Not wanting it to be a head gasket

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tekrsq

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99 EB, 5/4, 212,000 miles. For about the last 8 months or so, I have noticed that my engine has been running higher temps than normal.........especially when pulling a trailer. With a 195F thermostat, the truck normally runs 195-200F...occassionally at 205 if it's a 100+ degree day. Temps when pulling about 5000 lbs will sometimes get to the 220F range.

Anyway, in the last 8 months or so, I've noticed normal driving temps anywhere from 205-210F, and up to 230+ when pulling my trailer. With temps getting warmer now, the engine temps are going up more. The engine runs fantastic except for a very slight, occassional miss at idle after it reaches operating temps. There is NO hydrocarbons in the coolant, NO oil in the coolant, NO loss of coolant, NO coolant in oil. It burns about 1/3 qt of oil about every 3,000 miles, but it's been doing that for several years. NO codes have shown up any scanners.

The plugs & COPS have about 10,000 miles on them. The radiator was replaced (upgraded to 4 core), along with a new water pump, and fan clutch less than 3,000 miles ago.

The truck did run hot about 6 yrs ago (bad water pump), but things were checked out afterwards and everything was fine......good compression, no fluid cross contamination, etc, and it has ran fine until about 8 months ago.

I'm having a hard time believing it's a head gasket, or cracked head, but I'm running out of possibilities, unless somebody here has any ideas. I TRULY hate the thought of changing the head gaskets in my driveway, money is tight, and everybody wants STUPID money to do the job.


EDIT.......Oh, I forgot to ask. Are the 5.4 SOHC heads from an f-150, 250, etc compatible with the Expy engine ? If push come to shove, could I put 99/2000 F150 complete 5.4 intro my 99 Expy ??
 

Hamfisted

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Yes they're compatible. All the way up to the '04 2V motors. What weight oil are you using now ? Warm summer temps and high mileage motor would be worth a 10w-40 synthetic just to be safe. You can run as cool as a 180 thermostat without triggering any "motor's running too cool" DTC codes. If you do swap heads or motors, stick with '99 or newer so you keep the PI heads.






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tekrsq

tekrsq

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THANKS !!!!!! I'm running 10w-30 dino oil. For whatever reason, it burns through synthetic oil almost as bad as gas. It does much better with old school dino oil.

Right now, I have put the 180 degree thermostat, but it's still running anywhere from 15 + degrees warmer than normal.

On a side note, does my description of the issue sound like a blown head gasket ? To me, it "does but it doesn't". I can't believe how well the truck still runs.....I'm having a hard believing it would still run this good, I'm just trying to make sure I have completely eliminated every other possibility because money is TIGHT, and I'm only going to be able to do this once. If I do the gaskets, then find out it's something else in the motor, I'm screwed because I won't have the money to "fix it again".

Also, anybody have recommendation for a quality reman engine ? I've seen quite few that are "affordable", but the companies have total shit reviews for quality warranty issues.
 

GlennSullivan

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You do state you are not losing coolant, there is no coolant in the oil or combustion byproducts in the coolant. That almost rules out all the cracked head / blown head gasket identifiers. Have you tried pressure testing the cooling system? That might shed some light as to what is going on.

I assumed you have observed the fan clutch assembly to confirm that is is operating correctly.

You mentioned 6 years ago you replaced the water pump, how many miles ago was that? Is it possible the impeller is bad or slipping on the pump shaft? Have you observed circulation (cap off or squeezed the rad hoses) when warm?
 
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tekrsq

tekrsq

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You do state you are not losing coolant, there is no coolant in the oil or combustion byproducts in the coolant. That almost rules out all the cracked head / blown head gasket identifiers. Have you tried pressure testing the cooling system? That might shed some light as to what is going on.

I assumed you have observed the fan clutch assembly to confirm that is is operating correctly.

You mentioned 6 years ago you replaced the water pump, how many miles ago was that? Is it possible the impeller is bad or slipping on the pump shaft? Have you observed circulation (cap off or squeezed the rad hoses) when warm?
That's what has me stumped and why I'm having a hard time believing its head related.

In my recent quest to find the issue, the water pump, fan clutch, radiator, and thermostat were replaced (within the last 3,000 miles). You cant see any coolant flow because there isnt a radiator cap, just the coolant tank. I've burped this thing 100 times, but the upper radiator hose still seems soft to me after it's at operating temps. I have not done a pressure test.

While driving, it'll "pick" whatever temp it's going to run at (at least 15+ over normal) and stay there unless I either come to a complete stop, or put a load on it. If I put a load on it (like accelerating or going up a hill) the temp will rise at least 5-10 degrees, but level back out at its precious temp once I'm "cruising ". Regardless of temp, if I come to a complete stop, the temps will fall to about the thermostat temp (180 in this case).
 

GlennSullivan

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While driving, it'll "pick" whatever temp it's going to run at (at least 15+ over normal) and stay there unless I either come to a complete stop, or put a load on it. If I put a load on it (like accelerating or going up a hill) the temp will rise at least 5-10 degrees, but level back out at its precious temp once I'm "cruising ". Regardless of temp, if I come to a complete stop, the temps will fall to about the thermostat temp (180 in this case).
At some point during your ownership did it operate "correctly". If so during that time, were your driving habits the same, I.E local temps, amount of load you put on it or towing you did with it? Did anything else change, either operationally or mechanically from when it operated correctly?

It seems like it is not able to handle any increased engine heat load, but once you take that away, it is able to provide cooling down to thermostat setting. Almost like it cant get enough flow through the engine block (or radiator) to carry the increased heat load away. Your mention of rad hose not feeling full or flowing may be key. Did you match up the water pump impellers to make sure they were the correct rotation and size?
 

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When was this new 4-core radiator put in ? Was this change in temp performance related ? It can be 4-core, but not flow very well and starve the motor of coolant volume. I wonder if a good ole stock single core would actually cool better. Just thinking out loud, since you say the hose is soft.
 
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tekrsq

tekrsq

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When was this new 4-core radiator put in ? Was this change in temp performance related ? It can be 4-core, but not flow very well and starve the motor of coolant volume. I wonder if a good ole stock single core would actually cool better. Just thinking out loud, since you say the hose is soft.
My issue started before the change. I was concerned about flow, that's why I went with the new/ bigger radiator, and other replacement parts.
 
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tekrsq

tekrsq

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At some point during your ownership did it operate "correctly". If so during that time, were your driving habits the same, I.E local temps, amount of load you put on it or towing you did with it? Did anything else change, either operationally or mechanically from when it operated correctly?

It seems like it is not able to handle any increased engine heat load, but once you take that away, it is able to provide cooling down to thermostat setting. Almost like it cant get enough flow through the engine block (or radiator) to carry the increased heat load away. Your mention of rad hose not feeling full or flowing may be key. Did you match up the water pump impellers to make sure they were the correct rotation and size?
I've owned the truck for about 8 yrs, and it operated correctly.........until recently. No changes in driving habit, etc. I do a fair amount of towing about 5,000 lbs with it, but I hadn't pulled anything for at least a month prior to this issue starting. Water pump and other parts (except for the radiator) are Motorcraft, and specified for this truck.
 

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How are you tracking coolant temps, do you have an aftermarket gauge and sender?

Are you getting any codes at all? Do you have an advanced scanner that will show all Ford specific codes rather than the basic codes?

I keep thinking not enough coolant flow between the engine and radiator. It is very unlikely, but is possible there is some kind of blockage somewhere in the cooling system, limiting flow.

Try running the truck at load (the point where you see higher temps) with both the front and rear heat set on on high temp and high fan and all windows open. This will essentially expand the size of your radiator. First take note if the both heaters are putting out very hot air, indicating good coolant flow and then if this helps control the engine temp. If you get a lot of hot air and it lowers engine temp, it would indicate not enough enough coolant flow moving through the primary flow circuit. If you don't get very hot air, that would indicate not enough coolant moving through the system at all.

Besides a cooling system pressure test, you can also do a static compression and leak down test to get a better feel for the status of the head gasket, head and block.
 
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