Westerbeke Slowly Dying

[clynn]

I have an 8k Westerbeke generator on my new to me boat. It starts and runs fine for about 5 minutes, then slowly starts to die. It will not start back up right away, but will after a few minutes. I've changed the raycor and fuel filter on the genny. It really seems like a lack of fuel, but I'm not sure where else to look besides the two filters. Anyone have and solved a similar issue?

Thanks for any thoughts or suggestions.

 

[Xsbank]

My failure (like that one) was a bad fuel pump. Bought an aftermarket pump (Walbro), installed and it ran fine after that.

 

[clynn]

Update: I can keep it running by manually pushing the throttle. Still thinking fuel pump?

 

[Aquabelle]

Air in fuel supply line?

 

[clynn]

Correction: I held open the fuel run solenoid, which seems to act like a throttle, but I'm learning as I go tonight.

 

[BruceK]

Correction: I held open the fuel run solenoid, which seems to act like a throttle, but I'm learning as I go tonight.

That`s new info, is it not holding in?
On an Onan, the solenoid has 2 "holds", the initial one to zap it across, and a second less powerful one to hold it there until shutdown. It shouldn`t operate as a throttle, it should be on, or off. If playing with it achieves something that is not happening, suspect the solenoid.
[Retired lawyers give really good mechanical advice, not. It`s just I`ve been through solenoid issues.]

 

[Pack Mule]

Sounds like a weak solenoid . Had to replace mine .

 

[clynn]

Pack Mule, do you happen to know if Dover Marine or someone else in the area carries those? We are picking up a Paris Landing buddy this afternoon on Lake Barkley and he may be able to grab us a spare.

 

[Bay Pelican]

12 volt solenoids come in at least 2 mounting options, one with a wings coming out each side of the cylinder and one with a right angled mounting plates. Westerbekes take the winged mounting. Over the years I have been shipped the wrong mounting plate. Not a problem for me as my Yanmar uses the right angled mounting plate

 

[Pack Mule]

Pack Mule, do you happen to know if Dover Marine or someone else in the area carries those? We are picking up a Paris Landing buddy this afternoon on Lake Barkley and he may be able to grab us a spare.

No not sure . Sometimes you can take them apart, clean and put back together for some more life . I ordered mine from deisel specialist out of Baton Rouge .

 

[Xsbank]

For the record, there is no "throttle" on a Diesel engine, only a fuel control lever.

 

[Ski in NC]

So does the solenoid/lever release as it bogs down, or does the lever stay put until it stalls? Big difference in troubleshooting.

 

[BobH]

For the record, there is no "throttle" on a Diesel engine, only a fuel control lever.

throt·tle
ˈTHrädl/
noun
noun: throttle; plural noun: throttles

1. 1.
   a device controlling the flow of fuel or power to an engine.
   
   
   
   
   

 

[Xsbank]

The throttle controls the air flow and the fuel flow is controlled by the air flow. That's how gas engines work.
Diesel engine's intake is a pipe with no moving restrictions, only a control that adjusts the injection pump and allows more or less fuel. Ergo bingo, no throttle on a Diesel engine.

 

[BobH]

Read the definition: "a device controlling the flow of fuel ". Or have somebody read it to you.

 

[Ski in NC]

Who ever wrote that definition is not likely an engineer, and it is an engineering term. "Throttle" originated to control steam engines, a valve in the steam admission line. Close or choke down the throttle, and it reduces power output of the steam engine.

Next came gasoline engines, and the throttle controlled the flow of air/fuel mix. Similar to steam engine, valve closes down on the admission flow.

Throttle a screaming kid, slows them down too. Not considered polite nowadays!!! Again, restricting admission flow, this time it is air.

Diesels are different. No throttling going on. Lever is "speed control lever" or "governor control lever" or "power control lever" or "fuel control lever" or a bunch of others. But those are too many words, too inconvenient.

Throttle in regards to diesels is technically incorrect, but it is widely used and even accepted amongst engineers.

But engineers sitting around the table discussing a governor design, no one will say "throttle".

Kind of like the "motor" and "engine" debate!!!

 

[BobH]

Second part of the definition: "controlling the flow of fuel or power to an engine". In a gas engine the throttle controls the air flow, in a diesel engine the "throttle" controls the fuel flow, in a steam engine it controls the steam flow. Same difference, they all control the power.


I guess I didn't realize this was a forum for engineers, although I was one before deciding software was an easier way to make money, no obvious jumpers on a circuit board. But I have spent a fair amount of time in engine rooms of steam powered ships so I do know what a throttle really is. I guess that really dates me, doesn't it.

 

[hmason]

Disconnect the wires to the solenoid. Then run wires directly from your battery terminals to the solenoid terminals, positive to positive and negative to negative. When you complete the connection, the solenoid plunger should snap in and stay there. If it doesn't the solenoid is bad and you have a different problem. Check all connections to temp and oil pressure sensors. If that doesn't solve it, the circuit board is suspect. Good luck, Howard

 

[clynn]

Thanks Howard, I'll run that test today. I found a used spare in the box 'o parts, so i'll test both and see how it goes.

Just so I'm clear, it should only be open or closed, right?

 

[hmason]

Right.

 

[Duvie]

Dies slowly

The original post stated that the engine dies slowly. I think a bad solenoid would tend to cause a quick shut down but I could be wrong. I have a Westerbeke 20B Two and was having a similar slowing down/shutting down of the engine. There is an oil pressure switch tied in series with the fuel pump. If the oil switch is bad or you have extremely low oil pressure the power to the fuel pump will be cut off but the engine in my set up was still able to get minimal fuel through the system and run poorly. A quick test for this is to hit the glow plug switch while the engine is running poorly. The power from the glow plug switch bypasses the oil switch for start up purposes. If you hit the glow plug switch while the engine is running poorly it will quickly recover if the problem is the oil switch. I believe the 8 kW generator is wired in the same way.

 

[stubones99]

Ski, diesels happened before gasoline engines did...

 

[siestakey]

I have the 8K westerbeke now it is virtually brand new with al the parts i parts I have replaced including the solenoid

when mine went bad it would start and run then when I put a load on it would die within a minute

 

[RickB]

Ski, diesels happened before gasoline engines did...

Siegfried Marcus just rolled over in his grave.

 

[stubones99]

Sorry to all... Wikipedia says Diesel happened around 1900, while gas engines (of all types) happened starting around 1850's with many innovations leading to more reliable ones on about 1870's...
Stu

 

[clynn]

Started the generator to do Duvie's test of hitting the preheat switch when it stared to fail, but 20 minutes later it was still running like a champ. Aggravating when you can't get a symptom to reoccurs on demand... I appreciate the feedback and will attempt to replicate the issue tomorrow and post an update.

 

[BruceK]

... I found a used spare in the box 'o parts, so i'll test both and see how it goes.

If the "used spare" is a solenoid, I bet you find it was removed because it was cactus. Onan manual says if they play up, replace. I know they would say that, and why, but experience says they are right.

 

[clynn]

Update:

Ran the generator and it began to die as expected. Held the Preheat switch as the RPM's dropped. The result was not a return to normal operating RPM's, but it kept running at the lowered rate for slightly longer.

I also tested the seemingly used spare in the box and got no result.

I checked the fuel solenoid after it died an it was red hot. The generator will not start right back up after it dies and I had assumed it was lacking fuel. I now believe that the solenoid is overheating and it only starts back once it cools off. I'll be ordering the new part today and will update the thread in a few weeks once I'm able to make it back to the boat.

 

[psneeld]

if that doesn't fix it...my 8kw Westerbeke (1989 vintage) genset had the exact same symptoms...turned out to be a really bad connector on the exhaust overtemp safety. I too started trouble shooting the fuel pump based on other threads....even bough a new pump...but figured I needed a spare and could always jury rig it to the main if in a spot.


I really thought it may be the fuel pump as when I would check the filter...the housing would be empty...but the way my auto shutdown system works...it prevents juice getting to the fuel pump somehow...need to look into that as I hope that is not the only way it shuts it down.


new connectors and back in business....well it ran for an hour, high load with no issues and it hadn't done that for the previous 8 attempts.


if I have a problem again, I'll be checking my solenoid...but mine seemed ok from the beginning of my problems.

 

[Ski in NC]

If solenoid cannot bottom out when energized, it will overheat. Make sure there is a little slop in linkage when retracted fully.