nailhead overheating...HELP! ive reached wits end!

I have a 58 364 that I've put in my 30 sedan rod.Its got a rebuilt
waterpump,new 180 thermostat. I've got a 4 row 66 Mustang radiator
thats new. The fan is no more than an inch from the radiator. Its got a
new temp guage and sender.After running for a few minutes , the temp
started increasing like normal but after about 15 minutes the temp
continued past 210 so I shut it down. I took the thermostat out and at
the same time noticed alot of rusty coolant so I flushed alot of water
through it.Tried it with no thermostat, same result.Put the thermostat
back in with the guts removed for a little restriction,same result. I
even put an electric fan in front of the radiator to make sure I was
getting enough cooling,same overheating.When I got the engine it had
been rebuilt with about 2000 miles on it. It sat for about a year and
I'm wondering if there might be enough rust to make hot spots and if
so, is there a way to flush it out? Am I missing something? Any help
would be great. Thanks

 

anyone?

 

210 at near sea level should boil over bigtime after shutdown with water w/o antifreeze.

if it did not, then borrow one of those turkey thremometers and test the temps in the radiator. Might be just the gauge.

 

Do a "Block Check" to make sure you don't have a combustion gas leak into the cooling system. Can't get any radiator flush nowdays worth a shit. White vinigar is said to work but never tried it.

 

even with an 18 pound radiator cap? I had a 13 pounder on there originally, but was losing alot of water even after shutting it down at a fairly low temp.

 

how do I do a block check? take it to someone? if so, how do I know who to take it to?

 

Do you have a shroud or is it just an 'open' fan? A shroud will make a HUGE difference.

 

no shroud. but im running no hood and no fenders. the thought of building a shroud for it makes me wanna barf looks-wise.

 

I've heard of using a CO smog sniffer in the radiator opening to test for exhaust in the system...but I would think you should see bubbles on a top tank type radiator.


losing water with 13 lb cap at lower temp shutdown does not sound good at all, but keep checking here for ideas. I don't know if that motor type can trap air when refilling??

 

Block check is done with a device that looks kinda like a basting squeezer for cooking. What is done is the mechanic puts some blue fluid in the device up to the line. Then with the engine running and the coolant drained to just below the top of the radiator core, the block checker is then inserted into the radiator neck and squeezed several times to see if the blue fluid turns green or yellow. The more exhaust gas the more yellow. If it stays blue then your not getting exhaust gases into the cooling system. A good radiator shop should be able to do this.

 

What kind of distributor are you running?

 

Even know I have one, I don't know dick about the water gallery's on a Nailhead. Sounds like either a head gasket is blowing by or there is an air lock in the motor. Try to run it from cold to operating temp without the cap on the radiator, if it starts to puke water up and out like a fountain thats air in the block. You just then need to find out how it got there.

Doc.

 

Along the lines of "distributor" check your timing. Can cause lots of issues even when the engine sound ok. My 61' 401 ran about 190-200 degree (temp)on the highway all the time. The timing on my motor was listed in the books and the owners manual at 12degree before TDC. Check out what that year motor was supposed to run.

 

Damnit, Ash is right, I always forget to consider timing issues. It could well be that but I would try the run it without a cap thing still.

 

I have been running my .090 over bored 330 DeSoto for about 2 1/2 years now with NO SHROUD with out a cooling problem..

Never been over 195, No T-Stats, Straight Water. ou don't need a shroud on a Hot Rod if your Cooling system is Up to Par.

Sounds like the problem your having is a simple one, Either your getting Exhaust in the Cooling system OR Your Mustang Radiator is just to small.

I know they are spendy, But more guys need to spen the $$$ to have a GOOD radiator Built to fit there application.... Or live with Heating problems.

 

I'm leaning toward the rust sediment idea. Especially since you got rusty water out of it already. May have a couple inches of crap inside the block at the bottom.

 

Timing? Number one on the most important scale. Water pump A/C or non? The A/C pumps sometimes move the water to fast to be cooled. Radiator? If you had a bunch of rust come out you may need to havet he radiator cleaned out. And a shroud doesn't have to be ugly. Take a look at a couple of the tech threads on them.

 

There are block drains on the Nailheads. I've pulled them and flushed the block real good before. Center of the block above the oil pan, below the freeze plugs.

 

"It sat for a year". Any chance that a mouse built a nest in the cooling passages? Rad cap missing or rad hose gone will let the little beasties in there, pure hell to get the crap out. I've had engines crammed right full of grain and stuff through a heater hose opening.

 

Reread your first post, it sounds like you aren't driving it, just running it sitting still. Is it in the shop or outside? Is the hot air circling around and back through the rad? 210 isn't too hot under these conditions. Try taking it out on the road, or at least outside. To see if it is a too-small rad, run a garden hose over the rad while it's running. If it is a gasket or whatever, it will still blow water out the rad, even with the extra cooling.

 

I missed the sat for a year bit. Did you flush the motor before putting it together? If not drop off both rad hoses and run pressurised water thought the system.
If you do a search for overheating issues I detailed how to make your own pressure flusher. Water at tap pressure alone is not enough and a pressure washer cant deliver the volume of water you need.
Doc.

 

Its a stock distributor with Pertronics electronics inside

 

On this motor , the book calls for 5 degrees of timing so thats where I put it.

 

Had the same problem on this car. Also, the faster I drove it the hotter it got. Had the distributor recurved. It was way off but the real problem my dad found out was that the water was moving too fast and couldnt cool down in the radiator. He put a big nut in the lower radiator hose and put a hose clamp on it. Fixed it.

 

It doesn't have any bubbles coming up in radiator. I also put an electric pusher fan on front of the radiator . It seemed to slow the rise down a little but it still went up.I've also driven it around the neighborhood with the same results.

 

http://www.arrowheadradiator.com/14...apability_in_high-performance_automobiles.htm

 

The water pump is a non A/C

 

You have vacuum advance, did you disconnect the vacuum line at the distributor and plug it before you shot the timing?
If not, you should.

Once you have the initial timing set up, re-connect the vacuum line to manifold vacuum and not to ported vacuum.


Generally manifold vacuum is obtained from below the throttle blades and ported vacuum is obtained from above the throttle blades.

Manifold vacuum shows about 17"-19" at idle on a stock engine and also with a very mildly cammed engine.
A hot cam of 270*-280* advertised duration has about 10"12" of vacuum

Ported vacuum shows zero vacuum at idle.


Since the idle mixture is lean it takes more time to burn.

Therefore, you need the vacuum advance sourced to manifold vacuum so you'll get additional advance at idle.


If you don't have a vacuum advance or it's not working the engine usually overheats at idle or in heavy traffic.
Worse in the summer.

The overheating you describe is what generally happens when a vacuum advance isn't connected, connected to the wrong source or has failed.


An operating vacuum advance can be verified by:

Additional timing over initial is shown at idle.
My late BB Buick (462") shows 32* total advance at idle with an initial timing of 12* BTDC.

If no timing light available, just listen - or read the tach if you have one - for idle speed to increase a small, but noticeable amount when vacuum advance is connected to the preferred source which is manifold vacuum.



Mechanical advance is controlled by RPM.
Vacuum advance is controlled by vacuum which reflects engine load.

These two advance systems overlap as required so as to give you the correct amount of advance for the situation.

Don't be surprised to see 45*-50* of total advance if you spin the RPMs up to 1500-2000 or so with no load on the engine.
It doesn't hurt anything.



Overheating on more than a few hot rods has been cured by connecting the vacuum advance line to manifold vacuum.

 

The MSD distributors specifically call for ported vacuum.

According to the factory manual. The spring loaded side of the diaphram is connected by a pipe to an opening in the carberator barrel. This opening is on the atmospheric side of the throttle valve when the throttle is in idling position so that there will be no vacuum to operate the advancing mechanism.

So the factory disagrees as well.

 

Is the water pump moving he coolant. Look in the radiator wih it running. Water should be moving across the radiator. The props can seperate from the drive and nit pupm water