Results of Your Your Cooling System Wisdom

[brent]

OK--cap-off test: engine hot, coolant's moving around, but not like it should:
DIAGNOSIS: thermostat, because if it opened normal I'd have normal circulation.
NOT the bottom hose. It doesn't collapse and spring appears fine.
NOT the hoses. No swelling on ends, no leaks.
NOT the sending unit simply because the truck overheats and runs like crap. Even if the sending unit was faulty it still overheats...
NOT the freeze plug.
NOT poor tuning. I'd be the last guy to peddle you some vain BS about "not my truck!" but the last tune-up was thorough, I took my time, and I feel good about it.
NOT the timing. It was garage-checked and declared fine.
NOT the outside AUX fan---it's a puller and blades going the right way. (Still a worthless piece of crap, though).
POSSIBLY (embarrasing)that under dash heater vacuum hose I knocked off last month and left it dangling drawing a very strong vacuum. Plugged the end of that and my temp didn't rise, but it's still not where I like it.
Going to try a 180 (from 195)that works this weekend, don't know what else to do. Heck, lowering it 15degrees can't hurt.
Thanks you all very much.
PS--you think breaking down and getting a nice flowkool or flowmaster water pump will make a diff? It would be strange if that was the last card to play, wouldn't it?

[Lippy]

Do not overlook the centrifugal fan clutch where the radiator fan is attached! Even though they appear to be "good" they are sometimes not. I had a very similar problem. Replaced the fan clutch and the temp guage does not come off the blue on the gauge. It is a cheap and easy fix.

[Ridgbak]

--I was over at Tads' school yesterday: we were looking over my cooling system and getting a few measurements for the installation of an electric fan. 'Rosco' has been running a little hot w/ the a/c on, and doing a 50-mile cross town trip w/ mega traffic lights, and 100+-degrees.
--Just like your diagnosis, brent, pretty much the same on 'Rosco'.
--Tad noticed that my fan was about an inch from being INSIDE the radiator cowling: instead, it's back a-ways from the cowling/shroud, allowing cooling air to escape between the fan and the cowling.
--Gonna get some 'extention bolts' to bring the fan forward, to be completely covered by the rad-cowling. Theory is: it might drop my temps down a few degrees.
--We're still gonna' put in the elect. fan, but with the history of my GWs, every little temp drop is a big deal.
--The fan is gonna' be problematic, in that I have two trannie coolers. The second one is in front of the radiator, along w/ the a/c. It's gonna be tight. We figure there's about 3 1/2" to work with in the fan width.

[Wesdog]

Brent, it's worth a couple dollar extra to get the higher quality brass Milodon or MrGasket Hi Flow thermostat, price is around $9. The MrGasket PNs: MRG-4363 160degF, MRG-4364 180degF & MRG-4365 for 195degF. Any speed shop should carry them and there are many online sources such as PAW, SummitRacing and JEGS. I get most of my online parts through Summit cause they get delivered to my location in 2 days.

On the waterpump, I have the Milodon model MIL-16271 aluminum hi volume pump as a spare for my custom WP from Evans. PAW lists it for $89.95 and it is a good quality piece from what I can tell. They say they use good bearings and there is no Weep hole to suck air into the system through. You might have to make some spacers for your brackets/accessories depending on your engine configuration. Some waterpumps have the spacers cast into the pumps as boss's and others don't. The Milodon pump doesn't to my knowledge, look at the photo I posted and compare it to your pump. Hope this helps.

[ June 21, 2003, 07:51 AM: Message edited by: Wesdog ]

[brent]

Your right, it's worth a couple dollars to keep that system cool. At the moment, in the summer, with the A/C on I have no security and I do not like that feeling. I don't like the potential engine damage that may be happening either.
I've printed out the rest of your great responses and now I have to come up with a custom plan to revamp my cooling system.
Again, thanks all.

[Wesdog]

Brent, I installed a TEE in the rear intake heater outlet and monitor the temp with a mecanical gauge at that location. That is typically the hotest area of the engine and I have had #8 piston damage a couple times in the past. I don't like OEM electrical gauges and am very paranoid about overheating my engine again. Just something to consider.

[joe]

Originally posted by Ridgbak:
[QB--Gonna get some 'extention bolts' to bring the fan forward, to be completely covered by the rad-cowling. Theory is: it might drop my temps down a few degrees.
[/QB]I don't know how correct this is but it's a pretty common and old theory that half the fan blades should covered by the shroud. Burying the fan completely under the shroud is worth a shot I guess. Let us know if it helps.

[Tad]

joe-, Ridgbak's meds are kicking in a bit this morning smile.gif
He needs a 1" to 1 1/4" spacer to sink the fan about 30% of the way into the shroud. Any more than this and the fan clutch will be too close to the radiator. Right now his fan sitting a good 1/2" out of the shroud.

[joe]

Yeah the shroud doesn't do much good with the fan behind it. smile.gif

[gsmikie]

also start it up and let it warm up then shut it down and reach in the shroud and with the palm of your hand feel the rad core sliding your hand across the entire width and height of the rad and see if you have hot and cold spots if so have the rad rodded out

[Joe Guilbeau]

Check this out...

Take the old thermostat out, and remove the center section of it, the part that opens and closes.

Drain your radiator fluid and flush and replace with pure tap water.

Replace opened up thermostat, now drive it till it heats up and let us know how hot it gets, ok?

This little test should tell you something, fan shroud, heavy duty fan clutch, 7 blade fixed fan, wesdogs suggestions about a high flow thermostat and a high flow pump are right on, now fill with distilled water and Preston's anti-rust lubicrant and you will be set for the summer.

Modine 581 radiators are the OEM replacement choice, with an industrial 4-core radiator based on the Modine 581 with louvered fins and two electric fans for help with AC and traffic in 113 degree heat should wrap it up.

Change to Anti-freeze in November thru March.

[Wesdog]

A sacrificial anode is a good idea if you run distilled water with Preston's anti-rust lubicrant or something else like WaterWetter.

And as Don S. has suggested in his writeup on cooling you might benefit from installing the late model Wagoneer front AIRDAM if you don't already have one. It creates a low pressure area under the engine and helps remove heat by increasing the hot air flow out of the engine area.

[ June 24, 2003, 08:23 AM: Message edited by: Wesdog ]

[Zacko]

Don't discount a worn out water pump. I've seen water pumps where the impeller was corroded away to the point that they just didn't move enough water. Not sure if 360's have a history of this but I've seen it on other V8's.
Also, a plugged hole in a head gasket could be the culprit. You mentioned that the water wasn't circulating well so I'd look more internal engine and radiator than fan.

[Jeep Jeep]

Wesdog, if you don't mind me asking, what did your rad cost, what part# and where did you get it?

[JAllenWAG]

Definitely spend the few extra bucks for a performance thermostat. I was having problems and all my system seemed fine. I replaced the cheapo 195 degree tstat with a high flow 180 from Mr. Gasket and now it runs about 20 degrees cooler. I didn't think it would make that big of a difference but it did.

[Wesdog]

Originally posted by Jeep Jeep:
Wesdog, if you don't mind me asking, what did your rad cost, what part# and where did you get it?Jeep Jeep, I had Evans Cooling build my radiator and I recently posted some info on my cooling system. http://www.ifsja.org/ubb/ultimatebb.php?ubb=get_topic;f=2;t=020095

I found my Evans Cooling file and the receipts for my radiator. Here are the costs for the custom Griffin Aluminum Radiator and SPAL Dual Cooling Fan Setup:

Radiator 155242-x: 27.5"x19", 2 rows 1.25", Chevy Outlets, Universal Racing Radiator = $367.50

SPAL Dual 11" Puller Fan PF-13 = $260

Additional Labor charges = $290 Labor Breakdown: Radiator Conversion=$150, Fan Mount=$100, Material and Hardware=$40

Shipping of Radiator and Fan assembly= $60

The labor charges were to modify the Griffin universal racing radiator for my application and add the mounting bosses for the cooling fans. I have the drawings that were made for this project. As you can see it wasn't cheap but I am very pleased with how it performs. Let me know if you have any further questions. Wes
http://www.fullsizejeeps.com/jeeps/files/Misc-Pictures/401_Griffin_Radiator1.jpg

[ June 24, 2003, 08:58 PM: Message edited by: Wesdog ]

[Jeep Jeep]

Thanks Wesdog for the info. I wonder how it would be with the stock fan and shroud?

[Wesdog]

Originally posted by Jeep Jeep:
Thanks Wesdog for the info. I wonder how it would be with the stock fan and shroud?It would work with the original fan and shroud. I did have to modify the hoses because of the location of the side tanks and nipples. The fan shroud would need to notched. Also, any good radiator or AC shop should be able to do this work I think.

[ June 25, 2003, 06:54 AM: Message edited by: Wesdog ]