ISL 400 Leaking Pan Bolts

[wlf00]

I have a 2008 Winnebago Tour with a Cummins ISL 400 HP engine. During my last trip to Gaffney, I was told that I had a small leak around some (4 or 5) of the composite pan bolts. Some of the rubber washers are cracked and oil is seeping out around the bolts.

I checked with the local Tampa Cummins dealer and they would cover replacing them under warranty but their hours have changed. They are not open Saturdays and only open until 4:00 weekdays. Seeing that I still work full time, I have to waste a vacation day or two bringing the coach there and picking it back up.

Has anyone had this issue on their engine? I assume that I could just purchase the rubber washers from Cummins and replace those that are leaking myself. I would need to find out how much torque they should be tightened to when screwing the bolts back in.

Has anyone ordered parts from the Cummins factory? Or do I order them from the local dealer?

Thanks,

[Smitty77]

If it is minimal seeping, I would not worry about it while on vacation. Our ISL370 had several that also needed to be replaced when we purchased the coach, and was one of the items fixed at the owners costs based upon our agreement to purchase.

If it has evolved to a steady leak with ounces of dripping, then yes - take the time to get it fixed - but I doubt that is the case.

Interested in what others will post, as it is not an uncommon problem.

You could also make a call to Cummins, and if it is minimal seeping from your perspective, ask them to confirm you are good to go until after vacation.

Best of luck, have fun, be safe,
Smitty

[J Walker]

I would replace the washers myself and save a trip to the dealer. I doubt that the rubber washers are special and I would even try a generic one. On my ISB I found three pan bolts completely missing. They could have been that way from the factory but I believe they came out later. I removed another bolt and went to Home Depot to match it. I installed the new bolts and tightened them without a torque wrench. I do have a steel pan so my case is different. A composite pan would not present a problem. I would just watch the rubber washer to make sure it is compressed.

[JimM68]

Our local cummins dealer here has a very acxtive parts counter, they would sell you anything you need.

They also can deal with "drop-offs," where you can leave the coach the night before, drop the keys in a slot, and pick it up the next day.

They also run 2 shifts and are open from 7 am until midnight!
Maybe check further into what services they offer?

[wlf00]

Well here is an update.


I finally brought the coach in to the Tampa Cummins dealer. They did let me drop it off at night and drop the keys in their mailbox slot. I then picked it up at night by having it locked in their drive and used a second set of keys.


First off, the oil was not leaking because of the rubber washers on the pan bolts (they call them isolators). The threaded holes going up into the block are blind so even if the bolts were removed, there would be no oil leaking there. They put a dye in the oil to determine where it was leaking and determined that the pan gasket was the culprit. This then allowed the oil to seep down through the bolt hole in pan which in turn caused the rubber isolator to fail and crack.


To get the pan off, they had to remove the lower radiator hose, the oil pick-up tube, and the block stiffener plate. They then cleaned everything, replaced all of the parts along with new gaskets, and re-checked for leaks. All of this cost $695 in parts (32 isolator bolts at $11.70 each plus gaskets) and $535 in labor. Since the coach is in its fourth year of service and still covered under warranty, it only cost me a $100 deductible.


I am glad I brought it in.

[Gary RVRoamer]

My ISL 370 (same ISL 400 block) also has 3-4 pan bolts showing very minor seepage. I'm out of warranty, so not planning on any repairs unless it gets worse.

[EngineerMike]

Here's my $.02:
Seep: catches dust and makes a small leak apparent by visual inspection
Leak: wet, starting to drip, going to make a nasty mess as it gets worse and maybe ruin some wire loom, hose, etc.

When I find them, I wipe down seeps and note them for the watch list, and fix the leaks as soon as practical.

[Smitty77]

Bill - Thanks for closing the loop back on your results. Glad it was still covered, that always helps!

Gary - Our ISL370 (2004) had split isolaters when we were doing the PDI before buying this rig. Two years ago now. We had Cummins repair them, and the also pulled the valve cover to reset the Jake Brake when going into High (Cummins Cal Pacific, El Cajon, said some ISL370's left Cummins with the setting not at optimum for full high compression. As we test drove, we could detect no difference between low/high. They said the second bank of 3, were possibly helping 20% more the way the settings were. Not fulling closing of teh valve train as I understood it.)

After the work, we can now 'feel' the braking on high, though I admit and understand that the ISL just does not have the braking HP of the Big Block Cummins and Cat's - I do feel it, and do enjoy it going down the grades!

I have not had any more new oil leaking onto the isolaters, and will keep watching. The mechanic said it was not a critical problem, so I should not worry to much if it starts up again... As next time will be on my dime (doubt the 1st owner will be willing to pay for this one!) - I'll keep monitoring it and if does leak, wait until it is enough to be a PITA before repairing.

Best to all, be safe, have fun,
Smitty