| Author |
Message |
Gary Stadler (66.82.168.1)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 03, 2003 - 11:12 pm: | |
SO I'm driving the Grapevine today in my Crown with Cummins 220, now turbo'd, all is very well. I get to the top, and strart down the 6% grade. all is well. I use my exhaust brake and never touch the brakes...the engine is just about max RPM all the way down. I get to the bottom, and finally when the hill is over, I step on the gas...NOTHING... no poop, totally nothing! Fortunately there is still some mild grade and an offramp about a mile away, so I coast towards it. All the while I try engaging the engine to see if it will kick in, I turn the ignition switch off for a few seconds, turn it back on and pop the clutch, NOTHING... I try it a couple of times, and just as I'm about to turn off on the ramp, the engine suddenly lights up as if nothing ever happened, and I then sucessfully drive 7 more hours without so much as a bad burp. WHAT HAPPENED HERE? I'm totally clueless. tank was 1/2 full of gas, fuel filter was new 2000 miles ago, no problem at all after the occurance, I'm totally puzzeled. The only thing I can come up with is that I might have coasted down just a few RPM over max once or twice, and maybe the combo of the governor being higher than it wanted to with my foot off the gas made someting in the PT fuel system stick, get a bubble, cavitate, ???? ANy experts out there? I'm a bit shy now although it performed flawlessly after that.
As an aside, this was the first run with my newly installed "altitude compensation turbo" that keeps the intake manifold between 3 and 10psi no matter what the altitude. It worked perfectly. As a matter of fact, the only effects I see other than no more loss of power at altitudes is that there is NO MORE smoke out the exhaust no matter what I do, and amazingly my usual 10-11MPG went up to 13.5 MPG averaged over 500 miles or so! No kidding, I didn't believer it myself so I fueled up a few times and did the math...13.5!! Shows you how much black smoke is a waste of fuel!!
Anyway, if anyone has a clue about the engine crap-out, please PLEASE let me know... it's driving me nuts thinking about it!!
Cheers
Gary |
R.C.Bishop (128.123.221.196)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 03, 2003 - 11:30 pm: | |
Gary, if it is set up like my Jake, it probably shut down when the RPM's got too low. It has taken me a couple of years to figure that out, but it is the case with mine.
FWIW
RCB |
Geoff (Geoff) (66.238.120.25)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, August 04, 2003 - 7:44 am: | |
It sounds like the fuel solenoid shut off acted up, or the wiring to it has a bad connection somewhere. Your compensating turbo sounds great-- quite a few people have talked about putting them on their 8V71's but you are the first one I have ever heard that actually did it.
--Geoff
'82 RTS CA |
two dogs (67.30.23.83)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, August 04, 2003 - 8:39 am: | |
know you already know this,anytime a diesel quits running,it's out of fuel....my guess would be the fuel shut off valve,anyway that's what I'd check first |
JD-Crown.GA (66.32.118.140)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, August 04, 2003 - 10:12 pm: | |
Sounds like two dogs is on the right track. Our Cummins 220 has only one wire- if your solenoid is going bad or the wire is loose, it'll shut it right down. Thank goodness it has an emergency bypass! (screw on the end)
Aside from that, do you have some links on how you did the turbo? Sounds like a worthy thing to do to my Crown!
Jim |
Tom Caffrey (Pvcces) (64.114.233.99)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, August 04, 2003 - 10:46 pm: | |
Gary, what about the valve that applies oil to the jake system sticking on? If it did that, you'd get absolutely no power if all the cylinders were shut off by the Jake, until it came unstuck.
Somebody who know how all those pieces work together could probably figure out if this was possible. Our Jake quits when the oil pressure drops too low to open the valves, but we've never had it stick on.
For what it's worth.
Tom Caffrey PD4106-2576
Suncatcher |
Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 05, 2003 - 6:48 pm: | |
Gary...my best guess also is that you got a continunity problem with the wiring on the shut down solenoid. Power on for fuel, no power, no fuel
I know you have an exhaust brake and not a Jake, soosss hopefully it is not related to the Jake brake which you do not have.
Another possibility???? Have you changed out the key operated "ignition" switch? (starter switch) Could it be a 40+ year old key switch causing the problem?
Something is causing the mill to simply shut down. No fuel at all. Anothing related to this could be the problem. My Crown has a separate starter...
...starter key switch and a starter button. Gots to use both hands to crank the Cummins. What size tee shirts do you both wear? CROWNS FOREVER!! Henry of CJ |
Derek (24.66.241.23)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 05, 2003 - 7:45 pm: | |
Correct me if I'm wrong, but isn't an exhaust brake a 'jake brake', or Jacobs brake? |
Tom Caffrey (Pvcces) (64.114.233.97)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Tuesday, August 05, 2003 - 9:28 pm: | |
Derek, no they're not. I apologize for not reading the first post carefully enough.
A Jake releases compression; the exhaust brake blocks the exhaust. They are two different animals.
Tom Caffrey PD4106-2576
Suncatcher |
Derek (24.66.241.23)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 06, 2003 - 1:58 am: | |
My mistake, I'll keep that in mind. Thanks! |
Gary Stadler (66.82.168.1)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 06, 2003 - 8:02 pm: | |
Well guys, thanks for the ideas. I seriously doubt that it's my electrical shutoff solenoid, there has been zero electrical problems with it ever, and for the rest of the trip, no problems either. Althought I'll never say "never", it's been rewired and soild as a rock for as long as I've had the bus. Plus if it was the problem, I'd surely have had trouble on the rest of the trip.
The best thing I can figure is that maybe the combination of foot off accelerator and perhaps going over the governor limit somehow either caused the fuel pump to stick something shut, or cause a bubble somewhere that made it loose fuel pressure. I do remember one time last year, I was driving down the road and turned the igniton off momentarily to reset the speedometer, and something similar to this happened... Anyway, I was hoping for an old Cummins Mechanic to see this and say "sure kid, this is what it was"... Henry, does your old Cummins expert have a clue?
I'm on vacation right now till mid september. When I get back I'll write the turbo install up with photos. It was actually a very simple modification- Garrett sized the thing to my requirements, and with a couple of adapter plates and a redo of the intake and exhaust systems, it just dropped in and worked. It's almost un-nerving not seeing any smoke out the tailpipe any more! (and I still find it hard to believe the 13.5 MPG but it's right there on the gas receipts!!)
CHEERS
Gary |
Scott Whitney (66.82.9.11)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 06, 2003 - 8:05 pm: | |
Hey Gary, you are on-line! Hurray!
Scott |
Henry R. Bergman, Jr. (Henryofcj) (63.164.175.167)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Friday, August 08, 2003 - 4:50 pm: | |
Gary, I will ask my local retired master Cummins mechanic about the overspeed potential of shutting off the fuel on your 743 220. Will have an answer by tomorrow, Sat, 9 August.
How many rpm were your tacking when the problem occured? Might help him figure out what is wrong Maybe your injection pump just quite injecting due to rpm...
...or the injector cups did not have time to fill, which would cause the same type of problem. Kinda unlike vapor lock in a gasser. No fuel. CROWNS FOREVER!! |
Stephen Fessenden (Sffess) (65.130.8.108)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 10, 2003 - 2:54 pm: | |
Are you sure your exhaust brake does not have a mechanism, mechanical or electrical, to shut off the fuel when it is activated? I believe Jakes (which you do not have) shut off the fuel during braking. There is no point in burning fuel when you are trying to slow down. If this mechanism stuck, that would explain your problem best. |
JD-Crown.GA (66.32.117.47)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Sunday, August 10, 2003 - 10:29 pm: | |
The jake brakes for the Cummins 220 engine do not have a provision for shutting the fuel off. They're actuated when you take your foot off of the throttle by means of a microswitch. Mine blows off black smoke if you hit them at too high an rpm! No other model is available for this engine and jacobs doesn't make them anymore. The exhaust brake that came stock on the bus is a simple air operated mechanical unit. No wires. |
Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Monday, August 11, 2003 - 11:12 am: | |
Definitely no fuel cutoff- I installed the exhaust brake myself. This is *not* a Jake... it's the kind that simply plugs up the exhaust pipe when activated by an air-operated system, causing about 40psi backpressure in the exhaust system. It works great!.
I did my return trip yesterday and never experienced the problem again, although this time I was careful to never allow the engine to exceed maximum RPM when going down grades. I still suspect this had something to do with it earlier. Quite a mystery and I really get bugged with stuff like this that has no explanation. I'm considering adding a fuel system pressure gauge, this may shed some light on things...
Henry, my pump is set at 2400 RPM. Someone before me did that and I am going to leave it there, because although it's 300 RPM faster than spec, I really like the ability to go that fast especially with my weird gearing (5:29 rear end plus tranny overdrive to make up for it) If I lowered it to 2100 which is spec for the motor, I'd be constantly shifting between ranges in city traffic. I doubt the extra wear on the motor will ever be an issue in my lifetime...
When the problem occured, it probably got up to 2500 once or twice for maybe 5 seconds...
Oh, the fun part, ALWAYS check your aux. braking system prior to going down grades!!! I do it religiously. On the occasion just prior to this fuel problem, I checked my exhaust brake out at the top of the grapevine and it failed!!! Had you been there you'd have seen me sitting in the brake check parking area cutting a hunk of radiator hose into a nice fat disc to replace the old hardened activation cylinder's packing that had blown a hunk out. The joys of mickey-mousing... it took me all of fifteen minutes to R&R the cylinder and have it working flawlessly! Now that I'm back, the quest is to find a "real" packing gland for it, if it's still even made! Otherwise, the radiator hose will probably live there forever....
Cheers
Gary |
Henry R. Bergman, Jr. (Henryofcj) (63.224.197.10)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 13, 2003 - 5:57 pm: | |
Gary; our retired Cummins master mechanic told me the governed rpm of your mighty 220 743 now 275 or soosss is ok for occasional use. He saysss you can not really hurt the mill.
He thinks it may be fuel related, but caused by some sort of stoppage in the fuel delivery system. You were going down a 6% grade when it happened?
Maybe a flake of crud of something got caught in the works. He also said just because your solenoid seems ok, it might just be time for a replacement.
He also said a 40 year old plus starter key switch may also be due for routine replacement. Strange things have happened. It is great that your Crown still got you home OK. CROWNS FOREVER!! |
Gary Stadler (Boogiethecat) (68.7.217.217)
Rating: N/A
Votes: 0 (Vote!) | | Posted on Wednesday, August 13, 2003 - 11:17 pm: | |
Henry, yes, 6% grade for about 20 minutes. Then 1500 flawless miles in two segments, lotsa grades and straights.
Starter key plus entire dash is new wiring, I seriously doubt it's electrical. Thanks for asking him... It definitely felt fuel related. I guess it will just remain a mystery...
G |
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