sneaky_pete
Platinum Member
- Joined
- Aug 10, 2004
- Messages
- 676
- Tractor
- Kubota B7400HSD, G1800
Also, put a gas sniffer up your tailpipe and make sure you're not running lean after installing the FI.
Jeep runs hot (very hot)
- Thread starter stevenf
- Start date
ByronBob
Veteran Member
I rented a new 2005 car this last weekend. It's all digital but at idle the car ran at about 200 degrees. Is 210 a real problem at low idle?
TOMLESCOEQUIP
Platinum Member
Years ago I did the V-8 vega thing & had the same problems you've got. I had a custom 4 core rad, with dual electric fans, etc & still couldn't drive thru town with out a near meltdown. It boiled down(yes it's a pun) to air flow accross the core and with the larger engine, the air couldn't get away under the hood. Try some hood louvers or a reverse cowl type scoop to give the air a place to go & I bet you'll see an improvement. Headers at slow speeds give off bunches of heat.......you may want to use a good header wrap too..............Stay cool........Tom
TOMLESCOEQUIP
Platinum Member
Also........if you don't go with elec. fans, use a good direct drive 7 blade fan (not a clutch fan or a "flex" type racing fan).....You give up a few HP but get to keep your engine............
kensfarm
Veteran Member
I agree.. 210 at idle after running is probably normal. I drive an hour to work.. it's 50 degrees out today. When running on highway.. I'm at 160.. waiting in line at Hardee's this morning.. it jumps to 200+.
On my Firebird RamAir.. there are special bleeders to get rid of air pockets in the cooling system. If your mixture of coolant & water isn't correct.. could cause some heat problems. My auto cooling fans don't kick on until it reaches above the 240 range.
On my Firebird RamAir.. there are special bleeders to get rid of air pockets in the cooling system. If your mixture of coolant & water isn't correct.. could cause some heat problems. My auto cooling fans don't kick on until it reaches above the 240 range.
Snowridge, what a great idea, I'll try it tonight with the electric fan.
Eddie the jeep was built for rock crawling and speed so the manifold was already on it and a big Holley manifold and we didn't need to remove it as the injection system was holley as well and bolted right up. The heat problem has been plagueing me for a while long before injection it was put on to not only improve performance and mileage but in hopes that a better fueled engine would eliminate the overheating at slow speeds low rpm conditions.
As far as the cam I'm frankly not sure and its beyond my mechanical knowledge at this point to change.
I'll try Snowridges idea for a 110 volt fan in front of it tonight at idle and see if that cools it down as that is a wonderfully cheap test and fix as big DC fans can be installed cheaply and easily.
Thanks All, I'll let you know the outcome tonight.
Steve
Eddie the jeep was built for rock crawling and speed so the manifold was already on it and a big Holley manifold and we didn't need to remove it as the injection system was holley as well and bolted right up. The heat problem has been plagueing me for a while long before injection it was put on to not only improve performance and mileage but in hopes that a better fueled engine would eliminate the overheating at slow speeds low rpm conditions.
As far as the cam I'm frankly not sure and its beyond my mechanical knowledge at this point to change.
I'll try Snowridges idea for a 110 volt fan in front of it tonight at idle and see if that cools it down as that is a wonderfully cheap test and fix as big DC fans can be installed cheaply and easily.
Thanks All, I'll let you know the outcome tonight.
Steve
cj7
Gold Member
Steve..
Hello fellow jeeper.
I have a couple of CJ-7 myself that are well belt.
So many post and thoughts here already. So here is mine.
Fan shroud? running with out one cause very poor air-flow
Thermostats can be bought as a high flow.
Timing? has this ever been checked? back it off a couple of degrees and see if that helps.
Does your existing engine fan have a clutch on it? It may be bad and not spinning fast enough to move air at Idle.
4 core rad the is clean with the flowcooler pump should be fine.
You have a tranny cooler already. that is good.
What condition are your hoses in? Are they soft? Do they colapse when you rev the motor? restricing flow?
Rad-cap? 16lb? does it hold pressure?
Do you use and over flow bottle for the coolant?
Pm me with your answers I am happy to help you out any way I can.
I just had a friend move down to Texas not long ago. He has a cj-7 also on coils and 35" tires reall nice jeep. he runs a 318 and 4spd tranny in his. He has had to work out some cooling bugs. Not sure if he is close to you or not.
Hello fellow jeeper.
I have a couple of CJ-7 myself that are well belt.
So many post and thoughts here already. So here is mine.
Fan shroud? running with out one cause very poor air-flow
Thermostats can be bought as a high flow.
Timing? has this ever been checked? back it off a couple of degrees and see if that helps.
Does your existing engine fan have a clutch on it? It may be bad and not spinning fast enough to move air at Idle.
4 core rad the is clean with the flowcooler pump should be fine.
You have a tranny cooler already. that is good.
What condition are your hoses in? Are they soft? Do they colapse when you rev the motor? restricing flow?
Rad-cap? 16lb? does it hold pressure?
Do you use and over flow bottle for the coolant?
Pm me with your answers I am happy to help you out any way I can.
I just had a friend move down to Texas not long ago. He has a cj-7 also on coils and 35" tires reall nice jeep. he runs a 318 and 4spd tranny in his. He has had to work out some cooling bugs. Not sure if he is close to you or not.
RobertN
Super Member
You flushed the block and cooling system with water; did you try any of the flush/cleaners? If it ran cool before, you may have buildups in the system that plain water will not remove.
Did it ever run cool with the new radiator? I wonder if the new radiator is correct for your application? Maybe too small, or has too small of passages. too little surface area?
Has the tranny cooler always ben mounted out front? At low speed/low rpm that could affect air flow.
Although the plugs are new, what do they look like after the engine has run, especially at low speeds/rpm. Check them for a lean condition.
You are running this closed loop on the FI. Where is your O2 sensor for the FI controller mounted? If it is not in the proper place on the header, it could lean out the mixture, especially since you are running open exhaust.
Someone else mentioned hoses; that's a good thing to check. I had that happen once on my old CJ5. the hose was old, and collapsed easily once the coolant was warm. My old V6 had a small heater hose section that blocked or pinched easily, and would cause problems...
The idea about the timing, well worth checking. It could cause it to run hot if it was off. It would also confuse the FI controller and compound the situation.
Most of your replies indicate a worsening condition before most of the mods.
I think, IMHO, I would put new hoses on just because. They're cheap, and good insurance when your miles in the back country. Check the timing; that's cheap and simple to do. Put a good cleaner/flush in the cooling system, or take it to a mechanic; sometimes they have better chemicals and stuff to clean/flush it better.
One thing I did not ask before... Do you have a big Warn 8274 winch in front of the grill blocking flow? A bug screen?
Did it ever run cool with the new radiator? I wonder if the new radiator is correct for your application? Maybe too small, or has too small of passages. too little surface area?
Has the tranny cooler always ben mounted out front? At low speed/low rpm that could affect air flow.
Although the plugs are new, what do they look like after the engine has run, especially at low speeds/rpm. Check them for a lean condition.
You are running this closed loop on the FI. Where is your O2 sensor for the FI controller mounted? If it is not in the proper place on the header, it could lean out the mixture, especially since you are running open exhaust.
Someone else mentioned hoses; that's a good thing to check. I had that happen once on my old CJ5. the hose was old, and collapsed easily once the coolant was warm. My old V6 had a small heater hose section that blocked or pinched easily, and would cause problems...
The idea about the timing, well worth checking. It could cause it to run hot if it was off. It would also confuse the FI controller and compound the situation.
Most of your replies indicate a worsening condition before most of the mods.
I think, IMHO, I would put new hoses on just because. They're cheap, and good insurance when your miles in the back country. Check the timing; that's cheap and simple to do. Put a good cleaner/flush in the cooling system, or take it to a mechanic; sometimes they have better chemicals and stuff to clean/flush it better.
One thing I did not ask before... Do you have a big Warn 8274 winch in front of the grill blocking flow? A bug screen?
ByronBob
Veteran Member
I really don't know if 210 is too hot but if airflow is a concern drive it with the hood off and see if is cooler. You said it's off road most of the time so no hood for a day or 2 won't hurt.