Oil temps
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Joined: Dec 2001
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From: Hannibal, Missouri
Oil temps
My stock 84 has a problem with the oil temps. When I am sitting idleing or going slow, the temps will rise. They have got to 250+ before. If I am on the highway or driving steady, they seem to stay down about 210 -220. My coolant temps usually only reach about 190-200, even when the oil is well above that. Is this normal? This car does not have an oil cooler and I really can't afford to buy one at this time.
Another problem is when the oil starts to get around the 250 mark, sometimes the car will stall and not restart for about five minutes. It will crank fine but will not start. That also happens when I drive for a while, get everything good and warmed up, shut it off and try to restart within a couple of minutes. I have to wait about five minutes before it will start. I don't have anyway to test the fuel pressure.
Anybody have any ideas on what these problems could be and how to fix them?
Also, there are no codes.
Thanks
Another problem is when the oil starts to get around the 250 mark, sometimes the car will stall and not restart for about five minutes. It will crank fine but will not start. That also happens when I drive for a while, get everything good and warmed up, shut it off and try to restart within a couple of minutes. I have to wait about five minutes before it will start. I don't have anyway to test the fuel pressure.
Anybody have any ideas on what these problems could be and how to fix them?
Also, there are no codes.
Thanks
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
Almost sounds like vapor lock. 250 is pretty damn high. Do you have room for an add-on oil cooler? Coolant temps seem in an acceptable range.
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From: Hannibal, Missouri
Somebody told me before that it could be vapor lock. They told me to put wooden close pins on the fuel line to act as heat sinks but that didn't make a difference. Any other ideas on how to fix it?
I am sure there is room for an oil cooler but my funds are short right now so that is not an option in the near future. I was hoping maybe somebody had some ideas why they were so high. My daughter, who just got her drivers license, wants to drive it in the 4th of july parade but I am afraid it will get too hot and stall on her in the middle of the parade and then not restart. That would be quite embarassing.
I am sure there is room for an oil cooler but my funds are short right now so that is not an option in the near future. I was hoping maybe somebody had some ideas why they were so high. My daughter, who just got her drivers license, wants to drive it in the 4th of july parade but I am afraid it will get too hot and stall on her in the middle of the parade and then not restart. That would be quite embarassing.
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Joined: Sep 2000
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From: The Top of Utah
I think the two problems are unrelated. In warm weather I routinely see oil temps of 230° and over. I can't recall the highest I've ever seen, maybe close to 250°. Your coolant temps are cool. The '84's never had an engine oil cooler available as an option. Is there good air flow around the engine? Is it caked with gunk, that would impede cooling, especially on or around the oil pan?
When the engine stalls, something it needs, air, fuel, or spark, is going away. You need to test and diagnose which it is. I'm guessing that it isn't the air.
RACE ON!!!
When the engine stalls, something it needs, air, fuel, or spark, is going away. You need to test and diagnose which it is. I'm guessing that it isn't the air.
RACE ON!!!
Le Mans Master
Joined: Feb 2005
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From: The Motor City
Is the temp. you indicate from the dash gauge, or another source?
I read CFI's comment and I believe him. I never thought the factory cooler would change the temp. that much.
Mine w/factory cooler and on a 98*+ day, goes to 200-202*(very close to w.temp). Difference is once the oil is at that temp. it pretty much stays there regardless of w.temp. going down.
I read CFI's comment and I believe him. I never thought the factory cooler would change the temp. that much.
Mine w/factory cooler and on a 98*+ day, goes to 200-202*(very close to w.temp). Difference is once the oil is at that temp. it pretty much stays there regardless of w.temp. going down.
Team Owner
Joined: Aug 2000
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From: San Pedro CA
I would wonder if there is a fuel delivery problem.
however, being a "fuel injected" engine, I would be surprised if it was vapour lock... the PSI is high enough to keep that from happening.
however, being a "fuel injected" engine, I would be surprised if it was vapour lock... the PSI is high enough to keep that from happening.
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
I have an engine oil cooler and my coolant and oil temp stay within 10 degrees of each other. I am assuming that keeping oil temps down will help the fuel delivery or whatever is causing the dying and starting problem. I was really just thinking out loud....fix the oil temp issue which is probably a circulation/cooling issue would be my first concern.
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From: Hannibal, Missouri
Thanks everybody for your answers and suggestions. I am going to have to get it on a rack and see how badly it is gunked up on the bottom. I need to change the oil, if I use synthetic oil would that make a difference? I don't know if the two problems are related but I am sure the heat has something to do with it stalling and not starting.
CFI, are you saying that it is not possible to put an oil cooler on the 84's? Or is it just not an easy task?
CFI, are you saying that it is not possible to put an oil cooler on the 84's? Or is it just not an easy task?
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Race Director
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From: SCMR Rat Pack'r Charter Member..Great Bend KS
An oil temp of 250degrees would not alarm me...IF it were synthetic oil.
My oil temp typically runs 20-25degrees higher than coolant temps on my C4...which would put it around 230 on the highway.
I've seen it approach 270degrees when flogged.
Larry
code5coupe
My oil temp typically runs 20-25degrees higher than coolant temps on my C4...which would put it around 230 on the highway.
I've seen it approach 270degrees when flogged.
Larry
code5coupe
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From: Alpine California
Originally Posted by rocco16
An oil temp of 250degrees would not alarm me...IF it were synthetic oil.
My oil temp typically runs 20-25degrees higher than coolant temps on my C4...which would put it around 230 on the highway.
I've seen it approach 270degrees when flogged.
Larry
code5coupe
My oil temp typically runs 20-25degrees higher than coolant temps on my C4...which would put it around 230 on the highway.
I've seen it approach 270degrees when flogged.
Larry
code5coupe
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Joined: Dec 2001
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From: Hannibal, Missouri
So I would be better off using synthetic oil? I can do that. I am going to change oil this weekend, I will use the synthetic and see if it makes a difference. Any suggestions on which is the best brand to use? Do I need a special filter or will a regular one work? I am also still going to make sure the ouside of the engine is not all gunked up.
Le Mans Master
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From: One day you're a Comet...the next day you're dust... Arkansas
Synthetic oil like Mobil 1 will not break down as fast as dino at high temps.
With it being summer I would go to 10w-30 Mobil 1 and the largest capacity oil filter for your year. That should help some. I still think 250 is too high and you should pursue a cure.
With it being summer I would go to 10w-30 Mobil 1 and the largest capacity oil filter for your year. That should help some. I still think 250 is too high and you should pursue a cure.
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From: The Top of Utah
Originally Posted by MFP
CFI, are you saying that it is not possible to put an oil cooler on the 84's? Or is it just not an easy task?
, or install a true cooler available from the aftermarket. I'd take a close look at the tune and dirt and see if you can't avoid the project. Your water temps are OK, but you might try a 180° thermostat, to see of they won't drop both the water and oil temps. Unless you are racing (track, not drags) you really shouldn't need any kind of an engine oil cooler. Synthetic oil won't lower the oil temps, but it will tolerate higher temps better.
Originally Posted by Blownfuel1
I agree with Larry, without an oil cooler, it's perfectly normal for oil temp's to run 25 or more degrees hotter than water temp's, I'm not sure how big of a difference is normal with a cooler installed, but oil temp's usually run a little hotter that water temp's do.
RACE ON!!!