Coolant in fuel

[bearman]

so you think the mirror was the issue? why did you not go back to the original shop in the first place? Ill never understand why people have something fixed some where then there's a problem with the work and they go to another shop. again why didn't you go back to the shop who did the head in the first place?

Yella71, I have found everything from rags to tune-up equipment under the valve covers. Once found a putty knife between the blower and intercooler. On a 8v-92 ddc The complaint was a rattle at idle but not when at high rpms. I still have the scrapper in my box.

 

[Roger63]

So here is the new twist. I dropped the truck off at the original shop that installed the new head. They must verify that head is leaking coolant to warranty the head. After 3 attempts 1 I witnessed, no leaks were found. So the only thing I can do is run it till it either fails or it keeps going.

 

[yella71]

Of course they have to verify it for them selves....I agree with that. does the engine have a fuel cooler on it? did they flush and clean the cooling system the first time? How much fuel was found in the coolant? by you or the other shop? how did you find the fuel the second time? did the coolant overflow? Im curious as I have run into this on some ford trucks...found the issue doing PMs.

 

[Roger63]

I originally found the coolant in the water separator filter. I drain it daily, by process of illumination I started isolating possible origins of coolant. Cooling system was drained and flushed. The 2nd time coolant was found in the water separator again. At no time was fuel pushing into the coolant system which happens on Caterpillar when injector cups fail. It must be the difference in head design.

 

[yella71]

it must be on the return side so the pressure in the cooling system is higher than the fuel pressure....Im interested to find out what gives...what engine is this? You said you had it checked by another shop then you drove it back to the original repair shop. was there coolant in the separator after that ride?

 

[Roger63]

Cummins isx 15 also there is no fuel cooler which surprises me due to the fact that so much fuel flows through the head absorbing heat.

 

[Roger63]

I believe 1 of 2 things happened, either there was residual coolant left in the fuel tanks after new head was installed. Or the new head is leaking periodically due to heat expansion and or load on the motor.

 

[yella71]

good luck ....now I have something to research while I eat my lunch. Keep us updated. Fuel left in the tank is a good thought, do the tanks have a drain? There must have been a lot of coolant in them. worth a look

 

[bearman]

Don't forget that emissions bs they use the coolant to keep the fuel cool while being used for regens etc. Just be glad it's not a Volvo which by now you would be out of business.

 

[bearman]

Yes drains are there but system needs to be drained completely. Roger63 did you give the mirror back. Ask why you don't see a charge on your bill for system check and pressurized the coolant system when the first repair was done and did they charge you for new coolant.

 

[Roger63]

Don't forget that emissions bs they use the coolant to keep the fuel cool while being used for regens etc. Just be glad it's not a Volvo which by now you would be out of business.

Oh yeah to put this in mopar terms, I have spent enough money on the regen system the last 5 years to buy a survivor 70 hemi cuda,CASH

 

[Roger63]

Yes I gave the mirror back, as far as my bill goes there was a pressure check after new head was installed. And I requested new coolant because it hadn't been replaced in about 18 months it was due.

 

[yella71]

Roger, do you have fuel heaters that use engine coolant? If so they my be leaking....

 

[Roger63]

Roger, do you have fuel heaters that use engine coolant? If so they my be leaking....

I do that was the 1st thing I isolated.

 

[bearman]

I bet the mechanic was embarrassed over that deal. He will never do that again.

 

[Roger63]

I got my truck back yesterday and I left this morning to go pick up my load again. I drove approximately 470miles and hooked up to my trailer and the wif sensor activated again. I'm hoping it was residual coolant leftover. But I will check tanks in the morning and see if any is left. I don't think this nightmare is over,yet.

 

[bearman]

I'm hoping it's over.

 

[Roger63]

I'm hoping it's over.

Me to I have reached the end of my knowledge on these engines,or at least I think I have.

 

[bearman]

We never stop learning it's the cost of learning that kills us. I'm still trying to figure out where fuel and coolant can come together. If a cup not leaking then have you had the dozzier looked at that has coolant running thru it also and fuel to do that Regen crap. I'm reaching with that but stranger things have happened. Be safe on the road.

 

[Roger63]

We never stop learning it's the cost of learning that kills us. I'm still trying to figure out where fuel and coolant can come together. If a cup not leaking then have you had the dozzier looked at that has coolant running thru it also and fuel to do that Regen crap. I'm reaching with that but stranger things have happened. Be safe on the road.

You are correct, but on this engine the dozier has no fuel return line.