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Topic: C8.3 Fuel Shut Off Solenoid Troubles Part II  (Read 1763 times) previous topic - next topic

C8.3 Fuel Shut Off Solenoid Troubles Part II

About 18 months ago I replaced the fuel shut off solenoid on my 1997 Cummins C8.3 after a partial failure. It would start and run, but the solenoid was not fully opening so it only went abouft 10 miles per hour. I changed fuel filters, no change. After posting my troubles on the forum among the possibilities was a bad fuel shut off solenoid (didn't know I had one.) The boot protecting the spring was shot and it was old and crummy looking. I ordered a replacement from Amazon that was about $35 instead of over $500 for a Cummins part. The eye bolt that attaches to the fuel shut off linkage did not fit, so transferred the old one over to the new one. After some adjustments it worked fine until this week. The Amazon part number matched my original. Cummins, however, no longer sells that part, but has a new and improved solenoid with a newly designed bracket.

On Monday I got in line at Quartzsite to dump my tanks. It was a long line and I started and stopped the coach six or seven times waiting my turn. After dumping I moved up to the water fill station, filled up and then the coach failed to start and run. It would start, but immediately die. I primed the pump, thinking maybe I had an air leak somewhere. I would pump it up, it would start and immediately die. This went on for thirty minutes before I wire tied the fuel shut off linkage open. It started and ran, and we sheepishly left the water fill station grateful to be moving at last.

Back at the Lemon Ranch I started digging into my problem and cruising through YouTube Videos on fuel shut off solenoids. I learned there are two coils triggered by two separate signals. The coil has three wires, black (ground), white (pull up), red (hold up). White is connected to the starter circuit and energizes the coil that pulls up the shut off valve to full open. Red is connected to the run (ignition on) signal and holds up the shut off valve in the run position. My solenoid showed .4 ohms between ground and the white wire, open circuit between ground and red wire. This explained the start and die sequence at the water station.

I tried to order another solenoid from Amazon, but it was going to take two weeks. The CAT shop in Blythe said my part number wasn't in his system and he would have to do some research. I went back to the forum and ran across a post about LarryB's as an aftermarket supplier of fuel shut off solenoids. Part #FS20-RP-12(Volt) was an exact match. The solenoid comes with the correct connection bolt and the wiring connection – plug and play. It also came with new brackets and shut off linkage. Even better, clear instructions for installation that explains how to set the bolt length! It arrived two days after ordering online by Priority Mail, well packaged. Total cost: $140.00 with shipping. The owner even answered my text about shipping and confirmed this was the correct part. Larry Buck Inc. PO Box 865, Vaughn, WA 98394. 253-2256-9962 is his cell number.

I'm hoping the LarryB will be somewhere between the Amazon solenoid and the Cummins in quality. If you go the Amazon route, buy at least two. By the way, two people here at Quartzsite offered me their spares if I couldn't get one in time. Lots of support and sympathy here.

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #1 –
Patrick,

Thanks for the graduate course in fuel shutoff solenoids.  I certainly learn a lot from this forum nearly every day. 

Richard

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #2 –
Quote from: Realmccoy –
I'm hoping the LarryB will be somewhere between the Amazon solenoid and the Cummins in quality.
I'm sure you will be fine with the LarryB part.  I have purchased several items from his web page, and they were all excellent quality.

Buying genuine CUMMINS parts, in many cases, only means you pay extra for the name on the box.  The contents are still made in China.  I'm NOT saying this is a bad thing!  Nine years ago I replaced the fuel shutoff solenoid on our coach with a genuine Cummins part that I found on eBay for $70.  After I opened the box I saw it was made in China.  Has functioned perfectly since then, so I'm a happy camper.

Good Price for Fuel Shutoff Solenoid?

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #3 –
When I had the Monaco the pull in winding was iffy, sometimes it would work and sometimes
it wouldn't. When it wouldn't I just opened the bed with the ignition switch on and pulled it in
until I head the click and then started the coach. Finally it quit. If you are stuck you can wire it in.
I had one go and so I wouldn't have to keep wiring it up I used a spring to hold it in the run
position and used a pull cord to shut the engine off. Worked great.

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #4 –
I have one of Larry B's on mine, flawless performance

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #5 –
Follow on to Realm posting, we put the white pull-up, starter-energized wire on to the normally closed points of a relay. While cranking engine, we hold a momentary dash pushbutton switch that energizes this relay to keep the fuel shutoff solenoid coil from opening. And after a moment while continuing to crank engine, we release the dash switch to allow fuel to flow and engine always immediately starts.

We call this action our pre-luber, to allow engine oil pump to put some oil on bearings, etc. before they are loaded from running. Especially helpful after engine has been off for a length of time.

BTW, we have on more than one occasion, cable tied fuel solenoid up to start engine, and then later cut cable tie to stop engine, repeating this for over a week until new solenoid can be installed. This only works with C-8.3 Cummins engine. For this engine, always look for a partially pulled-up fuel solenoid when coach max speed is about 10 MPH. Much quicker than changing fuel filters, etc.

Speaking of "normal" extended driving work-arounds, when engine alternator fails, just run diesel generator with boost switch so that inverter/battery charger will keep both battery banks under charge. We have done this for over a week until we could get alternator rebuilt. Knowing about extended workarounds can take a lot of stress out of RV ownership.

Also, we never turn off engine in truck stop fuel fill lines, dump lines, etc. as an engine failure to start can be very stressful, and engine is happy running at idle RPM for extended times. Every good start brings a satisfied smile, reminding us sometimes it won't start.

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #6 –
I also have used Larry B heavy duty starter contact parts in my 1994 Dodge P.U. with the12 valve 5.9 Cummins. every 75K miles the starter contacts would start acting up. Changed out starter contacts to Larry B heavy duty starter contact parts and that was the end of the starter issue's. He has some quality parts.

I also had a problem in 1994 when the truck was new, the fuel solenoid wouldn't pull up some times and would drop out,      We had just come out of a restaurant and the truck wouldn't start. It was almost dark, I was going to have my wife crank the truck while I pulled the fuel solenoid valve up, out of a corner of my eye I noticed a spark at the front of the engine it was a bundle of ground wires bolted down to the head. So make sure you have a good ground for the solenoid it will act as if it is bad. I cleaned the ring terminals and tightened down the bolt and that was the end of the fuel solenoid problem.

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #7 –
Took the coach for a short run today to dump and fill water tank. Ran like it should.

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #8 –
hi, the cell phone number has 11 digits does not sound right do you have correct number please
Quote from: Realmccoy –
About 18 months ago I replaced the fuel shut off solenoid on my 1997 Cummins C8.3 after a partial failure. It would start and run, but the solenoid was not fully opening so it only went abouft 10 miles per hour. I changed fuel filters, no change. After posting my troubles on the forum among the possibilities was a bad fuel shut off solenoid (didn't know I had one.) The boot protecting the spring was shot and it was old and crummy looking. I ordered a replacement from Amazon that was about $35 instead of over $500 for a Cummins part. The eye bolt that attaches to the fuel shut off linkage did not fit, so transferred the old one over to the new one. After some adjustments it worked fine until this week. The Amazon part number matched my original. Cummins, however, no longer sells that part, but has a new and improved solenoid with a newly designed bracket.

On Monday I got in line at Quartzsite to dump my tanks. It was a long line and I started and stopped the coach six or seven times waiting my turn. After dumping I moved up to the water fill station, filled up and then the coach failed to start and run. It would start, but immediately die. I primed the pump, thinking maybe I had an air leak somewhere. I would pump it up, it would start and immediately die. This went on for thirty minutes before I wire tied the fuel shut off linkage open. It started and ran, and we sheepishly left the water fill station grateful to be moving at last.

Back at the Lemon Ranch I started digging into my problem and cruising through YouTube Videos on fuel shut off solenoids. I learned there are two coils triggered by two separate signals. The coil has three wires, black (ground), white (pull up), red (hold up). White is connected to the starter circuit and energizes the coil that pulls up the shut off valve to full open. Red is connected to the run (ignition on) signal and holds up the shut off valve in the run position. My solenoid showed .4 ohms between ground and the white wire, open circuit between ground and red wire. This explained the start and die sequence at the water station.

I tried to order another solenoid from Amazon, but it was going to take two weeks. The CAT shop in Blythe said my part number wasn't in his system and he would have to do some research. I went back to the forum and ran across a post about LarryB's as an aftermarket supplier of fuel shut off solenoids. Part #FS20-RP-12(Volt) was an exact match. The solenoid comes with the correct connection bolt and the wiring connection – plug and play. It also came with new brackets and shut off linkage. Even better, clear instructions for installation that explains how to set the bolt length! It arrived two days after ordering online by Priority Mail, well packaged. Total cost: $140.00 with shipping. The owner even answered my text about shipping and confirmed this was the correct part. Larry Buck Inc. PO Box 865, Vaughn, WA 98394. 253-2256-9962 is his cell number.

I'm hoping the LarryB will be somewhere between the Amazon solenoid and the Cummins in quality. If you go the Amazon route, buy at least two. By the way, two people here at Quartzsite offered me their spares if I couldn't get one in time. Lots of support and sympathy here.

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #10 –
I carry a Larry B's just in case.

Re: C8.3 Fuel Shut Off Solenoid Troubles Part II

Reply #11 –
Yes, Larry sells a good one.