5.8 getting too hot

blk88lx · 04-27-2003, 11:18 PM

Just put a 351W in my 93 GT and it seems to be running hot. Engine is stock w/155 LPH Fuel pump 24 LBS injectors, GT 40 lower Cobra 5.0 upper. Has new water pump, new 180 thermostat, new radiator cap.

Don't know what temp as I have the stock guage, around town it has gotten up to the O in NORMAL on the guage before I have shut her down. It stays relitavely cool on the highway w/AC on.

What could this be? My 78 Pick up has a 351W cooled by a 302 radiator so my stock 93 radiator should be enough for the 351 in the stang shouldn't it?

lovinspeed01 · 04-28-2003, 12:48 AM

I had a 84 ford ranger that I put a 5.0Litre in, and it had the same problems as you describe. I had a 160 thermostat and a electric fan and it still overheated. I first switched to high performance coolant, then I installed a new water pump(because mine was starting to go) and lastly I took the front fender wells out. I took them out because it really help to draw the hot air from my long tube headers. I believe the fender wells were my problem lied because how tight the motor sat.

Good luck

BilLster · 04-28-2003, 01:47 PM

did you get the reverse rotation water pump ?

WADS56 · 04-28-2003, 02:17 PM

If it will run cool at highway speeds with the AC on but overheat in traffic you need a better fan (assuming you have the correct pump and a stock pulley). What fan do you have now? If it is stock try a new fan clutch or a flex fan. Do you have the fan shroud on? If it all checks out you may need a bigger radiater.

One more thing... using a thermostat that is to cool can cause a car to run hotter sometimes

blk88lx · 04-28-2003, 07:06 PM

I have the stock fan and radiator. Did not have any overheating problems w/the stock engine. I also have the shroud. How do I tell if I have the wrong water pump? air is being pulled into the engine bay.

WADS56 · 04-29-2003, 08:36 AM

If you have a serpintene(sp?) belt you will need a reverse rotation pump.
You did not have cooling problems before because you had a smaller engine that made less heat. I am also guessing that everthing is ok like no coolent leaks, head gaskets sealing, etc... so i would try a flex fan or a real good electric fan.
The reason I am thinking that you need a better fan is because it is fine at highway speeds where there is lots of air flow. At slow speeds the fan may not be moving enough air through the radiater. I would try that first and if it still gets hot you may need to get a bigger radiater. I have the Autozone radiater in my 93 and it works great for a cheap price.

BilLster · 04-29-2003, 09:47 AM

the stock 351 fan turns the oppositit way as a 302

try re routing the belt , this also happens when people try a short belt and dont route it right.

jeff chambers has a good discription of this on his site

. i attached it below

Stang_ROTY · 04-29-2003, 12:18 PM

You're probably going to need a new radiator. The 5.0 stock one is aweful small for a 351. Also, make sure you get a good fan and use the shroud. What water pump are youusing?

Stang951 · 04-29-2003, 06:26 PM

I have / had the same problem with mine....still havent figured out why it runs so damned hot, but I upgraded to a 3G alt, installed a Lincoln Mark VIII fan, 180 t-stat, straight water with 2 bottles of water wetter, Griffin 31X19 aluminum radiator and ended up with temps of 180-220 depending on the heat and the a/c.
I think that I may have problems with the a/c though. My belts are run like this:

And I am using a reverse rotatoion water pump.

The stock 351W fans are made for the standard rotation pumps...I tried that too when I first got the car out of my friends shop. I didnt make it a block before the thing was boiling over. If you use the stock 302 set-up you have to use the 302 fan. With a heavy duty clutch you should not have a problem with airflow.

blk88lx · 04-29-2003, 10:27 PM

stang 951 you're scaring the crap out of me.

I bought a new radiator, mine had all kinds of gunk in it, hopefully that'll get it to cool down.

Mark VIII fan? Dont you mean a Mark VII Fan? If so, why is it better?
I have the stock 93 set up, pretty sure my belt is the same (I still have the air pump)

shovelnose · 04-30-2003, 01:57 AM

I don't think you can mix up 351 to 86-93 5.0 WP, fan, pulley as they have different bolt spacing on the WP.

Mark 8 Fans flow huge amounts of air. 93-96 flow more than the other years. I've read 5000 Cfm or something like that. Also that they draw up to 100 amp on start up and a constant 30 amp. So they put a good draw on the batt/alt.

BilLster · 04-30-2003, 11:12 AM

water pumps use the same housing i can take a pic of the 2 in my basement i use a 351 wp on my 302 to run a short belt and have a 302 wp on my 351 to run the p/s

hopefully it was the rad

Stang951 · 04-30-2003, 12:38 PM

Do you have underdrive pulleys also?
I just remembered that I was told that the underdrives could be contributing to my problem. I dont think that is true, but who knows. Yes the pulley bolts are different also, my friend drilled new holes in my brand new March pulleys to get it to fit on the water pump that they originally got.
You could also check to make sure that you put the head gaskets on correctly, as they could impede water flow. Look at the block where the heads are bolted in the very front. You should see a suqare from the head gasket. If the square is on both side they are both on correctly.

I wonder if there could be blocakages in the the heads or intake causing the water to flow too slowly?

I am thinking of tearing down the motor to dig into it because I think that something may be wrong. Next time I flush the cooling system I am going to try and force the water through with a hose and see how fast the water flow is through the block.
Mine scares me too, but those are upgrades that I was going to do anyway,......just had to do them sooner.

BilLster - yes the housings are the same, bt the position of the actual pump in the housing is different. If you place the two side by side you will see that the 351 pump is set in the housing farther up toward the left and the 302 pump has the pump located lower to the center.

blk88lx · 04-30-2003, 05:24 PM

Replacing the radiator with an autozone one right now...

WADS56 · 04-30-2003, 06:59 PM

Make sure you get the heavy duty one the offer.

04-27-2003, 11:18 PM	#1
blk88lx Registered Member Join Date: Jun 2001 Location: Fort Leonard Wood, MO Posts: 179	5.8 getting too hot Just put a 351W in my 93 GT and it seems to be running hot. Engine is stock w/155 LPH Fuel pump 24 LBS injectors, GT 40 lower Cobra 5.0 upper. Has new water pump, new 180 thermostat, new radiator cap. Don't know what temp as I have the stock guage, around town it has gotten up to the O in NORMAL on the guage before I have shut her down. It stays relitavely cool on the highway w/AC on. What could this be? My 78 Pick up has a 351W cooled by a 302 radiator so my stock 93 radiator should be enough for the 351 in the stang shouldn't it? __________________ 93 GT, 5.8 EFI usual bolt ons, 3.55's, subs, hurst, K+N 78 F100 Short bed, 5.8, dual pipes 4 bbl 03 Sable

04-28-2003, 01:47 PM	#3
BilLster Registered Member Join Date: Oct 2000 Location: Ontario canada Posts: 446	did you get the reverse rotation water pump ? __________________ 89 with 331 t3'/t4 hybrids. upr Suspention worked out finnaly . 9.89 144 mph .

04-28-2003, 02:17 PM	#4
WADS56 gear banger Join Date: Aug 2000 Location: CHICAGO Posts: 1,144	If it will run cool at highway speeds with the AC on but overheat in traffic you need a better fan (assuming you have the correct pump and a stock pulley). What fan do you have now? If it is stock try a new fan clutch or a flex fan. Do you have the fan shroud on? If it all checks out you may need a bigger radiater. One more thing... using a thermostat that is to cool can cause a car to run hotter sometimes __________________ 79 Hatch: NA 347, Stage 2 Canfield Heads, Victor JR. Intake, Blueprinted Holley 750 HP, Solid Roller Cam, Shooting for 10's on motor 93 LX: Tremec, dual friction clutch, fms flywheel, Hedman shorties, O/R H-pipe Ricer hater's club member #49

04-28-2003, 07:06 PM	#5
blk88lx Registered Member Join Date: Jun 2001 Location: Fort Leonard Wood, MO Posts: 179	I have the stock fan and radiator. Did not have any overheating problems w/the stock engine. I also have the shroud. How do I tell if I have the wrong water pump? air is being pulled into the engine bay. __________________ 93 GT, 5.8 EFI usual bolt ons, 3.55's, subs, hurst, K+N 78 F100 Short bed, 5.8, dual pipes 4 bbl 03 Sable

04-29-2003, 08:36 AM	#6
WADS56 gear banger Join Date: Aug 2000 Location: CHICAGO Posts: 1,144	If you have a serpintene(sp?) belt you will need a reverse rotation pump. You did not have cooling problems before because you had a smaller engine that made less heat. I am also guessing that everthing is ok like no coolent leaks, head gaskets sealing, etc... so i would try a flex fan or a real good electric fan. The reason I am thinking that you need a better fan is because it is fine at highway speeds where there is lots of air flow. At slow speeds the fan may not be moving enough air through the radiater. I would try that first and if it still gets hot you may need to get a bigger radiater. I have the Autozone radiater in my 93 and it works great for a cheap price. __________________ 79 Hatch: NA 347, Stage 2 Canfield Heads, Victor JR. Intake, Blueprinted Holley 750 HP, Solid Roller Cam, Shooting for 10's on motor 93 LX: Tremec, dual friction clutch, fms flywheel, Hedman shorties, O/R H-pipe Ricer hater's club member #49

04-28-2003, 12:48 AM	#2
lovinspeed01 Registered Member Join Date: Apr 2003 Location: Alberta, Canada Posts: 46	I had a 84 ford ranger that I put a 5.0Litre in, and it had the same problems as you describe. I had a 160 thermostat and a electric fan and it still overheated. I first switched to high performance coolant, then I installed a new water pump(because mine was starting to go) and lastly I took the front fender wells out. I took them out because it really help to draw the hot air from my long tube headers. I believe the fender wells were my problem lied because how tight the motor sat. Good luck

04-29-2003, 12:18 PM	#8
Stang_ROTY Registered Member Join Date: Feb 2001 Location: Berkshire County - Massachusetts Posts: 735	You're probably going to need a new radiator. The 5.0 stock one is aweful small for a 351. Also, make sure you get a good fan and use the shroud. What water pump are youusing? __________________ Red 1993 GT Street Machine Best E.T. - 12.41/Best MPH = 108 Engine is a 1969 351 block w/393 stroker kit. Dynamic Roller Myte C4, 8 pt cage. Edlebrock Performer heads and Victor Jr. EFI, FRPP 30lb injectors & Cartech fuel system. MSD ignition. Sothside Machine bars & Sub-frames, adj. upper's, 3.73's, Koni rear shocks, much more

04-29-2003, 06:26 PM	#9
Stang951 Registered Member Join Date: Apr 2001 Location: Metairie, La. USA Posts: 132	I have / had the same problem with mine....still havent figured out why it runs so damned hot, but I upgraded to a 3G alt, installed a Lincoln Mark VIII fan, 180 t-stat, straight water with 2 bottles of water wetter, Griffin 31X19 aluminum radiator and ended up with temps of 180-220 depending on the heat and the a/c. I think that I may have problems with the a/c though. My belts are run like this: And I am using a reverse rotatoion water pump. The stock 351W fans are made for the standard rotation pumps...I tried that too when I first got the car out of my friends shop. I didnt make it a block before the thing was boiling over. If you use the stock 302 set-up you have to use the 302 fan. With a heavy duty clutch you should not have a problem with airflow. __________________ Engine: 1990 5.8 / Edelbrock Performer set-up MSD ignition Suspension: Maximum Motorsports Caster-Camber Plates / Maximum Motorsports adjustable lower control arms / FRPP heavy duty upper control arms / Tokico Illumina Shocks and Struts / Ground Pounder Coil Over conversion kit front / Steeda cross brace sub-frame connectors / Drivetrain: Tremec 3550 trans / Steeda Tri-Ax shifter / Spec Stage II clutch and pressure plate / Spec aluminum flywheel / 5.8 in the hole

04-29-2003, 10:27 PM	#10
blk88lx Registered Member Join Date: Jun 2001 Location: Fort Leonard Wood, MO Posts: 179	stang 951 you're scaring the crap out of me. I bought a new radiator, mine had all kinds of gunk in it, hopefully that'll get it to cool down. Mark VIII fan? Dont you mean a Mark VII Fan? If so, why is it better? I have the stock 93 set up, pretty sure my belt is the same (I still have the air pump) __________________ 93 GT, 5.8 EFI usual bolt ons, 3.55's, subs, hurst, K+N 78 F100 Short bed, 5.8, dual pipes 4 bbl 03 Sable

04-30-2003, 01:57 AM	#11
shovelnose Registered Member Join Date: Oct 2000 Location: Ontario, Canada Posts: 234	I don't think you can mix up 351 to 86-93 5.0 WP, fan, pulley as they have different bolt spacing on the WP. Mark 8 Fans flow huge amounts of air. 93-96 flow more than the other years. I've read 5000 Cfm or something like that. Also that they draw up to 100 amp on start up and a constant 30 amp. So they put a good draw on the batt/alt. __________________ 82 Mercury Capri 302, Comp. Cams, Tremec 3550, 3.73's, 12.8@106 N/A Kevin's Capri Kevin's Mustang

04-30-2003, 11:12 AM	#12
BilLster Registered Member Join Date: Oct 2000 Location: Ontario canada Posts: 446	water pumps use the same housing i can take a pic of the 2 in my basement i use a 351 wp on my 302 to run a short belt and have a 302 wp on my 351 to run the p/s hopefully it was the rad __________________ 89 with 331 t3'/t4 hybrids. upr Suspention worked out finnaly . 9.89 144 mph .

04-30-2003, 12:38 PM	#13
Stang951 Registered Member Join Date: Apr 2001 Location: Metairie, La. USA Posts: 132	Do you have underdrive pulleys also? I just remembered that I was told that the underdrives could be contributing to my problem. I dont think that is true, but who knows. Yes the pulley bolts are different also, my friend drilled new holes in my brand new March pulleys to get it to fit on the water pump that they originally got. You could also check to make sure that you put the head gaskets on correctly, as they could impede water flow. Look at the block where the heads are bolted in the very front. You should see a suqare from the head gasket. If the square is on both side they are both on correctly. I wonder if there could be blocakages in the the heads or intake causing the water to flow too slowly? I am thinking of tearing down the motor to dig into it because I think that something may be wrong. Next time I flush the cooling system I am going to try and force the water through with a hose and see how fast the water flow is through the block. Mine scares me too, but those are upgrades that I was going to do anyway,......just had to do them sooner. BilLster - yes the housings are the same, bt the position of the actual pump in the housing is different. If you place the two side by side you will see that the 351 pump is set in the housing farther up toward the left and the 302 pump has the pump located lower to the center. __________________ Engine: 1990 5.8 / Edelbrock Performer set-up MSD ignition Suspension: Maximum Motorsports Caster-Camber Plates / Maximum Motorsports adjustable lower control arms / FRPP heavy duty upper control arms / Tokico Illumina Shocks and Struts / Ground Pounder Coil Over conversion kit front / Steeda cross brace sub-frame connectors / Drivetrain: Tremec 3550 trans / Steeda Tri-Ax shifter / Spec Stage II clutch and pressure plate / Spec aluminum flywheel / 5.8 in the hole

04-30-2003, 05:24 PM	#14
blk88lx Registered Member Join Date: Jun 2001 Location: Fort Leonard Wood, MO Posts: 179	Replacing the radiator with an autozone one right now... __________________ 93 GT, 5.8 EFI usual bolt ons, 3.55's, subs, hurst, K+N 78 F100 Short bed, 5.8, dual pipes 4 bbl 03 Sable

04-30-2003, 06:59 PM	#15
WADS56 gear banger Join Date: Aug 2000 Location: CHICAGO Posts: 1,144	Make sure you get the heavy duty one the offer. __________________ 79 Hatch: NA 347, Stage 2 Canfield Heads, Victor JR. Intake, Blueprinted Holley 750 HP, Solid Roller Cam, Shooting for 10's on motor 93 LX: Tremec, dual friction clutch, fms flywheel, Hedman shorties, O/R H-pipe Ricer hater's club member #49