Click Here!

Go Back   IH PARTS AMERICA > Tech Forums > Engine Cooling & Mobile HVAC Tech
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read Photo Gallery IH Store Home

Thread Tools Display Modes
Old 01-06-2013, 01:30 PM   #1
Junior Member
Join Date: Jan 2013
Member Number: 5366
Location: Conifer Colorado
Posts: 2
Default Scout with 392IC running hot!!!!!

I purchased one of the down flow radiators from (rnd fabrication International Scout II heavy duty downflow radiators) for my IH Scout with a 392 to "fix" my cooling issues. I also purchased the dual electric fan option and fan control relay and am running a 16lb cap. After installation the engine continued to overheat. (in the past I run either a stock 3 or 4 row radiators with the stock Scout clutch fan with shroud, neither of which cooled the 392). I have tired 3 different thermostats (160, 180 and 195). I flushed the entire cooling system twice. I added a 16" pusher fan to the front which seems to help but was not a fix. My last move was to get rid of the 2 electric fans (as the control/relay went bad) and replace it with an 18" mechanical fan with a custom made fiberglass shroud. At which time I installed a new water pump (the old one looked good when removed). Last ditch effort was to add some royal purple ice cooling additive. None of this is really fixing the cooling problem as it will reach 200 just idling and hit over 230 when driving.

More about the Scout - it runs on 36" tires and 4.88 gears. It has a tf727 transmission and a Dana 300 transfer case with stock gears. The engine is a 1972 392 improved cooling motor running a isky cam (isky-190125-26) with bbc valve springs, custom TBI efi fuel system with computer controlled distributor, rpt aluminum intake manifold, and stan's headers (tri-y). I would estimate no more than 300 hp since the stock 392 runs about 8:1 compression. The engine runs fine with good compression on all cylinders even though it has never been rebuilt.

Any suggestions on what the cooling issue could be?
superfi100 is offline   Reply With Quote
Old 01-06-2013, 02:38 PM   #2
Scoutboy74's Avatar
Join Date: Apr 2008
Member Number: 453
Location: Daze Crick, Jefferson
Posts: 4,145
Default Re: Scout with 392IC running hot!!!!!

Do you have an infrared thermometer? If not, you should get one and use it to take readings at various points in the coolant passage ways. Perhaps you will discover a blockage, or you May discover that whatever gauge you are using is reading high. 230f, if actual temp is extremely hot for one of these engines to run. I have a 392 ic in my sii and have made no special provisions for cooling. I have the stock radiator with stock shroud and a clutch fan backed by an airtex 8-hole-hub water pump. The engine will heat up some when I'm working it hard on the trail as is to be expected, but it will idle all day long with coolant temp hovering around the thermo set point even in summertime.
Coal Trickle - '99 Dodge Ram SLT 2500 Q-Cab SWB 4x4 - 5.9L 24V CTD/NV4500/8800# GVW/12K# winch
Hooty - '74 SII 4x4 - 392/TF727/D20/3.73 D44's/Spartan FA/Krac-lok RA/33g Fuel
Lemuel - '73 1210 Reg Cab 4x4 CS - 304/TF727/NP205/4.09 FA25 & 4.10 RA16/6800# GVW - "Pull Lemuel, pull!"
Organ Donor - '72 1210 Reg Cab 2WD - 392/TF727/4.10 RA17/7500# GVW - "Use my body to keep you alive!"
Mongo - '71 1210 Reg Cab 2WD - 345/TF727/4.10 RA17/6100# GVW - "Mongo love candy! Duh, huh, huh!"
Scoutboy74 is offline   Reply With Quote
Old 01-06-2013, 07:06 PM   #3
Greg R
Senior Member
Join Date: Jul 2008
Member Number: 527
Location: Lebanon, OR
Posts: 792
Default Re: Scout with 392IC running hot!!!!!

If it's overheating when idling, there's 3 things I can think of:
1. Airflow a. Fan and fan spacing; b. Correct fan; c. Radiator thickness and fin count causing a flow restriction.

2. Water flow. A. If it's a new pump, are the clearances correct; b. Any obstructions such as collapsing hose or crud; c. Is there enough water/coolant to fully wet the radiator internally

3. Timing and fuel mix.

The Scout 2 was to have a cross flow radiator, which for the frontal area it was limited to was the most efficient. If the new radiator went thicker to give more tube area, now there's more air restriction, and the same goes for higher fin counts. They don't come broke from the factory, something ain't letting the heat out, the mission is to find the weak link, not new parts.

Craig, a long time member here ran across this some years back and had an excellent thread of the detective work he did. I can't find that one, but he did post this which is also good:http://forums.IHPartsAmerica.com/eng...erheating.html
Greg R is offline   Reply With Quote
Old 01-06-2013, 09:28 PM   #4
Senior Member
Scouty's Avatar
Join Date: Jan 2007
Member Number: 8
Location: Sacramento, CA
Posts: 516
Default Re: Scout with 392IC running hot!!!!!

I'm running nearly the identical setup, 392ic, 36" tires, 4:88s, 727, and Dana 300. My 392 is stock, stock intake, edelbrock 4bbl, stock manifolds and dual exhaust. Recently replaced all bearings, motor had 70,000 miles on it, tore it down and everything looked good. Put in a new water pump and bent the fines as much as possible without hitting the housing. I'm running a stock Scout II radiator that was rotted out at the local radiator shop. Have a Mark viii electric fan with a switch that comes on at 180. Also running a 180 t-stat. At idle or normal driving, temp stays between 180 and 185. At highway speeds 60mph the temp runs at 190/195. I don't think the stock radiator cooling capacity is enough, so I'm planning on picking up one of Jeff's (IH Parts America) direct replacement aluminum radiators.

I took a look at the radiator you have, and based on what they said on their site about not being able to run a fan clutch or a spacer I'm thinking the radiator might be too thick (same as what the previous poster said). Also not sure what efi you are running, but if it's running lean that will cause the motor to run hot, lastly advance timing can also cause things to run warm. My bet is its a combination of thick radiator and lean condition. Good luck.

73 Scout II
74 Scout II
Scouty is offline   Reply With Quote
Old 01-14-2013, 05:05 PM   #5
Junior Member
Join Date: Jan 2013
Member Number: 5366
Location: Conifer Colorado
Posts: 2
Default Re: Scout with 392IC running hot!!!!!

Thanks for everyone's input. My pc power supply went out and just got back online.

I do have an ir temp gauge and all readings look the same with abut a 10 difference from back to front on the intake and thermostat housing. I have not yet checked the freeze plugs in the block to see what they are reading so thanks for the tip.

My efi system is a GM parts setup with a custom chip from bill (usn-1) hamilton hamilton fuel injection So I am pretty sure the air fuel mixture is correct. Plus the plugs do not look like the engine is running lean. I have a fuel pressure gauge mounted in the hi-pressure line and it always reads 18 psi so there is no drop in pressure that would cause a lean condition.

The in-dash mechanical temp gauge sending unit is mounted in the rear drivers side coolant passage on the intake. I have the electric fan control sending unit mounted in the thermostat housing and the fans, when set to turn on at 180, turned on when the temp gauge read 182.

I did look a the 10 tips on cooling and the only 2 that are not verified are purge hole in the thermostat housing and the water pump vain clearance. I will be checking those this coming weekend.

Since the engine has never run cool, including when I was running an stock radiators (3 and 4 row) and now with the one from rnd I'm not sure that the radiator is the issue. Especially since several of you are running 392's with stock radiators.

I should also add that I live at 8,500 ft and often wheel at elevations of over 10,000 ft. I am not sure how much the high elevations thin air affects cooling systems. Also when testing in the driveway, spraying the radiator from a water hose cools the engine rather quickly - not sure if that helps.
superfi100 is offline   Reply With Quote
Old 01-14-2013, 05:23 PM   #6
Senior Member
FDChappie's Avatar
Join Date: Aug 2011
Member Number: 3742
Location: Northern New California
Posts: 1,586
Default Re: Scout with 392IC running hot!!!!!

Sounds like your electric fans are not pulling enough air through the radiator.
FDChappie is offline   Reply With Quote

392, cooling, hot, radiator

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

All times are GMT -8. The time now is 10:58 PM.