I have a DD 8V92TA, (non DDEC) I started the engine today and within 30 seconds it just died. Never reached full idle RPM. Thought it may be a fuel problem so closed the ball valve just prior to primary filter. Replaced both primary and secondary fuel filters. Both had fuel when removed. I filled the new ones prior to replacing. I opened the ball valve and tried to start the beast. - No joy.
I suspect the fuel pump since it always looks 'nasty' around the pump like its leaking. Will try and prime tomorrow, and try a shot of starter spray in the air intake and see what happens.
While cranking, there is white-gray smoke that smells 'hot', but nothing. There is no air right now so emergency shut down is retracted. Could there be an electrical problem I have not checked or thought of. Coolant and oil levels are file, no indicator lights on dash, aside from no gen and low air.
If I replace the fuel pump, is it a LH or RH pump (I know stupid question), and should I replace the fuel lines while I am at it. Assuming Luke to be best source for the pump and lines?
Thank in advance,
Allan
1989 MCI 102C3 8V92TA with HT740
I'm not sure if this is your problem but check your rear start panel and make sure the switch didn't get moved to the off position. The engine will start with this switch in the off position and run until the air pressure comes up enough to actuate the shut down cylinder piston. Then will not run again until air pressure is lost. Don't ask me how I know but someone here helped me once with this.
John
That rear switch is so common, I think a lot of us flipped that switch in the beginning.
Don and Cary
I've been trying to start it from the rear box. So don't think its the problem, but thanks for the reply.
Allan
When I had my problem I started from the rear also. I didn't notice the other switch in the off position. I changed fuel filters and all before I was told about the switch. I was only hoping it would be this simple for you. The fuel pump thing would not be as easy or fun. Hope you can get it going with out to much time and problems.
Don and Cary
I had bus mechanic friend tell me stories about moving this switch and sitting back and laughing at the new drivers that couldn't figure it out. I don't suppose they made it easy on them either. LOL
John
If he's getting a lot of white smoke, he's getting unburnt fuel to the cylinders right?
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Is it shutting down because the shutdown cylinder is activating and closing the rack or is it just dying?
If you're starting from the rear, you can easily see the shutdown cylinder. You said it's retracted, but does it stay retracted?
Is the air pressure at zero, or is there some air in the system?
You need to determine HOW it's shutting down first. Then we'll focus on WHY.
It only shut down once, now it will not start. When it did try to run, 30 sec or so, no power, and did not reach full idle rpm based on my ear. I have no tach.
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You lost prime just prime it good it will go if doesn't pick up fuel after a couple of attempts it could be the fuel pump or drive
I'll try and prime today. Have never done it before. I have spin on filters. Working at my storage yard without to much support - whats the easiest way - being its a Sunday followed by a holiday. Was planning a trip next weekend, bummer....
Think I'll start the gen and the air compressor - put air in the bus and make sure the shut down solenoid is working properly - then prime and try again.
When you turn on and off the ignition from the back, you can watch the air cylinder on the governor releasing the off lever. Sounds to me like you don't have fuel pressure. Fuel injectors need over 20psi to operate properly. Even if they are getting some fuel (like getting white smoke), it won't be enough to fire off the motor. Probably your fuel pump-they are not that expensive. Good Luck, TomC
The easiest way is remove the plug from the primary filter and adapt a garden sprayer or a electric pump from Auto Zone or you can buy the manual priming pump off Ebay and pump a gal or 2 fuel through the system you don't lose the fuel it returns to the tank.
A dry 8v92 can be a bear to prime just filling the filters if the fuel pump is a little weak fwiw prime it good it will fire, the 92 will blow white or black when they lose prime depending on what mood they are in that day.
It's not the shut down if it was closed there would be no type smoke black or white
good luck
Make sure that your fuel shut-down air cylinder is working properly first of all. Most installations require air to shut down, therefore removing the air line to the cylinder should allow the governor to put the rack into the "full fuel" position to start. Just hate to see you get into deeper doo-doo tearing into the pump if not needed.
Good luck.
Ted.
Tom, assume the fuel pump is LH? Might go ahead and order one along with some new fuel lines. Looks like I'll need to drain coolant down so I can get the cross over pipe off.?
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All DD have LH fuel pumps the LH and RH are just to mark the suction,you shouldn't need to drain the coolant to replace the fuel pump unless at some time in it's life the crossover pipe was installed upside down.
Even with the crossover removed the 1 bolt is a bear you will need a 7/16 C wrench,I would not rush to change the pump just for a little seepage check it and be sure it's bad,prime the sucker when you get it running install a pressure gauge at the secondary filter if you have 50 to 70 lbs psi on the gauge the pump is good
A new pump cost is 150 bucks,rebuilt about 140 bucks but you get 60 bucks for the old pump so it ends up costing 80 bucks the seals are 5 bucks, check Luke but PC Industries and Diesel Pro are usually cheaper if you need a pump
Right now trying to get 5/16 hex fitting off the primary. Going to get one that I can get a bar on...
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Quote from: BeastMaster on May 24, 2015, 11:54:29 AM
Right now trying to get 5/16 hex fitting off the primary. Going to get one that I can get a bar on...
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usually, the fitting that you are after is the one in the front of the filter base, or the top......is that the one you are attacking... ???
(https://busconversionmagazine.com/forum/proxy.php?request=http%3A%2F%2Fcdn2.bigcommerce.com%2Fserver5400%2F14weq%2Fproducts%2F11386%2Fimages%2F14046%2FFB1301__29062.1410937660.106.106.jpg%3Fc%3D2&hash=a22746d5652e688d32a66e56b37ab355f20b469e)
Yes, it's a female hex, I guess 3/8. My allan wrench fits but no leverage
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Quote from: BeastMaster on May 24, 2015, 12:48:50 PM
Yes, it's a female hex, I guess 3/8. My allan wrench fits but no leverage
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normally there is a square head plug... i feel for you, someone put the hex on you >:(
Clifford, I thought White or Black smoke was " Is a Pope- Not a Pope"!.... ::)
Its a LH pump.
Check air to the engine. Sounds like you aren't getting enough air.
Gray-white smoke is usually an indication of unburned fuel.
Check your air before you before you replace anything.
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TomC touched on it if there is not enough fuel for a injector to preform the atomization process they puff out smoke,but he can check his muffler and air cleaner for birds nest
I'll check the muffler, but we were just out last weekend for the Virginia samboree. We take it out at least one weekend a month
This is the first time it would not fire. It's been dripping fuel more than oil, so leaning towards pump.
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Lol that is a good reason to looking at the pump if they leak that much the beast is going to lose prime
(Judging from the orginal post)
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Still can't get plug off prime filter plate, however ordered a new fuel pump and c wrench. Will keep you updated. Need it running by Jun 19, when we drive to Austin for grandson.
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You should replace the fork drive too look on the pump where the lines attach it will tell you if you need the RH or LH.
I always replace the pumps with a DDEC high capacity fuel pump a little more work but worth it IMO
"You should replace the fork drive too look on the pump where the lines attach it will tell you if you need the RH or LH.
I always replace the pumps with a DDEC high capacity fuel pump a little more work but worth it IMO"
Now I'm confused - I'm not DDEC concontrolled and not sure what a drive fork is. I'll try and attach a picture of the lines in - out of the pump.
Your fine just to keep the confusing down go back with what you have that is a 24-6 a good pump for the 8V92
The DDEC uses the same style only a higher volume.The fork will be on the pump when you remove the pump it drives the pumps and they wear the square will be come round over time, they don't cost much replace it for insurance those things are to hard to replace
I ordered a new LH drive for 8v92 and a c wrench, will it come with a new fork?
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No the fork is separate
Good news.... sort of, primed using the output of the pump through secondary and through the racks. Quickly reattached the line pump, the beast jumped to life. For about a minute or so then died. Confirms the pump. I was able to suck fuel from the in line through the primary so strongly believe it's the pump.
Need to wait for c wrench to try and get it off. Now need to find drive fork.
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You better check that is a RH pump in your photo easy to spot the difference the LH has the relief valve at about the 9 o'clock level the RH relief valve will be on the bottom
Please do post if the new pump install solves the issue. I know these pumps can go bad, but i guess there's a small part of me that wonders if this is something else...and not the pump. But I'm not experienced at all. So take that with a grain of salt.
It will not stay running until primed well. That pump will not pump air, as soon as it gets air you are done. One cheap way to prime is with a suction pump. They look like a grease gun. put a connection at the return line to the tank and suck fuel all the way through until there is no air left. You will need a cut off valve in the line to hold the fuel when you take the suction off. Most hardware stores have the suction pumps.
This did work for me over 10 years ago, but I still keep the pump in my coach.
Jack
I'll ask the dumb ?? Your bus isn't below 1/4 tank and sitting down slope on drivers side. Might not be picking up fuel from tank. Bob
Robert, it should have had enough fuel when I parked it last week end. It does slop down a little but leans towards passenger side. The pump has been leaking for sometime. I always dripped more fuel than oil! I was able to get it out of the bus yesterday, however still have not found a way to get the plugs out of the primary fuel filter for a priming pump. I never thought of the suction process on the return line. The tank is confusing however with aux tank, generator, and aqua-hot lines. If I pinch off the aqua-hot return line and use that fitting, could I pressurize the tank and push fuel through the fuel pump? I'll look at the parts manual and see if I can decode the return lines. Maybe money spent that I didn't need to, however, it the leak is stopped than the work was worth it.
Those plugs usually have Loctite applied a little heat they come out,not a big deal to install a tee and valve between the primary and secondary filter where it leaves the primary filter
Thanks. I'll fire up the heat gun tonight and try again. Thanks.
BTW, the lines into the pump came off easily.
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I don't think anybody has suggested this yet. The easiest way to prime any engine is to pressurize the fuel tank. It doesn't take much and you don't want to get carried away or you'll expand your fuel tank but all it takes is a couple of PSI to push fuel through to the engine. I use a circle cut out of an old inner tube and hold it around the filler neck with something - you can even hold it with your hand. Put air to it with a fitting cracked at the pump and keep pressure on until you have fuel flowing. Tighten everything up and it should start.
Hey Bob What's with you giving out Saskatchewan secrets LOL :) Crazy but sure works good.
What do you about the vents on the tanks ?, it won't work on a Eagle with the 2 tanks btdt
I second the "Pressurize the tank" method. But I have an actual nipple I can attach a garden sprayer to by the primary so I thankfully can prime that way and have done so many times. I have what appear to be leakage around my pump but I never lose prime from sitting. Ever. Coach sits a year and a half and still never loses prime. Only time I've lost prime was running it down too low on fuel. Anyway, I'm following this closely. My gut still thinks this might be something else....I'm probably wrong, but I'm watching the thread daily for updates.
I guess it depends where the vent is Clifford. I've never run into that. Not that I use this method daily but I've done it often enough to know it works. If the vent is via a vented cap then that's not in the picture when you pressurize through the fill tube but if there's a separate vent then it obviously wouldn't work.
Done it many times Bob it does work just not on vented tanks
Eight years ago I installed a 24 volt electric pump ahead of the primary filter with a bypass loop for use when not using the pump. I use it on annual fuel filter change, and one time when the engine lost prime while sitting in the shed. Otherwise, it's just cheap insurance and I never have starting issues after fuel filter changes.
Agreed that you're getting some, but not enough fuel. I assume cranking RPM is the same as usual and emergency flapper is not engaged.
Fred
Well the Beast is alive and well (at least I hope). Not sure what the final fix was. I replaced the fuel pump, the brass fittings going into the pump, installed a ball value and barb at the primary filter. Sorry for the delay but been busy - wanted to order new fittings going into the pump since the old one was a 90 degree elbow and the fuel line was running behind the water pump at a bad angle, in fact it appeared damage from previous install.
I added ten gallons to the tank, refilled all filters primed the pump using a small 12 volt pump. It really labored so not sure if that's normal or not, put a jumper between the start batteries and my house batteries to get a little more crank power. Turned on the main disconnect switch, turned on the main, walked to the back and hit the toggle. A little slow - but it jumped to life, ran it until full air and 140 temp. Shut down and cleaned up. Came back after dinner and started it from the front - just like normal. Not taking any chances next stop - fill it with diesel.
Still found it odd that I was able to run during the weekend outing, perform all my backing maneuvers to get it into storage, let it idle for a minute to let turbo cool, then shut it off. Came back in four days and it had lost prime.... Always a learning experience, I spent 40 years as an intelligence officer - working on small electronic things. As you can see it does not make me intelligent on big 8V92TA engines.
Thanks for all the help, suggestions and kind words. Without you guys, I would be dead and spending big $$ for someone to come out get it running.
Thanks again - Allan
Good news and thanks for reporting back. Something you did fixed it apparently. Glad she's running. A dead bus is kinda an awkward paperweight
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My guess is you ran it out of fuel. It happens to the best of us, especially on uneven ground. Heck, I even heard a story once about a guy who ran out of diesel a mile after filling up at a station in Nebraska with a pregnant wife, a tow car that wouldn't start and a bike on the back of the tow car that had a flat tire. No joke. Happened to someone I know whose first and last names are spelled exactly like mine.
Safe travels
RB
^ haha lol. That's a bad day. I honestly agree...how often do these pumps go bad?