I've checked the fan 2X and it pulls, as it should. It's a new surge tankk, form Southern, so it should be OK, but would a bad sealing cap give these symptoms? The spewing cold coolant has to mean that the radiator isn't seeing the coolant, i would think.

Thomas, where would I find a water pressure gauge to put in the intake?

I spoke with Southern, and the engine was run off and on for 2 hours, wiht this WP, so those things seem unlikely, and they don't use the one way head gaskets.

thanx again. steve

Problem
 

Keep changing or check one item at a time.
Water Pump(turning)
Cap(too light or leaking air)
Lines(crimped)
thermostat(shut or upside down)
What is different now than what was on the dyno?
It sounds like you should be able to nail the problem

I've thought of those issues. What's different from the Sourthern run in the shop?

1) T-stat (and the "sensor sees" the intake fluid, the "tit" points to the surge tank.
2) Surge tank (and when I got it, it had a piece of welding slag in it.)
3) Repro 14# cap
4) hoses and coolant
5) New radiator (seems very unlikely)

these are some of the same items that seem to be suspect here, but WP was tried as well at Southern.

thanx s

Are you sure that tit is turned the right way, seriously!%/ I know theres only two ways to do it but things happen. BTW, living here in Atlanta it gets hot & muggy like Houston and my SO has never gotton over 90 c in stop & go traffic. Once you find the problem you'll have no worries.

Steve S. - SA doesn't have a dyno (yet) but rather an engine run stand.

there must be a hundered of us with these 427s and a surge tank, so if I've got the t-stat in wrong, let me know. With my surge tank from Southern, it really can only fit one way, and that is with the sensor, that part that looks like a little brass plug, into the intake, and the "tit" or point that is this culmination of the 3 brass strips, or arms pointing into the surge tank. steve

I had such a cooling problem it wasn't funny...I actually overheated at the beginning of DVSFII !! To test your flow, I'd remove the thermostat (temporary)...it's there to give you a "Minimum" temperature in the block...not a max. If your problem goest away, you've got a bad tstat.

Also you said you are running a 60/40 mix. Try pure water with Redline Water Wetter additve. This will drop your operating temperature right off the bat.

It seems to me that you can see water churning in the expansion tank with the thermostat open and the engine revved to 2500 rpm. If you want an even more obvious check, remove the thermostat completely. You should have flow at all times.

It sounds like you either have a large amount of air in the system or a defective water pump. The other less likely candidate is a slipped damper making the timing mark inaccurate.

By the way, what's your idle vacuum running?

Strictly personal, when you ask about the idle vacuum, I assume that you mean the intake manifold vacuum at idle. Yes? I haven't measured that, but should be 18 mm Hg, I think, but I can check. Your idea of a slipping damper or some odd ball deal with the timing (where it would like right on the gun, but be wrong for another reason) is scary, but as you said, very unusual. thanx steve

Steve,

You can get one at any auto parts store. The trick is to ask for an oil pressure gage. A cheap mechanical gage will work just fine.

Good luck.

Believe it or not you could have a big fat air bubble in that block. Try pressure flushing it (as simple as removing the hose(s) and pushing water through the system) effective but messy. Or if you can have the system vacuumed down.

It may take several attemps to completely remove the air.

Good Luck,

Air
 

One of the best ways I found to fill the cooling system was with the nose raised as high as you can get it on jack stands. Never had a air pocket.

OK, I got out there tonite and raised the front end of the car, and tried to re-bleed the system via the temp gauge in the intake...maybe a few bubbles, max. Bought a 16# "Murray" cap for $2.99 (O'Reilly no longer carries Stant) and viola, tho' the temp rose to 95C it didn't spew coolant anywhere! Unfortunately, my IR gun picked this evening to die (you picked a fine to leave me Lucille) so I couldn't check temps anywhere, but it does look promising. Also, it is raining here in Houston, so I didn't get a chance to drive it and test that. I'll post the list when I have more info. thank you to everyone who has helped me...but, it ain't over 'till it's over. steve

I'm not sure I understand the logic of going to high pressure radiator caps.

A 13lb cap will raise the boiling point of water to about 250 Deg F. So more pressure will raise the boiling point higher, but IF you get to 250 gimme a break! Something is way wrong all ready!

Less pressure means less wear and tear on hoses, surge tanks, radiators etc. 13 is about as high as I will go with MY systems.

Ex
 

Come on out of the "Stone Age"
Click here
http://www.crracing.com/temp/

:D

No thanks, I like it in my stone cave. 13lbs for 250 Deg or 30lbs for 270 Deg? I'll take door number 1, not sure my "stone age" copper radiator and old FE surge tank are ready for 30lbs. And long before my temp gauge reads 250 I'll all ready be freakin' out and taking action of some kind!

.....maybe if I was racing,,,,,,but then again, I'm not!

Ex
 

I was only talking for those who are using new racing quality cooling components. I agree with you for your application. That stuff wont take the extra pressure without problem.
Say goodnight to Wilma for me.:LOL:

Steve M,
Call it a little late in the game but I didn't see it mentioned earlier, you don't have a reverse rotation water pump on there do you? Did SA spin it one way and maybe your spinning it the other way?
Just a thought.

I was running a 14# repro cap, but the FLAPS I went to didn't have a 14#, and I was concerned about going to the next lower one (13#), so I picked the next one up in line. Ultimately, I'd like to find a repro 14# cap that works. I don't think it was the increase in pressure, but rather a cap that sealed. It was Tom Kirkham who mentioned that many repro caps don't seal well. thanx and I'll keep the list posted when I 've got more info. BTW, the engine was installed just as it came from Southern, so no chance I reversed their WP. steve

Spent a bunch of time speaking with Bill Parham at Southern, and with Louis there as well. Obviously, Southern knows their engines and with my meager knowledge, I came away learning a bunch. I have spoken with Bill and Louis several times over the 18 months; from ordering the SO, to getting it up and running, and have always found them to be very willing to help in any way possible and to be concerned and interested in every aspect of the process. Anyhow, the take home messages for me were.

1) These engines produce a lot of heat and therefore it is imperative that the cooling process begin reasonably soon, and not when the engine water temp is already in the 180° range. Therefore, in warm climes, like Houston, they install a water restrictor in the surge tank neck, and only recommend a 160 t-stat if you live in the colder parts of the country. That wasn't my problem, but that change would probably help me a little as well.

2) Bill recommended a manual override on the Spal puller fan, instead of letting it come on via the thermostat at 180 or 190°, again, if the water is already at 180° before any coolng begins, it is harder to get it to maintain a reasonable temp.

3) He likes at least a 19-20# cap, and when he was involved in racing these 427s, they ran 26#.

4) His acid test for good airflow is: With the car warmed up to operating temperature, ambient temp around 75° and cruising at 2500-3000 RPMS, the water temp should be 80-92°C.

Steve...Southern's on the money in my book. Always harder to cool them down after they get hot.

I run a switch for the two pushers and the puller, and they get switched on once the car gets to about 75-80C on first warmup. They stay on unless I get on the freeway. I run a 160F thermostat and just a 13# cap.

In extremely hot (100-110F) Fresno summer days in stop and go traffic, the motor never gets above 85-90C.

I had a 92 Vette that I used to drive into XXXtreme heat (120F not unheard of...ask flipper) in Imperial Valley for work years ago. I put in a switch for the fans on that beast as well and never had a problem, though many Vette and F Body cars couldn't take it with their t-state controlled switches and bottom-sucking air flows. Learned this from the CHP which used Z-28s down there.

Glad you found the cause (the cap not sealing).

I also run very little coolant. Mostly Water Wetter and water. Learned that from autocrossing, where you run flat out for 1-2 minutes and then sit idling in the hot sun for 10 minutes waiting for your next run. Water is still the best cooling fluid...WW and a little coolant just add some essential lubricants.