Could it be the waterpump?

Fantom · Jun 15, 2012

Okay so I know I said I wasn't going to worry about it, but I'm a little concerned.

Just had new OEM oil cooler after having one put in last year along with a BPD EGR cooler, and still having super high oil temps 250*-ish I was already $2k into, still the same problem so I parked the truck after only putting about 50 miles on it.

Last month I took it in for ANOTHER OEM oil cooler, found out it needed HGs. So HGs, ARPs, OEM oil cooler, $4,700 I'm down the road.

Now with just about 200 miles on the truck since all the work, I'm seeing 220-ish EOT, ECT is usually 6-8* behind. Now I understand that it's hot out (96-98) and that affects it somewhat, but I saw this today

Now the coolant temp fluctuates but as many as 12*, the fan comes on if the ECT hits 220* and drops it back down to about 216*

The EOT does fluctuate, but only by 3 or 4* at best. I'm wondering if I might have a weak waterpump. Anyone else?

Fantom · Jun 15, 2012

Well damn, this was supposed to be in the 6.0 tech section, could a mod move it, please?

Nic · Jun 15, 2012

could be..mine with a 190 thermo runs 190-192 with the IAT at 90-100

Dave · Jun 16, 2012

Did you put a Tstat in it John?

Could be a water pump. But you usually see some leakage or hear some grinding before they go bad

Fantom · Jun 16, 2012

Yep, new tstat also. So that leaves me with what? Water pump, blockage in the radiator or....?

bismic · Jun 17, 2012

I assume that the coolant levels are good and no coolant loss? You can swap the coolant and oil temp sensors to see if one is biased.

Do you have a coolant filter? Do you see a good steady coolant stream in the return hoses to the degas bottle?

Did you flush w/ any chemicals on the last job you did w/ the coolers? In the past, did your coolant ever get diluted (perhaps running more on water than a coolant mix)? I ask becaise of possible corrosion issues.

I would also get a pressure gauge and watch the pressure in the degas bottle.

Fantom · Jun 17, 2012

Coolant levels are good and I'm not seeing any loss, the sensors are new. I do have a coolant filter, the coolant stream isn't steady, seems to lessen at 1800-2000 rpm.

I flushed it with restore and restore+ before the first oil cooler was put in and ran 20 gallons of distilled in it then topped off with 3.5 gallons of concentrated ELC.

I know the cap vents at 16 psi, what's the normal pressure range, if there is one?

fulton327 · Jun 17, 2012

I had a similar issue new oil cooler, headgaskets, and studs. With the stock turbo in the ect and eot were pretty close then I swapped to a bigger turbo and starting getting high eot temps. I assume the added power and the fact that ford decided to have a turbo that only has oil flowing through it which it has to absorb some of the heat on its way through the turbo. "why not have it water cooled as well " anyways. Knowing that my HG and oil cooler were good I put in a B&M aux oil cooler and dropped my eot by about 20-25 deg. I did a thread and put up pics in the 6.0 aftermarket section if you want to check it out.

Fantom · Jun 18, 2012

Right now, with the exception of the bulletproof EGR cooler and coolant filter, the truck is all stock. I'm not even running a tune yet. Hopefully I can get this sorted out soon, I've been waiting to get this sucker back so I could throw a FICM tune on it and injectors/turbo later this summer.

fulton327 · Jun 18, 2012

And you have a new oil cooler ? Since the eot and ect are both located on the oil cooler housing if they took it out they could have damaged the connectors or wiring, damaged the sensors or cleaned it with the sensors still installed. They dont like varsal or brake cleaner to much. I dont know the exact number but you should get a multi meter and read the resistance of the temp sensors or if you have the money just change them. It sounds like you have done everything else about all thats left is electric side of the system.

fulton327 · Jun 18, 2012

And on a side note just because a sensor is new doesnt always mean its good. Ever go to autozone and get a "brand new " alternator or starter that didnt work ?

Fantom · Jun 18, 2012

Yep, new oil cooler was installed when they did the studs and gaskets. The oil temp sensor is new, if I haven't mentioned that already. The temps climb while I'm cruising and come back down when idling. So Gene at BPD came tot he same conclusion that it's most likely the water pump. If the impeller is cracked when the rpms go up, the crack "opens" and the impeller doesn't spin on the shaft as it should, when I'm idling it's not spinning as fast so it works properly. Have a BPD water pump on the way, we'll see what happens.