Fuel Solenoid Problem..

Hi folks,

I have a Westerbeke diesel 7.7 KW genset and was told by a mechanic my fuel solenoid was bad. It wouldn't pull the throttle all the way back but it would lock in place with a little push. The battery was recharged and checked but he told me to get another solenoid which I did for $167 online.

While I waited 2 weeks for my first paycheck at West Marine to arrive and another week for the part, I was starting the generator which would barely idle, then I'd jump down and push in the solenoid. I was doing this twice a day just to keep the fridge cold and the batteries charged.

When the new solenoid arrived, I carefully replaced the old one and made sure all the wires were to the same terminals but it also wouldn't pull in over half way, identical to the "bad" one I'd replaced. I tried to start it twice and only briefly then called the mechanic who came over and checked all the wiring and the adjustment. He guessed the battery was low and told me to run the generator for a while and charge the battery then try it again. To start it he had to nudge it in all the way when I pressed the fuel pump switch. I ran it for 3 hours and enjoyed the air conditioning but was skeptical about this mechanic's expertise as he seemed pretty unsure of his diagnosis as the new one was acting the same as the old one.

After I shut it off I tried to start it again immediately and the solenoid acted the same as it had before and I was unable to start the generator. I wasn't surprised but it was late and I went to bed. Yesterday before I left for work I tried to start it as I had with the old one where it would start but just barely running at low idle until I was able to jump down and push in the solenoid but it wouldn't idle long enough for me to do that. I didn't have time to fool with it and went to work. When I got back from work I tried it again with no luck. I then realized I had a piece of molding that was just long enough to reach from the starting panel down to the arm of the throttle and I started the generator and pushed in the solenoid with the stick. I checked the voltage and it was adjusted a little low so I ran one air conditioner and the fridge and a few other things and the voltage was right at 120 volts on the meter on my panel. The gage on the Westerbeke panel wasn't showing any output at all and I tapped on the glass thinking it may be a stuck gauge but it didn't move. Everything else was normal so I decided to let it run to get the batteries back up as I have no solar panels. Also, my house batteries are very bad and need to be replaced but I don't have the money yet. 20 minutes later the generator shut off automatically and i jumped up to see what was wrong and that's when I smelled the fried solenoid.

Went to get on the computer and realized my computer had gotten dripped on through an open hatch in a brief squall while I was at work and it would start but I couldn't use the mouse! I messed with it for 3 hours before finally being able to get everything working correctly but the 3 beers I had in the process put me to sleep.

Today's my day off and I've got no generator, my new 8D starting battery I put in two months ago is "aiding," the ailing house batteries for now but I've lost all confidence in my new "mechanic," and desperate to know where to go from here. My boss at WM has a list of reputable mechanics but they're all scheduled out for at least a week.

I still don't understand what happenend and why so I'm hesitant to put the old one back in for fear of frying it too.

Any help or suggestions would be greatly appreciated. Oh, and by the way, while I was waiting on the solenoid I decided to replace my hoses off the exhaust elbows on my mains because they looked very bad. I just brought the new hose from work but haven't put them on the nearly rusted out old exhaust elbows so I'm dead in the water at the moment.

This all snowballed as I lost a substantial source of income last year and have been squeeking by on very litlle.

Thanks again!

I'm also on a mooring ball!!!!!!!!!!!!!!!!!

I would check the voltage to the solenoid with the preheat switch activated.
If voltage is low, it maybe because of green wire somewhere in the circuit.
The solenoid needs to pull in completely or it will overheat. I know this because I worked at a company that made solenoid valves (same principle).
I also have a 4.4 Westerbeke with probably the same solenoid. It has to be mounted such that it pulls all the way in. That "may" have been the reason your new one burned up????
You can check the old solenoid by putting 12 v (and ground) to it without the rod connected to the pump linkage (or on a bench, etc) it should pull all the way in if it's good.
Sometimes the bore or the plunger gets dirty or corroded a little and that amount of resistance will be enough to prevent the solenoid from pulling all the way in.
I had a hesitating solenoid and after cleaning it worked fine.

I couldn't stand to read your whole post- too much info, but your issue is clearly mechanical linkage and has nothing to do with the solenoid itself.

When the solenoid tries to pull in it stops partway because something mechanical is binding and won't let it easily go all of the way. When the solenoid is stopped partway the heavy coil that moves it is still engaged. It has to pull in all of the way to switch to the light, holding coil. The heavy coil will burn up if left on too long.

So find what is causing the binding, Work it out so that your solenoid always pulls in completely. Your problems will be solved.

David

The solenoid is a two coil solenoid and has an internal switch. There is an instruction that goes along with the solenoid that requires the solenoid be adjusted in its mounting position otherwise the second coil is not switched and you run the risk of burning up the first coil because it is not meant to be powered all the time. The second coil draws a lot less power and simply holds the solenoid rather than move it. In my opinion you need to get the adjustment instruction and follow it.

"Went to get on the computer and realized my computer had gotten dripped on through an open hatch in a brief squall while I was at work"

You are ready for a fully automatic rain hatch closer.

Cut a wood triangle about 1 1/2 inches on the sq side/

Glue it into a corner of the hatch away from the hinges.

Should you have the best hatch in the world, a Goyot , make a pair,

Drill a hole small enough in the installed triangle for a chop stick to fall (just) thru.

On leaving the boat install an Aspirin over the hole and stick the chopstick up to prop the hatch open, while resting on the aspirin.

Done! When it rains , it drops shut.

You need to get an electrician as your mechanic clearly doesn't get it. These solenoids have two positions: they retract initially to start using a high current; and then they "relax" into a much lower current-draw position to maintain fuel flow. The linkages need to be correctly adjusted so that the solenoid can both fully retract initially and then move into the relaxed, low current draw position. It can be fiddly if you haven't done this before and often, the linkages that worked for the original solenoid need to be modified a little to work with a new solenoid. If all is not adjusted right, the solenoid remains in high-draw mode and burns out. Find a marine electrician who knows what they're doing: 30min job if you have all laid out/opened up for him

Instructions for fuel solenoid

Westerbeke came out with a update several years ago about running a larger gauge wire to the fuel solenoid on the BT 8.0 gen set. This may also be the fix for your problem and your lack of faith in the mechanic is well deserved. I'll 2nd that the problem is probably low voltage at the solenoid, be sure the solenoid linkage is adjusted correctly to the proper rpm so that the AC voltage output is correct, you can use a photo tach to adjust the linkage.

Bigfish

"Failure of the solenoid plunger to bottom in the solenoid will result in a failed solenoid." If the generator starts and the alternator is working the voltage will be enough. If the solenoid does not pull in it will burn up the pull in coil. Once this happens all you have left is the holding coil and it is not enough to pull the solenoid in. After you assist the solenoid the hold in coil will hold it. What you have been describing fits this problem exactly.

Bigfish ,
obthomas and these guys know what they are talking about . I had the exact same problem with the same generator and they walked me thru it also.

For the time being, could he tie off the linkage to the full run position, start and run the gen-set and then untie the linkage when shutting down the gen-set?

Sort of a less convenient stand in for the solenoid.

This only as a work around temporarily, I ask as this could happen while cruising and getting a repair may be a bit away.

SCOTTEDAVIS said:

For the time being, could he tie off the linkage to the full run position, start and run the gen-set and then untie the linkage when shutting down the gen-set?

Sort of a less convenient stand in for the solenoid.

This only as a work around temporarily, I ask as this could happen while cruising and getting a repair may be a bit away.

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Yes. Its what he is doing now. Once the pull in coil is destroyed you can't really do any more damage.

Would tying if off disable the auto shutdown features?

psneeld said:

Would tying if off disable the auto shutdown features?

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Yes. That would be a problem.

psneeld said:

Would tying if off disable the auto shutdown features?

Click to expand...

Good point!

Running in this manner would be only advisable under close supervision and then only as a temporary situation for sure. Makes a case for my thoughts on a water flow and exhaust temp. warning panel (another thread) to include the gen-set.

Good info. thanks all.