| Author | Message | ||
| Bob Damm
Rating: N/A |
1981 MC-9 8V71. I'm not a diesel mech. so forgive me if I don't use the $10 words  The engine has suddenly started using a lot of oil. It seems to start and drive normal, it's always been a smoker when first started. I have noticed that a more than normal (I would think) amount of oil seems to be dripping from the two vent tubes (more from the drivers side tube)on either side of the engine. Just where do these tubes come from (the crankcase)? And what is the likely cause? | ||
| John MC9 Rating: N/A |
What oil are you using, will be the first question on the list that will follow. "Delo 100, 40wt" is the answer you'll hear most. If you're using any other grade/type of oil, especially a multi-grade, then change it to the aforementioned, refill with the proper oil and run it hard for a few hours of driving. Then..... see if you still have problems... | ||
| morgan Clough (Mclough777)
Rating: N/A |
where do yall find delo 100? i can only find delo 400 40 wt. | ||
| John MC9 Rating: N/A |
The local bus garage had it. They said most auto parts stores can order it for me (or you)..? | ||
| morgan Clough (Mclough777)
Rating: N/A |
hmmm, i looked at NAPA online and not listed . oh well ill keep lookin | ||
| RJ Long (Rjlong)
Rating: N/A |
Morgan (and others) - The subject of oil and where to find it comes up over and over again on this and other bus message boards. The answer is simple: Go to the website of the oil manufacturer, and use the "dealer" or "distributor" locator found on the site to find someone close to you. Chevron, Shell, Mobil, etc., all have them, just takes a little web surfin'. . . Per Detroit specs, you need straight 40wt, API class CF-2 oil with 1% or less sulfated ash content. Most of the websites will also have the MSDS specs for their oil available, with a little digging around on the site. The MSDS sheets are where you'll find the sulfated ash content listed. Buy your oil at least by the case, usually six jugs of a gallon each per case. Takes seven gallons for an oil & filter change on a Detroit two-stroke, so you might as well order and buy at least two cases. You can also get it in five-gallon pails or 55-gallon drums. Your choose! Oh, and FYI, Chevron has changed the formulation for Delo 400, and the new stuff is no longer classified as CF-2. Check your stock! HTH, RJ PD4106-2784 Fresno CA | ||
| John MC9 Rating: N/A |
Also, to add - For whatever it's worth: http://www.steinoil.com/oil1.htm http://www.tejascoach.com/tejasoil.html#Oilrec Ask at your local Walmart also. Some stores are willing to "special order" various items for their customers! | ||
| David Dulmage (Daved)
Rating: N/A |
Its possible that the intake blower seals are leaking. Extended idling, particularly at low idle can also result in excessive dripping from the drain tubes. Keeping the oil level too high in the oil pan seems to affect oil consumption as well. As for Chevron Delo 100, 40wt vs. other oils, it's essential that a single weight oil meeting API Classification CF-2 is used, but there are a number of brands of oil that meet these requirements. Use of mult-grade and other oils not meeting API CF-2 and DD specs will greatly increasue consumption. The Detroit Diesel website has all the specifics for lubricating oil in a downloadable manual. I buy my oil from a local distributor and carry at least one case of it with me at all times, since it can be difficult to find a source while on the road. Dave Dulmage | ||
| Marc Bourget Rating: N/A |
Another resource re oil specs is MCI (taken from their monthly subscribed e-mail notice: "Proper use of engine oils and lubricants can make a big difference in how long your coach will last. And with so many to choose from, it's especially important to select the right ones. For a run-down on which oils and lubricants go with which MCI engines and transmissions, and how to conduct a proper pre-start inspection, click on http://www.mcicoach.com/fyiFromMci/maintMatters/0106.htm." | ||
| Marc Bourget Rating: N/A |
Posted the link before reading - here's the text of my message to MCI after realizing they didn't address 2 stroke models. Text follows: There are all to many MCI 7-9's with DD 2 Stroke engines used in charter and other operations not to include a reference to those oils on the link you provided in this month's subscribed e-mail! Is this a hint that you no longer support those MCI models? Marc Bourget Stockton, California" | ||
| Bob Damm Rating: N/A |
I have been using Delo 100 40w cf-2. I generally run it on fast idle once the air pressure is high enough. A couple of mech. said it's either the blower or bad rings. Since it started all of a sudden I would suspect the blower unless some rings broke. When my church first bought this bus from a company with a good reputation for servicing their buses I noticed that the dipstick showed it was overfilled by about a gallon. When I had a local shop service it I noticed it was again about one gallon over the full mark. The service tag said they put eight gallons in it. RJ long said it takes seven gallons to fill it? I've been wondering if I had the wrong dipstick in it but maybe the shops have been overfilling it? Either way somethings not right because the oil wasn't even on the stick when I checked it and it wasn't driven that far. | ||
| Dale Waller (Happycampersrus)
Rating: N/A |
Hey Bob, Pull the intake top off of the blower and see if the rotors and the inside of the blower has oil all over the place. You should be able to see if the blower seals are leaking without removing the blower that way. Has anyone ever shut it down with the emergency stop (flap)?? That can ruin blower seals quickly. Dale | ||
| Bob Damm Rating: N/A |
The emergency stop has not been used as far as I know. There is another driver but if he used it I should have been told, especially since he probably doesn't know how to reset it and I would have gotten a phone call. The coach may not belong to me, but it's still "my baby" and I like to know how everything works even if I don't have to fix it myself. | ||
| John MC9 Rating: N/A |
Hmm.. "Either way somethings not right because the oil wasn't even on the stick when I checked it and it wasn't driven that far." Bob.. this is going to sound like a foolish question, but.... Are you checking the oil before the bus has been run, or some time (within hours?) after it's been run? I'm wondering if the oil isn't draining down into the pan as quick as it should, and adding to it at that time is bringing it well over-full. | ||
| T. (Bluegrass)
Rating: N/A |
Tha book says that you should wait 20 minutes before you check the oil. I usually wait a couple of hours before I even look at mine. Tony | ||
| FAST FRED Rating: N/A |
"When my church first bought this bus from a company with a good reputation for servicing their buses I noticed that the dipstick showed it was overfilled by about a gallon. When I had a local shop service it I noticed it was again about one gallon over the full mark. The service tag said they put eight gallons in it. RJ long said it takes seven gallons to fill it? I've been wondering if I had the wrong dipstick in it but maybe the shops have been overfilling it? " "Tha book says that you should wait 20 minutes before you check the oil." Da Book I have sez to check the oil ON shutdown. When this is done and the oil is topped off , the result is it will read almost 1 gal high after a few hours. Really full oil might cause an extra bit of oil out the back. Too LITTLE can cause a trip to the DD fellows for a set of bearings , if your lucky , an engine if your not. You choose,your way, FAST FRED | ||
| Chuck Lott (Chuckmc8)
Rating: N/A |
I usually get blasted for such as this.....and... I'm not saying anyone else is wrong. The reader should consider all options and then decide for themselves. We're big folks-So, here is what I have researched and believe to be correct. The resting oil level in a cold engine should be 1" lower than the "lip" on the oil pan where it bolts to the block. Remove and wipe the oil dipstick, then put it back in and out, then note the level on the stick. Then replace the stick OUTSIDE and BESIDE the tube, so that you can see where the oil level is in relation to the desired full level, 1"below the pan flange. This way you can also tell if your dipstick is correct for your engine. My MCI operators manual says wait 3 minutes after shutting off engine to check the oil.I beleive this to be incorrect. The DD book says either 20 or 30 minutes. The best way to check it and be correct is while the engine is cold, with the coach sitting level. Da book cautions about having oil level in the pan too high and contacting the rear seal, when sitting. It also makes sense that the oil level, if up to the flange gasket would also be too full. If DD wanted a different level in the engine,such as starting it up, letting it warm up and immediately shutting it down, then checking oil, it would have been a simple matter for them to do it that way once, then, mark it on the dipstick so that it could be checked cold. Then,with a cold engine, check it and compare the level by holding the dipstick beside the tube and seewhere your oil level in the engine is at. Check it any way you wish-decide yourself which is 'right' for you. I'm not trying to convince anyone that I am right, only relaying what I beleive to be correct. Happy busin! Chuck Lott,Douglasville Ga. | ||
| John MC9 Rating: N/A |
"When this is done and the oil is topped off , the result is it will read almost 1 gal high after a few hours. Really full oil might cause an extra bit of oil out the back. Too LITTLE can cause a trip to the DD fellows for a set of bearings , if your lucky , an engine if your not. "(FF) "The DD book says either 20 or 30 minutes. The best way to check it and be correct is while the engine is cold, with the coach sitting level. Da book cautions about having oil level in the pan too high and contacting the rear seal, when sitting. It also makes sense that the oil level, if up to the flange gasket would also be too full."(Chuck) I also noted that the DD manual reads that way, Fred. Overfilling is worse than a few quarts too low. The DD will burn and lose oil over the duration of a trip. Running with less than a full crankcase is fairly normal for at least part of the trip. Over filling by a "gallon" can cause all sorts of problems, no matter if it's a DD or a car engine. | ||
| Marc Bourget Rating: N/A |
Only if the oil level is high enough to bring it in contact with the crank throws. I don't know that much about oil/crank contact in DD 2 strokes, but my 8V92 block is sitting on a flat surface with the crank installed. Doesn't appear that the Crank extends below the block's skirt. 1" below the pan/block parting line would appear to be 1" low. Assuming 12" wide by 30" long (guessimate) 1" equals 1.55 gal. volumne. Onward and Upward | ||
| John MC9 Rating: N/A |
Not just with crank throws. Once running over full (especially a gallon over), there can be problems of oil expansion and it being forced into areas it shouldn't be forced into, such as the crankcase venting system. There will likely be increased crankcase pressure as well... More problems in the making I doubt running a DD few quarts low is going to cause any problem at all, but running it over full by a few quarts, could lead to some real headaches. I check mine prior to any trip. It's part of every pre-trip check that I know of... | ||
| Marc Bourget Rating: N/A |
John said (in relevant part): "Forced into areas is shouldn't be forced into." I'm puzzled by this. Oil control is a big thing in race car engines, something about which I have a some exposure. [None of my experience tranfers over to R/C racers so I make no comment about them!) Lateral G's are the biggest problem. Assuming enough supply to the oil pickup, too much Oil supply to the rest of the engine never appeared to be much of a problem. Getting the the oil back to the pan for the pump was the bugaboo. Lateral G's "trapped" the oil up in the engine, dropping the level in the pan and, in some cases, starving the pump. I don't see our busses developing enough lateral G's to develop this problem. What am I missing here? If the supply in the pan is sufficient, the pump curve will be at optimum. How will an extra inch in the pan "force (oil) into areas it shouldn't be forced into? If the max pressure is exceeded the bypass kicks in, but the engine will always get sufficient supply in this scenario. Like more info on your point. | ||
| John MC9 Rating: N/A |
Not a rise in oil pressure, Marc... A rise in the air pressure within the crankcase cavity if it's a gallon (or more) over-full, and possibly greater still, as the oil expands. There's the complaint of: "oil seems to be dripping from the two vent tubes" and a question regarding where the vent tubes are connected. I'm still at the on-ramp of the learning curve with DDs, but.... if an automobile engine's crankcase is overfilled, the PCV valves will become clogged fairly fast. Too much crankcase pressure can pop seals... higher crankcase pressure and a too full crankcase, and oil can be forced into passageways that are intended for crankcase venting, not oil purging. It sure sounds like that may be happening here. Correct the errors of my assumptions, I have an *open mind. *(hole in head) | ||
| Tom Caffrey (Pvcces)
Rating: N/A |
John, I have seen plenty of clogged pcv while working as a gas engine mechanic. I have only seen them in cars that get short runs combined with cooler or cold weather. It occurs faster with a worn engine. I don't know if the auto type was ever used in diesels because they required manifold vacuum to do their job. Only some old Mercedes that used a pneumatic governor would have enough vaccum, as far as I know. I've never seen a car that puts in its time on the highways suffering from this. The clogging material appears to be a form of condensate from blowby, together with bit of oil, creating a kind of tarry substance. When I drove a Volkswagon out of Alaska in the early 70s in during the winter, I saw temperatures down to -60. While in Whitehorse, I looked in the filler tube and found it clear full of white foam from the moisture in blowby condensing in the pipe. When I got into the Seattle area, there wasn't a trace of the foam anywhere to be seen in that tube because the engine had finally warmed up and evaporated the water and combustion products. There was an interesting side note to the cold driving experience. Full sized pickup owners were complaining of only getting 4 mpg with $2 gallon Canadian fuel and the Volkswagon pulled off 24 mpg, while driving hundreds of miles in third gear because it didn't have enough power to stay in high gear. At -40, I could keep it in high gear. At -60, I had to drive it over 5 miles to get it warm enough to get it into third. That was some trip! For what it's worth. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| Marc Bourget Rating: N/A |
John, What's the cause of increased pressure in the crankcase as it relates to lower oil levels. I think I'm walking further and further into the woods here! LOL!! Marc | ||
| John MC9 Rating: N/A |
Marc - Re: "What's the cause of increased pressure in the crankcase as it relates to lower oil levels. I think I'm walking further and further into the woods here! " Deep, very, very deep into the forest, Marc!! It would relate to higher oil levels, not lower. Tom - "The clogging material appears to be a form of condensate from blow-by, together with bit of oil, --- because the engine had finally warmed up and evaporated the water" With a too full crankcase, the amount of heat to dissipate the water would be lessened. It would take more heat to dissipate the water than if the proper amount of oil were used, for the amount of heat expected (per engineered design). (trying to equate here, the crankcase over-fill , to the problems presented) (whew) | ||
| Marc Bourget Rating: N/A |
Excuse the inaccurate question, why does higher oil levels lead to increased pressure in the crankcase? JTNG said, as to water evaporation: "the amount of heat to dissipate the water would be lessened." Are you saying too much oil drops engine temp sufficient to block the evaporation of water? My understanding from posts by FF, DML and others is, except in Northern US during winter, etc., when the DD's don't get warm enough, would be a "too full" crankcase would only take a slightly longer time to come to temperature. The radiator thermostats will, for the most part, control engine temperature. The partial pressure of H2O at 160 deg and above is easily enough to drive off moisture. Oil is used for engine cooling but the cooling system, via the heat exchanger, is used to cool the oil (in addition to heat dissipated through the block). Gosh, I am further into the woods and the birds have been eating my bread crumbs. Help! | ||
| John MC9 Rating: N/A |
Dunno, Marc... "a "too full" crankcase would only take a slightly longer time to come to temperature" Would I sound like a former President, if I said that it depends on the meaning of "slightly"? I didn't intend to get into areas I have absolutely no expertise with, but I do believe what we've all learned through the years, regarding every gas or diesel engine: If you overfill the crankcase, you will cause damage to the engine, whereas running slightly low will usually not be harmful. From DD: "NOTE: Do not fill beyond the maximum fill level on the dipstick, since overfilling may result in high oil consumption." The "do not overfill" is stated numerous times throughout that document. The DD PDF file is *here*. Come'on out of the woods, Marc. Walk towards the light! | ||
| Richard Bowyer (Drivingmisslazy)
Rating: N/A |
I always found that my DD would throw out the first gallon if I filled to the full mark on the dip stick. After that it would stay about the same for a couple of thousand miles. Richard | ||
| Dale Waller (Happycampersrus)
Rating: N/A |
Wonder why Detroit Diesel didn't just make a dip stick that had the marks for FULL COLD and FULL HOT or AFTER RUN?? LOL. | ||
| Marc Bourget Rating: N/A |
Dale, +Maybe too many pan styles due to the great variations between vehicles and stationary installations. John TNG, Thanks for clarifying your earlier statement. I popped out the other side of that forest! BTW, referencing my contact with MCI, they sent me an e-mail that said if you have a question about the 7-9 series with DD 2 Strokes, just call. Makes me wonder if they don't want to add these engines to their current resources but will help you "offline" where they ain't so visible. | ||
| John MC9 Rating: N/A |
Prolly don't want to get caught up with pollution headaches. It may be legally safer to discontinue the production and support. |