So this has been going on for a while. I start it up and it will sound like it's down a cylinder or 2 or 3, I shut it off right away, then refire, it will either startup fine this second time or we do it one more time. I know it's running right when there is no smoke from the exhaust, even when cold it doesn't really smoke. Power seems good, she'll run past 80 if I let her.
https://youtu.be/thVBVz3KUd0 (https://youtu.be/thVBVz3KUd0) Here is a video from today showing how it acts at around 70 degrees.
https://www.youtube.com/watch?v=FHqbLanmH3I (https://www.youtube.com/watch?v=FHqbLanmH3I) This video here had lead me to believe this might be injector and or rack related.
Last year it did this as well, but I didn't know it was an issue. https://youtu.be/saUhVEeB8oA (https://youtu.be/saUhVEeB8oA) Being newbie bus owner, just figured it was cold. It does would work itself out on it's own, but shutting it off and refiring seems to be faster, and unburnt diesel washing down the walls is not good.
You most likely have a couple of injector that bleed off (dribbling) during the shut down and they need fuel sorta like a prime
Second video is of a boat..and injector spray pattern testing. Listen, for years my 6v92 would miss a little on startup and then all cylinders would fire. It was noticeable but I drove her for years that way (mainly when it was cold tho).
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@scott Re:second video, it showed smoke from the exhaust due to poor spray pattern, so I was thinking, maybe I'm getting a poor pattern on startup. Now thinking from @luvurbus's comment that it could be from low pressure due to the fuel dribbling off. Also thank you on mentioning this is not uncommon, my biggest fear of course is having some catastrophic engine issue. I figure so long as she makes good power, runs clean, I'm good to go for the big picture.
Maybe a bit more context here overall. When I first got the bus, and even now if I would let it run in this condition, it will run like this for a while and then in a cloud of white + black grey smoke it would roar to life and then clean right up. It seemed to take 2-4 minutes for that to happen. I can seem to shorten that up by doing a few start / stop cycles.
What injector number is in the 6v92 ?
Don't know, how can I tell?
Pop off a valve cover and check the tag on the injector
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Plug in block heater for 4 to 5 hours after it sets overnight and try it and see if any difference. Could be a low cylinder or two.
Probably tried injector or two.
I have had the same problem. I have also had the engine cutoff before all the cylinders caught up. I would have to prime the engine to get it start. I think Luvrbus has the right idea. Mine didn't miss every time I start the engine, so I think the cam/rack position on the injectors that leak down cause them to leak or not. The engine heater seems to make a difference.
I did replace three injectors and that has appeared to help, but not eliminate totally the missing on start.
If that makes no difference, then consider an injector issue. I would check all valve and injector settings with your gauges or have them checked. Then you can think about pulling injectors and have them tested and replaced if necessary. Do the cheap diagnostics first.
How much oil are you using? Do your air box drains go to the ground or into a canister? In other words, are you using a lot of oil?
If not, I would not worry about it. The video shows a well used engine. Until you start using a lot of oil you can get by.
Does anybody swap out injectors for rebuilts? Shouldn't be too expensive or difficult to do. It's always good to have a test stand to test the replacements. White smoke = bad injector.
Quote from: Geoff on May 07, 2018, 06:07:51 PM
How much oil are you using? Do your air box drains go to the ground or into a canister? In other words, are you using a lot of oil?
If not, I would not worry about it. The video shows a well used engine. Until you start using a lot of oil you can get by.
Just changed the oil , I think the PO had a multi grade in, since the change it leaks less from the airbox drains, consumes much less as well.
any chace you are getting some fuel in your oil?
Quote from: chessie4905 on May 08, 2018, 04:43:42 AMany chace you are getting some fuel in your oil?
There's always the "white paper towel" test for that.
Let it sit unless you intend to DRIVE it!>>>D
Am wondering if we have another tired engine here. With turbo and wound up it runs clean. Oil getting past the rings burns nicely also.
It's painted red like a GreyHound rebuild ,he has nothing to worry about just run it till it gives up that's all he can do
Obviously I have very little experience I've just been reading and learning, nothing replaces real world experience of course. From everything I've read it's not uncommon for an engine to smoke from poor compression / incomplete fuel burn when cold. Once I do the start shutdown cycle a few times , even while cold (even down to below freezing), mine doesn't do that, no smoke out the airbox drains, no pressure to speak of from the oil filler tube. To me that means my rings and liners are in good shape still. These are all no load observations of course.
PO was band, they took it to TX and back a few times I guess, but I called the Transit Company they bought it from. They told me they never rebuilt it, axel odometer says 127k or so. So if it's rebuilt it would be from Greyhound.
You know I've been thinking about some thing off and on and now again. It's about the fuel I've been using. We have a local BP that was shut down for a year or more, then was re-opened and they undercut everyone around on fuel, especially diesel. So I filled up there mostly, and it really starting acting up after a tank or two from there, I used a tank or so last fall.
Could old diesel be an issue? The fuel filters are freshly changed last summer (500 -600 miles on it or so) I've read about new diesel being less lubricating. Could untreated diesel / new formula or old stale diesel be possibly causing injectors to stick a bit on start up?
The new fuel doesn't cause a problem only with the filters.The GreyHound rebuilds really scare me sometimes,the largest over size bearings you can buy from DD or aftermarket are 0.020 and I have seen Greyhound engines with 0.060 mains and rods they must have a manufacture that makes those just for Greyhound.They got their money out of the cranks for sure
Well I'm happy to report, with the help for Scott Crosby ( Busgreasemonkey.com ), that I'm probably being just paranoid. He took a look and listen to it run today and said it sounded great, purred nicely. He's gonna give it listen in the morning with a proper cold start, so we'll see for sure then. But he all but ruled out the rack or injectors being an issue.