Within about 5 or 6 minutes of running from a cold start the coolant temp gets up to about 210 degrees or so with the fan on, without a thermostat installed though.

On the passenger side of the block, I can see an oval shaped imprint of (looks like) dirty water, not a puddle, just a wetness, about a foot away from the end of the header pipes, no sidepipes installed yet.

Out of the same side, there seem to be steam or smoke coming out of the valve cover cap opening.

Am I wrong in thinking either a bad head gasket or maybe worse, a cracked block?

Any ideas before I take her apart to check?

Everyone's opinion is valued with me......please help!

larryar · #2 (**permalink**) 05-04-2005, 08:50 AM

The first thing that i would do is put a thermostat or restrictor plate in. Without some restriction, the water moves too fast through the radiator for cooling.
Larry

relaxinrob · #3 (**permalink**) 05-04-2005, 11:14 AM

Larry is dead-on.....get a thermostat in there, then test it again.

mickmate · #4 (**permalink**) 05-04-2005, 11:23 AM

Even with monotorque gaskets I found the outside head bolts will loosen. Retorque them a couple of times.

C4 Cross Fire · #5 (**permalink**) 05-04-2005, 11:29 AM

Hey--what's the problem if I don't have a thermostat and it NEVER gets hot?

Mike Simard · #6 (**permalink**) 05-04-2005, 11:42 AM

Can you verify that you have coolant flowing through the block and heads? It might be possible to put a head gasket on the wrong way, the coolant flows through a passage at the end of the block and the gasket must have the corresponding hole there.
If you find water or steam inside the valve covers you may have a head bolt leaking, the threaded holes go right into the coolant so you must use a thread sealant.
Good luck!

trularin · #7 (**permalink**) 05-04-2005, 12:54 PM

Pressure test the coolant system.

Get a pressure tester and pump to 15 PSI cold. Let it stand over night. It should be 15 in the morning if everything is sealed.

Okay, so you test and it hold pressure, the water forming could, and I stress could, be condensation. The steam or smoke coming out of the breather could, and I stress could, be blow-by.

Pressure test works on cold engines, it is possible to have a thermal crack. One that opens when the engine gets hot. Seen many of these on GM.

It is possible you have a leak. Here is another one, fill the coolent system all the way up with a T'Stat. run the engine without stopping for an hour. Let it cool and check the level, if it is down, pull the plugs and check for water burning in a chamber.

Hope this helps.

Curt C. · #8 (**permalink**) 05-04-2005, 01:46 PM

Lets not forget that engines tend to run a little hot during break-in. Is your PCV system hooked up? Engines will smoke out of the breather with no PCV vacuum. Plus, all kinds of stuff burns off from a fresh engine build. Break it in futher and see if the engine temps go down after letting it cool then restarting. 210 on the water is not that hot.

S_Beaudry · #9 (**permalink**) 05-04-2005, 05:11 PM

Being a 1974 block, there is no pcv system......is this bad?

Ok, pulled the valve covers on both sides......

The passenger side has a couple bubbles of antifreeze in the left over oil in the head.

The cooling system has been presurized to 15psi for about 3 hours now and has NOT moved a hair.

Any new thoughts?

SVMCOBRA · #10 (**permalink**) 05-04-2005, 06:17 PM

Need more info on your 302. Is it carb or FI? Did you check to make sure the fan is running in the right direction? Did you have time to set the timming? Do you have the correct rotation water pump? If you are running a carb I say yes you need a PVC or at least some valve cover breathers. I would also double check to be sure your heads are torqued correctly.

Rick Parker · #11 (**permalink**) 05-05-2005, 12:05 AM

The first thing I would rethink is the installation of the head gaskets. One of the head gaskets has to be installed upside down directing the water between the block and the heads. If this is not done the water is not allowed to flow it's correct path. I think the one that has to be flipped is on the passenger (RH) side. It is stamped "FRONT" on one end. If it is not flipped the "FRONT" ends up at the "BACK" on one side and inhibits the coolant flow. Next, check the water pump, be certain it is spinning the correct direction regardless of whether you are using a V belt or serpentine type. Be sure timing is correct and that distributor is not off a tooth. Personally I dont think the lack of a
thermostat is responsible for your issues. Verify the head gasket position first.

Rick

trularin · #12 (**permalink**) 05-05-2005, 05:50 AM

Bolts or studs in the block for the head mounting?

Which ever one you put in, did you seal the threads?

As the engine expands with heat, the threads will allow coolant to escape into the rocker cover area.

Curt C made some good points. Since the system has not lost pressure sitting in the cool, I think I would reseal all of the head fastners. Use ARP thread seal, GM liquid teflon or Quick thread seal.

Reminder: If you do this, drain the cooling system first or antifreeze will come out the bolt hole(s).

Hope this helps.

S_Beaudry · #13 (**permalink**) 05-07-2005, 05:32 PM

Left system presurized for 3 days, it lost 2 or 3 pounds.

This is what I found after the 3 days.....

Any ideas?

Excaliber · #14 (**permalink**) 05-07-2005, 06:07 PM

Looks like it might be a leak related to expansion due to heat while running. That could be a head gasket or a crack in the head/block. Can you check for leak pressure drop while hot/running?

Water in the oil, not good.