| Author | Message | ||
| Dan Newport (Divemaster)
Registered Member Username: Divemaster Post Number: 1 Registered: 5-2008 Posted From: 131.137.245.197 Rating: N/A |
Afternoon busnuts This is my first inquiry into this group of crazy bus people...and i know it won't be my last..The last time this bus...4905 #404...was driven..i just bought it and drove it home about 25 miles..since then..i've been gutting it. Now...i want to start it and make sure all the wiring is in tact...but...with fully charged batteries...it turns over but won't catch. I've checked the air activated shut off lines...nothing in that area is out of the ordinary. The bus has sat for about 5 months...any suggestions would be greatly appreciated..thanks in advance. Dan | ||
| James Robinson (Jjrbus)
Registered Member Username: Jjrbus Post Number: 154 Registered: 12-2000 Posted From: 68.242.95.175 Rating: N/A |
Does it smoke when you try to start it??? If no smoke you have a fuel delivery problem. It may have lost its prime, fuel filters may be plugged, out of fuel. Could be bad check valve. welcome to the madness!! (Message edited by jjrbus on August 25, 2008) | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 810 Registered: 12-2000 Posted From: 76.3.173.51  Rating: N/A |
Welcome to the wonderful world of BusNuts. How fast is it spinning? Diesels have to spin FAST to fire off. If it is not spinning FAST, check batteries with a hydrometer or load tester (could have a bad battery). Check ALL battery cable connections (may have a loose and/or corroded connection). Check voltage at starter positive post, then spin starter and see how much voltage drops. Are you getting white smoke from the exhaust while it is spinning? If not, you are not getting fuel. Also check the emergency stop flapper in the air intake on top of the governor. Report back what you find. Jack | ||
| Keith Wood (Ft6)
Registered Member Username: Ft6 Post Number: 29 Registered: 8-2008 Posted From: 71.198.253.223 Rating: N/A |
If it's spinning at a good rate, check to see if the emergency shutdown solenoid is tripped. This is almost directly in front of you when you open the "hood," on the left side of the upper valve cover and looks like a can with a rod coming out of it, which operates a small catch. When the rod draws in (upward) the catch disengaged from releases a notched cylinder. There is a small stud on the cylinder, which you use to reset the system. If it's been sitting that long, you might also need to prime the fuel system. | ||
| RJ Long (Rjlong)
Registered Member Username: Rjlong Post Number: 1411 Registered: 12-2000 Posted From: 67.181.166.160  Rating: N/A |
Dan - Send me a private message with the complete VIN on your coach. I may have some very interesting information about it for you. . . Click on my name on the left to obtain contact info.  | ||
| Dan Newport (Divemaster)
Registered Member Username: Divemaster Post Number: 2 Registered: 5-2008 Posted From: 207.216.10.107 Rating: N/A |
RJ.. I tried to respond to your last...but couldn't get through...so i tried through my Hotmail acc't...that didn't work either..contact me through my own acc't....Danenewport@hotmail.com...once we've connected...i'll sendyou the VIN.. Thanks | ||
| Dan Newport (Divemaster)
Registered Member Username: Divemaster Post Number: 3 Registered: 5-2008 Posted From: 207.216.10.107 Rating: N/A |
Gentlemen.. Thanks for the help with your expertice...there is lots of fuel...i get white smoke...almost like a smog machine..the batteries are fully charged and the engine turns over very well..the emerg shut off trip valve is not tripped..i know where that is and it's in it's proper place..one piece of info...the previous owner ..who had it sit for over a year had to use lots of starting fluid to get it to fire..i know this isn't good for an engine..could it have damaged something inside?..thanks again for your interest.. Dan | ||
| David Lower (Dave_l)
Registered Member Username: Dave_l Post Number: 53 Registered: 11-2007 Posted From: 99.249.16.254  Rating: N/A |
How well did it start and run 5 months ago? It sounds like it is geting to much fuel, are the injectors dirty, is the engine compresion good. Dave L (Message edited by dave l on August 26, 2008) | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 447 Registered: 10-2006 Posted From: 208.100.193.210 Rating: N/A |
Needing starting fluid over 32F is a sign of very low compression. Could be broken rings from the ether , or simply rusty cylinders from not being stored properly. FF | ||
| Ednj (Ednj)
Registered Member Username: Ednj Post Number: 199 Registered: 3-2003 Posted From: 67.85.237.82  Rating: N/A |
Plug in the block heater for about 3 hours | ||
| Bob Shafer (Michigander_bob)
Registered Member Username: Michigander_bob Post Number: 56 Registered: 2-2005 Posted From: 24.11.11.204  Rating: N/A |
I have the exact same problem. When I first got the bus it started just fine. When I was in Florida last winter the starter took a crap and had it towed to Detriot Diesel and the mechanics just had to flip every switch on the rear panel. When I tried to leave it wouldn't start cause they closed the E/shutdown flap. Since then it just wont start without a shot of either, even when it's 80 degrees outside. Another thing it does that you might check is when it's at operating temp (180) and I shut the engine off, even for less than 5 mins, it it will start immediately then quit. It will do this 1 or 2 times. It has 158000 mi. and doesn't leak oil or burn it (1qt. /3000 mi.) I don't know much about DD but the first step should be to find someone that can help with a compression test. | ||
| Dan Newport (Divemaster)
Registered Member Username: Divemaster Post Number: 4 Registered: 5-2008 Posted From: 131.137.245.199 Rating: N/A |
morning.. Dave...5 months ago...it took a couple days of screwing around for this guy to get it to start..when i did start...and it was warmed up..it ran great...i let it sit over night..it would start right up... EDJN...i'll plug in the block heater and let you know..i have a 5 day long wknd coming up..this DD and i will get very close to all...again...thank you..i'll keep you posted..and i know a few people who work on DD's who might not have anything to do on a long wknd..lol Dan | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 812 Registered: 12-2000 Posted From: 76.3.173.51 Rating: N/A |
Dan, I would double check the emergency shutdown first, just to be sure. As far as starting immediately and dying when shut off less than 5 minutes before starting, this is what I found on my bus when it did that. MCIs have a low oil automatic shutdown. When the engine starts instantly and you release the starter button, you do not have oil pressure yet and the engine shuts down. after a couple time, there is enough oil pressure to keep the engine running. MCI added a pressure switch on the secondary fuel filter that is part of the start wiring. As soon as there is fuel pressure, it disconnects the starter, but over-rides the low oil shutdown. This does not happen on a cold start because you do not have enough air pressure to activate the engine stop cylinder. Check for a pressure switch on the secondary fuel filter. Then, next time you start the engine when it is hot and has air pressure, try holding the start button until you have oil pressure. Jack | ||
| niles steckbauer (Niles500)
Registered Member Username: Niles500 Post Number: 850 Registered: 11-2004 Posted From: 97.76.134.179 Rating: |
If the other suggestions don't work - "sitting for five months" Where? Check and see if something hasn't built a nest or died somewhere in your air intake system - FWIW | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 535 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
Dan, Lets look at everything posted here so far, and try to narrow it down a little. 1. Regardless of the make of the chassis, all buses of this vintage use air pressure to stop the engine. So, if you start your bus with no air pressure, then turn the master switch off, the engine will not stop. You will have to get about 80 psi showing on the brake reservoir gauge to get air thru the protection valve to operate the shutdown cylinder. 2. Jack has described MCI's low oil pressure shutdown, and the fuel pressure operated starter override. AS LONG AS THE BUS HAS AIR PRESSURE (see #1,) the engine will stop for either low oil pressure, or hot engine. When starting an MCI, the fuel pressure switch will disengage the starter as soon as the engine fires, but as long as the start button is held down, it overrides the low oil/hot eng shutdown, (see Bob's post above) if he held his start button down two or three seconds longer, his eng would continue to run when started warm. Actually that should be changed to "when started with air pressure," but anyhow... 3. Not owning a GM, I don't know how your start/low oil pressure override is done, but it doesn't matter, its there, or the engine will continue to run with the low oil pressure alarm on. When you try to start with no air pressure, the point is moot. 4. Don't want to pick on anyone, but you can't "flood" a diesel. Look at a "tractor pull," the smoke out of them is jet black under load, they are putting in ten times more fuel than the engine can burn, trying for more power. 5. What we need to know, was the overnight temperature. We all have great big cast iron blocks, (thermal mass) so if it got into the high 30s overnight, and stayed there for a while, then you came out at 9am at 50 degrees and tried to start, the block was still too cold. 6. Pull the air cleaner and look for a big blockage, as in field mice nests, or yellow jackets, etc. Look down the pipe to the flapper with a flashlight. Clean the air cleaner while you're at it, air's free! (I started this before Niles' post, and got wordy, so now there's two of us telling you to look in the air cleaner!) 7. I hope it hasn't sat for months on a less than full fuel tank, as in lots of condensation on the bottom? Now that you know what has to happen, lets do some more figuring. Lots of pure white smoke is probably fuel vapor, which means that none of it got to ignition temperature. Ignition temperature is acheived by compression, so not enough compression pressure=not enough temp, duh. Why not enough temp? Not enough temp to start with, (too darn cold outside for too long before) not enough compression pressure due to low cranking speed, loss of pressure by worn rings, or an intake restriction, (flapper or vermin.) Do us a favor, trip your flapper, and reset it, just to be sure. A second suggestion would be to set up for rear start, and hold the stop lever on the governor in the stop position when starting to crank for a few seconds. If no smoke appears, this rules out oil leaking around blower seals, valve stems, and rings, etc. Let go of the stop lever, and if white smoke appears, you have fuel being injected, just not enough temperature to ignite it, or the engine would or will start. A one or two second squirt of ether into the intake while cranking won't hurt anything. Just don't squirt a lot into any engine, especially those with glow plugs, before cranking. Whew, George (Message edited by George Mc6 on August 26, 2008) (Message edited by George Mc6 on August 26, 2008) | ||
| Laryn Christley (Barn_owl)
Registered Member Username: Barn_owl Post Number: 510 Registered: 10-2006 Posted From: 153.2.247.32  Rating: N/A |
I am one to disagree that starting fluid is the death of a two stroke. I have seen machines moved from one side of a lot to another with no damage from ether and the 71s were made to use it as a starting aid. If you have good compression and still need the starting fluid, you might have some sticking or dirty injectors. Injectors can malfunction and dribble the fuel instead of spraying it causing hard cold starts and poor fuel mileage. | ||
| David Lower (Dave_l)
Registered Member Username: Dave_l Post Number: 54 Registered: 11-2007 Posted From: 99.249.16.254 Rating: N/A |
I stoped by the DD dealer here in London to pick up an overhaul book and I ask'd the survice manager if he had any ideas about your problem, both he and a mechanic there said with out skiping a beat that there is a problem with the engines compression and sugested geting the compression check'd I guess I should have been more clear about geting to much fuel I was refering to the injectors beeing so dirty that the fuel is going in to the cylinders as a stream and not atomized that is what I was meaning by to much fuel or "flooded".It is up to you what you do to solve this problem by thinking about all the ideas given here.:-) Dave L | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 448 Registered: 10-2006 Posted From: 208.100.193.18 Rating: N/A |
IF you have to check the compression its as big long hour job , as the injectors have to be adjusted with a special measuring tool set and reset to work together (running the rack). This is an all day job , by someone that understands DD. My suggestion would to get a rebuilt set of injectors and IF the compression is high enough to not need a rebuild , install the injectors as its reassembled. FF | ||
| Luvrbus (Luvrbus)
Registered Member Username: Luvrbus Post Number: 527 Registered: 8-2006 Posted From: 74.32.86.19 Rating: N/A |
To add to FF the engine has to be running at 600rpm to check the compression not like most engines | ||
| Dan Newport (Divemaster)
Registered Member Username: Divemaster Post Number: 5 Registered: 5-2008 Posted From: 131.137.245.199 Rating: N/A |
Morning to all With reference to all of the above ..thank you..i'll be able to do some of the diagnostics myself this wknd...if the wife allows me the time..as for the new injectors...compression checks..at the moment..that'll have to wait till i know she'll run a little better so i don't have to tow it to the shop.I have a couple prospects about 5 - 7 minutes from my place so this will make it easier to get it checked out..to all..again..thank you and we'll yak more later.. Dan | ||
| David Lower (Dave_l)
Registered Member Username: Dave_l Post Number: 56 Registered: 11-2007 Posted From: 99.249.16.254 Rating: N/A |
Good Morning Dan I find your last post here puzzling at the begining you stated it would spin over but not start, now you say checking compression will have to "wait until you know it will run better", anyhow let us know how you make out what was the cause of this problem. Dave L Dan you can call P&R Western Trucks in Duncan they are listed on the DD web site as a DD service center. See if they will send a mechanic out to do a compresion check,they are 5 miles from Duncan (Message edited by dave l on August 27, 2008) | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1221 Registered: 5-2001 Posted From: 71.59.178.135 Rating: |
We have also found that elevation affects the temperature that will be needed to start the engine. With low atmospheric pressure, the peak temperature in the cylinder when cranking can be too low to ignite the fuel. For what it's worth. Tom Caffrey | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 449 Registered: 10-2006 Posted From: 208.100.193.121 Rating: N/A |
Personally I have never found an engine that didnt love a block heater, . Install a 1500W and see if she doesnt start easily. FF | ||
| Dan Newport (Divemaster)
Registered Member Username: Divemaster Post Number: 6 Registered: 5-2008 Posted From: 131.137.245.198 Rating: N/A |
FF...there is an inline block heater in already...so as of tomorrow night ...i'll be starting on it Saturday...it'll be plugged in... Tom..If i get any lower to sea level...i'll be a sub..I'm on Vancouver Island..elevation..about 75 feet..can't get any better than that without towing it to the beach..lol | ||
| Tom Caffrey (Pvcces)
Registered Member Username: Pvcces Post Number: 1222 Registered: 5-2001 Posted From: 209.52.177.221 Rating: N/A |
I agree, Dan. I mentioned it for two reasons. One, I didn't know what your elevation was. The other reason is that even though our coach starts right up with hardly any smoke, we spent a frosty night at about 2700 feet after several days of camping, and we got a surprise when I went to start it. With the engine right at freezing and at that altitude, it started about as hard as it did after an overnight in a rest stop at 13 degrees. It's something to consider when spending time at high elevation. For what it's worth. Tom Caffrey PD4106-2576 Suncatcher Ketchikan, Alaska | ||
| Dan Newport (Divemaster)
Registered Member Username: Divemaster Post Number: 7 Registered: 5-2008 Posted From: 207.216.10.107 Rating: N/A |
To all.. I'm the happy owner of a starting 4905 again...After charging up the batteries...and...plugging in the circulating block heater..plus a little 3 second shot of Quick Start...she fired right up and spewed smoke or a few seconds then settled down. My wife says i looked liked i'd found my long lost toy. While playing with a few switches..i found the A/C works great...blew crap and cruption from those air pipes that could have been there for a few years..all gauges work...once the air pressure was up...the air bags inflated and up she rose..i found the wiper switches...they work and so does the WWAF squirter..so i'm like a kid with a new toy...except that mine is 36 years old..you old guys...whats it like to have an affair with a younger 17 ton woman...lol.for those of you that gave me a quarters worth of opinions..and a couple bucks worth or experience..thank you..but...."I'll be back".. Dan | ||
| Jack Conrad (Jackconrad)
Registered Member Username: Jackconrad Post Number: 821 Registered: 12-2000 Posted From: 76.3.173.51 Rating: N/A |
Dan, Glad to hear all is well. Ain't it a GREAT feeling!!! If you have any other questions, ask away. All here enjoy helping and love to hear success stories. Jack |
