Overheating: Radiator or head gasket?

tweakedlogic · 07-14-2010, 06:33 PM

So my truck over heats. I have a stock motor and radiator, w/ 17" electric fan.
the first time it happened is after I fixed the A/C. I noticed in stop and go traffic the temp would rise. I never let the needle get above the A in Normal. I would shut off the a/c.
I then installed the current 17" fan replacing the 15" fan.
It was better for a few weeks. But I did some suspension mods and it has sat for two weeks until today. I was running around town and noticed the temp was already at A. so I shut off the a/c and it started to cool down. I parked for a while and left the e-fan on. got back in and it was @ O. Cool. I left the a/c off, but got stuck behind some traffic for several minutes. I saw the needle start to climb again. the a/c was off.

It doesn't use any water and I've never seen any leaking. So, is it a clogged radiator, or a bad head gasket?
Gaskets are cheap, but a pain to install. radiators are easy to install, but expensive.
I don't know what to do.

Ahteixeira4x4 · 07-14-2010, 06:42 PM

If you have water in your oil than it is your head gasket.

*jd4242* · 07-15-2010, 12:50 PM

what fan are you using?the ex needs about/over 3000cfm to stay cool

**Maniak** · 07-15-2010, 01:02 PM

What your describing is not enough airflow. If its fine at say 50mph cruising then its more likely the fan. If at 50mph it overheats then your looking at the radiator..

For head gasket you would have oil in the water, water in the oil and or smoke out the tailpipe.

Since your running an electric fan, you really need to make sure its pulling enough cfm. There have been mixed results using the blackmagic fan which pulls "around" 3000 cfm on the 1st gen explorers. It seems to be partly related to how the vehicles are driven and in what climate.

~Mark

tweakedlogic · 07-15-2010, 06:18 PM

I don't remember the CFM rating. It's the same fan I use in the Rx7. If it's enough for the heat generating rotary @ 8000 RPM on the track, it will be enough for any stump pusher.
I don't have any oil in the water, or water in the oil, and no steam from the tail pipe. I guess it must be the radiator. Darn! I didn't want to replace it until I could afford the 2 core triple pass. @ $600, I will have to wait for that and buy a OE. Thanks guys.

*rhauf* · 07-15-2010, 07:21 PM

get rid of that elec fan and put in a stock clutch fan and shroud.. it'll work way, way, way better.

i'd also replace the radiator. i'm just running the best one i could get from autozone and it works great (even towing, even in 100 degrees) of course i'm running the stock fan too.. which whurrs like crazy when its hot.

it is possible that it could be a cracked head/blown head gasket just not involving the oil... but id put my money on cooling first.

**Maniak** · 07-15-2010, 07:46 PM

Quote:

Originally Posted by tweakedlogic

I don't remember the CFM rating. It's the same fan I use in the Rx7. If it's enough for the heat generating rotary @ 8000 RPM on the track, it will be enough for any stump pusher.
I don't have any oil in the water, or water in the oil, and no steam from the tail pipe. I guess it must be the radiator. Darn! I didn't want to replace it until I could afford the 2 core triple pass. @ $600, I will have to wait for that and buy a OE. Thanks guys.

8000 rpms on the track means your moving.. If your moving 50mph or so then the fan isn't helping anything since you moving 50mph is going to push more air than that fan can..

Now, if you said it could keep it cool a 8000 rpms while in neutral, that would be different.. When your not moving or your moving slowly is when the fan is doing its job...

~Mark

*92exp4x4* · 07-15-2010, 08:26 PM

Maniak is right, if you are moving at all, then the fan's need to exist goes down. Also the shroud makes a big difference to how much air is pulled through the core of the rad. With no shroud the air can be drawn from between the fan and the rad because it is easier to move it from there. Think the path of least resistence. Also there were two radiators available. A single row core and a 2 row. I have converted all mine over to the 2 row for more capacity. If yours is a two row then the core will be about 2 inches thick.

tweakedlogic · 07-16-2010, 01:17 AM

I don't think you guys understand the rotary. it makes hellasious heat. the one thing that kills them. then boost them and run them on the lean side with advanced ignition curves and you have a kiln.
it is not the fan. I know this fan pulls more air than the stocker.
I was worried it may be the head gasket because a fiend of mine suggested it may be and wanted me to come over to his shop and test the head with a pressure gauge on the radiator. I would do it if he wouldn't make me do all the work while he made un-funny jokes and got in the way.

I will just ahve to for go some planed mods for a while linger so i can buy a radiator. It's just really bad timing. boss closed shop so I lost my job this week and after some suspension mods I really need an alignment.

I do appreciate your help.

*rhauf* · 07-16-2010, 01:27 AM

Quote:

Originally Posted by tweakedlogic

I don't think you guys understand the rotary. it makes hellasious heat. the one thing that kills them. then boost them and run them on the lean side with advanced ignition curves and you have a kiln.
it is not the fan. I know this fan pulls more air than the stocker.
I was worried it may be the head gasket because a fiend of mine suggested it may be and wanted me to come over to his shop and test the head with a pressure gauge on the radiator. I would do it if he wouldn't make me do all the work while he made un-funny jokes and got in the way.

I will just ahve to for go some planed mods for a while linger so i can buy a radiator. It's just really bad timing. boss closed shop so I lost my job this week and after some suspension mods I really need an alignment.

We understand that those rotary/Wankel engines have cooling problems, you made that clear. but that doesn't mean it generates more heat than a 4.0. which engine uses more fuel? i'd be inclined to think that the fuel consumed by the engine would be in direct relation to the heat generated by it (impacted very slightly by the efficiency of the engine)

besides, as pointed out, the car moving down the road doesn't require the fan. so the lower speeds are more critical on the fan.

i used to be big on removing stock fans, and replacing them with thermo switched electric fans to "Save horsepower" however, after dealing with the overheating problems, ive moved back to mechanical clutch fan and the overheating problems have gone away (on a variety of cars/trucks)

however if you're confident with the elec fan, which i guess you are, then i'd say upgrade the radiator, and maybe replace the thermostat in case it's jamming. then you can address a head issue if the problem persists.

tweakedlogic · 07-17-2010, 12:15 AM

Quote:

Originally Posted by rhauf

however if you're confident with the elec fan, which i guess you are, then i'd say upgrade the radiator, and maybe replace the thermostat in case it's jamming. then you can address a head issue if the problem persists.

I'm going to do a radiator. I was planning on replacing it anyway but I can't afford that. So I'll buy an OE and toss it in, maybe keep it for a spare after the 3 core upgrade.
Thanks.

*rhauf* · 07-17-2010, 12:21 AM

cool. let us know how it works out.

*Czar Zach* · 07-17-2010, 08:14 PM

I've recently replaced my thermostat, my head gaskets, and i have fluctuating heat problems also. So my next bet would be replacing my radiator, correct?

And if that's the case, would it be better to upgrade to a two core, or is it not too much of a difference than the one?

mr2fix2it · 07-17-2010, 08:35 PM

stop throwing your money away even more so since you dont have any the problem is the fan not the radiator look at the replies and the logic the fan is not made for an EXPLORER this is not a mazda WENKEL

tweakedlogic · 07-18-2010, 12:40 AM

It's not the fan. I really only have a problem when i run the a/c. it has been better the last few days as far as stop lights. I haven't turned on the a/c since the first post. This radiator has over 200,000 miles on it. this is a new body, but under the hood is the same i've been driving for over 5 years. When i pulled this motor from the other body, the a/c didn't work. so I don't ahve a reference point. perhaps, when I run the a/c, i am surpassing the capacity of the old radiator. One of the reasons I opted to use the e-fan is the old fan clutch was shot.
as for the Wankel, it may only be a 1.3 liter (or 2.6 depending on who you ask) but it draws more air than a 5.0. I'm sorry i ever brought it up. but I know it's not the fan.

tweakedlogic · 08-01-2010, 01:32 AM

I found out the 1800-RADIATORS has a local "store". Bought a new rad for $97. Installed it the next day. heat problems gone. I also swapped the t-stat, though i couldn't find a 180 degree model. only 195.
I am considering adding a 10" or smaller fan in front of the condenser just to further aid in cooling when running the a/c.
Thanks guys.

07-14-2010, 06:33 PM	#1
tweakedlogic Wannabe Elite Explorer memphis, tn '92 XLT Join Date: Nov 2003 Posts: 948 Vehicle Specs (Original Poster)	Overheating: Radiator or head gasket? So my truck over heats. I have a stock motor and radiator, w/ 17" electric fan. the first time it happened is after I fixed the A/C. I noticed in stop and go traffic the temp would rise. I never let the needle get above the A in Normal. I would shut off the a/c. I then installed the current 17" fan replacing the 15" fan. It was better for a few weeks. But I did some suspension mods and it has sat for two weeks until today. I was running around town and noticed the temp was already at A. so I shut off the a/c and it started to cool down. I parked for a while and left the e-fan on. got back in and it was @ O. Cool. I left the a/c off, but got stuck behind some traffic for several minutes. I saw the needle start to climb again. the a/c was off. It doesn't use any water and I've never seen any leaking. So, is it a clogged radiator, or a bad head gasket? Gaskets are cheap, but a pain to install. radiators are easy to install, but expensive. I don't know what to do. __________________ 2001 4x4 Sport Trac. it's new to me, so no mods yet. 1992 XLT 4 door 4WD: 32s on 17" Mustang GT rims, 4.56 w/ modified LS in rear, 2.5" lift from F150 coil springs, F250 shock mounts, shackles, Pro comp shocks, hard way rear disc conversion, Ported and polished intake, Dynomax exhaust, e-fan, + other mods I've done since this edit. (Switches, Black,)

07-15-2010, 12:50 PM	#3
jd4242 Elite Explorer va beach 92 SC Join Date: Oct 2008 Posts: 7,095 Vehicle Specs	what fan are you using?the ex needs about/over 3000cfm to stay cool __________________ 92 xl 5.5"duff arms,3"BL,PJ 36x14.50,wrapped headers,side dump exhaust,.20 over,HF oil pump,422cam,45cc 95tm p+p 10.67:1 heads,p+p lower manifold,75mm TB,90mm maf,36lbs injectors,P+P GM M90 Supercharged & intercooled!!SCT tuned!!electric fan,4.88s aussie locked front & back!!next NOS&W/M http://www.explorerforum.com/forums/...=double+vision

07-15-2010, 01:02 PM	#4
Maniak Moderator-Stock 91-94 Vail, Arizona 1992 XLT 4x4 Join Date: Feb 1999 Posts: 10,813 Vehicle Specs	What your describing is not enough airflow. If its fine at say 50mph cruising then its more likely the fan. If at 50mph it overheats then your looking at the radiator.. For head gasket you would have oil in the water, water in the oil and or smoke out the tailpipe. Since your running an electric fan, you really need to make sure its pulling enough cfm. There have been mixed results using the blackmagic fan which pulls "around" 3000 cfm on the 1st gen explorers. It seems to be partly related to how the vehicles are driven and in what climate. ~Mark __________________ Click HERE to see our Explorer Specs

07-15-2010, 06:18 PM	#5
tweakedlogic Wannabe Elite Explorer memphis, tn '92 XLT Join Date: Nov 2003 Posts: 948 Vehicle Specs (Original Poster)	I don't remember the CFM rating. It's the same fan I use in the Rx7. If it's enough for the heat generating rotary @ 8000 RPM on the track, it will be enough for any stump pusher. I don't have any oil in the water, or water in the oil, and no steam from the tail pipe. I guess it must be the radiator. Darn! I didn't want to replace it until I could afford the 2 core triple pass. @ $600, I will have to wait for that and buy a OE. Thanks guys. __________________ 2001 4x4 Sport Trac. it's new to me, so no mods yet. 1992 XLT 4 door 4WD: 32s on 17" Mustang GT rims, 4.56 w/ modified LS in rear, 2.5" lift from F150 coil springs, F250 shock mounts, shackles, Pro comp shocks, hard way rear disc conversion, Ported and polished intake, Dynomax exhaust, e-fan, + other mods I've done since this edit. (Switches, Black,)

07-15-2010, 07:21 PM	#6
rhauf Elite Explorer Ca '93 and '91 explorer Join Date: Nov 2005 Posts: 1,234 Vehicle Specs	get rid of that elec fan and put in a stock clutch fan and shroud.. it'll work way, way, way better. i'd also replace the radiator. i'm just running the best one i could get from autozone and it works great (even towing, even in 100 degrees) of course i'm running the stock fan too.. which whurrs like crazy when its hot. it is possible that it could be a cracked head/blown head gasket just not involving the oil... but id put my money on cooling first. __________________ Check out my Youtube page, many explorer and 4wheelin' videos http://www.youtube.com/user/rhauf1

07-14-2010, 06:42 PM	#2
Ahteixeira4x4 Wannabe Elite Explorer Turlock, Ca 92 XLT Join Date: Jul 2010 Posts: 34 Vehicle Specs	If you have water in your oil than it is your head gasket.

07-15-2010, 08:26 PM	#8
92exp4x4 Elite Explorer Covington, Kentucky 92 XL 2-door and others Join Date: Feb 2003 Posts: 913 Vehicle Specs	Maniak is right, if you are moving at all, then the fan's need to exist goes down. Also the shroud makes a big difference to how much air is pulled through the core of the rad. With no shroud the air can be drawn from between the fan and the rad because it is easier to move it from there. Think the path of least resistence. Also there were two radiators available. A single row core and a 2 row. I have converted all mine over to the 2 row for more capacity. If yours is a two row then the core will be about 2 inches thick. __________________ My stable: 2 doors - '91 Eddie Bauer; '92 XL 5 speed; '92 Sport 2WD 5 speed 4 doors - '91 XLT; '93 XLT; '94 XLT, 6" lift, 33's; '94 Eddie Bauer 5 speed; '94 Limited Others - '22 Model T, '48 8N tractor, '62 Fairlane 500, '93 F-Superduty 460, '97 F250 Powerstroke, '04 F550 service truck (company owned)

07-16-2010, 01:17 AM	#9
tweakedlogic Wannabe Elite Explorer memphis, tn '92 XLT Join Date: Nov 2003 Posts: 948 Vehicle Specs (Original Poster)	I don't think you guys understand the rotary. it makes hellasious heat. the one thing that kills them. then boost them and run them on the lean side with advanced ignition curves and you have a kiln. it is not the fan. I know this fan pulls more air than the stocker. I was worried it may be the head gasket because a fiend of mine suggested it may be and wanted me to come over to his shop and test the head with a pressure gauge on the radiator. I would do it if he wouldn't make me do all the work while he made un-funny jokes and got in the way. I will just ahve to for go some planed mods for a while linger so i can buy a radiator. It's just really bad timing. boss closed shop so I lost my job this week and after some suspension mods I really need an alignment. I do appreciate your help. __________________ 2001 4x4 Sport Trac. it's new to me, so no mods yet. 1992 XLT 4 door 4WD: 32s on 17" Mustang GT rims, 4.56 w/ modified LS in rear, 2.5" lift from F150 coil springs, F250 shock mounts, shackles, Pro comp shocks, hard way rear disc conversion, Ported and polished intake, Dynomax exhaust, e-fan, + other mods I've done since this edit. (Switches, Black,) Last edited by tweakedlogic; 07-16-2010 at 01:23 AM. Reason: deleted things that might mis-construde

07-17-2010, 12:21 AM	#12
rhauf Elite Explorer Ca '93 and '91 explorer Join Date: Nov 2005 Posts: 1,234 Vehicle Specs	cool. let us know how it works out. __________________ Check out my Youtube page, many explorer and 4wheelin' videos http://www.youtube.com/user/rhauf1

07-17-2010, 08:14 PM	#13
Czar Zach Elite Explorer Chino, California 1993 XLT Join Date: Jul 2010 Posts: 45 Vehicle Specs	I've recently replaced my thermostat, my head gaskets, and i have fluctuating heat problems also. So my next bet would be replacing my radiator, correct? And if that's the case, would it be better to upgrade to a two core, or is it not too much of a difference than the one?

07-17-2010, 08:35 PM	#14
mr2fix2it Wannabe Elite Explorer new york 98 sport w/06 mustang 4.0 Join Date: Oct 2003 Posts: 185 Vehicle Specs	stop throwing your money away even more so since you dont have any the problem is the fan not the radiator look at the replies and the logic the fan is not made for an EXPLORER this is not a mazda WENKEL

07-18-2010, 12:40 AM	#15
tweakedlogic Wannabe Elite Explorer memphis, tn '92 XLT Join Date: Nov 2003 Posts: 948 Vehicle Specs (Original Poster)	It's not the fan. I really only have a problem when i run the a/c. it has been better the last few days as far as stop lights. I haven't turned on the a/c since the first post. This radiator has over 200,000 miles on it. this is a new body, but under the hood is the same i've been driving for over 5 years. When i pulled this motor from the other body, the a/c didn't work. so I don't ahve a reference point. perhaps, when I run the a/c, i am surpassing the capacity of the old radiator. One of the reasons I opted to use the e-fan is the old fan clutch was shot. as for the Wankel, it may only be a 1.3 liter (or 2.6 depending on who you ask) but it draws more air than a 5.0. I'm sorry i ever brought it up. but I know it's not the fan. __________________ 2001 4x4 Sport Trac. it's new to me, so no mods yet. 1992 XLT 4 door 4WD: 32s on 17" Mustang GT rims, 4.56 w/ modified LS in rear, 2.5" lift from F150 coil springs, F250 shock mounts, shackles, Pro comp shocks, hard way rear disc conversion, Ported and polished intake, Dynomax exhaust, e-fan, + other mods I've done since this edit. (Switches, Black,)

08-01-2010, 01:32 AM	#16
tweakedlogic Wannabe Elite Explorer memphis, tn '92 XLT Join Date: Nov 2003 Posts: 948 Vehicle Specs (Original Poster)	I found out the 1800-RADIATORS has a local "store". Bought a new rad for $97. Installed it the next day. heat problems gone. I also swapped the t-stat, though i couldn't find a 180 degree model. only 195. I am considering adding a 10" or smaller fan in front of the condenser just to further aid in cooling when running the a/c. Thanks guys. __________________ 2001 4x4 Sport Trac. it's new to me, so no mods yet. 1992 XLT 4 door 4WD: 32s on 17" Mustang GT rims, 4.56 w/ modified LS in rear, 2.5" lift from F150 coil springs, F250 shock mounts, shackles, Pro comp shocks, hard way rear disc conversion, Ported and polished intake, Dynomax exhaust, e-fan, + other mods I've done since this edit. (Switches, Black,)