Onan Fuel shut down Soleniod

[Scary]

I'm having problems with finding a replacement solenoid for 16kw thirty eight year old Onan Generator. Onan is now part of Cummins and they are barely supporting these old generators with existing parts. They had a few of these in stock but with shipping the part came to over $500. The shipping nearly doubled the part cost. I'm looking for a more affordable solution. Any Ideas. I don't like getting ripped off when shutoffs for Ford, Chevy, and Dodge run around a $100 or less.


















4

 

[RickB]

Wow, are they buying the package a seat on American Airlines?

 

[N4712]

Remember it's "marine" grade.

 

[Ski in NC]

MDJ series? Solenoid may be available from OEM, and maybe old plunger can be reused.

 

[ksanders]

Steve

The way I used to fix these was to use a diesel rated fuel solenoid instead.


It worked just fine.

 

[Scary]

I had bought a soleniod on line that worked

I bought a solenoid on line that seemed to work. Unfortunately it gets hot and relaxes the plunger slowing the engine and eventually shutting down the engine down . I need a solenoid that can remain contracted for long periods of time. I can remove the solenoid and the engine runs fine. I just have to physically move the fuel shut down lever to stop the engine. I believe it is a MJD series. It's a great generator, starts well, oil remains clear, and it pumps out the power, just very few parts seem to be available. I'm going back to the boat this evening so I will see if I can get some pictures.

 

[Ski in NC]

If solenoid plunger cannot bottom fully when energized, it will get hot and cause trouble. Check that linkage is not preventing full travel.

 

[kulas44]

That selinoid is the biggest problem with this series onan genset. It uses a heavy wound "pull in" coil. It has a set of contacts that are pushed open by the plunger shaft, leaving the lighter wound "run" coil to hold the plunger. In my opinion, an exceedingly poor design. Usually what happens is the contacts stay closed and it burns out the pull in coil. Usually if you hold it in the run position, once it gets up to speed it will stay running. I have 2 of these MDJFs, 15kw, if anyone is in need of one. Or parts. I do not however have a working selinoid.

 

[BruceK]

Scary, Had the same problem with an MDKD 6.5kw solenoid, part no. 307-2546-00. Amazingly mine cost about $430 here, cheaper than your quote, everything costs more here(just heard a Coke cost 75c at LAX, $4.40 at Sydney airport).
Pretty sure I saw them online in USA around $300, but no one would ship here.I could start mine by pulling the plunger across, so the "hold after start" solenoid was working, but not the "pull in" one.
A friend was going to do a "work around", someone else was willing to modify a different one, then I found one at Cummins. Came in a box saying Genuine Cummins part. Labels showed it was made in China for someone else. But it works and I don`t visit the ER any more to start it.

 

[ksanders]

guys I do not know if anybody understood my post above.

All the solenoid does on that generator is push the rack back and cut off the fuel.

I have personally installed a simple fuel valve solenoid on these engines to replace the obsolete Onan part and it works just fine.

 

[hmason]

My 8 KW Onan genny also needed a solenoid. Got one made for a Westerbeke for half the price and it works just fine. Even the mounting screw holes matched up.

 

[Scary]

Thanks

I'M WORKING ON A SOLUTION. Thanks for the explanation as to the design of the stock solenoid. Now I know what to look for. Kevin can you recall where you accessed the solenoid?

 

[BruceK]

guys I do not know if anybody understood my post above.
All the solenoid does on that generator is push the rack back and cut off the fuel.
I have personally installed a simple fuel valve solenoid on these engines to replace the obsolete Onan part and it works just fine.

We may be at cross purposes, not sure.
Yes, the solenoid cuts off fuel to stop the generator. But first the generator has to start. That requires (apologies for non tech terms) the plunger to "pull cross" and hold its position, I`ve seen it operate. And seen it not do it,= no fuel no start. I`ve done the "pull across" manually. Otherwise no fuel, no running generator to stop.
There are also safety cut out interlocks which could inhibit operation.
I hope you can replace the original with an alternative and save some $.

 

[ksanders]

We may be at cross purposes, not sure.
Yes, the solenoid cuts off fuel to stop the generator. But first the generator has to start. That requires (apologies for non tech terms) the plunger to "pull cross" and hold its position, I`ve seen it operate. And seen it not do it,= no fuel no start. I`ve done the "pull across" manually. Otherwise no fuel, no running generator to stop.
There are also safety cut out interlocks which could inhibit operation.
I hope you can replace the original with an alternative and save some $.

Actually from the factory the rack goes to full throttle when the solenoid pulls in based on a spring. The flyball governor then pulls it back towards closed as speed increases. If memory serves, this spring is the large one with a length adjustor on the end of it. Adjusting the spring was one of two adjustments on that rather finicky governor, again, if memory serves correctly.

Remove the selonoid and the rack will operate just fine. Put a selonoid operated fuel valve in the fuel line and have that tied to the same relay that supplies power to the old selonoid and you are good to go.

 

[ksanders]

I'M WORKING ON A SOLUTION. Thanks for the explanation as to the design of the stock solenoid. Now I know what to look for. Kevin can you recall where you accessed the solenoid?

Steve, Its been years since I put one in, but ASCO makes a valve called a REDHAT that I know will work fine.

The way the factory electrical circuit works is simple.

The toggle switch activates a relay. That relay supplies power to both the start relay and to the fuel selonoid.

When the oil pressure comes up the oil switch closes allowing current to flow through the relay and you can release the switch.

Putting the switch in the other direction activates another relay that opens up the coil to the first relay, dropping it out.

Thats why they called it the ONAN 3 wire start system.

 

[FF]

All the solenoid does on that generator is push the rack back and cut off the fuel.

Anybody old enough to remember a push pull cable?

Sounds like a bronze choke cable would be robust enough .

If not a light weight throttle cable from an outboard should do , even if 35 ft long.

OF course if the noisemaker auto starts with each light bulb switched on , the solenoid may be needed.

 

[kulas44]

That works but it bypasses all of the safety shutdowns.

 

[rwidman]

I'm having problems with finding a replacement solenoid for 16kw thirty eight year old Onan Generator. Onan is now part of Cummins and they are barely supporting these old generators with existing parts. They had a few of these in stock but with shipping the part came to over $500. The shipping nearly doubled the part cost. I'm looking for a more affordable solution. Any Ideas. .......

You are saying they would charge you $250 to ship the solenoid? To where, the South Pole?

Something is wrong here, it can't cost that much to ship something that could ship UPS or FedEx. I would question them on the shipping cost.

Maybe you could find a friend or relative or even a forum member who could pick it up in person and then ship it to you.

If the problem with your solenoid is electrical rather than mechanical, you could take it to a local electric motor repair shop and see if they could rewind the coil(s). It wouldn't hurt to try.

 

[psneeld]

Often it's "shipping and handling"...$5 to ship, $245 to handle...

prerogative of the supplier...common on ebay...

 

[mbevins]

Yep they don't pay commission to eBay on the S&H charges, just the actual sell price.

Sent from my Nexus 7 using Trawler

 

[Scary]

Thanks All

I found out that Drake Controls makes the OME solenoid. They will not sell it direct, has to come from Cummins. It still is in production. I may have to bite the bullet. The original solenoid was made by Prestolite. The Drake control is made by Warner. The Westerbeke solenoid is worth looking into. Their parts aren't cheap.

 

[RickB]

Maybe a Woodward shop will sell you one:

http://www.drakecontrols.com/gas/solenoids/52132.pdf

 

[LarryM]

U S Autoelectric has a good selection of solenoids and might be worth a call:

Solenoid - Fuel shut off

And here is a link to the Woodward Solenoid Product catalog that might be helpful in identifying what you need:

http://www.woodward.com/workarea/downloadasset.aspx?id=2147484597

I have a Woodward solenoid on my Kohler/Yanmar generator that the PO replaced years ago and it still works perfectly.

Good luck on your project.

Larry
m/v Boomarang

 

[cajun mistress]

We bought a generator dor parts and it had a 36 volt.. We are using a 12 volt so if you can use the 36 volt let me know

 

[Scary]

Looks like I may have found a solenoid

Hope this works out. Kevin using the fuel shut of valve doesn't cause restarting problems? I guess as long as air doesn't enter the fuel supply, all is well. No heat generated by the valve to worry about?

 

[kulas44]

It wont work. The originall design is completely different.

 

[ksanders]

Hope this works out. Kevin using the fuel shut of valve doesn't cause restarting problems? I guess as long as air doesn't enter the fuel supply, all is well. No heat generated by the valve to worry about?

Steve

I've not seen it cause any problems and did several of them. The valves don't generate heat, and no air gets into the system.

 

[twistedtree]

Just curious...who makes the actual engine? Kubota? Yanmar? If you can track that down you might be able to buy the part through a different distribution channel where the engine is used for a different application. My 11KW Onan, for example, is powered by a Kubota diesel, and parts are available from many tractor dealers.

 

[Ski in NC]

The MDJ series was actually made by Onan. 1,2 and 4cyl. It started life as air cooled gasoline fueled, then adapted to diesel, then adapted to water cooling. I think the original design dates back to WW2 or thereabouts. Many units were made as portable military package units.

Early units used the big fat Prestolite (??) unit. Later versions used the thinner Woodward (??) unit. With a little adapting, the later version can be used. That link in post #23 has a few that look like they could be fitted.

I would not recommend putting a fuel valve in as a shutdown. With fuel flow into injection pump stopped, engine may continue to run by drawing fuel from the return line. It might not shut off when given an overheat or low oil P shutdown signal. The fuel solenoid trips the rack to no fuel, stops it right away.

 

[ksanders]

The MDJ series was actually made by Onan. 1,2 and 4cyl. It started life as air cooled gasoline fueled, then adapted to diesel, then adapted to water cooling. I think the original design dates back to WW2 or thereabouts. Many units were made as portable military package units.

Early units used the big fat Prestolite (??) unit. Later versions used the thinner Woodward (??) unit. With a little adapting, the later version can be used. That link in post #23 has a few that look like they could be fitted.

I would not recommend putting a fuel valve in as a shutdown. With fuel flow into injection pump stopped, engine may continue to run by drawing fuel from the return line. It might not shut off when given an overheat or low oil P shutdown signal. The fuel solenoid trips the rack to no fuel, stops it right away.

You got it right as far as the J series engines. They were great engines that were adapted for a variety of uses.

Please think about your comment regarding the suel sut off solenoid, and drawing fuel from the return line for a moment.

Remember that the fuel circuit goes from the injection pump to the injectors and then directly to the return line. That means that the return line is open from the injectors to the top of the tank.

Since the factory stock system takes the unit to zero throttle, it doesent change the return circuit.

I actually ran into the exact same issue that Steve is having now. I could not find a stock solenoid anywhere for a customers 7.5KW DJ unit. So, I tried it. I put a selonoid valve in the fuel line and it worked.