Won't stay running unless fully aired up.

[luvrbus]

You have photos of your system ? you may have the Kysor system we went through this on the BNO not long along

[eagle19952]

You have photos of your system ? you may have the Kysor system we went through this on the BNO not long along

which presents more difficult trouble shooting quandaries

[lou432]

Hey guys, I was able to briefly run by there and take pictures and find the things that you all were so generous to post pictures of and here are the pictures of mine. Thinking this past week it did not have this particular issue until the first night I took her on the road. The only thing that changed from days past when she cries any time at any level was the high pressure steam cleaning of engine 1 hour before I left Florida on my trip back. Now tell me, what relationship does that have with the new issue we are working on? If any?

[lou432]

So it looks like the rear Skinner valve and picture is original or much older than the front one that has electrical wires coming into it so I'm guessing that is the valve to replace? Or am I understanding it wrong? Either way where would I procure one of these wonderful solenoid Skinner valves?

[eagle19952]

i seriously doubt that the skinner valve is your problem. having said that, those skinner valves are proprietary as in plug and play... finding ones that simply plug into those connections...won't be easy.

observing them is going to be your best bet to understand them...

it is a simple plunge action to extend that rod to shut off the motor and a spring inside assists it to it's resting position to prep it for it's next use...

[gumpy]

Ok, so what you have there is a Skinner valve attached directly to the control cylinder. The one on the left in the photo, which is silver and appears to be attached directly to the cylinder
with a piece of rigid pipe is the fuel shutdown. That lever which the plunger is pointing at is the shutdown lever. Incidentally, this is the lever you would push with your thumb should you ever need to shut down the engine manually, such as before the air pressure has built up. This cylinder is the one you want to be watching as your air pressure goes up. It should stay retracted as it is in the photo. If it pushes out and pushes on the shutdown lever at say 30 psi (which is where you've indicated your bus shuts down), then the electric Skinner valve behind it is probably sticking and needs to be replaced. They are interchangeable, you'll just need to find a replacement. They can be rebuilt, but they require some special tools to take them apart.

The electric Skinner valve in the back, the one with the green tinge to it, is attached to the fast idle cylinder which is the right hand cylinder in the second photo. That one is not part of this problem. Ignore it.

As for the high pressure steam cleaning, you could very easily have forced moisture into either the Skinner valve assembly. There's a mechanical plunger in that valve body and moisture in there could make it stick.

You could try removing the air lines from the Skinner valve and squirting some light oil in there. Many tout Marvel Mystery Oil. I have no experience with that. I would probably squirt a shot WD-40 in it to clean it, and then maybe a squirt of ATF or 10W to lubricate it.

[Scott & Heather]

^ read this carefully and slowly and you'll be able to rule out or confirm the engine stop cylinder as the issue.


Sent from my iPhone using Tapatalk

[Scott & Heather]

Video of me pushing my shut down cylinder. Hit play even if it says video not available. It works.

https://vimeo.com/166966362

Sent from my iPhone using Tapatalk

[lou432]

Craig, I understand completely your explanation thank you very very much! Along with Scott's video, Thanks !!  I believe I am armed with the  information to determine or  rule out the Skinner valves part in my issue. I'll be back in New Hampshire Friday evening and am looking forward to at figuring it out. I was able to air it up manually from underneath the driver side compartment. And she started just fine after 60 pounds or so.
   I will keep you posted when I have more info,  currently in Plattsburgh New York.
Thanks again gentlemen!

[lou432]

Well, finaly got time to check her out and heres what I did....
   Took air lines off both sides of front Skinner valve then backed the T off the top and shot a blast of WD40 then closed her up. Started her up and about 25 lbs the valve slowly came out then shut her down as in the past.
   My question is can/should I hold the shaft/cylinder back
   Long enough to build air pressure  and if so will it retrack?
    OK ... seems like the Skinner valve needs to be replaced/rebuil and im ok with that but presuming I can't/don't have tine and am stuck without shop air ,can I hold the  shaft back long enough to keep her running?
   Seem if air is high enough the shaft will not push out and assuming when pressure is high enough it will retrack? 
Just thinking out side the box I .
Thanks gents!!!
Picture  of cylinder at 30 lbs.
   

[Bob Gilbert]

When I start my eagle from the back and don't get up front  to
Turn on the switch it will die from lack of curet to the valve that
Controls the plunger that kills the engine, that is how it is suppose
to work. I would check voltage to that valve or for proper operation.
I never checked the pressure when it dies but would think it would
not take much. Good luck, Bob

[gumpy]

Bob has a good point there. The Skinner valve requires power to keep it closed. When power is cut (i.e. the master switch is shut off), then the valve automatically opens, allowing air to flow to the shutdown cylinder and push the fuel shutoff lever.

Before you start it, and with no air in the system, you should test the voltage at the electrical connector. If there is none, then the valve cannot close, and the result would be exactly as you experienced. This leads back to the safety shutdown system, as mentioned early in this thread. If per chance there is something else telling the system to shut down (e.g. oil pressure, water temperature, water level, etc), that could be causing these symptoms, though off hand, I can't come up with a scenario that would indicate one of these other sensors.

My money is still on the Skinner valve, but I'd also suggest you swap the two Skinner valves (shutdown and high idle) to verify the one is bad. If the problem persists, then it's not the Skinner.

As for starting it, as you asked, you probably won't be able to hold the plunger back with your thumb or fingers. You might be able to use a quick clamp, such as used for woodworking, and hold it back. Otherwise, remove the two screws holding the plunger cylinder down, and the screws holding the Skinner to the plate and you should be able to move the assembly out of the line of fire for the shutdown lever. Not very convenient, but in a pinch...

craig

[Scott & Heather]

Cool, now you're on the right track and are chasing down something likely fairly simple


Sent from my iPhone using Tapatalk

[lou432]

Thanks again guys! I was able to get over to her late on Sunday and experiment with the skinner valve and holding the cylinder back from pushing the shut-off. I could not get anything to hold such as C clamps or trigger clamps so I just took some 14 gauge electrical wire single strand with shroud around it and wrapped it around the steel brackets on the other side of the Skinner valve and then wrapped  around the shut-off. Then just took a pair of pliers and twisted the tension to tighten it like you would rebar ties . cranked her  up . The plunger did come out h
At about 30 pounds but could not push the shut off switch,  aired up no problems then went true engine and cylinder had retracted remove the wire she continued to run no problems. I will be taking her to her summer resting place at Oneida Lake just north of Syracuse. On Saturday. Then I will have time to figure out the Skinner valves this summer. I will keep you all posted on my travels to Syracuse. Thanks again and have a great Memorial Day weekend!

[Scott & Heather]

So to shut down you're reaching in there and pushing the lever right now?


Sent from my iPhone using Tapatalk