Engine/Transmission (1998.5 - 2002) KDP...Ow, my back hurts!

[tbrudder]

When I joined this forum, right after I bought my truck, the KDP was one of the first things that caught my eye. Naturally, with a name like 'Killer Dowel Pin', it's an issue that gets one's attention. But reading around in the archives, it seemed like it was just a 12V problem (at least predominantly), so my fears slept.



But last week, I noticed some oil spots on the ground. I think it was from the fuel dripping down where I'd opened the fuel drain earlier in the day, but it got me looking around. Good lord, there was a bunch of oil on the front/bottom of that engine! The KDP started coming back to mind. Some Simple Green took care of all that oil (looks like it was all from the breather), but I noticed what looked like a crack in the timing case, low behind the damper. Aaagh! After panic went its way, I noticed a similar mark on the driver's side--both just casting marks, and some research showed the case usually cracks behind the fan hub bracket, anyway.



All this was so unnerving, however, I decided I should take care of the Pin, just in case, so I ordered the tab kit from TST.



Started working on it late this morning. Their instructions (very good ones, for the most part) had me removing the fan and shroud at the same time, by unbolting the fan pulley bracket. Directions I'd found here said it was easier to knock the fan hub off first, so I tried that. For the life of me, I couldn't get the bloody nut off. Even with a drift punch and some good whacks with the hammer, I couldn't get it off. Couldn't keep the belt from slipping, even with increased tension.



So I ended up following the directions. That fan is bloody heavy! My back is quite angry with me, and I imagine it will be for a while.



But I digress. Anyway, I got the cover off to find the tab won't work--there's a boss around the pin. Can't really tell if it's the new design or not, but the pin's still seated. I did what the old Cummins memo I read recommended--use a punch in the bore to make a 'dent'/hardened area, and put Locktite around the pin face. Hopefully, if it's not the new design, that will secure it. At least I got the crank seal changed.



Got it all put back together (in the dark, and my flashlight died, too--had to hotwire a spare tractor light off one of the batteries so I could see), and the fan didn't get any lighter.



Seem to run okay, and I didn't have any parts left over at the end (don't you hate that ), but I have one concern. When I first put the fan back on, it would spin freely. When I was done buttoning everything up, there was definite resistance, as if the hub had engaged. Fan was running as soon as I started her up, too.



It was in the upper 60s/low 70s, and I didn't think the fan should be running right off.



Is this normal, or did I whack something I shouldn't have? Don't think I let any of the fluid leak out, so I can't think what else I could have done. Any ideas?



Oh, and all you guys that went before--thanks for all the tips and advice.



--Ty

 

[bmoeller]

Did the fan stay on even after driving down the road long enough to get the coolant up to temp? If it shut off after warming up, it should be fine. Normally, the fan will run for a short bit 'til the fan clutch warms up a bit and disengages.

 

[Ncostello]

The sure way to remove the fan nut is to use a 1-1/4 wrench and quickly rap toward the drivers side. The immediate impact will knock it loose every time. But I realize not everyone has a wrench that size.



There were actually 3 cases made. Non-bossed, Bossed, and improved bossed. The improved case's lip edge around the bore edge is so slight you might have had it and not noticed it. Its not obvious at all but can be felt with a hooked scratch awl.



Mine was the improved case but I went ahead and tapped it back 0. 005" (per the mic dial), punched a bur in the bore per Cummins and applied Green Loc-Tite too. I kinda felt obligated to do something since I took it all apart only to find I had the improved case.



I once had a thread somwhere around here talking about the boss bore cases. You'd have to have a s-bend tab to work on those.

 

[tbrudder]

Originally posted by bmoeller

Did the fan stay on even after driving down the road long enough to get the coolant up to temp? If it shut off after warming up, it should be fine. Normally, the fan will run for a short bit 'til the fan clutch warms up a bit and disengages.

Hmm... I thought it was supposed to work the other way--stays off until it warms up. At any rate, I didn't have a chance to drive it much--it was late when I finished. And this morning I dropped it off at the body shop to get the hood repainted (from that load of shingles bouncing off my truck )



If the fan stays engaged all the time, what's the problem--fan hub? Anything to do other than replacing it?

Originally posted by Ncostello

Mine was the improved case but I went ahead and tapped it back 0. 005" (per the mic dial), punched a bur in the bore per Cummins and applied Green Loc-Tite too. I kinda felt obligated to do something since I took it all apart only to find I had the improved case.

Same here--that was too much work to just put it back together (especially since I wasn't exactly sure I had the nifty case). And I guess a new crank seal is worth something, too...



I'll be getting a bigger wrench if I have to take that fan off again.



Thanks,

--Ty

 

[bmoeller]

Originally posted by tbrudder

Hmm... I thought it was supposed to work the other way--stays off until it warms up.

When cold, there should be enough drag to make it run for a short bit. The fan clutches are thermally actuated.

If the fan stays engaged all the time, what's the problem--fan hub? Anything to do other than replacing it?

Sounds like it needs to be replaced to me.



By the way, what all comes in the TST KDP kit? Doesn't say on their site. Tried e-mailing them since I haven't had a chance to call during business hours, but no responce. Thanks.

 

[lil red cummins]

hydraulic fan clutches can be strange. many will be engaged at engine startup regardless of temperature. they will normally disengage once the oil spins to the outside of the clutch housing after the first rev up. some never engage until they are needed. not sure why the difference.

also, when you remove these clutches, you should not lay them down on the front sensor coil. its not the end of the world or anything, it is just recommended to lean them up against something that keeps them in their original orientation. this helps keep the oil in the right place.

on my '04 i don't think i have ever heard it yet. then again it hasnt been above 45 degrees since i picked it up.



fwiw



jim

 

[tbrudder]

Okay, thanks guys.



I did keep it upright while it was out of the truck, and I don't think I dinged it on anything, so maybe it just needed to sling the oil out. Guess I'll find out when I get it back from the body shop tomorrow.



As far as the TST KDP kit, it's the same for the 12V and 24V. Comes with directions (color pictures, even), the tab, longer bolt, some red threadlocker, a replacement front crankshaft seal, and a tube of grey RTV--doesn't have a replacement timing cover gasket, but my truck didn't have one in the first place, so I just went with the RTV.



--Ty

 

[bmoeller]

Thanks, I thought so, wanted to make sure.