Hello,
I've got a 1990 MCI 102c3 with a 6v92TA engine that my band uses as its tour bus. The past few days I've been noticing some smoke, white-ish when I start it, then looking darker after I've driven a while (and generally only showing up when I floor it). Two nights ago it got noticeably smokier, but was still running strong. Then last night I started losing power on the highway and suddenly kicking out massive amounts of smoke, even started filling the cab, so I got off the next exit and saw it was mostly spilling out around the engine compartment, not the tailpipe. I opened the engine compartment doors and it looked like the smoke was mostly coming out from above the engine, blowing down from the fans (or maybe the fans sucked it up there and shot it down, I don't know, it was so smokey and hard to see). I parked at a gas station and am now writing from a Motel 6 on a Sunday morning.
I'm curious if anyone has a guess as to what might've happened, but mostly I'm posting here to see if anyone knows a good mechanic in the Indianapolis area? I fear we're going to need some major engine work, so want to go somewhere reputable. I'm willing to have it towed to another town, but of course I want to keep costs down, so hopefully won't have to go too far...
Thank you!
Aaron W.
I've been using Interstate Power (istate.com) in Milwaukee for our coach. They have a location in your area. They're not the cheapest, but they seem to have a good staff and parts network. The most important thing is to be sure and fully communicate with the tech (not just the service writer) so that everyone is on the same page and knows what you want them to do.
Richard
1974 GMC P8M4108A-125 (Current bus)
1964 GM PD4106-2412 (totalled Sept 2017)
Located in beautiful Wisconsin
KD9GRB
Man are you LUCKY! You could not have broken down in a better location. KING BUS MONKEY Scott lives in Avon, a west side suburb of INDY! Which Motel 6 are you at?
My guess is that you have a clamp busted or loose on the turbo. (or some other major exhaust leak)
Scott should be able to get it figured out and fixed up pretty easy.
You should send him a contact name & #.
:D BK :D
I second that BK
OH I forgot not everybody knows about or is on busgreasemonkey.com
You should go over there and sign up Scott is the owner of that board and will respond to you there quicker than here. (he is a member here, but doesn't hang out here as much as the rest of us)
;D BK ;D
Doesn't sound major maybe a broken exhaust pipe or bad turbo but you should have heard a broken pipe
Thanks for the replies everyone---Quick update: went out this morning to start the bus in the daylight and saw that yes, one of the exhaust pipes had busted clear off near one of the clamps and was spewing out the smoke, while also spraying a bit of diesel. Does that sound like a bad injector?
I wrote Scott, and tracked down a place called "Stoops Freightliner" who says they work on buses. Not the best reviews online & the labor rate is high, but it's the only place open on a Sunday, so I might have it towed there...
thanks again, Aaron
Just not enough air to burn all the fuel,which pipe broke the one with the expansion bellows is a high dollar puppy around 500 bucks
You might just have a broken exhaust pipe. Can you take a video and post it here of your engine compartment while it's running?
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Quote from: B_K on October 29, 2017, 07:07:25 AMOH I forgot not everybody knows about or is on busgreasemonkey.com
You should go over there and sign up Scott is the owner of that board and will respond to you there quicker than here. (he is a member here, but doesn't hang out here as much as the rest of us)
;D BK ;D
It needs an Invitation Code?? It says that an existing member must send me one. BK or anyone? I'd like to have access to BGM website. Thanks
I tried to read some posts you need to be a member just to read there.I read his posts on F/B sometimes so there is no need for me to belong to another board ,you can find about anything about buses on F/B fwiw
Quote from: Oonrahnjay on October 29, 2017, 08:37:24 AM
It needs an Invitation Code?? It says that an existing member must send me one. BK or anyone? I'd like to have access to BGM website. Thanks
sent you a code check your email or message here
I'm too busy at the photo studio this week to get to that, but it sounds like an easy enough fix it doesn't take a 2stroke guy to fix an exhaust.
https://www.avonpicturethis.com (https://www.avonpicturethis.com) if you need a photo session ;)
Quote from: Oonrahnjay on October 29, 2017, 08:37:24 AM
It needs an Invitation Code?? It says that an existing member must send me one. BK or anyone? I'd like to have access to BGM website. Thanks
I never knew about any invitation code. But just tell'm BK sent ya!
:D BK :D
Quote from: aaronjweiss on October 29, 2017, 08:11:51 AM
Thanks for the replies everyone---Quick update: went out this morning to start the bus in the daylight and saw that yes, one of the exhaust pipes had busted clear off near one of the clamps and was spewing out the smoke, while also spraying a bit of diesel. Does that sound like a bad injector?
I wrote Scott, and tracked down a place called "Stoops Freightliner" who says they work on buses. Not the best reviews online & the labor rate is high, but it's the only place open on a Sunday, so I might have it towed there...
thanks again, Aaron
Hope you didn't waste $ having it towed to Stoops!
If you absolutely had to take it too Stoops, you can drive it easier than towing it.
If it were me I'd take off the broken pipe and take it to an exhaust shop the can either build you a new one or weld up the old one.
If you could post a picture of the broke one I might just happen to have a used take off on the shelf in my shop.
;D BK ;D
It's more than a simple broken exhaust.
--Geoff
Quote from: Geoff on October 29, 2017, 06:28:53 PM
It's more than a simple broken exhaust.
--Geoff
Geoff you could be absolutely right, but I have trouble seeing that from what has been posted so far.
And I still say Stoops is a waste of $ they ain't seen a 2 stroke since the '90's and NONE of their technicians can diagnose anything that their laptop can't hook into and give them the answers.
;D BK ;D
Quote from: eagle19952 on October 29, 2017, 01:43:37 PMsent you a code check your email or message here
Got it - thanks!
Turns out Stoops turned us away saying nobody there works on two-strokes, we got it towed (after having the fire dept. called on us twice) to a place called "East Side Welding" that does a lot of work on old buses. They took out all the injectors on the problem side and one of them had a broken off tip, and now we're getting low compression in that cylinder. They said tomorrow they'll pull the head off to take a look inside to see if the broken off tip caused some internal damage.
My friend suggested that since they're gonna have the head off to consider getting new sleeve kits for the 3 cylinders on that side. I don't even know what that means, so couldn't even offer an educated response. Anyone have any thoughts on that? The engine was last rebuilt in 2003, but I have no idea how many miles since then. (In case you haven't noticed, I don't know much about my own engine!)
:-\
Thanks again for all the replies, Aaron W.
That'll do it. Sorry about the drama and fire department calls. What a pain. Some of the more knowledgeable guys will chime in here on the next step. I would listen to them carefully so that you aren't wasting time and money.
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I would say why no. Ultimately the point to a rebuild is to replace all the wear components, so she's good for another 500k. Often people pull a head and rebuild the top, this creates more compression but puts new stress on the old components, like bearings and rods that wasn't there before in the bottom end.
My point is, I would just rebuild the entire motor or fix the immediate problem and get back on the road. That tip should come out in an oil change.
My 2ce
Jay
The tip when it blew if you are lucky just chipped one of the 4 valves is the reason for low compression,he can tell more when he pulls the head
Quote from: luvrbus on October 31, 2017, 06:43:39 AM
The tip when it blew if you are lucky just chipped one of the 4 valves is the reason for low compression,he can tell more when he pulls the head
have they pulled the air box covers check for stuck rings...
pressure test the head
verify the injector coppers/tubes
actually look at the valve seats and valves
no. i would figure out a whole bunch of things before willy nilly kit replacing on 3 holes...
Take it one step at a time, let them inspect for what is actually damaged and what really needs to be replaced. It would seem foolish to put liners on only one side, that would open up a hole can of worms and cost. You will find out soon how honest and frugal this garage is, or whether they will try to sell you on an overhaul that may or may not be necessary. In either event, you better brace yourself for a nice bill.
did the tip go thru the turbo...have they looked ?
Here we go... another lamb to slaughter...
Aaron, in the name of all that is holy, before any work, or decisions get made, PLEASE, get on here with the shop's diagnosis, and EXACTLY the methods that were used to arrive at their conclusions.
Tell the shop up front, you have to check with "your friends" and that this might take a little time.
The smartest of us, send Aaron your telephone number via a private message.
Aaron, you know how to use the "my messages" in the blue tabs up there?
We must prevent a wallet emptying...
happy coaching!
buswarrior
After going through something similar back in spring. My 8V92TA was blowing oil out the drain tubes big time. Started on one trip. I'm second owner of my 1991 coach. Replaced check valves and didn't help. Used/blew a gallon out in 100 miles coming home. A lot of folks said overhaul time. Engine had 86,000 miles since new. Took it to Stewart Stevenson , San Antone and although big bucks, a lot cheaper than overhaul. Blower seals. Have driven it 1500 miles since and hasn't used a drop of oil. The foreman said if it needed a overhaul could have run up to 25 or 30 thousand. Yikes. Hope the best.
Hey fellas, thanks for all the input, have attached a few pictures. They took the head off and found that one of the valves was broken and another bent. Also, there's some damage to the piston. It doesn't look too serious to me, but I'm new to all this (and about 700 miles away now), so don't trust my own assessment, but my friend (who's there with the bus) said he's concerned it would fail at some point, so he thinks it's worth replacing, and in fact he's still pushing to rebuild all 3 cylinders on that side. The mechanic there said the engine looks young, so I'm not convinced doing all 3 is worthwhile (or even 1 for that matter. It might still be possible to simply fix the valves & put the head back on). More importantly to me, my band has a tour starting a week from today, and sound like it'll take a couple days just to get the parts...
A few questions: 1) I'm curious how serious a danger these gouges in the top of the piston are--is it a decent option to consider leaving it alone? 2) Assuming the rebuilt cylinder(s) will have better compression than the older ones, is that imbalance a detriment to the engine? And 3) if so, would it be better to have one cylinder stronger than the other five, or three cylinders stronger than the other three?
I'm also curious how to prevent another fuel injector tip from breaking off in the future...any thoughts on that would be much appreciated!
ps. buswarrior, yes, I'm somewhat familiar with the "my messages" tab, would be happy to talk to anyone about this.
Is that milky oil I see? The oil pan needs to be dropped and the bearings/crank inspected. And was the engine using a lot of oil before the failure happened? These questions need to be answered before a decision is made.
--Geoff
Quote from: Geoff on November 01, 2017, 07:23:38 AMIs that milky oil I see? The oil pan needs to be dropped and the bearings/crank inspected. And was the engine using a lot of oil before the failure happened? These questions need to be answered before a decision is made.
--Geoff
This was my first impression, too. A lot of the comments have been "get back on the road quick" or "do it cheaply" but a failure like this needs a complete inspection. (And, IMO, any piston that's been banged hard enough to be dented is very likely to damaged - cracked, piston ring lands distorted so that rings are pinched, skirts bent so that the lower part of the piston may scuff on the bore, etc. - and should be inspected carefully; or maybe even changed even if it looks OK.) I don't think I'd trust anything in that cylinder; valves, valve springs, pistons, rings, sleeve.
It is far better to rent a couple of vans for the band to do a few gigs than to have an entire engine grenade a few thousand miles down the road. Don't rush it.
Just my opinion but being cautious here could save you a lot of money in the long term. BH
That 1 liner and piston set needs to be replaced so pull the pan the rod is probably bent too like Geoff said check all the bearing.
Have the shop check the others if they check out, it is common to replace 1 liner or all the liners (3 or 4) on 1 side of the V engines it doesn't hurt a thing
Scott probably has a liner kit in stock. He has a bunch of DD parts he bought a little while back. Not sure about a head.
I have a 6V92 in my shop that the turbo went bad on and we were getting water out of one side of it afterward. I have never taken it apart, but one head may or not be OK.
I'm with Clifford and Geoff that the pan needs to come off and check the bearings and rods. Pretty sure Scott could help supply or locate parts needed. (after all that is his backyard. BTW I have no knowledge about the shop doing the work, as I moved out of INDY 30 yrs ago and I lived on the west side in the Speedway area)
;D BK ;D
Quick update: the shop hasn't finished the engine yet, so we went ahead and rented a moving truck & van to start off the tour (which is costing us lots of $ on top of the engine repair :-[). They replaced the broken valves, and 3 cylinders & sleeves and bearings---today they started the engine and it ran w/ no smoke but now no oil pressure (they double checked w/ mechanical gauge). They think it's either the bearings were the wrong size or a bad oil pressure regulator---any other ideas of what this might be? They're going to open up the oil pan tomorrow, I just figured it'd be worth asking on here in case there's other possibilities they might've missed.
Thank you! A.
I'd be disappointed if they hadn't checked bearing clearance before putting together.
Quote from: chessie4905 on November 08, 2017, 06:32:42 PM
I'd be disappointed if they hadn't checked bearing clearance before putting together.
if they didn't check before ordering parts...and again before putting the pan back on...
i'd be a lot more than disappointed. >:(
Ugh I hope they know what they are doing working on a two stroke.
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Ugh! Zero oil pressure? Something ain't right with this picture. Maybe something wrong with the oil flow up top, but generally I'd say, for them to tell you they ran the engine with no oil pressure is a bad, bad sign.
They did use straight 40 weight or 30 weight for winter? Was it zero or very low? At idle or higher rpms?
aaronjweiss What was found once they dropped the pan?
Just got word they replaced the oil pressure regulator valve and now we've got pressure again. A week and a half and $6,500 later, looks like we're getting our bus back, my friend's currently driving it to our show in Columbus, OH. All things considered, I'm feeling good.
To chessie4905's question, they're using straight 40 weight, which is what we always use---is 30 weight a good option in cold conditions?
Also, we sometimes pour some of that Lucas oil stableizer in there--any opinions on the benefit/harm of that product?
Thanks again for all the input fellas!
-Aaron
That oil stabilizer is like STP, and slightly thickens oil and raises oil pressure slightly. 30 weight is recommended by DDA when operating temps are below 32°F or something like that.
we used 30 wt in the Arctic.
a good motor with good compression (which yours has to be better) and decent battery i would run 40 wt down to 10 degrees or even 0.
provided you warm it up at least long enough to build air.
I would not put the lucas in until the new piston , sleeves are broke in
dave
Quote from: sledhead on November 10, 2017, 04:37:42 AM
I would not put the lucas in until the new piston , sleeves are broke in
dave
i wouldn't use it even then.
Busnuts in the lower 48, just use 40 wt.
What busnut in colder areas of the lower 48 wouldn't have some form of engine heater?
Find something else to obsess over, proudly run 40 wt and plug in an hour before starting if it is sub-freezing?
happy coaching!
buswarrior