So, help me debug this..

newly rebuilt 460 and C6 tranny. (will run hotter for a while I'm told)

custom built steel radiator, 6 core, with tranny cooler. total fin area is same size as radiator U mount inside shape. (radiator mounts INSIDE the Radiator U due to clearance issues, holds about 2 gallons of fluid, currently new 50/50 premix)
have both 7 and 13lb new rad caps.

dual fan aluminum shroud, with 2 - 12in electric fans, 1700cfm each, fans powered off relay with direct power from the battery., 12 gauge wire for both leads (located on inner fender right at the right front air deflector, you can see the setup in the attached pic) (fans in puller configuration)
battery ground direct to engine, then engine to chassis.

new water pump, aluminum with brass impeller, stock size pulleys for engine and waterpump (no underdrive).

160 degree thermostat (tried 180 before that).

160amp alternator.

New intake manifold, heads and block were hot tanked clean during rebuild.

lower rad hose is stainless exhaust pipe with rubber hose ends to rad & water pump (no collapse on acceleration). Upper rad hose WAS stainless exhaust pipe, now a section of coolflex with shiny hose ends).

on a 460 the rad output/water pump intake size is 2in, while the thermostat output/rad intake is 1.5in.

the fans are controlled by a control box that takes the temp sensor (supplied with the gauges), and allows adjustment.. Currently adjusted to On at roughly 180, Off at 160ish.

it idles great, holds 180 all day.. drive it and the temp climbs towards 240ish (3-4 miles). once there, doesn't seem to be able to cool its way back down.

I have not tried diverting the tranny to a separate cooler.

the A/C condensor is 100% of the rad U space as well. mounted within 1/2 in of the rad face. see second attachment.

A/C currently not working due to leak under the dash, to be fixed in early October.
(condenser not supplying additional heat).

So.. what else should I look at? other questions you might have.

oh, the outside temp during today's episode was 106. last week in Detroit the temp was only 92, but it was stop & go traffic (worst possible conditions)..

all this leads me towards tranny cooler contributing heat. ah, tranny running higher stall converter (TCI 442100, 2400-2600rpm).

the trans cooler is in the lower tank, which means it would contribute heat immediately without any cooling applied before the fluid was sucked into the engine.

Sam

 

The fans are pulling and not pushing, right?

 

correct.. puller config, and the air DOES get quite hot.. so they ARE pulling air thru the rad.

oh, the air deflector rubber gasket at the top of the rad (hanging from the hood), is not currently in place. I assume this is the skip around air stop. air like liquid will take the path of least resistance.
you can see the strip where this gasket attaches in the first picture above, right side, just above the hood latch.. goes between each side of the hood support mechanism.

Sam

 

Wow, that is puzzling. Prolly grasping at straws, but that maybe what's req. here- try pulling the t-stat out and dropping in pot of heating water w/ thermometer in it to see if it's opening at 165??

 

did that already with both the 180 and the new 160... both open within 5 degrees of rating. stock 460 uses 180degree

Sam

 

That's an interesting problem you've got there Sam. Your shrouding looks great. If you hold a piece of paper to the front of the condenser with the fans running, does it get sucked in with gusto?

 

haven't tried that, but I can feel the air on my hand..

but notice that the temp rises when MOVING, such that the fan flow shouldn't matter.. in fact I've been experimenting with ways to turn the fans OFF when moving, cause it just wastes electrical cycles.

sam

 

Try removing your radiator and back flushing it and see if any rubbish comes out .
It seems as though everything is new or reconditioned , but you can still get a lot of rubbish come out of a reconditioned engine even after it has been hot tanked .
A partially blocked radiator will give the issues you have ..

Worth a try..

 

Are you sure you have the thermostats in correctly - ie the little pointy chinese hat part is in the housing pointing toward the radiator - not the engine, and you've retopped off the coolant since the thermostat has opened, right?.

I had just the opposite problem. I could drive at 160 all day but as soon as the truck stopped moving, it would gradually climb up and overheat. My set up is quite a bt different - traditional fan. Installing a fan shroud helped a lot but ultimately, 1500 miles later it stopped with the break in.

This sounds weird.

It has been suggested that a hotter thermostat will restrict flow and keep the coolant in the radiator longer to cool it more. I don't buy it because the engine produces a certain amount of heat and the longer the coolant is in the radiator the longer the other half is in the engine getting hotter. It's a curve though, in other words does your fan system elliminate heat faster than the engine produces it. If so it needs more time in the radiator. Some folks swear by this. I don't. At 240 degreees all the thermostats are wide open and flowing. But if it never gets that hot, the restriction might be what you need. As a last resort, you might try a 220 degree thermostat.

 

yeh, we picked the lower stat to get the water out of the engine sooner so that the fans could do their thing sooner.

the stat will really only go in one way, but I've been doing this so long I can't imagine putting it in upside down.. (temp blob IN the manifold).. vents lift to allow seepage bypass..

I'm starting to lean strongly to the tranny cooler ADDing heat.. but don't have a way to measure the trans temp.. will call TCI Trans tomorrow.. altho they DO say temps will go up with higher stall converters.. where to put another powered cooler will be a fun challenge..

sam

sam

 

How much room do you have in front of the radiator at frame height. I have a BIG transmission oil cooler I hung in front of the desert cooler radiator. But I also wanted to install an engine oil cooler. I put it flat in front of the radiator with a very small airfoil below to turn some air up into it.

But honestly, I don't think the trnasmission cooler is causing your problem. It may be adding to it with the new rebuild and all.

And hey, try the hotter thermostat. For <$10 it might be worth it just to see. Then if it doesn't work, we can tell the guys who swear by this it doesn't always work.

Also, both fans are working at high temps right?

Here's a pick of my 51 set-up. Transmission cooler in upper left of radiator and oil cooler in front laying flat next to the remote filter:

 

I have no more room in the rad air flow path. I am thinking of places to hang a separate cooler (with fan).. I think down near the running board..

good thing I just added a 6 circuit direct feed fuse panel for these add ons!..

TCI FAQ does say that the higher stall converters do run hotter than stock (such that you could burn out the tranny if you hold them too long at some part of full throttle too long)..

and my heat problem is ONLY while moving..

yes, both fans are either on or off.. never just one fan (12amps *2)

Sam

 

Thought for others to comment on.
1. With closed side panels and no vents in the hood, is there good air flow exiting the engine bay.
2. If you block open the hood 6-12 inches for testing does it do the same when driving?
3. With the shroud not funneling (it's flat) all the air to the fans, is the air not in front of the fans disturbing the total air flow through the fans. I think there should be holes in the shroud everywhere their is not a fan to let the remaining air flow thru. My driving car has the fans mounted on rods, so as to not restrict the air not going thru the fans. The fans are pulling mostly the air in front of the fans, the rest is daming up in
the shroud.
chuck

 

Randy Jack had a similar problem. He fixed it by getting rid of the shroud.

see his comments on page one of this thread.

https://www.ford-trucks.com/forums/3...pped-back.html

 

3, many of the production cars have flaps on the shroud that get pushed open by drive time airflow, and held closed by idle time (fan only) air flow.

1. I think there is sufficient room for air to flow out with the hood closed..

2. hm.. hood partial at 30mph. eek

sam