overheating '68 98 455
#1
overheating '68 98 455
Ok, my 98 has forever had a persistant overheating trouble when at an idle for long peroids,sitting in traffic on warm to hot days. Once the car gets rolling again the temp comes down and everything is good,it's like the car does not exhaust or disapate the heat fast enough and it just builds up under the hood while standing still. Turning on the heat and blower on high helps disapate some heat but isn't really a good thing in summer time, the car never had problems making heat even in the winter.
My dad tried and his mechanic tried numerous things over the years and to this day it is still a problem. The car had another quadcore radiator installed a couple yrs ago,new water pump,heatercore and of course new therm and coolant.
I'm considering a clutch fan which I'm a bit confused about. I understand that the fan would work on a temp controlled clutch and engage at a preset temp and cause the fan to spin at a higher RPM, but at the same time doesn't that cause the motor to turn a higher RPM thus increasing the engine temp?
Years ago, I read an article in one of my Journey w/ Olds news releases that the current type of thermostats were not an effecient at allowing coolant to flow as the typer they were writing about but at the time I couldn't find that specific type and I cannot locat that issue of Journey w/ Olds.
Would eliminating the thermostat be an issue since the car is rarely if ever driven in the winter and could that possibly increase the flow of coolant and not restrict it so there is a constant flow?
Well and thoughts or suggestions?
mike
My dad tried and his mechanic tried numerous things over the years and to this day it is still a problem. The car had another quadcore radiator installed a couple yrs ago,new water pump,heatercore and of course new therm and coolant.
I'm considering a clutch fan which I'm a bit confused about. I understand that the fan would work on a temp controlled clutch and engage at a preset temp and cause the fan to spin at a higher RPM, but at the same time doesn't that cause the motor to turn a higher RPM thus increasing the engine temp?
Years ago, I read an article in one of my Journey w/ Olds news releases that the current type of thermostats were not an effecient at allowing coolant to flow as the typer they were writing about but at the time I couldn't find that specific type and I cannot locat that issue of Journey w/ Olds.
Would eliminating the thermostat be an issue since the car is rarely if ever driven in the winter and could that possibly increase the flow of coolant and not restrict it so there is a constant flow?
Well and thoughts or suggestions?
mike
#2
Hmmm, if it is an AC car it should have the mechanical clutch fan already and it does nothing to idle or engine speed. What Tstat temp is in there? Generally it is not good to eliminate the T stat. What is running hot? Do you have an accurate gauge and is it boiling over?
#4
oldsmaniac, i have 2 clutch fans in my attic that my father had tried over the years. The car does have a/c but it's never used and it currently has a standard fan on it. I also have other fans I guess that were tried over the years different pitch I guess. I remember at one time he had an electric fan mounted in the grill to use when necessary.
so if a clutch fan engages at a set temp,what drives it to spin faster than the idle speed of the belt?
thanks for the quick response you posted.
mike
I can't tell you what therm is in there now it's been so long sine it was replaced, I think 185 and yeas it does boil over.
so if a clutch fan engages at a set temp,what drives it to spin faster than the idle speed of the belt?
thanks for the quick response you posted.
mike
I can't tell you what therm is in there now it's been so long sine it was replaced, I think 185 and yeas it does boil over.
#6
It is not uncommon for the engine temp to climb some when idleing and stop and go traffic. The thermostat sets the operating temperature for the most part. A 185 should keep the engine at that temperature but under certain conditions that temp may go higher. A lower temperature stat would give more time before an overheat condition because you are starting from a lower temp. A worn radiator cap will allow boil over before an actual overheat condition. You still need a good temp gauge to see what exactly the temp is. The clutch fan system allows the fan to run at higher speeds or allows slippage which results in a lower speed. Without slippage by the bimetal spring it will turn at engine speed which will be slower at idle and quicker at driving speeds. The clutch fan blades are usually 6 or 7 while the non clutching fans are possibly only 4 blades. Since the car has Ac there is a condenser in front of the radiator which does restrict air thru the radiator some. I would get a new clutch and put the proper blade on it and see....
#7
Rickman, thank for the tips,never heard of Wetter Water, what is it? Since I don't use the car in winter often, how comfortable does the 160 make if I was to take the car out on a cold (40-50 degrees) day?
mike
mike
#8
oldsmaniac, thanks for the info. I guess i'll try the 160 therm and the new fan assembly, at this point it can't hurt, unfortunately asking dad just what he did when he had the car isn't a possibility, i can only go by parts i have. I know it's been an issue since it was new, i can remember sitting in summer traffic w/ the heater on and my feet roasting,but once we got moving after a few minutes and air flowing the tem dropped and all was normal.
BTW...it boils over into the coolant overflow.
I have to say you guys are quick on the info...this place is awesome!!!
BTW...it boils over into the coolant overflow.
I have to say you guys are quick on the info...this place is awesome!!!
#10
This is scary, and dangerous, but when I was a teenager, I used to check clutch fan function with a long, thin cedar fence plank.
When the car is cold, the fan kind of floats around. if you stick the board between the fan blades, the fan should come to a stop while the engine still spins.
Once the car is up to operating temp, the clutch should go into a lock up mode. If the clutch is working correctly, it should chew the crap out of the end of that cedar plank.
I would never try this method using anything thicker or stronger than thin cedar.
The board must be able to be sacrificed and break off before you get into any trouble with an oldsmobile's torque.
When the car is cold, the fan kind of floats around. if you stick the board between the fan blades, the fan should come to a stop while the engine still spins.
Once the car is up to operating temp, the clutch should go into a lock up mode. If the clutch is working correctly, it should chew the crap out of the end of that cedar plank.
I would never try this method using anything thicker or stronger than thin cedar.
The board must be able to be sacrificed and break off before you get into any trouble with an oldsmobile's torque.
#11
Well, it is supposed to boil over into the overflow and then go back into the radiator when it cools and a vacuum is produced! It is VERY important that the radiator is not over filled. Overfilled would be to the top. There is a line on the radiator maybe 5 inches down that says fill cold. It is still normal at times to have the overflow or recovery tank catch fluid. This is why the radiator cap must be working properly.
#15
Well, it is supposed to boil over into the overflow and then go back into the radiator when it cools and a vacuum is produced! It is VERY important that the radiator is not over filled. Overfilled would be to the top. There is a line on the radiator maybe 5 inches down that says fill cold. It is still normal at times to have the overflow or recovery tank catch fluid. This is why the radiator cap must be working properly.
#16
This is scary, and dangerous, but when I was a teenager, I used to check clutch fan function with a long, thin cedar fence plank.
When the car is cold, the fan kind of floats around. if you stick the board between the fan blades, the fan should come to a stop while the engine still spins.
Once the car is up to operating temp, the clutch should go into a lock up mode. If the clutch is working correctly, it should chew the crap out of the end of that cedar plank.
I would never try this method using anything thicker or stronger than thin cedar.
The board must be able to be sacrificed and break off before you get into any trouble with an oldsmobile's torque.
When the car is cold, the fan kind of floats around. if you stick the board between the fan blades, the fan should come to a stop while the engine still spins.
Once the car is up to operating temp, the clutch should go into a lock up mode. If the clutch is working correctly, it should chew the crap out of the end of that cedar plank.
I would never try this method using anything thicker or stronger than thin cedar.
The board must be able to be sacrificed and break off before you get into any trouble with an oldsmobile's torque.
#17
Silly question has the engine ever been overhauled ? And did they descale the block ? Lots of the older type antifreeze would leave build up. Have also heard of sloppy molds not clean right. just another thought since this seems like a long time thing with the car.
#19
This is scary, and dangerous, but when I was a teenager, I used to check clutch fan function with a long, thin cedar fence plank.
When the car is cold, the fan kind of floats around. if you stick the board between the fan blades, the fan should come to a stop while the engine still spins.
Once the car is up to operating temp, the clutch should go into a lock up mode. If the clutch is working correctly, it should chew the crap out of the end of that cedar plank.
I would never try this method using anything thicker or stronger than thin cedar.
The board must be able to be sacrificed and break off before you get into any trouble with an oldsmobile's torque.
When the car is cold, the fan kind of floats around. if you stick the board between the fan blades, the fan should come to a stop while the engine still spins.
Once the car is up to operating temp, the clutch should go into a lock up mode. If the clutch is working correctly, it should chew the crap out of the end of that cedar plank.
I would never try this method using anything thicker or stronger than thin cedar.
The board must be able to be sacrificed and break off before you get into any trouble with an oldsmobile's torque.
#20
hey o/c thanks for the reply. No I've never hooked up an aux temp guage.
The green/cold light comes on at all cold starts and the red/hot light comes on when its hot. Believe me you can tell when the car is operating at normal temps and is HOT
#21
A 160* thermostat is not going to help your problem it will only postpone it for a few extra minutes. When a thermostat opens, it's temperature control job is finished unless the temp of the engine drops below its rating. What I would suggest is hooking up a temp gauge and see what your temps are actually running.
It seems you have an air flow issue from your description if the radiator was replaced with a direct replacement in capacity.
One more item to consider is tune, is your car tuned up properly? Your tuneup will dramatically effect temp.
And last but not least, it could be a blown head gasket, whereas gases are being pushed into the radiator.
It seems you have an air flow issue from your description if the radiator was replaced with a direct replacement in capacity.
One more item to consider is tune, is your car tuned up properly? Your tuneup will dramatically effect temp.
And last but not least, it could be a blown head gasket, whereas gases are being pushed into the radiator.
#22
An accurate temp. guage would be a given ,since this is not a new problem...Question for you: Has the block been bored over stock dimensions? Has the fuel air mixture been checked for rich/lean burn condition ? Food for thought, as this also can contributed to heating,given that your radiator,pump and fan has already been addressed.. Also, check the preheater flap in the exhaust manifold to insure that it is open when normal operating temps..Don
#23
Has that 45+ year old radiator ever been boiled out??
You are using premium gasoline, aren't you??
Does it run rough, at any time?? [vacuum leak]
Has the radiator ever been checked for blockage in the fins??
Could the timing be too far advanced??
Just a few more things - -
You are using premium gasoline, aren't you??
Does it run rough, at any time?? [vacuum leak]
Has the radiator ever been checked for blockage in the fins??
Could the timing be too far advanced??
Just a few more things - -
#24
Has that 45+ year old radiator ever been boiled out??
You are using premium gasoline, aren't you??
Does it run rough, at any time?? [vacuum leak]
Has the radiator ever been checked for blockage in the fins??
Could the timing be too far advanced??
Just a few more things - -
You are using premium gasoline, aren't you??
Does it run rough, at any time?? [vacuum leak]
Has the radiator ever been checked for blockage in the fins??
Could the timing be too far advanced??
Just a few more things - -
#25
An accurate temp. guage would be a given ,since this is not a new problem...Question for you: Has the block been bored over stock dimensions? Has the fuel air mixture been checked for rich/lean burn condition ? Food for thought, as this also can contributed to heating,given that your radiator,pump and fan has already been addressed.. Also, check the preheater flap in the exhaust manifold to insure that it is open when normal operating temps..Don
hey panther,
how do you know if the preheater is functioning properly?
the block never bored or modified and the car was always kept in tune.
mike
#26
thanks everyone for the suggestions and opinions.
last night,after looking through a USA Parts catalog, I came across something called Hot Water Valve. Never heard of one...for a car at least.
There is one listed for '68-'70 All W/O Auto Temp Control (which my car does not have) for $165.50...
What is a Hot Water Valve and where would/might it be located if I have one and how do I know if it's not functioning?
last night,after looking through a USA Parts catalog, I came across something called Hot Water Valve. Never heard of one...for a car at least.
There is one listed for '68-'70 All W/O Auto Temp Control (which my car does not have) for $165.50...
What is a Hot Water Valve and where would/might it be located if I have one and how do I know if it's not functioning?
#27
The 'pre-heater', or heat riser, [as normally called] should be at the end of the pass. exhaust manifold.
There should be a weight, on the end of a lever, that should be free, when manually pushed.
If seized closed, could be your problem!
The 'hot water valve,' or heater control valve, [normal] is in line with your heater hoses, and should have a vacuum line to it. Opens and closes the circulation of water, going to the heater core!
There should be a weight, on the end of a lever, that should be free, when manually pushed.
If seized closed, could be your problem!
The 'hot water valve,' or heater control valve, [normal] is in line with your heater hoses, and should have a vacuum line to it. Opens and closes the circulation of water, going to the heater core!
#28
You can get one at Advance Auto Parts or AutoZone for less than $50.
When vacuum is applied, the valve opens (though some years are the opposite).
It is screwed into the rearmost corner of the intake manifold on the passenger side.
It has nothing to do with cooling the engine.
- Eric
#30
I am on here searching for reasons my car might be running hot, It runs hotter than I think it should, but it doesn't blow antifreeze out of the overflow tube, just sounds like i can hear the water boiling, i don't loose coolant, it seems like the amount of coolant in there doesn't change like it would be blowing it out. Two things, 1, how would I replace the clutch in the fan if that would be it? Mine had A/C on it, its all there, just no belt going to it, hasn't since I bought the car, so I just want to make sure that I see that, it seems to run cooler when I am on the road and running, it was running and temp would go up and drop down, I replaced the thermostat and now it runs a little hotter and doesn't drop down as far as it did prior to the thermostat being replaced, it is the same, still a 195 thermostat, that is what I pulled out of it.
Another question I have is about spark plugs, I know that when I replaced the plugs just after I got the car were different. I will have to see if I can find the old ones, might be around somewhere, would this possible cause it? Is there such a thing as a "cooler" spark plug?
I am going to check a few other things. Also, this pre-heater flap, how does one fix it, or remove it. I know mine is giving me fits, it starting making noise then might stop, so I am not sure.
Another question I have is about spark plugs, I know that when I replaced the plugs just after I got the car were different. I will have to see if I can find the old ones, might be around somewhere, would this possible cause it? Is there such a thing as a "cooler" spark plug?
I am going to check a few other things. Also, this pre-heater flap, how does one fix it, or remove it. I know mine is giving me fits, it starting making noise then might stop, so I am not sure.
#31
Since this is an AC C body car it may have a TVS (thermostatic vacuum switch) (I know the 1970 model does).
The 1970 service manual talks to the issue of overheating at idle on page 6K9 "When an overheating problem exists at idle speeds only .....", and references the possibility of a non functioning TVS, and shows how to diagnose it.
A working TVS brings full manifold vacuum to the distributor advance when the termperature goes above 223F. This advances the timing, making the engine run cooler.
Also, is it possible Mike does not have enough initial advance?
The 1970 service manual talks to the issue of overheating at idle on page 6K9 "When an overheating problem exists at idle speeds only .....", and references the possibility of a non functioning TVS, and shows how to diagnose it.
A working TVS brings full manifold vacuum to the distributor advance when the termperature goes above 223F. This advances the timing, making the engine run cooler.
Also, is it possible Mike does not have enough initial advance?
#32
I will have to try and find a 70 service manual. I know that i have the TVS, and I have seen parts of it broken/most likely not functioning because they aren't hooked up. If anyone has this in PDF please forward, otherwise I am going to try and find it. Is there a diagram of the vacuum system? I would like to be able to look at it and make sure that system is completley working before going into other areas as I know this is not working.
#35
i was looking online prior to this post and found the following,
http://www.autobooksbishko.com/Items...ual/12830.html
would this be beneficial to me? I like it being on the computer because I can quickly navigate it, and all my other cars I have always had the factory service manual on my computer. Thoughts?
http://www.autobooksbishko.com/Items...ual/12830.html
would this be beneficial to me? I like it being on the computer because I can quickly navigate it, and all my other cars I have always had the factory service manual on my computer. Thoughts?
#36
Both of those are must haves, but if you just want it online you should join Wild About Cars. It is free and has both of those publications as pdf files.
If you find the factory assembly manuals for B or C body cars please let me know.
If you find the factory assembly manuals for B or C body cars please let me know.
#38
So, in looking right away my solenoid is not functioning, it is broken and has no hoses attached to it and a few just laying in there. I have been searching online for this solenoid but can't seem to find one, anyone have any ideas?
#39
You don't need that solenoid. It just allowed the factory to retard the timing more than they should have, in order to reduce oxides of nitrogen. If you set the timing right the first time (according to 1969 specs, or using your ear the old fashioned way), you'll be fine, and possibly run cooler.
Also, change your fan clutch - form what you describe, it sounds like the problem.
- Eric
Also, change your fan clutch - form what you describe, it sounds like the problem.
- Eric
#40
Thanks Eric, I always wondered why they would install those pieces. I imagine that it has been expalined in other threads, but what would the effect be on overall performance in normal daily driving if the distributor vacuum was connected directly to the manifold vacuum rather than ported (eliminating both the TCS solenoid and the TVS).
I guess that having direct manifold vacuum would make the TVS redundant, and eliminating the TCS with manifold vacuum would apply a higher vacuum advance in all gears.
But what is the effect to daily driving of all that?
I guess that having direct manifold vacuum would make the TVS redundant, and eliminating the TCS with manifold vacuum would apply a higher vacuum advance in all gears.
But what is the effect to daily driving of all that?