Perkins gen. shuts down after 10 min.

[LeoKa]

I have a Perkins 3.09 generator. If it sits for a while, it will start fine and run about 10-15 minutes. After this, it shuts down. If I try to start it again, it fires few times, but won't start.
I replaced all fuel lines. I bled the lines, checked the fuel at the pump, and at the injectors. They all look fine. I tightened up everything.
It seems that it runs out of fuel, or the pump cannot pickup enough from the tank. There is no fuel pump from the tank and the fuel filter. Only the original small pump is pushing the fuel to the injector pump.
The fuel tank is about 1/3 now, so I have apprx. 120 gallons of fuel there. The fuel pipe at the bottom of the tank is lower about a foot and half than the fuel pump on the engine. This pipe connects to a Racor filter, which is at the same level as the engine fuel pump.
The PO told me that the generator was running fine.
What am I missing?

 

[BIG CAT]

Have you checked output psi from the transfer pump? Also check the hand priming pump check valve if it has one. I've seen trash get stuck in the check valve causing similar issues. Also have you tried running it out of a bucket?

 

[LeoKa]

Have you checked output psi from the transfer pump? Also check the hand priming pump check valve if it has one. I've seen trash get stuck in the check valve causing similar issues. Also have you tried running it out of a bucket?

I don't have a transfer pump to the generator.
I will take apart the priming pump and clean it up.
I have not tried the bucket feed, yet.

 

[Russell Clifton]

Maybe not a fuel problem. Check your owners manual and see if there are any safety shutdown features on this unit. Perhaps it is overheating and a sensor is shutting it down.

 

[BIG CAT]

There should be a block mounted transfer pump on most Perkins. Right rear side if you're looking at the flywheel.

 

[LeoKa]

Maybe not a fuel problem. Check your owners manual and see if there are any safety shutdown features on this unit. Perhaps it is overheating and a sensor is shutting it down.

Nothing in the documentation I have says anything about shut down. I don't have the full service manual.

 

[FlyWright]

I don't have a transfer pump to the generator.
I will take apart the priming pump and clean it up.
I have not tried the bucket feed, yet.

I'd buy a cheap $10-20 fuel transfer pump and plumb it into the fuel line from the tank to the lift pump. Provide 12V power from a portable start battery pack. It should pump through the lift pump. Start and run the engine. If it runs normal, you've identified your problem and can decide if you want to replace the mechanical pump or add a 12V electric boost pump.

I hard wired two for fuel priming, transfer and boost in case the lift pumps fail. They remain OFF until needed. The guarded ON/OFF switch is in the ER by the Racors. If I ever make them permanent replacements for a failed lift pump, I'll power them through the start key switch.

 

[LeoKa]

There should be a block mounted transfer pump on most Perkins. Right rear side if you're looking at the flywheel.

I checked, no transfer pump.
If I follow the fuel, there is only the priming pump and hoses all the way to the injector.
This is a very old engine, from the early 80s.

 

[Ken E.]

Agree with Russell on looking into auto shutdowns. It happened to me this summer, in fact. Mine is a Northern Lights, 5kw. It would run for 10 minutes and shut down. The culprit was the internal coolant temp sensor. I couldn't find the problem, but a NL tech found it and fixed it.

 

[motion30]

I'm thinking if it is an auto shutdown, it will start it just will not run. It sounds like it does not wish to start

 

[Pack Mule]

Maybe check your fuel vent . My old sailboat had clogged vent and acted similar to what you’re describing.

 

[DavidM]

As others have noted it is probably a fuel problem or a shutdown issue. The shutdown issue is easier to diagnose. Just disconnect the leads to the temp sensor, then oil pressure sensor and see if it shuts down. Then replace the sensor that causes it.


You have replaced all of the fuel lines, replaced fuel filters, etc. But how about the fuel pickup pipe. Sometimes they have an inlet screen or check valve that plugs. I had a check valve at the top of the fuel tank plug with goop and after cleaning it out the engine ran fine.


David

 

[BIG CAT]

I checked, no transfer pump.
If I follow the fuel, there is only the priming pump and hoses all the way to the injector.
This is a very old engine, from the early 80s.

It could be integral to the injection pump.

 

[LeoKa]

As others have noted it is probably a fuel problem or a shutdown issue. The shutdown issue is easier to diagnose. Just disconnect the leads to the temp sensor, then oil pressure sensor and see if it shuts down. Then replace the sensor that causes it.


You have replaced all of the fuel lines, replaced fuel filters, etc. But how about the fuel pickup pipe. Sometimes they have an inlet screen or check valve that plugs. I had a check valve at the top of the fuel tank plug with goop and after cleaning it out the engine ran fine.


David

Good suggestions. I will do the sensor disconnect next time.

I thought about the tank pipe exit myself, but it is a messy job to take it apart and hard to get to it. Plus, there is a Racor dedicated to the generator between the tank pipe and the generator's fuel hose. The Racor is full and looks very clean. I just replaced the filter recently.

 

[LeoKa]

I hard wired two for fuel priming, transfer and boost in case the lift pumps fail. They remain OFF until needed. The guarded ON/OFF switch is in the ER by the Racors. If I ever make them permanent replacements for a failed lift pump, I'll power them through the start key switch.

I have a transfer pump between the port and starboard tanks. The main only feeds from the starboard tank, so I have to pump fuel over there sometimes.
The generator also feeds from the starboard tank, but it has its own pipe from the fuel manifold.
However, I do agree that a separate transfer pump for the generator is worth the investment. I would hardwire it to the turn on switch. First, I will try your suggestion, but it was my future goal anyway. The priming pump on the generator is almost two feet higher than the tank's pipe at the bottom. Instead of replacing the priming pump, the transfer pump is easier to manage.

 

[Bare Necessities]

Good morning and sorry about your trouble. I recently had a similar problem with my Kohler/Yanmar generator. It would run for about 12 minutes then shut down. To determine if it was fuel, air or other problem such as shut down sensor, I removed the engine filter after it quit. The engine fuel filter was empty. I could fill the fuel filter and it would run until filter was empty. I changed the Racor filter, checked connections/hose clamps but did not fix my problem. I suspected the engine mounted lift pump. I changed the lift pump but still did not fix my problem. Everyone I asked about it said it sounded like an air leak between the tank and lift pump. I used a vacuum pump connect at the lift pump and I could not pull a vacuum or fuel. That confirmed I had an open line leak somewhere. I blew on the line out of desperation and I could see a little seeping out of the Racor filter between the top part and the bottom part. I had not previously had it apart but I took it apart and put a new "O" ring between the top and bottom. Solved the problem. The old "O" ring did not look bad but it was hard. If you determine whether it is fuel or some other sensor would be my suggestion. I hope I made sense in my description of what I did. It was frustrating because where it was sucking air, there was no fuel leak until I blew on the line.

 

[psneeld]

What make and model injector pump?

 

[Bare Necessities]

Mine is a 1989 Yanmar Diesel model 1JHLT-K and I found one on eBay that looked like it so I contacted the seller and decided it would fit my engine. It did. It was listed as follows: New Fuel Lift Pump For Yanmar Marine Diesel Engine JH Series 4JH 4JH-TH for $28.99. You can google it and see a picture.
I left the new pump on after changing it, but it was not my problem. I would determine for sure if it is running out of fuel. If it has an engine mounted fuel filter you can run it till it quits and check to see if it is empty/dry. If it is, at least you should be safe in saying it is a fuel problem and not a sensor shutting it down. As I previously stated, my problem was an "O" ring between the Racor top and bottom creating an air leak that would not let my fuel pump draw fuel.

 

[Bare Necessities]

Sorry I thought the last post was a question in regard to my post.

 

[LeoKa]

I blew on the line out of desperation and I could see a little seeping out of the Racor filter between the top part and the bottom part. I had not previously had it apart but I took it apart and put a new "O" ring between the top and bottom. Solved the problem. The old "O" ring did not look bad but it was hard. If you determine whether it is fuel or some other sensor would be my suggestion. I hope I made sense in my description of what I did. It was frustrating because where it was sucking air, there was no fuel leak until I blew on the line.

I will certainly try this tonight. The reason I did not suspect the Racor, because I have changed the filter and O ring just about a month ago. I will get new O ring in and see what happens.
How did you blow the fuel line?

 

[DavidM]

Google "racor o-ring" and find articles and postings that describe how easy it is to reassemble the o-ring backwards, causing exactly the symptoms you have.


David

 

[Bare Necessities]

My trouble was not the "O" where you remove the top to replace the filter. The bottom half where you would take the bowl off is where mine was sucking air. In my case, I had not had any trouble and I had not even serviced the filter, so I really did not suspect the Racor. I did replace the filter just to eliminate it from being my problem but it did not fix it. I used a vacuum hand pump like you would bleed hydraulic brakes on your car. I hooked in the line coming from the Racor at the lift pump and I could not pull any vacuum, meaning the line had to be open/leaking some where between there and the tank or I would have pulled a vacuum and or fuel from the tank. I then thought if I blew on the line with my mouth, maybe I could hear a leaking somewhere. I didn't hear it, but I saw a little fuel seeping out where the two halves join. My Racor was mounted in a hard to get to place so I removed the entire housing so I could examine it better. The "O" ring between the upper and lower half is a little larger than the one for the filter cover. I cleaned the housing good, replaced the "O" ring, reinstalled, primed with fuel and she is running perfect. It may not be your problem but your symptoms sounds a lot like mine. Charlie

 

[Bare Necessities]

Once I got it all assembled, I used the vacuum hand pump to pull the fuel from the tank to prime the system so I didn't have to crank on it so long. I didn't have to bleed the injector lines. It ran a little ruff for a few seconds and smoothed out quickly.

 

[Simi 60]

Ill take a guess.
Oil and filter?

 

[LeoKa]

My trouble was not the "O" where you remove the top to replace the filter.Charlie

I will try this myself.
I did replace the filter and the upper O ring, but I did not remove the housing.

 

[LeoKa]

Google "racor o-ring" and find articles and postings that describe how easy it is to reassemble the o-ring backwards, causing exactly the symptoms you have.David

Are you talking about the upper O ring, which is on the top of the filter?
I did replace that. I had no idea that it can be installed backwards.

 

[Bare Necessities]

I was not aware the top "O" ring could be installed "backwards" either. It looked like a normal "O" ring to me.

 

[LeoKa]

Once I got it all assembled, I used the vacuum hand pump to pull the fuel from the tank to prime the system so I didn't have to crank on it so long. I didn't have to bleed the injector lines. It ran a little ruff for a few seconds and smoothed out quickly.

Tonight, I replaced the O ring again on the filter top and the small one on the tightening screw. I cleaned everything.
I tried to start the gen. but it won't start now. I used the priming pump on the engine and bled the line from the engine fuel filter. Still did not start.
I open the first injection line and cranked the engine. I could only see few bubbles but no solid fuel splash coming out to the injector.
How do I bleed the injection lines on the top of the engine? Or, is there a problem now with the injector unit?
This thing drives me nuts.

 

[Bare Necessities]

http://www.pbase.com/mainecruising/rebuilding_a_racor_


The link above may help. The "O"ring you have been changing is not the one I am talking about. If yours is like my Racor, there are 4 screws that fasten the bottom bowl housing to the top filter housing. I had not had mine apart, but that is where my air leak was at. Did you check to see if your engine mounted filter had fuel in it? I would determine if in fact it is quitting due to running out of fuel by checking to see if it is dry. If it is, fill it with fuel and replace it and see if it will crank. A hand vacuum pump hooked to your line at the engine lift pump should determine if it will pull fuel from the tank. If the hand vacuum will not pull fuel to the gen or build a vacuum, you have a leak somewhere between there and the tank. If it pulls a vacuum but not fuel, you have a blockage. You can call me if you would like to and if we are allowed to share phone numbers.

 

[BIG CAT]

Tonight, I replaced the O ring again on the filter top and the small one on the tightening screw. I cleaned everything.
I tried to start the gen. but it won't start now. I used the priming pump on the engine and bled the line from the engine fuel filter. Still did not start.
I open the first injection line and cranked the engine. I could only see few bubbles but no solid fuel splash coming out to the injector.
How do I bleed the injection lines on the top of the engine? Or, is there a problem now with the injector unit?
This thing drives me nuts.

Loosen the injection line nut where it connects to the injectors then crank it over till you see steady fuel without bubbles then tighten the down.