| Author | Message | ||
| Scott Crosby (Scott_crosby)
Registered Member Username: Scott_crosby Post Number: 11 Registered: 12-2011 Posted From: 99.100.88.196 Rating: N/A |
Let me start by first saying that I know nothing about my bus. It seems to be OK we have only had it for less than two months and I drove it back from CA to IN over 2200 miles with no big issues and about 1000 miles since then. We are getting it in good working order, and have been doing little repairs to it that I have seen are issues. For example I replaced some cracked and leaking water hoses and in doing so noticed that both thermostats were stuck open so I cleaned the housings and replaced them with new ones. Flushed the coolant system and replaced the heat circulation pump motor and rebuilt the pump... I've been busy doing stuff like that. I changed the oil and filled with Delo 100 straight 40w, cleaned the air filters and baths, new fuel filters and oil filter, new airbags and air brake lines and cans, new tires, etc. Anyway just little maintenance stuff like that. Oh and I also added a 1500w block heater that heats and circulates coolant through the block. A little white smoke upon starting and after it idles and warms up it gives off a big cloud of darker smoke for about 2-3 seconds. If I let it idle for about 20-30 min it will give off one big cloud like in this video but then no real major amount of smoke. (disclaimer unless under a big load it will smoke like this, for example going up a mountain, holy dark grey smoke batman. I also saw a toll booth attendant totally disappear in my rear view mirror one time.. I felt so bad but yes I laughed when I saw it. The toll both was on a fairly steep grade and I gave it the full throttle to get up get going. Here is a video of a cold start and you can see the smoke. I know some people can tell some info about the condition of the engine from the smoke... what does this tell you? Injector problems? Engine problems? It starts so easy and just hums along when I'm driving it and no real smoke on start and stops or while driving around town once warmed up. This bus has like a million miles on it, I have no clue what's on the engine. I'm thinking about having the detroit torn down and rebuilt but if it's not necessary. Our plan is to have a really reliable bus to use. here is a link to the video. It's in HD and kinda big about 50mb. http://www.avonpicturethis.com/coldstart.m4v | ||
| Scott Crosby (Scott_crosby)
Registered Member Username: Scott_crosby Post Number: 12 Registered: 12-2011 Posted From: 99.100.88.196 Rating: N/A |
Oh and the big puddles under the bus are just snow melting off the top.... not a river of oil or coolant leaking out from under it. | ||
| Bill Gerrie (Bill_gerrie)
Registered Member Username: Bill_gerrie Post Number: 597 Registered: 3-2006 Posted From: 216.198.139.38  Rating: N/A |
Scott Smoke on cold start is normal. Because you stated the smoke is there when hot on acceleration and by the sound of the engine running you might be low on compression. To check that you can pull the air box covers off and see the top ring on the pistons. It is the compression ring. You should see a groove running around the middle of the ring if it is in good shape. Chances are the groove is worn off and this indicates worn compression rings. The air box covers are a metal plate with two small bolts holding it to the block. It is located on the side of the block next to the exhaust manifold. There are several air box plates under each maniflold. I hope you have the maintenance manual for the bus. It helps a great deal in repairing things. Bill | ||
| Scott Crosby (Scott_crosby)
Registered Member Username: Scott_crosby Post Number: 13 Registered: 12-2011 Posted From: 166.205.13.149 Rating: N/A |
Normal starts and stops and driving no smoke, just when on inclines or a steeper hill from a dead stop. I do have the manuals | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1867 Registered: 12-2000 Posted From: 98.242.20.32  Rating: |
Scott - Cold start white smoke with low outside ambient air temps are quite normal for a Detroit 2-stroke motor. With the block heater, try plugging it in for 2-3 hrs, then try a "cold start" - my guess is that you won't see as much smoke, if any. White smoke on startup is unburned fuel. Blue smoke is burning oil, and black smoke is too much fuel for amount of air available (over-fueling), most common when pulling a grade before downshifting. (Side Note: Too much black smoke pulling a grade w/o downshifting can quickly lead to overheating.) Best NOT to let the engine idle any longer than necessary. Get in, fire it up, build up the air pressure then GO! Diesels cool when they idle - to the point of lowering the combustion chamber temps sufficiently to create a lot of unburned fuel (and potential for washing the lubricating oil off the cylinder liners). If you must idle for any length of time, use the fast idle. Otherwise, shut it off. Along the same lines, better not to even start it up if you are not going to go somewhere. A cold start, extended idling ("to warm it up"), and then a shut down are VERY hard on just about ANY engine, not only the Detroit. And when you do go somewhere, drive it 20 - 50 miles or so to make sure everything warms up thoroughly and burns off any crud build-up. A good 100 mile run on the interstate at 55 -60 makes for a happy two-stroke!! FWIW & HTH. . .  | ||
| Bob Glines (Robertglines1)
Registered Member Username: Robertglines1 Post Number: 57 Registered: 11-2010 Posted From: 97.43.129.233 Rating: N/A |
While your pulling maintance. Ck air cleaner. Don't blow out if it has paper filter that will put holes in it. A partial clogged filter will make a diesel run rich. RJ is rite on with his advice. hardest thing you can do to it is let it idle. By the way I live at Evansville. Lots of bus guys up your way. Enjoy Bob | ||
| Bill Holstein (Billmoocow)
Registered Member Username: Billmoocow Post Number: 168 Registered: 5-2009 Posted From: 24.21.114.17  Rating: N/A |
If you're gona idle, treat it as your hot rod. Big motor, revs. Vroom Vroom! For long periods of time. You wouldn't let your weed eater idle! That two stroke wants to rev! | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1637 Registered: 10-2006 Posted From: 69.19.14.40  Rating: N/A |
If I let it idle for about 20-30 min WHY????? Its BAD BAD BAD! for your engine. RJ is right , start it , get air up and GO! Do drive modestly till the water is over 140F and no full throttle till 180F is reached. FF | ||
| Scott Crosby (Scott_crosby)
Registered Member Username: Scott_crosby Post Number: 14 Registered: 12-2011 Posted From: 99.100.88.196 Rating: N/A |
Well I was letting it get aired up and also the cabin heat warmed up, defroster working good and just warmed up enough to get the transmission fluid warmed up too. It was a city transit bus and I've seen them sitting around idling before runs and on cold mornings getting heat. But with this new info I will adjust my tactics. I don't have a temp gauges but maybe I'll add one. This is all new to me and pretty much opposite of how my brain says you take care of an engine... | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1870 Registered: 12-2000 Posted From: 98.242.20.32 Rating: N/A |
Scott - "It was a city transit bus and I've seen them sitting around idling before runs and on cold mornings getting heat." Yup, and that's why city buses rarely get more than 200K out of an engine, whereas Greyhound (and most charter outfits) will go 500K+ before overhauls. Also, 99% of all "city bus" operations nowadays are government-subsidized, thus utilizing your tax dollars to maintain equipment - a luxury you don't have. What your brain is used to is the fact that a gas engine will often overheat while idling, something we've all learned "as kids." Gotta change your mindset when it comes to diesels! People have often said that the best way to drive a Detroit 2-stroke is like you slammed your hand in a door - seems like the madder you are, the better the Detroit performs! FWIW & HTH. . . | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 1417 Registered: 11-2005 Posted From: 70.41.96.39  Rating: N/A |
If it doesn't have a fast idle switch you can add a hand throttle by attaching it to the foot throttle. As far as I know you can fast idle for a long time with no ill effects, but I stand to be corrected. | ||
| Scott Crosby (Scott_crosby)
Registered Member Username: Scott_crosby Post Number: 15 Registered: 12-2011 Posted From: 99.100.88.196 Rating: N/A |
It does not have a fast idle switch. If you could please explain more about what you are saying about how to add a throttle Gus that would be great. | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1640 Registered: 10-2006 Posted From: 69.19.14.26 Rating: N/A |
It was a city transit bus and I've seen them sitting around idling before runs and on cold mornings getting heat. 90% of the operating costs of most city buses are stolen , mis-directed from highway fuel tax. They hardly care about service life , less reliability is more MONEY! FF | ||
| Donnie Daugherty (Dr_detroit)
Registered Member Username: Dr_detroit Post Number: 29 Registered: 3-2008 Posted From: 98.145.193.107  Rating: N/A |
The fast idle switch on my old 4104 was a stick with a notch in the end. Cut to correct length,(some trial and error) then start up, press down on the go pedal and notch in place under the edge of the dash. Cheap, reliable, easy to replace and also doubles as a back scratcher. Your choice of wood, something exotic or plain oak, pine etc. Donnie Daugherty Enterprise Alabama PD4106-2772 | ||
| Scott Crosby (Scott_crosby)
Registered Member Username: Scott_crosby Post Number: 23 Registered: 12-2011 Posted From: 99.100.88.196  Rating: N/A |
Donnie did it double as your cruise control? Thanks for the high tech solution. I'm thinking antique prosthetic leg myself. | ||
| Sam Summers (Greyghost)
Registered Member Username: Greyghost Post Number: 122 Registered: 4-2011 Posted From: 166.182.3.224  Rating: N/A |
"Cheap, reliable, easy to replace and also doubles as a back scratcher. Your choice of wood, something exotic or plain oak, pine etc." Or a chittum tree branch, could triple the use... Sam Summers Enterprise, Oregon 4107 | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 1643 Registered: 10-2006 Posted From: 69.19.14.32 Rating: N/A |
Your choice of wood, something exotic or plain oak, pine etc." TEAK , for boat owners??? | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 2216 Registered: 10-2003 Posted From: 71.58.71.157  Rating: N/A |
Didn't work the greatest on our 4104; as engine warmed up, the idle would keep increasing, requiring resetting to keep it from running way too fast.King cruise control fixed that. | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 1418 Registered: 11-2005 Posted From: 70.41.96.39 Rating: N/A |
John is correct, as my 4104 warms up the idle speed increases with a fixed hand throttle. I always have to go back and ease it off a bit to keep it from getting too fast. I also use it as a cruise control. The hand throttle is original equipment for my 4104. For my 4107 I found a simple hand throttle at the HELP section of my local auto supply store and hooked it to the bottom of the air foot throttle. This one gets tighter when twisted so it makes a good cruise control as well. If you have a mechanical foot throttle you can also hook the hand throttle to it underneath the floorboard, depends on how things are arranged there. |
