How to bleed the fuel system on a Peugeot/Lehman?

[REO]

I thought I knew how to bleed a fuel system since a previous boat had a perkins 4236. Hard to bleed engine.

I recently replaced the mechanical pump with an electric. Ran the pump to fill the disconnected line to the filter. Ran the pump to be sure the filter was full and the out put from the filter was clear. Ran the pump to be sure fuel was coming out of the end of the line that goes into the high pressure pump. Loosened the 8mm bleeder screw on the side of the high pressure pump. Got a nice clear, strong flow.
When I loosen the nuts on top of the injectors nothing comes out. Nothing comes out of the fuel lines where they connect to the high pressure pump. Is there a bleeder that I don't know about?

[denchen]

Not sure what type of injector pump you have but on mine I also have to bleed from one of the output banjos whilst cranking. Ensure you have full throttle whilst cranking.

[REO]

Thanks Drenchen
I am going back to try again.
I did try to get fuel from the banjoe output connection. But, I may not have had it at full throttle.
Maybe that's why I get no fuel from that connection. We will see soon.

[denchen]

If all fails you might try taking a top banjoo off and back fill the pump with diesel using say an oil can.

[denchen]

Just had another thought, if it has electric stop, check when key is on, there is 12v to the stop solenoid, you can sometimes hear a click.

[smacksman]

I'm in the UK and away from the boat but I seem to remember there were two bleeds on the pump.
You won't get fuel at the injectors till the high pressure pump is working and some throttle. (personally I don't go full throttle). A two person job. Crank the engine with ignition on and electric fuel pump on and loosen fuel line joint at each injector in turn till fuel flows freely. She may well start on two cylinders. Take care bleeding the last two injectors in case you get diesel injected into your hands!
So much easier and safer and less battery drain on diesels with de-compression levers.
My stop solenoid on Free State doesn't work so I guess it defaults to 'always -on'. I rigged a Wallmart bicycle brake cable as a 'pull stop' - foolproof!

[REO]

I found the problem. When I was still getting no fuel out of the high pressure pump I decided to look at the fuel shut off switch. I traced the wire and found that it had come off the ignition switch when I put on the new wire for the electric fuel pump. Your guess was correct. The fuel was shut off at the pump. Thanks for helping me think it through. It kicked a few times and I still have some air in the lines, but I'm sure it will start now. I'm quitting now so I have time to wash the smell off. Thanks again for the help.

[smacksman]

Real mechanics put a dab of diesel behind each ear before going on a date. Drives the girls crazy! A legal high!!

[REO]

Still no fuel at the injectors.
I completely removed the bleeder screw on the side of the high pressure pump and there is clear fuel coming out both when the electric pump is on and when the engine is cranked. I completely removed the nuts on top of the injectors and there is a tiny puff of mostly air when the engine is turned over. Is there a second bleeder screw on the injector pump?
There is a screw with a lock nut at the top portion of the front of the pump (vertical surface). It is near the manual shut off valve handle and it is directly below a cast in arrow pointing forward and back (horizontal surface just above the screw).
I am very reluctant to start turning a screw that I don't know the function of. This one does not have a safety wire locking it in place. But it does not look like a bleeder screw.

[kerrye]

I'm not familiar with the Peugot but I know there are some tests you can perform on other diesels. For instance, on Mercedes diesels, when you pump the primer pump, once the air is gone it diverts the flow of fuel back into the return lines at the filter. Have you checked the return line on your system? Is there flow thru it with the electric pump on and engine cranked?

[REO]

The return lines come off the injector bodies and there is no fuel getting to that area, so no return fuel.

[sail149]

I was looking into the bleeding issue and was reading the posts on the site.
Do you have a copy of the Lehman maintenance manual?
Have you bleed the secondary fuel filter?
You should be getting fuel going out of the filter bypass back to the tank.
It shows you the 3 bleed points clearly on the roto-diesel pump and a clear fuel line diagram so you can work your way down the lines to bleed each Union as you work you way from the feed pump.
If you don't have a copy it has details on how to bleed so this may be the way to go
The manual is on the site I think but I can scan pages of you need them
Warren

[sail149]

I checked the manual is on the site
viewtopic.php?f=63&t=3700
Page 24 onward on the PDF
Warren

[kerrye]

Here's a thread about the engine in general including other versions of the engine marinized by other companies. There's also someone on that forum who claims to know a lot about the engine.

http://www.ybw.com/forums/archive/index ... 69286.html

[smacksman]

There's hope for me yet! My brain still sort of works!
I said earlier in the thread that I thought there were two bleed screws on the pump!