Used Cummins Diesel Questions

[Wilbur]

Thinking about buying an older motorhome (100K miles or less) with Cummins but not sure something(engine) won't be masked at purchase to be a problem after writing the check. Internet sites list a lot of things to look for, but want owner/operator feedback. Also, what is the average yearly cost of ENGINE maintenance when driving is 5-10K miles per year? I'm fairly good at working on gasoline engines but no experience with diesel. Any info will be appreciated!

[MrWizard]

i'm not sure the Ebay turbo for the Dodge version of the Cumins engine
would fit on the Cumins Factory engine intake and exhaust in an RV

these engines are built by dodge under license
NOT all of the 'bolt on' parts are the same

[tinkerer]

I once owned a motorhome with the famous 53 block that split from one end to the other. Would that hinder me from buying another motorhome with a Cummins? Not really as most of them are great engines.:)

[gutfelt]

Passin Thru wrote:
HUH? Turbos cost $287.00 on EBAY and you can put one in yourself in about 3 hours or have your neighborhood teenage mechanic do it. Just gotta penetrate oil the bolts first. You can even change bearings in one quite easily using Youtube.

you can buy a 425HP ISL cummins turbo on ebay for $287?? LOL

[Passin_Thru]

HUH? Turbos cost $287.00 on EBAY and you can put one in yourself in about 3 hours or have your neighborhood teenage mechanic do it. Just gotta penetrate oil the bolts first. You can even change bearings in one quite easily using Youtube.

[cwdavis]

Wilbur,

I'm coming late to your post, but with a point that hasn't yet been touched on, namely an important option for you if you get to the point of having the coach inspected. That is, like all the other engine manufacturers, Cummins has a network of service centers across the country, many of which are in a sub-net of 'Coach Care' Centers that also cater to RVers like us. I'd recommend strongly that if you have the coach inspected, you take it to one of these places to have the engine & chassis inspected.

We did this wnen we bought our coach, a 10 year old coach then with a 110,000 miles, a dozen or so years ago in Oregon, and since then the engine/chassis have performed flawlessly.

Cummins can't guarantee you won't have problems down the road, obviously, but they will at least be able to tell you whether there are any significant problems and the overall condition of things.

Overall, our costs have been directed much more toward the 'house' side of things (upgrading, mostly), than to the chassis & engine.

Best of luck!

[cvbdsl]

janstey58 wrote:
For those of you that put 4-5K miles a year on your Cummins DPs, do you change oil every 2-3 years, or annually? Does it hut a Diesel to sit over a winter with 4-5K miles on it when it can go 20K between oil changes? Thx, Jeff

OK I change the oil every year with around the same mileage as you are forecasting (I have around 55K miles on a used unit). It sits from around October to May over the winter (I do not start it or run the generator during this time) plugged into a 30 amp service and check the batteries on a regular basis (now). I also add an additive to keep the fuel from gelling in cold (up to -40 F/C the same at this point) in case I need to use it during the winter.

I don't think I need to change the oil this often but I bought an extended warranty and want to ensure that I comply with the recommended intervals in case something does go wrong.

HTH

Chris

[gutfelt]

gonesouth wrote:
When I bought my last diesel it was a 425 hp CAT the cat dealers recommended a cylinder cutout test......basically it gets the engine computer to run the engine on pairs of cylinders only by cutting off the fuel to the others, then a comparison of tach rpm to planned rpm gives a good test of how well those cylinders and injectors are performing. All in, IIRC it cost $250 and they claimed injection system and engine were in great shape. My experience showed that that was true.

the only engine related issue I had was the dash ac compressor seized hard and tore out the accessory belt. The belt was two weeks away and the ac compressor was four weeks away so we re-sheaved it and used a readily available belt to get it going the same day without the ac compressor.

there,s one nice thing about Cummins AC has a total separate compressor drive belt

I see your in NS friends just bought a place in PEI last summer man oh man are houses and propertys dirt cheap there

[gonesouth]

When I bought my last diesel it was a 425 hp CAT the cat dealers recommended a cylinder cutout test......basically it gets the engine computer to run the engine on pairs of cylinders only by cutting off the fuel to the others, then a comparison of tach rpm to planned rpm gives a good test of how well those cylinders and injectors are performing. All in, IIRC it cost $250 and they claimed injection system and engine were in great shape. My experience showed that that was true.

the only engine related issue I had was the dash ac compressor seized hard and tore out the accessory belt. The belt was two weeks away and the ac compressor was four weeks away so we re-sheaved it and used a readily available belt to get it going the same day without the ac compressor.

[janstey58]

gutfelt, I must drive more efficiently than you. I average 9.2 overall but on the flat easily get 10mpg. Cummins ISL9 is a great engine!

[Tom_Barb]

captnjack wrote:
Then why did you have to buy this belt?

Because I wanted the warm and fuzzy feeling,

[gutfelt]

MrWizard wrote:
1995 Safari, Cummins 6tb 5.9L
It's in my signature

I never said diesels weren't reliable
I said they cost like He*LL when something breaks

And it does

Apparently it just does it more often for me, than other DP owners

well in fairness to both side your unit is a pretty small old diesel pusher so iam sure repairs occur more often than the larger more
bullet proof system out there now and age things tend to wear out

[MrWizard]

1995 Safari, Cummins 6tb 5.9L
It's in my signature

I never said diesels weren't reliable
I said they cost like He*LL when something breaks

And it does

Apparently it just does it more often for me, than other DP owners

[gutfelt]

janstey58 wrote:
X2, plus you cant beat the CCC, towing capacity, Air suspension ride (versus the truck like bone shattering ride of my old gasser!) and quiet rear engine operation of the DP. I'll never go back! Plus I get 10mpg versus 6 in the former gasser.

10MPG?? with a 40+ ft diesel pusher man your one of one
Iam on my forth unit all the way from a mechanical isc 325HP up to a 425 ISL and they all got/get 7.5 MPG

[captnjack]

Tom/Barb wrote:

MrWizard wrote:
Cummins is reliable, until something fails
Then the diesel parts get expensive
Several grands for a turbo
More for an injection pump
The least expensive thing on this Cummins was the water pump $54 plus labor, it is an itty bitty thing, everything else cost out the wahzoo
Cummins is one of the best engines around, but those unexpected repairs can really dent the pocket book if they happen

Do you really believe the hoses, filters, oil, are any cheaper than the gas?
try buying parts for a V-10.
my life time serpentine belt for the cummins was 28 bucks, I'll never have to buy another.

buy smart not often.

Then why did you have to buy this belt?