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Author Topic: Clogged injectors?  (Read 3783 times)
scotty_vince
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« on: July 13, 2010, 04:29:09 PM »

Maiden voyage after five years of sitting, idled fine for the past few months I have been gutting and replacing interior. Today was first time for me to take her out on the "big road". Started right up idled great as usual. Took off down the small road pretty strong. Got to the medium road and started lugging up hill as we pumped a huge black cloud of smoke on to the people behind me. I then stopped and put 20 gallons in before hitting the highway just in case. Started to get on the highway and it just got worse from there. As I pushed the pedal down it just felt like a plane falling out of the sky. 5 miles later we were limping home with no power and plenty of black smoke. The filters look fine, she will start right up and idle, but as soon as you want really move it's like having only one cylinder. Please help being a newbe is nerve racking.
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James77MCI8
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« Reply #1 on: July 13, 2010, 05:06:43 PM »

What engine do you have?
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Chopper Scott
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« Reply #2 on: July 13, 2010, 05:21:54 PM »

Fuel filters probably. And at that you may need to drain the existing fuel and start over. And then you may need to change filters again until you get the old crap out of your tanks.
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robertglines1
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« Reply #3 on: July 13, 2010, 05:36:27 PM »

lack of air--clogged air filter----shutdown flapper mostly closed----reset energency shutdown damper--
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scotty_vince
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« Reply #4 on: July 13, 2010, 05:43:51 PM »

Yeah, sorry I forgot to mention what engine it was, that might be kinda helpful. It's a 6-71 Detroit in my 53 4104. As for the fuel issue I completely drained it and refilled with about 50 gallons. The filters were changed and I checked them after I got home and they seemed to be fine exept for a little crud where the intake to the primary is ( on top of the sock filter)
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robertglines1
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« Reply #5 on: July 13, 2010, 05:45:55 PM »

Did you change air filter????Black smoke is excessive fuel in the air fuel mix...easy fixs include  air filter or emergency shutdown damper tripped. then it gets expensive
« Last Edit: July 13, 2010, 05:54:12 PM by robertglines1 » Logged

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« Reply #6 on: July 13, 2010, 05:59:16 PM »

possible other causes: blower,Injector tips=it is basic in balance on fuel side and lack of enough air...
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« Reply #7 on: July 13, 2010, 09:38:39 PM »

I had my bus sitting for three years. I took her for a test drive around the block and hit it a little hard and could not see anything behind me because of the smoke. My smoke was white and it finally cleaned up after several miles of driving. I would have to say your issue is to rich of a mixture. Lack of air or injectors putting too much fuel in. I still have some white smoke on start up but goes away when warmed up. Hope you find an easy solution look for the obvious first like the nest in the aircleaner.

Good luck
John
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« Reply #8 on: July 13, 2010, 09:46:33 PM »

Maybe Dallas or Gus can help I believe the old GM buses have a washable filter before other filters


good luck
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« Reply #9 on: July 13, 2010, 11:57:04 PM »

Another Knut in a recent post, that is still warm, cleared this problem by resetting his "engine shut down" thing that is in front of the blower.  Emergency Shut Down!  They seem to leak enuf air to allow the engine to attain fast idle.

You do not have a plugged filter and a fuel starvation problem.


Do you have a "Filter Minder"?  That would have told you at a glance whether you had a plugged air filter.  Neat device and will save a ton by letting you use a filter as long as you can without "periodic replacement".  Also tells you to change the filter, regardless of it's age, if it is restrictive.  I installed one of those Permanent Oiled Foam" filters and it cut my MPG in half and I could see through holes in the thing that were unobstructed.  Pure trash..no redeeming virtue. $45 dollars down the drain.  Filter Minder installed!!!!!!  And right on the dash with a remote kit so I will always know the truth when asked.
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kyle4501
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« Reply #10 on: July 14, 2010, 05:26:14 AM »

My vote is restricted air, which should be easier to fix than faulty injectors.

Might have a nest in the air intake . . . . Mice can fit thru some small holes . . .
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« Reply #11 on: July 14, 2010, 05:59:02 AM »

Black smoke is incomplete combustion usually caused by not enough air getting into the engine. Check you air intake system for any restrictions/plugged air filter.  Jack
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scotty_vince
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« Reply #12 on: July 14, 2010, 08:24:14 AM »

I am going to check the air intake tonight after work. I will let you know if I find anything.
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James77MCI8
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« Reply #13 on: July 14, 2010, 09:20:58 AM »

I am voting restricted air flow.
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« Reply #14 on: July 14, 2010, 11:22:14 AM »

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« Last Edit: July 14, 2010, 06:24:49 PM by Now Just Dallas » Logged

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« Reply #15 on: July 14, 2010, 11:59:49 AM »

Check out your air filters carefully. On my 06 with the 8 cylinder engine it had 4 filter canisters. Also the plenum chamber itself
that connects them all together was almost completely plugged with nearly 40 years of crap. Usually have to take it down to get it cleaned out.    06 Bill
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scotty_vince
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« Reply #16 on: July 15, 2010, 02:54:58 PM »

So I took the plenum out. And it was completely clogged with greasy sand and dirt (felt and looked like clay). So I disassembled it, cleaned it, put back in. Started it up and took off down the road. Same symptoms, no power. Checked the intake pAssage ways, nothing found. I left and bought a can of "Sea FoAm". Put it in, lots of white smoke, took it for a ride....and it seams to be fixed. I'm not Quite sure whAt the problem was, but I guess it doesn't matter. Comments welcome. Thanks for the help.
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luvrbus
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« Reply #17 on: July 15, 2010, 03:10:36 PM »

You have a fuel supply problem your filters may look good but it does not take much to slow the flow get the fuel flowing the black smoke will go away and the power will increase. 

good luck
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scotty_vince
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« Reply #18 on: July 15, 2010, 03:29:12 PM »

Cool. I'm going to change them out tommorrow. Thanks.
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bevans6
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« Reply #19 on: July 16, 2010, 05:46:35 AM »

Where did you put the Seafoam?  I always though you put that into the carburetor?   

Brian
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scotty_vince
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« Reply #20 on: July 16, 2010, 09:12:22 AM »

I put it in the fuel tank.
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Chopper Scott
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« Reply #21 on: July 16, 2010, 10:38:36 AM »

Sea Foam is actually one of those snake oil products that really works.
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jaypullen
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« Reply #22 on: July 16, 2010, 05:38:48 PM »

What is seafoam and were can I get some Im having the same problem Black smoke loss of power and I checked the air intake (clear) and brand new air filters  I put this up a few weeks ago but still cant figure it out 1977 mci5 6v71 Any help is great Thanks JASON P
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« Reply #23 on: July 16, 2010, 06:04:48 PM »

Here is a link to the sea foam home page.  Tells you what it is, how it works, and has a link to find where you can buy it.


http://www.seafoamsales.com/


google is our friend you know

Mike

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« Reply #24 on: July 16, 2010, 06:05:51 PM »

Pardon my skepticism, but I truly do not believe that anything you put in your tank fixed the problem.
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« Reply #25 on: July 16, 2010, 06:25:16 PM »

I have to agree with Len, that stuff is like all the rest of the snake oil treatments, it does no harm, probably but it also does no good. Solvents mostly, which may knock loose some crud, something almost any diesel fuel treatment will do.

I looked at the web page, not a word about how it actually works. Many words about what it does though!!

If it is original you have three oil bath air filters above the engine. These can have varmint nests or be overfilled with oil.

The nature of the oil bath system involves the incoming air pulling oil from the bottom reservoirs up onto the side of the inner metal mesh filter. Too much oil will cut off the air.

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« Reply #26 on: July 16, 2010, 07:20:35 PM »

I really have to disagree. I have had great success with Seafoam in many different things and it seems to be a pretty good product. Granted it may have not magically cured this problem but then again it just did. I've had similar results with it. It's cheap, doesn't do any damage and I've read about it on many other forums from bikes to car buffs. Take my opinion for what it's worth.... 2 cents! Later
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robertglines1
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« Reply #27 on: July 16, 2010, 07:33:14 PM »

John Deer  dealer here told us to use it in  one of our mowers to help solve valve train problem...said try before tearing it down....very skeptical but about 40 hrs later that unit is running OK....don't think it will last but got more production out of it at a busy time of year...Sea Foam?snake oil?  positive outcome this time...still don't trust or understand
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« Reply #28 on: July 16, 2010, 08:00:23 PM »

At my Deere dealership my Parts Manager swore by Seafoam, and he sold a ton of it to customers!  I have a TDI Jetta with almost 300k on it.  One of the lifters was a little noisy on start up for about a minute.  He dumped half a can in the engine oil, I ran it for 5k miles, and the noise went away. It's been gone for 50k miles now.  I used it only that one time.  

Now, I've never tried it in diesel fuel, but if cleaned up that lifter, I would think it could clean up an injector, even if just a little bit!
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James77MCI8
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« Reply #29 on: July 17, 2010, 08:51:39 AM »

Old DD mechanic here swears by it. I have used it in many problem engines and it works.
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