Isc 350 leaking fuel

[cat938g]

I have an isc350 on a spartan mm chassis. I have a fuel leak dripping
down on to the starter. Cant get in any further to see where it is coming
from.. came home from a 350 mile jaunt, filled it with fuel. First time I have filled it full. It had not leaked prior.
Also while I was under the rig noticed a threaded hole in the flywheel
housing with no plug???????? Should it be that way? (on the bottom of the housing)
Any help would be appreciated.

[Perry White]

Plug should be out. So if you get a trans seal or rear main leaking

[mahon1993]

Sounds like a leaking fuel filter. On mine the fuel filter is right above the starter. Could be loose or the drain on the bottom of the filter is leaking.
Greg

[HeapBigEngin]

If it's a leaking filter, you are in luck for sure. In recent years, however, Cummins ISC's (maybe others too) have become rather notorius for leaking lift pumps. Seems that the new low sulpher fuel dries out the internal gaskets and seals....hence the leak. The pump is located right above the starter area....that's where I would look if the filter is tight. I had to have mine replaced since Cummins no longer offers a seal replacement kit for these. The other fuel leak issue that seems to occur on the ISC is a leaking fuel injector line at the fuel pump...ususally #5 or #6. Had that experience as well. Probably a lift pump, though....retails for about $275-$300. Labor about 1-2 hours with an experienced hand on the wrenches. Very tight quarters to get at the thing.

Please let us all know what you find out....Thanks!!

[GaryKD]

Hi cat938g,
There is a recall for certain ISC engines about a fuel leak in the high pressure line running to the injectors. It is on the passenger side of a DP, up near the top of the engine. One can see it by removing the hatch in the rear of the coach and looking at the engine from the top.

This photo shows the fuel line before the recall. Cummins Before Campaign 0805 Fuel Line + Bracket - iRV2.com RV Photo Gallery

This photo shows the fuel line after the recall.
Cummins After Campaign 0805 Fuel Line + Bracket - iRV2.com RV Photo Gallery

There are two rubber hoses. Look straight down between the rubber hoses to see the old and new fuel line and bracket.

[nplenzick]

I had the same problem this fall, brought to the truck repair center that I use and they found that the lift pump was loose. Tighten it and haven't had a problem yet with it.

[slickest1]

I had a fuel leak on my ISC 350 that leaked down on the starter. It was a line on the back of the injector pump. It was a return line so it was not high pressure. When I replaced it I tightened some of the other lines that were starting to leak. I think there was a recall on these lines but I don't think mine was covered. I read that this is a common problem on ISC's.

[Jimwo]

My 2001 ISC 330 was starting to leak and I found the 3 bolts that hold the housing together loose. I tightened them up about 1/4 turn each and no more leaks.

[cat938g]

I want to thank everyone for your replies. I have not found the problem but am working with the Spartan Cummins tech.... and will start this weekend! I will let you know what I find.....

[Bago40]

I just noticed the same leak. Took it in to the local Fort Myers Cummins shop and will see what happens Monday when they can get to it.

Mine leaked when cold then healed itself when the engine was warm while at the shop. The Cummins service writer said that the lift pump only runs 2 minutes then the engine's suction fuel pump takes over.

[cat938g]

Let me know if you will Bill. Mine is scheduled for the shop on Thursday next week

[Bago40]

Quote:

Originally Posted by cat938g Let me know if you will Bill. Mine is scheduled for the shop on Thursday next week

The coach is back. The lift pump replaced. Total cost $792. Good Sams Extended Warranty picked up $503 and I paid $288. I have $250 deductible policy and they don't pick up things like extra port plugs and shop supplies. The service manager said that this is a common problem with the ISC engine. The labor charge was more than the parts cost.

[cat938g]

Thanks for the reply Bill. Mine is in the shop today and I suspect the same problem.
I will let all know what happens.

[cat938g]

M isc350 was in fact the lift pump. The original has been superceded 2 times
by Cummins. Supposed to take care of future problems?.total bill with fuel
filter change $745.00 (out of my pocket)