Cat c9 coolant

spongebox1

Expert Expediter
Was wondering if anyone has ever had this problem, I have a 06 freighter with a c9 and my coolant has a sweet ureathane smell, I replaced heater core three months back, not overheating has good heat but it has this troubling odor, any help is appreciated,
 

runrunner

Veteran Expediter
Was wondering if anyone has ever had this problem, I have a 06 freighter with a c9 and my coolant has a sweet ureathane smell, I replaced heater core three months back, not overheating has good heat but it has this troubling odor, any help is appreciated,

I think coolant should have a sweet smell,could you be smelling a leak?
 

davekc

Senior Moderator
Staff member
Fleet Owner
Have the coolant tested for contaminants. If it has diesel in it, then it is a cracked/leaking injector sleeve.
 

spongebox1

Expert Expediter
Color has darkened a bit, no check engine light it smells like laqure or ureathene could be diesel I guess but its a very odd smell,
 

spongebox1

Expert Expediter
Will diesel in the coolant cause the hoses to deteriorate? Its almost like the coolant us seeping through the hoses, the heater core was plugged I replaced it and also replaced the hoses but the smell has come back, still got heat and not overheating or no check engine light
 

davekc

Senior Moderator
Staff member
Fleet Owner
When was the last time injectors were replaced? If it has been a while that is likely the cause. Fuel is leaking in through the sleeves. After injector replacement you will have to clean and flush the system. Use Cascade a couple of times and refill.

As a after thought, probably a good idea if it is diesel in the system, to change out all the injectors and the huey pump.
They are going to charge for a full injector change (minus the injectors) anyways because they have to pull them all since they won't know which one is leaking.
Not a place to go cheap.
 
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davekc

Senior Moderator
Staff member
Fleet Owner
You have to get the diesel out of the coolant system.
Drain, and replace with Cascade (dishwasher detergent) and water.
Flush twice with this and replace coolant.
Cascade is used because it is cheap and doesn't foam.
This is done AFTER you replace the sleeve that is leaking.
I would still test the coolant for confirmation.
 
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davekc

Senior Moderator
Staff member
Fleet Owner
It depends on what needs done. A flush, injectors, sleeves, and probably a heuy pump would be close to 4k. Depends on whether they replaced the pump. Highly recommended if it hasn't been done in a while. Take it to Cat rather than a dealer.
 

paullud

Veteran Expediter
I was thinking an injector cup, either way with a little homework it might be something to look into repairing yourself.
 

ttruck

Expert Expediter
Owner/Operator
had huey pump and injectors ,radiator, cooling system flushed along with fuel system flush 8k
 

spongebox1

Expert Expediter
Just pulled the maint records and found that all the injectors and huey pump replaced 14 months ago, they did not do a flush and did not replace the heater core, smell was evident before injectors were replaced, I just replaced the heater core and hoses a few months back, I'm going to replace the overflow tank and do the cascade flush and see if that cures smell, truck runs great but just want to be cautious, previous repairs were 7850.00 at a cat dealer
 

RETIDEPXE

Veteran Expediter
Lots of conclusions being jumped to. Here is my C-9 experience. I can turn a wrench but knew very little about diesels untill my adventure in expediting.

Coolant does have a sweet urethany smell to it. Was the heater core housing cleaned out when core replaced. If done at a dealer, probably just wiped it out with a dirty rag. Pull the cover below the right side dash and spray it full of dish washing soapy water, heater core and all, and rinse, it should drain out the condensation drain and you will now smell the flavor of dish washing soap you used. BTW, heater core replacement is not that hard for DIY'er.

My C9 inj sleeves started leaking at 723,000 miles. If you have an injector cup leaking, you will see the color of the coolant showing up in the fuel water seperator bowl as it does not mix with diesel. My Racor see thru bowl had red coolant Cat uses contrast well with the green diesel. Also, you will get diesel in the coolant, you can pull the recovery jug cap (careful when hot) and look for a milk shake sludge on the bottom side of the cap. U will also see some dribbles of diesel floating on top of the coolant. I then pulled the injectors and did a coolant system pressure test to verify sleeves and nothing more serious like a head gasket or cracked block or head. Sure enough, I could see one sleeve slowly dripping coolant into the injector housing. If your motor has never been over say 240 range temp, you probably do not have anything cracked.

I researched replacing injector cups online and found many Power STroke utube vids DIY'ers. I bought my injector sleeves and o-rings, went to Star Bolt and Screw in Little Rock and found a 1-14 Taper Tap that fit nicely into the sleeve, welded a bolt to the top, ground off some of the taper to keep it from bottoming out in the sleeve, bought a steering wheel puller and made a make shift sleeve puller for around $45 (Cat wanted $600 for a puller and I could not find any aftermarket). Pulled all six sleeves with my make shift puller (be sure and catch the metal filings from the tap so not to fall into the cylinders, I used one of those plastic push/ pull fasteners like is found in older auto door panel assemblies, some use a coin, and then vacuum out good.

None of the sleeves were cracked, but the leaking sleeve had obvious trash (black something) smeared against the o-ring, probably there from new, causing the o-ring to leak. All the sleeve's o-rings were becoming brittle which is understandable being located that close to the combustion chamber temps. To do this, you need to know how to pull your injectors, research as you need to drain fuel and oil from the rail first. You don't need expensive injector puller tools, I use a small 90 degree pry bar and socket for a stand to pry the out.

It did take several flushings to remove the amount of diesel that accumulated in the block, trans cooler and radiator, just keep flushing untill water is clear. I bought radiator flush for this, but I like the Cascade idea to save a little. I pulled the plug on each full tank and found no coolant in the bottom of the tanks.

A couple six packs later, back together, sobered up and running down the road now with 846,000 miles. Did not have to replace injectors or injector pump. I do, however, clean injector tips from time to time to unclog the nozzles.

If your truck is running good and not smoking horribly, injectors and huei pump are OK. The diesel in the coolant, and coolant in the diesel did not cause any performance issues. All of the coolant was apparently caught in the fuel water separator. You mentioned your truck is not getting hot and running good, I bet a dollar to a donut you have some injector sleeve o-rings that are toast.

Hope this helps.
 

spongebox1

Expert Expediter
My overflow jug is backing up, it has that diesel smell and my fuel consumption is through the roof, can the diesel back into the system into the coolant?
 

tenntrucker

Expert Expediter
My overflow jug is backing up, it has that diesel smell and my fuel consumption is through the roof, can the diesel back into the system into the coolant?

Injector sleeves are leaking, fuel system operations at higher pressure than coolant system. So when o ring on the sleeves starts to fail, you get fuel in the coolant.

Sent from my DROID X2 using Tapatalk 2
 
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