Can't cool my 360 - The AMC Forum

Author

Share Topic

Topic Search

Topic Options

Fweaky

AMC Apprentice

Joined: May/12/2010
Location: Col Heights, Va
Online Status: Offline
Posts: 20

Quote

Topic: Can't cool my 360
Posted: Jul/22/2010 at 9:20pm

Guys, I come to this forum a lot for info and I usually find it without asking for help. This time I am stumped so thanks in advance for any help or comments you have. I am fighting a heat problem with my 360. I am running it in a 89 Jeep Wrangler. I got the motor out of another Jeep I bought. The previous owner said the motor was out of a 78 Jeep Wagoneer. I can’t seem to cool it down. So far I have spent a ton of money on it with almost no improvement in cooling. I don’t have any indication that I have a blown head gasket. No water in the oil or loss of coolant. No pressure coming back to the radiator. The grill opening is not blocked. I have excellent coolant flow through the radiator that increases with RPM. I have checked the exhaust system to make sure I didn’t have a plugged catalytic converter or exhaust restriction. If I drive on the highway now the faster I go or the more load that is placed on the engine the hotter it gets. At 60 mph the temp hits 230. If I drive around town at 35 mph it stays around 210. Below is what just a few of the things I have tried or changed this year.

1. flowkooler water pump.

2. Heavy duty aluminum radiator from Novak Conversions for AMC V8.

3. 3000 CFM electric fan.

4. Set timing from 0 to 5 degrees of advance with little effect.

5. Run with and without thermostat without any change.

6. Adjusted the carb mixture with no change.

Plus a number of other voodoo fixes that didn't help.

Any thoughts are appreciated.

Nothing is foolproof to a sufficiently talented fool.

poormansMACHINE View Drop Down

Moderator Group

Charter Member

Joined: Jun/28/2007
Location: Carol Stream il
Online Status: Offline
Posts: 9298

Quote

Posted: Jul/22/2010 at 10:08pm

Timing should run between 5 and 10 depending on your fuel. If it can''t cool with a thermostat, then removing it will only prolong the overheat. AMC's aren't prone to blown headgaskets.
Is there a spring in the lower radiator hose to keep it from collapsing at higher rpm?
Sometimes the electric fans are more of a restriction than a help at highway speeds. Who's fan are you running?
What kind of rpm are you running @ 60? Tires/gearing?

Edited by poormansMACHINE - Jul/22/2010 at 10:25pm

I ain't drivin' one of them inbreds! NAMDRA #2923

Fweaky

AMC Apprentice

Joined: May/12/2010
Location: Col Heights, Va
Online Status: Offline
Posts: 20

Quote

Posted: Jul/22/2010 at 11:42pm

I'm not a big fan of running without the thermostat either but it has been at or above 100 degrees here for the past week and I make lots of short trips so it hasn't made a lot of difference. I have a spring in the lower hose. I am presently running 5 degrees of advance. As for the electric fan, I have a proform 2800 CFM fan made for the 5.0 mustang. I also have a flexalite 3000 CFM fan with shroud that I ran on the stock radiator that wouldn't fit the new aluminum radiator. I have a 1500 CFM fan that I ran that doesn't have a shroud and that ran cooler on the highway but not as cool around town. I have even vented the hood to try and give the heat an escape. The gearing the reason I went with the flowkooler pump. I drive a lot on the highway traveling back and forth to the beach so I kept the stock 3.07 gears which keeps the rpm low. I don't do a lot of crawling so its not an issue and with 10 mpg on the highway I need all the help I can get. I run about 2000 rpms at 60 mph.

Nothing is foolproof to a sufficiently talented fool.

purple72Gremlin View Drop Down

Moderator Group

Charter Member

Joined: Jul/01/2007
Location: Illinois
Online Status: Offline
Posts: 7284

Quote

Posted: Jul/22/2010 at 11:49pm

Is the water rusty looking? some V8's would get alot of junk in the water jackets from rust, and then they would run hot. have you tried flushing out the engine? does the cooling system have pressure? if it doesnt, from all what I see here, Id be wondering about a cracked head. Ive had that happen before. radiator cap????? is it good? (New doesnt mean a thing...)

NAMDRA 3349. AMO 8610.
1972 Gremlin V8..and its a D9 wild plum.originally 304/T14.
1979 Spirit/AMX.V8. 304/998.
1982 spirit.

Fweaky

AMC Apprentice

Joined: May/12/2010
Location: Col Heights, Va
Online Status: Offline
Posts: 20

Quote

Posted: Jul/23/2010 at 12:21am

I have flushed the system twice and ran water after each flush for a few hours to clean it out. Both times when I drained it after the flush the water was clean and when I pull the cap now the coolant is clean. The system has pressure and funtions normally, meaning coolant flows out to the overflow as it heats up and back as it cools. I am not losing coolant. I have two caps that work fine and both hold pressure. I am begining to wonder if maybe the motor was rebuilt before I got it and they bored it out and this is causing the problem. I am just trying to pick you guys brains to make sure that I am not missing anything. I know the valve train has some wear and I was thinking about swapping the heads. I just don't want to do that and afterwords find that the block is the problem. I have already spent $1500 trying to solve this problem.

Nothing is foolproof to a sufficiently talented fool.

greaser

AMC Apprentice

Joined: Jun/26/2010
Location: maryland
Online Status: Offline
Posts: 13

Quote

Posted: Jul/23/2010 at 12:46am

Dont' know much about the later motors but are you using V belts or a serpentine system?

Serpentines usually require a reversed water pump..

Are you sure your guage is correct. Double check it with one of those infared guns if can get one.

Is the electric fan running the right way.. Put a piece of paper on the front of the radiator to check..

Timing and mixture will affect temp but normally not make a huge difference..

Gumy

AMC Apprentice

Joined: Apr/14/2010
Location: Netherlands
Online Status: Online
Posts: 29

Quote

Posted: Jul/23/2010 at 1:16am

I've had a similair problemn. The problem started when I reassambled my engine and placed a new dash with Autometer meters. I checked everything and finally came to the conclusion that my engine wasn't running hot but the temperature sending unit was broken... Spend a few € and problem solved... But if your engine is really running hot, then this could not be the solution. But it's worth checking.

Gr Gunther

Fweaky

AMC Apprentice

Joined: May/12/2010
Location: Col Heights, Va
Online Status: Offline
Posts: 20

Quote

Posted: Jul/23/2010 at 3:04am

I am running a V belt (new belts as well) and it is the original set up for the motor. The pump is pumping great. You can see it flowing through the radiator well with the thermostat out. The fan direction is correct. I can hold a sheet of paper in from of the grill and it will suck it out of your hand and against the grill. I am running two temp gauges one is electric and one is mechanical. They are separated by about ten degrees at 160 but by the time they reach 210 they line up together. I have a temperature gun and checked it and they are faily acurate at 210. I had two mechanical gauges so I swapped them out and they both read the same. The engine will vapor lock after you drive it down the road for a while and stop at a long stop light or say you stop for gas so I am sure its really running the temperature the gauges read. I did run this engine in a CJ when I first got it and it may have been running the same temperature then. I just had an old factory gauge that didn't work that great. The only difference then was it wasn't vapor locking. I know that the fuel line runs close to the exhaust now that the motor is in the Wrangler. I have insulated the line but I believe the fuel line is absorbing most of the heat after it leaves the pump and crosses the engine.

I guess what it comes down to is this...If it wasn't vapor locking and I had the same gauge I had in the CJ I would just keep on driving it and never think twice since it probably will need a rebuild soon. I want to be sure that when it either gets rebuilt or replace by another AMC motor that the same problem doesn't continue. I am a die hard AMC fan. I have owned and driven an AMC in one form or another since 1980 so a Chevy or any other motor in my Jeep is not an option.

Nothing is foolproof to a sufficiently talented fool.

abndanger

AMC Nut

Joined: Nov/08/2009
Location: Grand Rapids
Online Status: Offline
Posts: 154

Quote

Posted: Jul/23/2010 at 3:37am

Mark,

After reading the whole post and all that has been done and verified. I would have to concur with you about someone boring it out to much during a rebuild. If the cylinder walls are to thin, it just can't get rid of the heat. Be nice if you could take a head off easily enough to see what's stamped on the top of the piston or remove a plug and maybe a good bore scope you can see what is stamped on the piston.

" LIVING THE AMX DREAM"
1973 AMX Javelin Pierre Cardin

PHAT69AMX

AMC Addicted

Joined: Jul/07/2007
Location: SW Ohio
Online Status: Offline
Posts: 2278

Quote

Posted: Jul/23/2010 at 3:56am

Just a possible thing to maybe try, along the lines of another post.

What type of Distributor ?

How much and how fast of mechanical advance ?

What Vacuum Advance Canister ? Attached to Ported or Manifold vacuum ?

Understanding is more advance sooner can help lower engine temperatures.

As an example, a friend has a '69 Firebird, stock it has a Thermostatic Switch

that changes Vacuum Advance from Ported to Manifold when the engine gets hot.

The additional Vacuum Advance at idle is supposed to cool the engine down.

By the Thermo Switch changing the Vac Adv to Manifold vacuum,

it bumps the advance at idle by a bunch, maybe 10 degrees or more.

Once engine temp drops, Therm Switch changes back to Ported, and advance backs off.

Might try re-curving the Mechancal Advance in your Distributor.

Limit the total mech adv to around 21 to 24 degrees,

and use springs / weights so that it is all-in by 2500 to 3000 rpm.

With only ~24 deg mech adv, the initial can then be bupmed up to 14 to 17 degrees at idle.

Goal being between 34 to 38 degrees Total Advance, Initial plus Mechanical, all in by 3k.

Vacuum Advance from the canister is NOT included in the 34 to 38 deg total.

Vac Adv when the can actuates is added on top of the Initial & Mechanical.

An easy "test" could be changing the Vac Adv Can to Manifold Vacuum

so that it is working at idle, but depending on the Canister, it might dither at idle

if that particular canister requires say 21" of vacuum to give full advance

and the engine idles at say only 15" of vacuum.

Increased adv at idle from either Initial or Vac Adv should also increase manifold vacuum at idle.

Re-curve Distributor for ~24 deg Mechanical Advance all-in by ~2750 engine rpm.

With Vac Adv dis-connected, Set Intitial to ~14 deg at idle ( assuming no mech adv is coming in at idle )

Best way, use a Dial-Back Timing Light to set Total Advance to 34-38 deg at ~3500 rpm,

or an engine rpm level high enough that the mech adv is all-in.

Total Advance, not including Vac Adv, and when it's all-in, is what matters.

What it ends up being at idle is whatever it ends up being.

Use a hand vacuum pump to check that Vac Adv Can is working properly and does not have a ruptured diaphram.

Vac Pump and Dial-Back Timing Light can also be used to check at what vacuum level

the Vac Adv Can starts, when it gives full Vac Adv, and how much Adv it gives.

Then re-connect the Vac Adv, might try it both ways, using Portedf Vac and the using Manifold Vac.

Just something that's kinda easy to try that might make it run cooler, more advance sooner.

Not an exspensive thing to try, and can be easily reversed.

A lean mixture burns slower than a rich mixture, and idle can be the leanest the engine runs.

So more advance at idle allows mixture to fully burn before the exhaust valve opens.

What Carburetor ?

As another post mentions, a lean mixture can also raise engine temperatures.

Link to a Short YouTube Burnout Video

Author	Message Share Topic Printable Version Google Delicious Digg StumbleUpon Windows Live Yahoo Bookmarks reddit Facebook MySpace Newsvine Furl Topic Search Topic Options Post Reply Create New Topic
Fweaky Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: May/12/2010 Location: Col Heights, Va Online Status: Offline Posts: 20	Quote Reply Topic: Can't cool my 360 Posted: Jul/22/2010 at 9:20pm
	Guys, I come to this forum a lot for info and I usually find it without asking for help. This time I am stumped so thanks in advance for any help or comments you have. I am fighting a heat problem with my 360. I am running it in a 89 Jeep Wrangler. I got the motor out of another Jeep I bought. The previous owner said the motor was out of a 78 Jeep Wagoneer. I can’t seem to cool it down. So far I have spent a ton of money on it with almost no improvement in cooling. I don’t have any indication that I have a blown head gasket. No water in the oil or loss of coolant. No pressure coming back to the radiator. The grill opening is not blocked. I have excellent coolant flow through the radiator that increases with RPM. I have checked the exhaust system to make sure I didn’t have a plugged catalytic converter or exhaust restriction. If I drive on the highway now the faster I go or the more load that is placed on the engine the hotter it gets. At 60 mph the temp hits 230. If I drive around town at 35 mph it stays around 210. Below is what just a few of the things I have tried or changed this year. 1. flowkooler water pump. 2. Heavy duty aluminum radiator from Novak Conversions for AMC V8. 3. 3000 CFM electric fan. 4. Set timing from 0 to 5 degrees of advance with little effect. 5. Run with and without thermostat without any change. 6. Adjusted the carb mixture with no change. Plus a number of other voodoo fixes that didn't help. Any thoughts are appreciated.
	Nothing is foolproof to a sufficiently talented fool.

poormansMACHINE Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Charter Member Joined: Jun/28/2007 Location: Carol Stream il Online Status: Offline Posts: 9298	Quote Reply Posted: Jul/22/2010 at 10:08pm
	Timing should run between 5 and 10 depending on your fuel. If it can''t cool with a thermostat, then removing it will only prolong the overheat. AMC's aren't prone to blown headgaskets. Is there a spring in the lower radiator hose to keep it from collapsing at higher rpm? Sometimes the electric fans are more of a restriction than a help at highway speeds. Who's fan are you running? What kind of rpm are you running @ 60? Tires/gearing? Edited by poormansMACHINE - Jul/22/2010 at 10:25pm
	I ain't drivin' one of them inbreds! NAMDRA #2923

Fweaky Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: May/12/2010 Location: Col Heights, Va Online Status: Offline Posts: 20	Quote Reply Posted: Jul/22/2010 at 11:42pm
	I'm not a big fan of running without the thermostat either but it has been at or above 100 degrees here for the past week and I make lots of short trips so it hasn't made a lot of difference. I have a spring in the lower hose. I am presently running 5 degrees of advance. As for the electric fan, I have a proform 2800 CFM fan made for the 5.0 mustang. I also have a flexalite 3000 CFM fan with shroud that I ran on the stock radiator that wouldn't fit the new aluminum radiator. I have a 1500 CFM fan that I ran that doesn't have a shroud and that ran cooler on the highway but not as cool around town. I have even vented the hood to try and give the heat an escape. The gearing the reason I went with the flowkooler pump. I drive a lot on the highway traveling back and forth to the beach so I kept the stock 3.07 gears which keeps the rpm low. I don't do a lot of crawling so its not an issue and with 10 mpg on the highway I need all the help I can get. I run about 2000 rpms at 60 mph.
	Nothing is foolproof to a sufficiently talented fool.

purple72Gremlin Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Charter Member Joined: Jul/01/2007 Location: Illinois Online Status: Offline Posts: 7284	Quote Reply Posted: Jul/22/2010 at 11:49pm
	Is the water rusty looking? some V8's would get alot of junk in the water jackets from rust, and then they would run hot. have you tried flushing out the engine? does the cooling system have pressure? if it doesnt, from all what I see here, Id be wondering about a cracked head. Ive had that happen before. radiator cap????? is it good? (New doesnt mean a thing...)
	NAMDRA 3349. AMO 8610. 1972 Gremlin V8..and its a D9 wild plum.originally 304/T14. 1979 Spirit/AMX.V8. 304/998. 1982 spirit.

Fweaky Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: May/12/2010 Location: Col Heights, Va Online Status: Offline Posts: 20	Quote Reply Posted: Jul/23/2010 at 12:21am
	I have flushed the system twice and ran water after each flush for a few hours to clean it out. Both times when I drained it after the flush the water was clean and when I pull the cap now the coolant is clean. The system has pressure and funtions normally, meaning coolant flows out to the overflow as it heats up and back as it cools. I am not losing coolant. I have two caps that work fine and both hold pressure. I am begining to wonder if maybe the motor was rebuilt before I got it and they bored it out and this is causing the problem. I am just trying to pick you guys brains to make sure that I am not missing anything. I know the valve train has some wear and I was thinking about swapping the heads. I just don't want to do that and afterwords find that the block is the problem. I have already spent $1500 trying to solve this problem.
	Nothing is foolproof to a sufficiently talented fool.

greaser Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Jun/26/2010 Location: maryland Online Status: Offline Posts: 13	Quote Reply Posted: Jul/23/2010 at 12:46am
	Dont' know much about the later motors but are you using V belts or a serpentine system? Serpentines usually require a reversed water pump.. Are you sure your guage is correct. Double check it with one of those infared guns if can get one. Is the electric fan running the right way.. Put a piece of paper on the front of the radiator to check.. Timing and mixture will affect temp but normally not make a huge difference..

Gumy Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: Apr/14/2010 Location: Netherlands Online Status: Online Posts: 29	Quote Reply Posted: Jul/23/2010 at 1:16am
	I've had a similair problemn. The problem started when I reassambled my engine and placed a new dash with Autometer meters. I checked everything and finally came to the conclusion that my engine wasn't running hot but the temperature sending unit was broken... Spend a few € and problem solved... But if your engine is really running hot, then this could not be the solution. But it's worth checking. Gr Gunther

Fweaky Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Apprentice Joined: May/12/2010 Location: Col Heights, Va Online Status: Offline Posts: 20	Quote Reply Posted: Jul/23/2010 at 3:04am
	I am running a V belt (new belts as well) and it is the original set up for the motor. The pump is pumping great. You can see it flowing through the radiator well with the thermostat out. The fan direction is correct. I can hold a sheet of paper in from of the grill and it will suck it out of your hand and against the grill. I am running two temp gauges one is electric and one is mechanical. They are separated by about ten degrees at 160 but by the time they reach 210 they line up together. I have a temperature gun and checked it and they are faily acurate at 210. I had two mechanical gauges so I swapped them out and they both read the same. The engine will vapor lock after you drive it down the road for a while and stop at a long stop light or say you stop for gas so I am sure its really running the temperature the gauges read. I did run this engine in a CJ when I first got it and it may have been running the same temperature then. I just had an old factory gauge that didn't work that great. The only difference then was it wasn't vapor locking. I know that the fuel line runs close to the exhaust now that the motor is in the Wrangler. I have insulated the line but I believe the fuel line is absorbing most of the heat after it leaves the pump and crosses the engine. I guess what it comes down to is this...If it wasn't vapor locking and I had the same gauge I had in the CJ I would just keep on driving it and never think twice since it probably will need a rebuild soon. I want to be sure that when it either gets rebuilt or replace by another AMC motor that the same problem doesn't continue. I am a die hard AMC fan. I have owned and driven an AMC in one form or another since 1980 so a Chevy or any other motor in my Jeep is not an option.
	Nothing is foolproof to a sufficiently talented fool.

abndanger Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Nut Joined: Nov/08/2009 Location: Grand Rapids Online Status: Offline Posts: 154	Quote Reply Posted: Jul/23/2010 at 3:37am
	Mark, After reading the whole post and all that has been done and verified. I would have to concur with you about someone boring it out to much during a rebuild. If the cylinder walls are to thin, it just can't get rid of the heat. Be nice if you could take a head off easily enough to see what's stamped on the top of the piston or remove a plug and maybe a good bore scope you can see what is stamped on the piston.
	" LIVING THE AMX DREAM" 1973 AMX Javelin Pierre Cardin

PHAT69AMX Members Profile Send Private Message Find Members Posts Add to Buddy List AMC Addicted Joined: Jul/07/2007 Location: SW Ohio Online Status: Offline Posts: 2278	Quote Reply Posted: Jul/23/2010 at 3:56am
	Just a possible thing to maybe try, along the lines of another post. What type of Distributor ? How much and how fast of mechanical advance ? What Vacuum Advance Canister ? Attached to Ported or Manifold vacuum ? Understanding is more advance sooner can help lower engine temperatures. As an example, a friend has a '69 Firebird, stock it has a Thermostatic Switch that changes Vacuum Advance from Ported to Manifold when the engine gets hot. The additional Vacuum Advance at idle is supposed to cool the engine down. By the Thermo Switch changing the Vac Adv to Manifold vacuum, it bumps the advance at idle by a bunch, maybe 10 degrees or more. Once engine temp drops, Therm Switch changes back to Ported, and advance backs off. Might try re-curving the Mechancal Advance in your Distributor. Limit the total mech adv to around 21 to 24 degrees, and use springs / weights so that it is all-in by 2500 to 3000 rpm. With only ~24 deg mech adv, the initial can then be bupmed up to 14 to 17 degrees at idle. Goal being between 34 to 38 degrees Total Advance, Initial plus Mechanical, all in by 3k. Vacuum Advance from the canister is NOT included in the 34 to 38 deg total. Vac Adv when the can actuates is added on top of the Initial & Mechanical. An easy "test" could be changing the Vac Adv Can to Manifold Vacuum so that it is working at idle, but depending on the Canister, it might dither at idle if that particular canister requires say 21" of vacuum to give full advance and the engine idles at say only 15" of vacuum. Increased adv at idle from either Initial or Vac Adv should also increase manifold vacuum at idle. Re-curve Distributor for ~24 deg Mechanical Advance all-in by ~2750 engine rpm. With Vac Adv dis-connected, Set Intitial to ~14 deg at idle ( assuming no mech adv is coming in at idle ) Best way, use a Dial-Back Timing Light to set Total Advance to 34-38 deg at ~3500 rpm, or an engine rpm level high enough that the mech adv is all-in. Total Advance, not including Vac Adv, and when it's all-in, is what matters. What it ends up being at idle is whatever it ends up being. Use a hand vacuum pump to check that Vac Adv Can is working properly and does not have a ruptured diaphram. Vac Pump and Dial-Back Timing Light can also be used to check at what vacuum level the Vac Adv Can starts, when it gives full Vac Adv, and how much Adv it gives. Then re-connect the Vac Adv, might try it both ways, using Portedf Vac and the using Manifold Vac. Just something that's kinda easy to try that might make it run cooler, more advance sooner. Not an exspensive thing to try, and can be easily reversed. A lean mixture burns slower than a rich mixture, and idle can be the leanest the engine runs. So more advance at idle allows mixture to fully burn before the exhaust valve opens. What Carburetor ? As another post mentions, a lean mixture can also raise engine temperatures.
	Link to a Short YouTube Burnout Video