Skip to main content ↑ ↓
Topic: Cummins oil leak (Read 1120 times) previous topic - next topic
0 Members and 1 Guest are viewing this topic.

Cummins oil leak

Yahoo Message Number: 21483
Are any of you familiar with the amount of oil that is normal to drip from the blow-by tube?
I've noticed some little oil spots on the back of the coach after several hundred miles. The engine oil seems to be coming from the crank case vent tube that hangs down from the driver side of the engine.
The engine does not use oil. I haven't added oil since the last service about 6,000 miles ago.

I have around 55k miles on the Cummins 350 ISC.

It doesn't appear to be normal to me.

Any constructive comments?

Thanks,

Larry
Intrigue
10762

Re: Cummins oil leak

Reply #1 –
Yahoo Message Number: 21489
Larry

I have a 350 ISC. I had the old dip stick that melted.
Replaced it with the insulated model. Now if I fill the oil to the top of the full line it will blow out oil until it gets about 1/2 way between the full and add lines then stops. I think that if you put more oil in than the engine needs it will blow out the tube until it finds its own level your engine needs. I think the new dip stick calibration is 1/4-1/2 inch off for my engine and if I fill it all the way to the full line it is over filled. Just my idea no proof.
Calvin

99 intrigue
10811

--- LARRY A HANSON larryhanson01@...> wrote:

Quote
Are any of you familiar with the amount of oil that > is normal to drip from the blow-by tube? >

I've noticed some little oil spots on the back of > the coach after several hundred miles. The engine > oil seems to be coming from the crank case vent tube > that hangs down from the driver side of the engine.

The engine does not use oil. I haven't added oil > since the last service about 6,000 miles ago.

I have around 55k miles on the Cummins 350 ISC.

It doesn't appear to be normal to me.

Any constructive comments?

Thanks,

Larry
Intrigue
10762

Re: Cummins oil leak

Reply #2 –
Yahoo Message Number: 21497
I had the same problem except worse Larry.
Covered the back of the motorhome and all of the toad. Noticed it on a Friday and had to drive all weekend to get to a cummins on Monday.

They put on a newer and larger breather/filter and that stopped it.
They didn't know why it happened. They steam cleaned everything for us and the job was done under warranty with a $100.00 deductable.

Good luck
Andy

02 Allure 350 ISC

Quote from: LARRY A HANSON
>

Are any of you familiar with the amount of oil that is normal to
drip from the blow-by tube?

Re: Cummins oil leak

Reply #3 –
Yahoo Message Number: 21504
Larry,

I have the same problem with my 350 ISC and it was caused by over filling the pan at the last oil change. The oil level was over the high mark on the dipstick. I drained about one quart of oil from the pan so the level was below the high mark on the dipstick. That solved the problem for me. Hope this helps.

Jon

2004 Inspire #51008

Quote from: LARRY A HANSON
>

Are any of you familiar with the amount of oil that is normal to
drip from the blow-by tube?

Quote
>

I've noticed some little oil spots on the back of the coach after
several hundred miles. The engine oil seems to be coming from the crank case vent tube that hangs down from the driver side of the engine.

Quote
>

The engine does not use oil. I haven't added oil since the last
service about 6,000 miles ago.

Re: Cummins oil leak

Reply #4 –
Yahoo Message Number: 21505
I too had the "melted dip stick tube" problem. When the CC tech replaced mine at a recent rally he did two things; First he made certain that the new tube and new dip stick were the same lengths as the old. Secondly, he warned me that he was unable to slide the new tube onto the engine fitting as far as the old tube was on. He needed a heat gun to soften up the tube more to allow it to stretch on.
It is conceivable that you have the same problem.... i.e. your new dip stick is not going as far down into the pan as the old one (because the new tube is not fully seated). Therefore, when you fill the oil level to your "full" mark, you've put a little too much oil in.

Joe

2004 Allure '36 #31031

Quote from: cal harris\[br\
]

Re: Cummins oil leak

Reply #6 –
Yahoo Message Number: 21513
Larry,

My timing cover, on the front of the engine, started leaking near the balancer. It was just enough to make an oil spot on my pad and to get the rear of the coach and the front of my toad messy in about 1000 miles of driving. The shop that replaced the gasket told me that it is very common on Cummins ISB and ISC engines. You might take a close look there.
Mike

'95 Intrigue 10061

Quote from: LARRY A HANSON
>

Are any of you familiar with the amount of oil that is normal to
drip from the blow-by tube?

Quote
>

I've noticed some little oil spots on the back of the coach after
several hundred miles. The engine oil seems to be coming from the crank case vent tube that hangs down from the driver side of the engine.

Quote
>

The engine does not use oil. I haven't added oil since the last
service about 6,000 miles ago.

Re: Cummins oil leak

Reply #7 –
Yahoo Message Number: 21535
I mis-spoke.... I should have added that he also checked to see that the dip stick "full" level marking was the same. Something I think you would naturally do anyhow.

I disagree that the LENGTH of the tube is not the problem. Even if the replacement dipstick is marked at identical places as the original, the dip-stick tube MUST be both the same length, AS WELL AS seated on the engine fitting to the same position. If not, even the "correctly" marked dipstick will reach a different level in the oil pan.

Joe

04 Allure 36' #31031