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Topic: Still having overheating problems (Read 2681 times) previous topic - next topic

Still having overheating problems

So some of you may remember my over heating problems i've had with my cougar since I put a new engine in it.  Well that and my wedding plans got put on hold for the last 2 months while i've settled into my new house the fiance and I purchased. 

Anyway basically what is happening now is that the Radiator, cap, thermostat and in the past week a new heater core was put in due to a leak.  I was still fighting what I believe to be a an air lock when I replaced the heater core.  I would every couple of weeks purge the air out of the system and I would be fine for a while.  Now since the heater core it will not build up pressure.  It did once but it was cold pressure.  I cracked the cap open and let the air out.  It will also not pull fluid out of the overflow tank.  I do however have great heat in the car, evidence that there is an air lock somewhere in the system.  I think anyways.  You guys have any ideas?  I'm out of them and it's g me off.  I put the engine in the cougar in July and have only put 4000 miles on it.  In the same time i've put 12000 miles on my pickup.  I really wanna start driving my cougar again.  Please help.

tc
1986 Mercury Cougar -- Midnight Wine and Taupe  ($1700) in 1999 w/ 103,000 miles.  Now with a motor from an 87 with 54K on it.
1988 Mercury Cougar -- Light Sandlewood Metalic  ($40)  in 2003 with 111,000 miles.  Needs a fender, some welding and a good tune up.  Possibly my next daily if i ever get it to the shop.
1991 GMC Sonoma, My $50 daily driver.

Still having overheating problems

Reply #1 –
lack of heat would be a sign of air.

anyway,, with a bone cold motor,, reach for the fan and spin it.  does it go around one full turn?or almost,, if so, its probably the cupert.

are you actually over heating or is it the guage that is telling you?

if your overheating, water should be overflowing out the fill tank andyou would hear it bubbling.

where is the puddle of water landing on the ground?,,below what part of the car?

Still having overheating problems

Reply #2 –
Oh yea.  The fan and clutch are new aswell. 

It's not actually overheating just running near redline.  Old motor always ran with the needle dead verticle and would presureize.  New motor, full system won't pressurize, at least not now.  The radiator cap is always cold, the lower hose is always cold too.  Upperhose is only hot on the bottom.

Yesterday and this morning the needle would redline and then work it's way back down a little.  All afternoon it was between the m and redline.

Also engine is a 3.8.

Thanks for your help.

tc
1986 Mercury Cougar -- Midnight Wine and Taupe  ($1700) in 1999 w/ 103,000 miles.  Now with a motor from an 87 with 54K on it.
1988 Mercury Cougar -- Light Sandlewood Metalic  ($40)  in 2003 with 111,000 miles.  Needs a fender, some welding and a good tune up.  Possibly my next daily if i ever get it to the shop.
1991 GMC Sonoma, My $50 daily driver.

Still having overheating problems

Reply #3 –
is it slightly possible that the Tstat is installed backwards?  the spring loaded end goes down and the point part up on the 3.8.

 i swear that sounds like the problem.  all you have to do on the 87 3.8 is undo the upper hose and reach in the neck and feel for the pointed end. if you feel it, its in there correctly.  another thing,, if the tstat is off center allowing leakage around the rim of its seat it will do this.

Still having overheating problems

Reply #4 –
I'll check it but I don't think the mechanic that did that was that dumb, well for my sake I hope it's not.  I had put in a new tstat when i put the motor in and then the intake manifold popped.  I didn't have the time to do it so i took it to my guy.  I'll be pissed if that's the case though.  It did however have similar problems before it went to that mechanic. 

It's a used engine and my thoughts are that something is clogged or someone once did the head gaskets and i have somethig installed wrong there.

tc
1986 Mercury Cougar -- Midnight Wine and Taupe  ($1700) in 1999 w/ 103,000 miles.  Now with a motor from an 87 with 54K on it.
1988 Mercury Cougar -- Light Sandlewood Metalic  ($40)  in 2003 with 111,000 miles.  Needs a fender, some welding and a good tune up.  Possibly my next daily if i ever get it to the shop.
1991 GMC Sonoma, My $50 daily driver.

Still having overheating problems

Reply #5 –
Any one have any ideas?  I'm at a loss here guys.

tc
1986 Mercury Cougar -- Midnight Wine and Taupe  ($1700) in 1999 w/ 103,000 miles.  Now with a motor from an 87 with 54K on it.
1988 Mercury Cougar -- Light Sandlewood Metalic  ($40)  in 2003 with 111,000 miles.  Needs a fender, some welding and a good tune up.  Possibly my next daily if i ever get it to the shop.
1991 GMC Sonoma, My $50 daily driver.

 

Still having overheating problems

Reply #6 –
Ok so here's an update.  Put in a new thermostat as teh old one could be pushed down on by hand.  Not much but enough to make me nervous.  The result is better but the thing is weird.  It has pressurised once that I know of.  I can now drive it for 2 days straight and the needle never goes over half, and then all of a sudden it goes back to running warm.  Then runs fine for a while and then runs warm.  I'm totally at a loss here.  Out of the blue my mechanic called and wanted to know how it was doing, how ironic?  He said to bring it in and he would look at it for me again and warranty his work since he told me it was fixed. 

Any one got any ideas, I want to fix it my self.  It tickes me off that it's making me mad.

Thanks guys.

tc
1986 Mercury Cougar -- Midnight Wine and Taupe  ($1700) in 1999 w/ 103,000 miles.  Now with a motor from an 87 with 54K on it.
1988 Mercury Cougar -- Light Sandlewood Metalic  ($40)  in 2003 with 111,000 miles.  Needs a fender, some welding and a good tune up.  Possibly my next daily if i ever get it to the shop.
1991 GMC Sonoma, My $50 daily driver.

Still having overheating problems

Reply #7 –
so what if you can manually actuate the tstat by hand?  IF you wanna verify a tstat, tie it to a string and hang it in a pot with water along side a thermometer.  It will open up at the rated temp and you can see it happen.

you mentioned something that makes me also wonder,, if the headgaskets were installed backwards,, that would put the coolant ports on the wrong end.. see pic where i circled.  Those two ports are to be always and forever assumed to go to the rear of the block.  your block actually has two holes in the rear and two identical holes in the front and the same goes for the heads.. 
The headgasket however only has two holes in the rear. 
I have a theory on this and i may be wrong but here it is.  A typical RWD engine sits in a car and rear part is slighty lower than the front.  Water comes in the bottom, thru the block,, and up into the heads via the rear headgasket port,, moving through the heads,, then water crosses over the intake on the rear and front runner ,, then out the tstat housing then back around the radiator,,bla bla bla,, starts over again.
long story short,, your water would infact have to jump an air gap to leap out of the block to get up into the head if the gaskets were backwards so it could make it to the intake. 
Perhaps if your car were to stay pointed down hill all day this overheating would stop,,lol

ofcourse, this is all speculation

Some folks (like me) will port match the headgasket water holes to match the block and head by using care , metal plate and a very share chissel.  I actually had a guy who wanted the other two holes in the front of his 302 head gaskets cut and he had a very cool running motor. 

if they are backwards, perhaps this might be the whole issue with this engine.

another idea
the top of your water pump near where the shaft goes into it, there is a hole.  If you gaze into the hole you can see the silver shaft to the water pump.  there is a seal just beyond that area moving toward the motor.  There should be (on most water pumps) a hole just like it on the bottom side of the water pump.  This is called the Weep Hole.,,,,,,, do you have moisture there?

ok,,,questions
do you have white smoke?
are you adding fluid
does your upper radiator hose get warm or hot?
does your weep hole on the water pump leak?
as for verifying the headgasket orientation,,,, helifino how?

Still having overheating problems

Reply #8 –
a thought just occured to me how to verify if atleast one of yoru headgaskets is backwards. 

remove the coolant temp sensor (single wire sensor) on front driver side intake.

now this might take some doing but get a thin wire like bailing wire size. 
remove the sensor
put a slight bend in the wire about 1''long worth along the end
run the wire with the bend down into the coolant hole
if the headgasket coolant ports are up front, you should be able to run the wire into the driver head and clean down in the block.
if a bunch of wire disappears,, then you may have just found your problem.

perhaps a borescope would be the right tool.

Still having overheating problems

Reply #9 –
Quote
as for verifying the headgasket orientation,,,, helifino how?


Not that it helps here but on a 302 motor you should see the front tabs on the headgaskets sticking out between the block and head.
[SIGPIC][/SIGPIC]

Still having overheating problems

Reply #10 –
good stuff man!!!

I just went out and looked at my 3.8L sitting on the garage floor.  The same principle applies but your heads are 90deg on the forward side and it makes it difficult to verify.  It can be done with a pocket knife or a feeler guage or something flat if you are able to slip it inbetween the head and the gasket.


go check.

Still having overheating problems

Reply #11 –
Cool.  Thanks for the info.  I figured it applied so last night when i was changing my oil I took a quick glance.  It was too dark and the shop light glare was too much in my eye.  Ironically the thing has been great the last couple of days. 

I had an odd theory that may have proved it self, not sure yet but time will tell.  Last summer I rear ended a lady with the cat.  In the process of fixing it the rubber spacers came up missing and i keep forgetting to grab more from the yard or from my parts car every time I'm near either.  I re'adjusted the radiator since it's loose w/o those so that the cap sits slightly higher than the other side of the radiator.  Since then it has been running perfectly normal.  I also think that the replacement upper radiator hose sits slightly higer than the stock one I replaced.  (yes I still had the original on the car after 194k miles.  only replaced it because I thought it was a good idea.  it was still in good shape)

My theory is that since the cap was too low in the system all of the air was getting trapped in the upper hose and the top of the radiator.  Thus not allowing it to pressurize properly but still giving me heat.

Any guesses that could have been the cause this whole time?

tc
1986 Mercury Cougar -- Midnight Wine and Taupe  ($1700) in 1999 w/ 103,000 miles.  Now with a motor from an 87 with 54K on it.
1988 Mercury Cougar -- Light Sandlewood Metalic  ($40)  in 2003 with 111,000 miles.  Needs a fender, some welding and a good tune up.  Possibly my next daily if i ever get it to the shop.
1991 GMC Sonoma, My $50 daily driver.

Still having overheating problems

Reply #12 –
Not saying there's not stupid people out there, but, don't the head gaskets have " FRONT" embossed right on them? All the ones I've done ( all V-8s) did, which unfortunately doesn't mean some J---off didn't put it in bass-ackwards anyway. Flush the cooling system, even just with lots of water , because it could be as simple as contaminents like SILICONE sealer chunks floating around or maybe someone previously dumped 5 or 6 cans of BAR's or some thin' in it & occaisionally lodging in one of the water ports. Also, check compression to verify head gaskets. Final note, how olds the water pump and radiator?

Still having overheating problems

Reply #13 –
Check out the first post in this series.  Everything's new, including pump, rad, fan clutch, all hoses, belt and heater core.  System has been flushed as well, probably 3 times just to make sure.

tc
1986 Mercury Cougar -- Midnight Wine and Taupe  ($1700) in 1999 w/ 103,000 miles.  Now with a motor from an 87 with 54K on it.
1988 Mercury Cougar -- Light Sandlewood Metalic  ($40)  in 2003 with 111,000 miles.  Needs a fender, some welding and a good tune up.  Possibly my next daily if i ever get it to the shop.
1991 GMC Sonoma, My $50 daily driver.

Still having overheating problems

Reply #14 –
stranger thing have happened but i dont think just adding the rubbers on the bottom of the rad could have this drastic of an effect.  Im sure gut instinct tells you the same and thats why your asking.  You confussed your "gut" with "i have a question",,lol.  Happens to me a lot to : )