Last week my coolant was right where it should of been, ive never had a problem with coolant loss or anything like that, went on a trip to Albany and back, 600 miles, three hundred there, three hundred back, she ran like a top, almost 20 miles per gallon, everything was great. last night I started my truck and let it warm up and it came up to temperature fine, I got out on the road and it seemed fine, within a minute or two I noticed I did not have any heat, which right off the bat means somethings wrong with coolant flow, and the temperature gauge started creeping up. so I pulled right over and the reservoir was entirely empty. I popped the cap off which was pressurized but not any more then ordinary I felt. put more coolant in there but I only had a gallon which as we all know is not even close enough to fill that reservoir. eased it home, the temperature gauge stayed where it should but I still had no heat what so ever. I jumped in it this morning and got it back here to my shop, no evident coolant leaks on the ground but I'm about to do a pressure test to the coolant system. If an injector cup is cracked, which im pretty sure one is, what is going to happen when I fill the system back up with coolant and pressure test it? The oil is still beautifully golden from it's oil change a week or two ago. So do I just fill it back up and pressure test it? I doubt its the waterpump but maybe it could be. When I drove it to work today it took an extra 10 or 15 minutes of driving for it to even come off the bottom peg of the coolant gauge...I still think an injector cup is bad though...

 

The easiest symptom you will find is usually a thin black layer floating on the top of the coolant in the reservoir. This is fuel that has gotten mixed in due to a cracked cup.
I am sure there are others who have more info but that is the most common that i know of.

 

I'd have to say that's whats going on. I've got the truck inside now and there is a build up of blackish gunk near the cap of the reservoir. that's a telltale sign. Is there a write up on here of how to replace these cups? Thanks for your help! I greatly appreciate it.

 

PaysonPSD had a good writeup but Photobucket got stupid and blocked the images. I am sure there are others out there but here is the first one I found.
https://www.ford-trucks.com/forums/9...p-r-and-r.html

There are other links with info as well in the same thread.

 

Tugly has a thread. Not a straight out "how to" but lots of info

https://www.ford-trucks.com/forums/1...-stick-up.html

 

Thank you everybody very much. I'm going to print them off and read them tonight. I've got the otc5024 Navistar injector sleeve puller/installer ordered, new sleeves, the Loctite 620 and new injector o rings ordered, everything should be here by Friday, and I'll start the removal Friday night and have it finished this weekend sometime hopefully.

 

Once you have flushed and filled the cooling system after replacing the cups, a little trick I did for a buddy.... Regardless of how much clean fluid he ran through, there was still a bit of fuel showing up on top of the coolant in the reservoir. I just rolled up a paper towel and just touched the top of the fluid and the fuel soaked up quickly into the paper towel. You could actually see it being pulled towards it. Seems like it left the coolant behind and just pulled the fuel. Took a few sheets and a few minutes but eventually we got it all out and it never was an issue again.

 

A cracked cup will result in fuel in the coolant not a loss of coolant or no heat. When I had a cracked cup I found out by a overflowing coolant reservoir

 

Well, I had not checked the coolant in a week or so. And everything was fine till last night when I realized after a few miles that I had no heat and saw the temperature gauge rise and fall, rise and fall so I have no idea how fast I lost the coolant. The front of the engine is nice and clean and doesn't show any evidence of a bad waterpump but maybe? Should I just fill the system back up and pressurize it? Im just worried if it is a bad injector cup that the coolant will do more damage when I pressurize it. The oil looks great, I just changed it last week. The engine runs great, no skips or anything. it does seem to have a little bit more bluish smoke then usual but our fuel stations have been having fuel gelling issues due to our -40 degree temperatures we've had recently and they've been messing with our mixtures so I thought that was related..Maybe not though?

 

If you checked your coolant last week and it was fine, and this week it was empty, what would be your suspects if waterpump and injector cups were ruled out?

 

Are you sure the coolant is not leaking out of the weep hole on the water pump?

I had trouble diagnosing my water pump going bad because the weep hole is not capable of being viewed, just the coolant that is coming out of it.

 

I'm going to put fill it back up and pressurize the system and put it on the lift and see what I can see, i was initially worried about it but i need to get to the bottom of this and it's not too late to cancel my injector cup order and tool order

 

as somebody already said if the cups are cracked then you should have fuel in the coolant and a rising coolant level that has fuel in it bc fuel pressure is around 60+ psi. Coolant psi 14-16. 60+ psi wins. Is there any steam coming out of the tail pipe when shes good and hot. Check your pass side carpet or floor board to see if is wet. If it is wet then I would think heater core. also check pass side front fender area on the ground to see if there is a lot of water dripping there.

Just tryn to keep you from doing cups cause it ain't fun. Riffraff has a good post on cup R&R. Old green coolant was easy to spot. Ford gold not so much. like sous said check that weep hole when shes at full temp or full pressure during test. I prefer full temp since that seems to be when it happens. Also check oil cooler area.

How many miles between coolant fills?

 

Alrighty, I've got it inside and three gallons of coolant later have pressurized the system. it is holding rock steady at 16 psi. i see exactly what you guys mean about there should be more fuel in the coolant and it filling itself up rather then emptying itself. I'm going to hold off till i can confirm whats going on ofcourse. what about an oil cooler failure? what would i see with that? and that's why I'm on here trying to dish it out and i appreciate everything you guys are saying and asking. There is no coolant on the floor on the passenger side, there is no droplets of coolant anywhere underneath it. Maybe the waterpump is only leaking at operating temperature as stated above? I'm going to leave it pressurized over night in my shop till tomorrow and see if it holds and go from there. My oil is darker, it's also only 10 degrees here, i only ran it long enough to get it in my shop as i've let it sit since 8 this morning. but if three gallons of coolant was mixed into my oil, that should look like a tan sludgy milkshake and be so full it would almost be flowing out of my dipstick tube right? I'm trying to eliminate a bad headgasket too...i changed out the coolant and flushed it with ELC last year, she's been holding rock steady up till now, so for over a year now.

 

Your wife or coworkers messing with ya?