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Message |
Robert V (70.16.62.197)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 17, 2004 - 7:10 am: | |
Yesterday I had an authorized DD Service Center (Penn Power) come to check an excessive cold smoking, oil box drain problem I was having with the 6v92 in my bus. I had tried everything that I was told to try before spending the money on a mechanic. Nothing seemed to help. Well, it appears that oil is getting into one of the cylinders on the right bank at an excessive rate.
I asked the mechanic why when the unit is warmed I doesn't really smoke, his answer was that the hotter the engine is, the more efficiently it will burn off the oil. He showed me, that on cold acceleration the engine has a distinct rattle/knock that he said is the unburnt oil throwing off the timing.
Well, I'm waiting for an estimate. Already been a day and haven't recieved a call. Must be a long list of figures.
I had just really starting to have fun with this project. Well guess this will just be a bump in the road.
One suggestion for anyone buying a diesel, make sure the engine is cold when you look at it. Found out that warm engines may not show all the problems....
Just a chance to vent...
Bob |
John that newguy (199.232.240.122)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 17, 2004 - 8:29 am: | |
I'm not a mechanic, but wouldn't sheer logic lead to this train of
thought?
Oil getting into a cylinder is going to be getting into that cylinder
at any temperature. Oil thins as it heats..... If the cylinder is burning
it, you would have a hell of a time trying to get it to idle, if you
could get it to idle at all....
I would get a second opinion before parting with the cash. |
TWO DOGS (63.156.216.13)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 17, 2004 - 9:06 am: | |
If your oil leval is going down...you are burning the wrong stuff..hate to say it,but sounds like it might be expencive..the roughest thing about this hobby is finding a GOOD 2-cycle mechanic that likes to work on them...and is good at it...we sure need a list ( ! ) of 2 cycle mechanics across the U.S....lots of diesel mechanics turn their nose up at two-cycles.. |
DON FAIRCHILD (64.32.245.178)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 17, 2004 - 6:29 pm: | |
Robert; where in penn are you. did the mechanic tell you where he thought the oil might be coming from. Does it have a miss when you first fire it up. do you start it up and let it idle for long periods of time with out driving it.
Don |
Robert V (12.152.140.209)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 18, 2004 - 3:44 pm: | |
Not in PA., the company who checked the engine is called Penn Power, they are in PA, NY and CT and do quite a bit of on road service. When I recieved the bus, it was driven 600 miles to here, after it arrived I checked the oil and added 6 quarts (Rotella T). I have only run the bus (at high idle) for about 50 minutes or so. After about 20 minutes I noticed oil coming out of the air box drain, which I emptied. After another 30 minutes of running, the air box drain was leaking and nearly full again. We have also noticed heavy (white/Blue) smoke condition when the engine is cold and warming. Added another 4 quarts of oil. There is a miss, which causes a thicker puff of smoke (when cold). Drove the bus for about 4 miles the other day, the smoke problem got 80 percent better. After it sat overnight and cooled, it was just as bad. The smoke will obscure the neighborhood. Penn Power told me that it was either oil getting into a cylinder from a ring problem on right side of the engine or possibly a blower to block gasket problem. Penn Power wants $8 - 10K for a rebuild, som I'm having someone else look at it... |
TWO DOGS (4.226.105.148)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 18, 2004 - 6:24 pm: | |
that's a little steep....look at "burning bus"...on the 'e' place.... |
Don Fairchild (64.32.245.178)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 18, 2004 - 8:39 pm: | |
Robert;It is probly a blower seal, an oil control ring will not usealy cause that much oil.
The other thing that will cause that much oil is a rist pin retainer and that won't clear up.
I am from cal and curently in philly working for the navy, converting a 12v71 natural to a twin turbo inter cooled engine. They are conducting emissions testing on the parts that we sell. I work for Clean Cam Technology Systems. cctskit.com
I am wanting to go up to ct to look at a bus and then on to main and do some flyfishing. if I can be of help let me know and I will see if I can work something out.
Don
Don |
Dallas Farnworth (172.128.127.50)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 18, 2004 - 8:54 pm: | |
RObert,
I know you have been asked this question before, BUT!, Are you running API CF-2 Oil?
I know that if I put even 1 gallon of 15-W40 into my crank, I'll throw oil that is almost unbelieveable.
When I run the straight 40wt CF-2 oil, oil consumption STOPS. |
Robert V (141.149.216.125)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 18, 2004 - 9:25 pm: | |
The wrist pin retainer was the other thing that was mentioned by the DD Tech. I'm still baffeled at the fact that the smoke will nearly totally clear when the engine is warm and worked. I understand that these 2 cycles can smoke some when cold, but can they efficiently burn oil when warmed up? Or am I being sold a bill of goods just to bring the bus in for a teardown.
Well anyways, found a long-time diesel man at one of the local trucking companies who has graciously offered to take a look and listen tommorrow. Apparently this guy is one of the best in the area. This bus just came off the line and had recently passed emissions test. Records show that it was losing about 1 quart of oil every 350 miles. This was a transit/shuttle, short run, so 350 miles could be a few days of solid running. The company that I bought the bus from (without warranty) has agreed to "make it right if there is a major problem". However, they will not pay for a rebuild. Their offer is for an exchange of a sister bus (I have the inside of this unit stripped out, so it would have to go back together)or ship a used engine. In either case I don't know what I'm getting. So at this point I'm continuing on my present path of researching the problem.
Bob |
Robert V (141.149.216.125)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 18, 2004 - 9:36 pm: | |
I forgot to mention, couldn't find 40wt, so I did add 15-40 Rotella T. The oil was changed before I got the bus, but don't know what they used. The other thing I didn't mention was when driving the bus under load I hear a loud hissing from the rear engine area, but it's hard to tell exactly what it is while driving, and it does make this hiss on high idle. It could be completely normal or would a bad blower/block seal cause hissing? |
TWO DOGS (4.227.117.72)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 18, 2004 - 10:12 pm: | |
I think you are going in the correct direction getting the expert 2 cycle guy....we sure need a list ( ! ) |
FAST FRED (4.245.230.83)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Thursday, August 19, 2004 - 5:23 am: | |
Try to change the oil for the correct oil BEFORE your expert looks at the coach.
I would sugest a long drive after oil change , so he can listen & look while warm,
And leaving the coach O'nite so he can see if its really a problem in the cool AM.
FAST FRED |
Rodger in WA (64.70.24.67)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 21, 2004 - 12:16 pm: | |
A novice's story and some comments on this subject:
Several years ago, after a long conversation with the seller, a converter, publisher and used bus dealer, I crossed the US to buy a bus in Long Beach, CA. I was a novice about buses and DD 2 strokes. The seller, purported the bus to be in excellent shape from bumper to bumper, "a turn key bus with a near new 8V92, ready for conversion".
Upon startup, the engine put out lots of white smoke and oil dripped steadily from the air box drains (slobber tubes). Oil was seeping from joints in the exhaust pipe leading to the turbo. I had an experienced DD 2 stroke mechanic check it out. He removed one air box cover and found oil. He deemed the engine "blown" and in need of an in frame overhaul. The seller offered to pay half on the overhaul up to $2500. The work to be done by a guy he knew who worked out of his pickup. That, plus many other things wrong with the bus convinced me to walk away from the deal.
Later, I bought a privately owned, professionally converted bus in IN with a 8V71N. It was obvious from the engine's appearance that it'd had a gone of miles since new or since its last overhaul. The owner had no record regarding the maintenance history of the bus or engine other than that it was converted for the previous owner who bought it from the Canadian govt. Started cold at about 40 deg ambient, the engine fired immediately and smoked hardly at all. It showed little evidence of leaks. I saw no evidence of oil dripping from the slobber tubes. A mechanic at nearby charter bus garage deemed the running gear, steering and suspension to be sound.
During the 1200 mile trip home to NC, via MO and the mountains of Eastern NC and towing my Honda Accord, The engine ran smoothly and strongly and consumed less than two qts of oil. The exhaust smoked hardly at all, except for some black puffs in the mtns until I learned to keep the rpms up and not "dog" it. The rear of the bus was still pretty clear of oil film on arrival. I had a local truck shop, that claimed to know 2 stroke DDs, go over the bus, replace all fluids, etc., replace a leaking parking brake popup valve and check out a wiring problem on the headlights. I told the mgr I wanted only DD approved 40W oil in the engine. Upon returning to pick up the bus, I found it idling while a mechanic worked on the headlight wiring problem. When I asked him why it was idling and for how long, he told me he was keeping the batteries charged while he worked on the lights. It had been idling at slow idle for over hour. There was oil pooling on the floor under the slobber tubes.
I discovered they'd put Rotella 15W40 (maybe 10W40)in the engine. I questioned the shop mgr about this. He said he had no 40W oil and insisted multi grade oil was fine. He also insisted that idling for long periods wouldn't harm a DD 2 stroke.
Leaving the shop, the bus produced a massive cloud of white smoke for the first 1/8 mile. Probably due the lengthy idling. Idle oil pressure, formerly 12 - 14 psi, was about 6 psi. After about 100 miles of driving, I found evidence of leaks where I'd seen none before, oil dripped from the air box drains and oil film and spots were accumulating on the rear bumper and eng. comp. doors. A check on the DD web site confimed what I'd been told about oil, namely that DD recomends only 40W oil in 2 strokes. I showed a print out of the DD info to the mgr and insisted he replace the 15W40 with 40W. He didn't have any 40W, so I brought him some. Upon replacing the multi grade oil with 40W, the drain tube drips, other leaks and the blue exhaust smoke stopped. Idle oil pressure went back to 12 - 14 psi.
My conclusion:
Oil in the air boxes and excessive white smoke is likely a symptom of excessive cylinder wear, bad piston rings or worse.
Multi grade oil in a DD 2 stroke, especially a worn one, will result in inceased leaks, higher consumption and lower oil pressure.
Idling for long periods with no load is bad for a DD 2 stroke. |
TWO DOGS (63.156.216.45)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 21, 2004 - 12:40 pm: | |
hmmmmmm......I thought the stuff coming out of the slobber tubes was fuel....I don't have the problem...but have heard it talked about here... |
Dallas (172.136.202.146)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Saturday, August 21, 2004 - 6:20 pm: | |
IId:
The stuff coming out of the slobber tubes is a mixture of oil and fuel plus lots of other junk.
The oil in it is being pushed past the blower seal.
My 4-71, when I got it as a brand new rebuild had 10W40 in it and passed it like eggs through a funnel or gas through a hen into the airbox.
My 6-71, blew oil all over the back end of my bus and little white VW.
Once I changed to the DDA recommended oil, almost all oil use stopped, and the little VW stays pretty close to white.
Again, for anyone interested, download DD's oil requirements:
http://www.detroitdiesel.com/public/technicianguides/technav.asp
If you don't understand what sulphated ash is, do a Google Search and learn.
The wrong oil will KILL your engine, not harm it, not make it dirty. It will KILL it.
Good Luck All!
Dallas
www.busconvertersguide.net |
huh? (66.167.95.178)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 22, 2004 - 1:53 am: | |
"gas through a hen" ??? |
John that newguy (199.232.244.239)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 22, 2004 - 7:39 am: | |
"Flatulance through a Fryer"
Maybe a 'lil mushed up...
"Well we shot that tunnel at a hundred-and-ten, like gas through a funnel and eggs through a hen"
--Wolf Creek Pass (Bill Fries, Chip Davis)
http://www.techren.net/mccall/works/wolfcreekpass/wolfcreekpass.shtml |
TWO DOGS (4.227.119.7)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 22, 2004 - 7:45 am: | |
just where is this farting chicken... |
Dallas (172.143.30.242)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 22, 2004 - 7:58 am: | |
Down at the Colonel's!...
OK, So I got it a little ackbasswards. Hehehe.
Just try getting a whole egg through one of those ittybitty funnels!
Instead of "Flatulence through a Fryer" how 'bout "Broiler Bubbles?" or "Pullet Puffs?" |
John that newguy (199.232.244.239)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 22, 2004 - 8:20 am: | |
HAHA. "Pullet Puffs" Yeah. |
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