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Pages: 1

Please Help Me

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Posted by: SPECTRE2147

I Got A 93 And Think I Need To Replace My Heater Core, She Been Overheating For About A Month Now, And I've Replaced A Lot To Do With The Cooling System, All To No Avail. Im Merely Seeking Some Advice About This This Let Me Go Into Better Detail.

My Car Overheats While Driving, Cools Down At Idle?
I've Replaced The T/s, Water Pump, Radiator, And Temp Sensor To The Gauge.
Ive Taken Off The Intake Tube To Have A Look At The Heater Core Hoses, And Didnt See Any Signs Of Leakage, However I Did Notice That The Hoses Didnt Have The Factory Clamps On Them, What I Need To Know Is How To Replace The Heater Core, So That I Can Have A Better Look At This, Coolant Is Going Somewhere, And Shes Now Putting A Small Spot On The Road When Its Cooling Off At Work.
My 93 Mark Viii Has 64000 Miles On It, Im Hoping Uts Just An Old Hose, But It Doesnt Look Like The Case. Anyone Else Ever Has This Problem?

Posted by: unity

You could try to double-clamp all the hoses. Not the best idea, but that could narrow the leak when it comes to hoses.

If you have a spot, you have a leak location though. You need to narrow that.

If the core was leaking, odds are it would leak into the interior and you would smell it.

Posted by: slowmkviii

Fallow the coolant from the ground up

Posted by: NYC LS8

I would also pressure test the system to find any leaky hoses and go from there. The heater core should be the LAST thing you'd want to do on this car....or any Ford for that matter.

Posted by: mafioso

Also check the twin speed fan, If its not running on High, aka when driving the hot gasses and fuild will leak out form a failure point.

I faught with that problem until I replaced the fan, and the issue corrected itself.

Posted by: JMiles_T

Replacing the heater core is very time consuming; it requires disassembling the dashboard.

Do you actually have evidence that the core is leaking (fog on windows, antifreeze smell in passenger compartment)?

If you go through all that work, and the heater core ends up not being the location of the leak, you're going to end up being really pi$$ed.

You can try bypassing it for the time being. You won't have heat in the car but it may save you a headache.

If the coolant still leaks after you've bypassed the core, you'll know that the heater isn't where the leak is.

The two black pipes at the back of the engine on the passenger side lead to the heater core. Connect them with 1 hose, and see if it still leaks.

Posted by: JMiles_T

The last 2 causes of overheating on my own car:

1.Radiator fan motor wore out and didn't spin the blades at full speed. It only overheated when the car sat with the engine running.

2. My last coolant leak was at the crossover tube cap. The o-ring wasn't sealing the system properly and coolant kept escaping at the cap. I replaced the o-ring with a slightly thicker one from Ace Hardware. I lubricated it with Dielec. grease before I tightened the cap. In addition, I rubbed Red RTV on the cap threads and pipe threads before I tightened it down. The problems ended there.

When the system's working properly, during cold months like this, my temperature gauge will read at the bottom of the "L" in N-O-R-M-A-L and no higher than the crossbar of the "A".

Posted by: SPECTRE2147

Well, I Dont Smell Antifreeze Inside The Vehicle, No Foggy Windows, So It May Not Be My Core, I Just Noticed Some Coolant On The Round, Sitting In The Drivers Seat, The Location Would Be Rear Engine, Passenger Side. Any Guesses?

Posted by: unity

Rear passenger side?

Could be heater core hoses - very likely, or it could be the heater core input, it comes off the back of the head. There is an o-ring with that. But usually that part gets "Sealed" up from age.

My bet is on the heater core hoses if thats where the leak is. Get a flash light and look really close.

Posted by: SPECTRE2147

Okay, Im Hoping(not Really) That This Is The Problem, Right Now I Just Wanna Know What The Problem Is, Im Gonna Be More Than Happy To Fix It At This Point.

Posted by: NateRW21

Might save you some time typing if you didn't capitalize the first letter of every word. Just giving you a tip; if caps is what you prefer then by all means...

Posted by: SPECTRE2147

your funny, i type at 102 wpm, so i need some challenges

Posted by: unity

Well the caps were getting annoying

Well let us know what you find. I sorta hope is is the heater hose, then you know where the problem is. Then again, I hope not since they are a complete pain to replace. Damn Ford for designing this car around a V6!

Posted by: 93' Blue on blue

Quote:

Originally Posted by SPECTRE2147

your funny, i type at 102 wpm, so i need some challenges

A spooky challenge for you:

http://www.novelgames.com/flashgames/game.php?id=32

Posted by: mafioso

Mark VIII's where designed with a V6 in mind?

Posted by: unity

Unfortunately yes. The entire MN12 platform was built for a V6 - fuel economy in mind. But competition for Cadillac and such forced for to play the modular card and the "all new" 4.6L made it in almost at the last minute.

This is why working on it can be rather difficult. The heater core, oil filter, throttle body, etc.... Also the reason for the tight clearances everywhere else.

Needless to say, I would rather have to "put up" with a V8 shoed in there than a V6.

Posted by: mafioso

No doubt considering the curb weight, it would be a dog, unable to escape its own shadow, just like my xB.

Posted by: Markviiiedrea

Just do like JMILES T said and by-pass the the heater core to elimanate the heater core, go to the auto parts store an buy a 12in peice of 1/2 heater hose and conect in inlet with the oulet.

Posted by: turborich

does your car have the air deflector under the bumper? If not this could be why it heats up while driving.

Posted by: unity

Quote:

Originally Posted by turborich

does your car have the air deflector under the bumper? If not this could be why it heats up while driving.

I dont have one and my temp never fluctuates.

Posted by: SPECTRE2147

Quote:

Originally Posted by 93' Blue on blue

A spooky challenge for you:

http://www.novelgames.com/flashgames/game.php?id=32

cool game

Posted by: 93' Blue on blue

Lol. Im only at around 10,000 points

My wife is good at it though!

Posted by: mespock

I may be wrong but I was told that it would be rare for the Mark VIII heater core to go bad. It is a straight through designe from what I was told.

Posted by: NateRW21

This is very odd...

Overheating when driving, cooling down when idling. And you're puddling on the ground... Plus you've replaced your thermostat, radiator and temp sensor... That sum it up?

Okay, so... I think the first issue to address is your leak. Try to trace it up from the ground. You could have a manifold leak (check on the back side if you can; see if it's damp), leaking hose (although I think you'd notice that). I'd be surprised if it's your heater core given the fact that it's dry inside your car, lacking the sweet smell of glycol.

Also, throw a new cap on your system. It's essential that the correct pressure be maintained in your system for it to work at top efficiency.

Posted by: 93zzzt

try the cap. also might want to check for engine compression in the radiator, for example blown head gasket.

had a problem on a mustang and took us a while to figure it out, we were getting combustion products in the coolant. easy to fixxor. good luck.

Posted by: turborich

You may need to get a air deflector. My car ran hot while on the freeway but would cool down while in town, Yeah I know kinda ass backwards like your car is doing. Since I put the air deflector back on I have had no overheating issues, even in the 118 degree + weather.

Posted by: SPECTRE2147

Any Suggestions On Where To Get Said Air Deflector?

Posted by: SPECTRE2147

Thank God For Tax Season! Im Probably Gonna Dunp My Shole Return In This Problem, Just Gettin Ready For That Bullsh&&.

Posted by: rrudd2

Two questions...

First, have you properly "burped" the system at the cross-over tube? You've done a lot to the cooling system that could allow an air pocket into the system.

Second, have you verified that the high-speed fan is running?

I had a similar problem with one of my 93's. It would overheat at road speed, then cool down fine at idle.

It turned out that the VCRM went bad. The VCRM controls the high-speed fan. The fan wouldn't come on, and the car would overheat while driving.

With the car idling, turn on the air conditioning to MAX AC. The fan should start up immediately. If it doesn't, then you've got an issue with either your fan or with the VCRM.

The coolant leak is a problem, but it may not be THE problem.

Posted by: mespock

Quote:

Originally Posted by unity

Needless to say, I would rather have to "put up" with a V8 shoed in there than a V6.

If the Mark VIII was a V-6 I'd be driving something different...

Posted by: slowmkviii

Quote:

Originally Posted by unity

Unfortunately yes. The entire MN12 platform was built for a V6 - fuel economy in mind. But competition for Cadillac and such forced for to play the modular card and the "all new" 4.6L made it in almost at the last minute.

This is why working on it can be rather difficult. The heater core, oil filter, throttle body, etc.... Also the reason for the tight clearances everywhere else.

Needless to say, I would rather have to "put up" with a V8 shoed in there than a V6.

I would say the mn12 was made for the six but the fn10 was the test bed for the 4.6 dohc

Posted by: 93' Blue on blue

I thought the Town Car was the 'test bed' for the 4.6 DOHC.

Posted by: unity

Actually the Mark IS an FN10 platform, which is a variant of the MN12. Since they are so close, a lot of people refer to the FN10 as an MN12.

Posted by: JMiles_T

Quote:

Originally Posted by 93' Blue on blue

I thought the Town Car was the 'test bed' for the 4.6 DOHC.

The Town Car got the 4.6 SOHC.

Posted by: 93' Blue on blue

Not what i meant. Before the Mark VIII came along, i read somewhere that the DOHC was fitted to a bunch of Town Cars for pre - production testing.

Posted by: kustomizingkid

I have heard of a few different panthers getting the DOHC motor. The only one that made it to production though was the Marauder.

Posted by: SPECTRE2147

It turned out that the VCRM went bad. The VCRM controls the high-speed fan. The fan wouldn't come on, and the car would overheat while driving.

With the car idling, turn on the air conditioning to MAX AC. The fan should start up immediately. If it doesn't, then you've got an issue with either your fan or with the VCRM.

WHAT DOES VCRM STAND FOR? AND WHERE MIGHT IT BE SO I CAN FIND IT TO REPLACE IF NECESSARY?

Posted by: rrudd2

Quote:

Originally Posted by SPECTRE2147

WHAT DOES VCRM STAND FOR? AND WHERE MIGHT IT BE SO I CAN FIND IT TO REPLACE IF NECESSARY?

I believe VCRM stands for Variable Control Relay Module. On a 93, it's located in front of the radiator, down towards the bottom. It's got fins for cooling and a pretty large electrical connector attached to it.

I got mine from Jamie, via eBay.

Posted by: unity

A new one is apparently hard to come by. There was a new article about older cars and how a Mark VIII owner no longer had a usable car because the VCRM went bad and no one had one. Apparently he never heard of a salvage yard and apparently is was news worthy! lol

Posted by: kustomizingkid

Quote:

Originally Posted by unity

A new one is apparently hard to come by. There was a new article about older cars and how a Mark VIII owner no longer had a usable car because the VCRM went bad and no one had one. Apparently he never heard of a salvage yard and apparently is was news worthy! lol

Or possibly the idea that you could put a temp controlled relay going straight to the fan....

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