"RMO" (aka wmo) and glow plugs, bad deal?
 

I have run "recycled" mo (sounds SOOO much better than waste[laugh]) in my cummins for a long time at 50%+ with NO ill effects, but it seems to not like my old 6.2 chevy very much. as a matter of fact, neither do I[duhhh] BUT has anyone had their glow plugs go bad sooner because of this?

They are the 12 volt plugs with a manual push button switch, held on for 20 sec or so.

From the reseach I did before I purchased a Cummins regarding WMO, is that you will need to clean your glow plugs more often due to the extra coking going on in the cylinders.

I'm assuming that once its running its fine, but its just trying to start it is the problem....Correct?

The other thing may be the 6.2's injection pump- I read somewhere that it has some sort of optic trigger that relies on light passing through the fuel, and the dark WMO interferes with it.

I'm pretty sure that only the GM 6.5 litre diesel has that optical sensor trigger thingy, the 6.2 doesnt.

IIRC the 6.2 has the old Stanadyne mechanical injection pump. The 6.5 had the electronic version.

I figure the WMO would wreck havoc with the glow plugs due to the fact the engine is an IDI, and the plugs crappy at best.

MikeyB

CORRECT!! sorry for not getting back to this; been off work so no 'puter time... The starting is the only issue; no power is the standard for this beast;) I already changed out the fuel filter, and it runs as well as it ever has(which aint that good), so I will pull the glow plugs and test them one at a time. Sounds like a GREAT way to spend the day...
Side note- do all 6.2 need the glow plugs to start, even when hot?

Not when hot, but they do even in 70 degree weather when the truck is cold..........

status? [coffee]

I got angry with the piece of junk when the $$$$$tarter took a dump and will be parting it out/scrapping it. YES, I do hold a grudge when it comes to 6.2 chevys:)
It has ALOT more issues, and is not really worth anything once I take the dump box, tires and batts out of it.

before anyone gets bent, I will give a rundown on the bad on this pos; starting from the grill- wiring has been butchered, ?glow plugs?, pump does strange things when running, engine was dropped at one point and starter bolt casting was broken off- starter held on by wire and one bolt, WILL NOT slip a tire with it's awesome torque unless on ice, torque converter shelled/replaced and I even got the BIG chunks out of the pan before I ran it again[nonono], body rusted out, rear springs broken, rear end has a hole wore thru the top:o, and bumper lost a battle with a kubota. there, I think I got most of the bad[coffee]

It does have a REALLY GOOOD HEATER tho!!!

sounds like a huckuva great deal

I used WMO in an IDI ferd for 6 years & the problem is that the glow plugs get a deposit of coke on them but if you pull the plugs every 4-6 months & take a wire brush to 'em they do OK.[coffee]

update on this- I sold it for $300, he took it home and got the wheels and tires back to me, then fixed the started solenoid and is pulling a side delivery rake with it!! I am not sad to see it gone...

One of the things you need to do to run RMO in glow plug motors is pull the plugs every 4-5K & wire brush the coke off so they start much easier.[duhhh]

Uh, that's not been my experience. I ran the stuff in my excavator, and yes, it coked up the glow plugs. It also coked up the precombustion chamber REALLY REALLY bad. Had to pull the injectors and scrape it out. To get it the rest of the way out I spun the motor while blowing compressed air into the injector port. I would guess there was about two or three heaping tablespoons of deposits per cylinder.

I know this was all new because I had relatively recently had the head off and replaced a bad valve and valve seat and cleaned everything up nicely.

The first symptom was a cooling system issue. It started getting hot, and struggling and smoking. Runs fine now, but I wouldn't put that stuff in anything. The efficiency I suspect I lost with the precombustion chamber filled up easily overcomes the "free" fuel.

My suspicion is that this particular coking is unlike wvo coking. Most automotive motor oil contains zinc oxide as a wear inhibitor (pretty awesome one, too) but it won't burn. That's what I think this stuff was.

I would not worry about the glow plugs. That's the least of your concern. If the precombustion chamber cokes up, the swirl pattern goes away, and your engine has less power, fuel efficiency and smokes more. Gotta pull the injectors to really get it out.

Supposedly direct injected engines are much less tolerant. Probably because there is less turbulence passing the injector tip.

Oh I DID burn a fair amount of the stuff before it became problematic. Maybe 40 gallons, which is a lot for a little 3 cylinder. It STUNK, too.