*406 Runs Too Hot*

AGVI

AGVI

Well-known member
Joined
Mar 25, 2008
Messages
63
Location
Mississauga, Ontario
I think I should start with

1) Removing the under drive pulleys.
2) Remove the A/C condenser that is blocking air flow to the rad
3) Install the rad seals.
4) Install electric fans
5) Go with a mix of less coolant/more water and some water wetter additive.
6) I know a proper tune can help also.

It hits 190 for a few miles, and as long as I'm on the highway I'm alright, but regular street driving (stoplights, slow traffic) it gets to 210. It's never overheated, because I shut it down when I see it hit 210 otherwise the needle would keep climbing.

Anyone have any other suggestions? :D
 
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I've tried water wetter in my Z28, doesn't help much.... don't waste $9 on that stuff, here in FL you can get a 12pack Bud/Miller for $9 which is terrible beer but a better investment than this voodoo water wetter..

Electric fans and radiator seals are the ticket - I removed AC and trans cooler alltogether, now my 383 is running steady at 200F with the stock mech fan:D

What radiator do you have ? The $200 Summit/Northern aluminum radiator fits with a few minor mods and works great
 
well, if it's a aluminum radiator with decent size tubing you should be fine... increase the air flow thru the radiator with electric fans - 1993-2002 F-body fans and shroud is what I'd get.

Yes, the underdrive pulley is not really helping water pump efficiency.....
 
Make sure the seals are on the radiator, theu are critical for low speed. Make sure the fan clutch is good or just go to electrics, they really clean up the engine bay a Lot
 
I installed the DeWitt's alum rad and dual spal fans this spring.On the hiway the fans never come on and in town the temp has never gone over 200*. I have a 388 and push it pretty hard at times and no over heat problems yet.
 
Start with the radiator seals. Your fan can run all it wants - it needs good seals to pull the air thru the radiator, if the seals are bad or not in place it only moves hot air around.

What temp thermostat are you running ? if it's a 195 degree then it's normal to see 200F. Are you using the stock gauges ? When you see 210 it might only be 195 ?????

On the highway you seem to be getting sufficient airflow across the radiator so I'd definitely start with the seals to increase airflow at low speed or standstill.

At this time forget about a expensive radiator, the best radiator money can buy won't work if you don't have sufficient airflow.
 
Make sure your hood/cowl seal is in place. I see a lot of them removed or never installed. If the rear of your hood is not sealed, air will be pushed into the engine compartment, the radiator fan will now be trying to push that air out of the engine compartment instead of pulling air through the radiator.
 
MYBAD79 said:
At this time forget about a expensive radiator, the best radiator money can buy won't work if you don't have sufficient airflow.
Click to expand...

I'll start with the seals and a tune up. Will using a vacuum advance lower temps? I'm not using one. Also, will it help my headlights operate properly? They worked well with the 350HO and the vacuum advance hooked up to the distributor.

210 isn't really high, but it just keeps climbing if I don't shut it down. :skeptic:

:nuts:
 
Well..... the engine should run a lot better with vacuum advance... you have mechanical advance or nothing at all ? What kind of distributor do you have, what is your timing at idle/at 2500 ? Did you check with a timing light to see what's happening when you rev it to lets say 2500-3000 ??

With that cam the headlights will be a lil slow, that's normal.... how are your (vacuum assisted) brakes ??
 
Brakes are fine.

I'm not sure the difference between mechanical and vacuum advance. My distributor is an MSD not sure of the exact one. Also, have the ignition box.
 
Well... get it tuned by someone who knows something about non-stock V8 engines.... if you're running a distributor that is designed for a vacuum advance without the vacuum line hooked up you're asking for trouble. Do you have a vaccum can on that dizzy ?

Edit: just looked at a few of your photos at the other place. You have a vacuum can and on photo 0057 you can see what appears to be a vacuum line going to where the vacuum can is... looks like it's connected....
 
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What do you mean? Does your distributor have a vacuum servo or not? if it doesn't have it, it's a mechanical distributor. If you rae having cooling issues during cruising it might be smart to get a vacuum advance dizzy.
 
hey Les, this is one of you pics from the 'other place':

2148765938e390c.jpg

That small vacuum line in front of the passenger side valve cover is the trans line...ok... can't see the vacuum advance can at the dizzy, just a dark shadow....
 
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