if taking a "poll" on what cup/s have failed, would that help in the hypothesis?

 

A poll would be interesting. Gather data such as miles, driving style, chipped/unchipped, how many times the injectors have been out (if known) and if any re torquing has been done as preventative maintenance. I'd do it, but I'm limited to mobile for Now.

 

Oh and type of symptoms and type of failure.

 

I have been told after cup replacement it can take time for them to seat in.
In the meantime you have diesel fuel in the cooling system correct and what damage can this do. I seam to have a oil cooler leak now.

 

I had my cups, at least one, fail with less than 80K on my 2002. My mechanic replaced all of them and did a great job at a reasonable price. I do not beat my truck or haul crazy heavy loads with it. I pull a small camper and haul my trail Jeep around (not at the same time) and haul 3 tons of wood pellets once a year. No explanation as to why they cracked.

 

I haven't heard that. I didn't have any diesel in the coolant after doing all 8 cups. I did a complete flush and added all new coolant at the same time. I did have some oil residue show up from rushing the flush process, but no diesel.

 

Thanks guys.

Assuming it's thermal, a secondary question is, does the rate of temperature change have an effect (i.e. thermal shock), or is it just the overall change and the number of cycles? If thermal shock were a factor, using the block heater might help (personally, I do everything I can to baby my engine, including using the block heater more than most, probably).


I agree with this. They needed to use something that would yield to the iron head when being pressed in.

It certainly couldn't hurt. Although, while I don't know much about deep-draw forming, it seems they've got the process down, the cups I have seen seem to have a pretty uniform wall thickness. It would be interesting to slice a cup vertically and measure the wall thickness at various points, I'll bet it doesn't vary much.

How about a machined cup, instead of a drawn one? Might allow use of a better brass, or perhaps better control of the metal.

What changes do the forming processes impart on the metal itself (e.g. work hardening), and how can they be mitigated?

Could the drawn cups be annealed after drawing? Maybe they are.

I'm not a metallurgist, and don't profess to be, just tossing it out there...


That would be very interesting. As I said before, I'd put my money on "miles driven per day".


I wouldn't think so. Otherwise how would they handle it in a brand-new truck off of the line? Mine didn't leak at all, from what I can tell (on the second install, after I got it RIGHT)

 

I would also be very very interested in seeing a cross section of a cup! Someone like the thread originator that happens to have a few laying around should cut one up and post pics and take measurements.

Forming brass fatigues it badly and almost all the time if you look at any "formed" brass part under magnification you will see stress cracks. A machined cup would be ideal but time consuming and expensive.

 

I'd cut one up and measure it, but don't have a spare. I gave all mine to Christof to make shot glasses. Which reminds me I need to see how they turned out...

 

I can cross-section one later in the week or on the weekend. Unfortunately the ones I have are in another town, and I can't get to them right away. So, if someone beats me to it...

 

Now how the hell would I have room in my garage for a Superduty if I saved all the crap that I yanked out of it?

I'll try to remember where I put them... trash or otherwise.

 

Hmmm... I was t'inkin' when I put them away where I could find them for later review. I have an ideal situation here: I have the cracked one, a new one (the one I screwed up on), and I'll be in the shop today with tools at hand.

 

Dem sound like cuttin words!

 

LOL! I have my originals, and I have the new set that I screwed up, plus one that was damaged in shipment and replaced. Seventeen, total. Should make a nice set of wind chimes, or maybe one of those waterfall thingies to replace one of my downspouts.

 

If you replace the cups wrong and have diesel in the coolant can it cause the oil cooler seals to go out