Newb with a Yanmar question

[mighty midjet]

Hi . I've been strolling this site for a while and have found it quite useful, especially for getting my Hatz up and going.

I have a new toy now that I need some help on. I just got a Yanmar diesel powered generator that won't run. the fuel tank wasn't attached when I got it and didn't come any brackets to mount it so I just used some bailing wire to hang it from the cage. I used a piece of clear fuel line I had laying around to run from the tank to the injection pump. Cracked the line at the injector and turned it over until fuel was coming out then bolted it back down. Followed the directions on the tank for starting but after 20 minutes of pulling on the starter it just would not start. I gave it a little squirt of ether even though I rally hate doing that to diesels. It sputtered up but died right away. Gave it a little more and tried it again. When it runs on the ether it blows air up the fuel line and into the tank. Blows all the fuel out of the line and with the cap off of the tank I can see bubbles. Is there something I'm missing or does this mean I have a bad injector or a bad pump, maybe a bad check valve? All help is greatly appreciated Its a L70ae model

 

[Speddmon]

Welcome aboard. I'm sure someone on here will come along and help answer your question. This is just for your reference to store away for future use.

Posting questions in the appropriate section of the board will get you much better and faster responses. It would have been much better for you to post this in the Aux. Equipment forum as many people just scan a section of the board that they are interested in and not the whole board. I will move this thread for you and with any luck you'll get the help you need.

 

[Gunzy]

mighty midjet, I live in Roy and have one of those MEP016 with the Yanmar conversion. If you need to look at one you can call me at 801-726-6864 and come by to see it. I have had mine running and started it 2 of 3 available ways. If this will help you call.

 

[storeman]

It would seem that you have no check valve in the supply line and may not have connected a fuel return line from the injectors.
Jerry

 

[Isaac-1]

Did you bleed the injector?

 

[mighty midjet]

mighty midjet, I live in Roy and have one of those MEP016 with the Yanmar conversion. If you need to look at one you can call me at 801-726-6864 and come by to see it. I have had mine running and started it 2 of 3 available ways. If this will help you call.

Thank you!! I will Probably call you on Monday

It would seem that you have no check valve in the supply line and may not have connected a fuel return line from the injectors.

I do have a check valve. I pulled it off the pump, disassembled it, cleaned a little rust out of it, and reinstalled it. The return line has nothing coming from it. no fuel or air.

Did you bleed the injector?

I pulled the line at the injector but I did not pull the injector.

 

[bigboy44]

There is something better than either, some gas on a rag! I will not use either unless that is all I have and I have to get something started right away. i think diesels get addicted to it like a crack head does to crack! My .

 

[mighty midjet]

Ok so I pulled the injector and bolted it to the hard line. No fuel is coming out of it. I doesn't matter how much I pull on the starter. I reinstalled the injector after pulling it apart and cleaning it. Leaving the hard line unhooked and letting it putter on ether I can see little puffs of black smoke coming out of the injector. I this normal? Is that why there is a check valve?

 

[Carlo]

It would seem that you have no check valve in the supply line and may not have connected a fuel return line from the injectors.
Jerry

jerry I think you nailed this one. I agree with you he's got them backwards.

 

[Kloakndagr]

Wow, I lived in Roy for a few years. I loved Sills Cafe, Maddox, Crown Burger and the Burger Bar. Best neighbors I ever had, and we weren't Morman. Excellent place to raise a family, sadly Uncle Sam thought it a good idea to send me to Eglin AFB, Florida. That placed sucked!

 

[Isaac-1]

If this is a MEP-016D, why not hook some jumper cables to the starter and save your arm some pulling? It will crank on 12V even though it is a 24V starter

 

[RIrvin]

This may help. Good detail on Yanmar fuel system starts about page 170.View attachment Yanmar L70V Service-DETAILED Complete.pdf

 

[mighty midjet]

There is no starter on it.

 

[ETN550]

These can be very tough to bleed even when there is fuel coming out of the line at the injector there can be air in the system that compresses when the fuel line is hooked back up. Before you get into more teardown concentrate on the bleeding.

I pull the starter recoil and put a socket on the crankshaft and turn it with a 120 volt drill, not a cordless. Hold the compression release down and do not attempt to start it with the drill just bleed it. Spin it up to full speed on the drill and make sure it is in the right direction. While all this is going on rack the fuel lever to full fuel. Continue until for a 30 sec or more after a good amount of fuel is coming out.

If the delivery valve on top of the injection pump is what you are referring to as the check valve and if there is any rust inside then replace the whole pump. Rust is a problem and units with the fuel tank removed can have this issue as water is heavier than fuel and even one drop of water will find its way into the pump because the whole fuel system is gravity fed.

 

[mighty midjet]

That's a great idea! Hopefully the drill I have is fast enough. I know it has the torque.
There was rust in the valve but none of the components where rusty.

 

[Gunzy]

There is no starter on it.

Mine has a starter.

 

[mighty midjet]

This may help. Good detail on Yanmar fuel system starts about page 170.

Best manual I've seen yet. The only difference from mine and the book is the length of the fuel line feeding the pump.

 

[mighty midjet]

I used the drill to turn it over. I put a some oil in the cylinder through the injector hole then spun in it off and on for about 5 minutes. I didn't want to do it any longer than that, my drill was getting hot. Nothing came out of the injector. So is it safe to say that my pump is not creating enough pressure?

 

[ETN550]

Just to confirm when you did what you said you had the lever in the full fuel run position, right? The pump will not pump any fuel in the off position.

Most likely the pump is stuck or tight. The cam pushes the plunger up in the pump and then a spring returns it. When they get stuck the cam can push the plunger up once but the spring is not strong enough to return it.

I have not had one of those pumps apart but if it is like others you may be able to remove the line and then remove the next part on top of the pump which should be the delivery valve. Keep it very clean and make sure the disc is not marred at all. With the valve out of the way you should be able to see the top of the plunger. It may be possible to free it up by gently tapping it down with a punch and SMALL hammer. Then put some penetrating oil on it and rotate the engine to see if it comes back up. Continue with this process and many times they will free up. Or the pump can be removed and you can try to free it up on the bench. Just beware that the tolerances in the pump are extremely close and any dirt can damage it. It should be washed in clean fuel before it goes back in. If the pump cannot be freed up or if it is damaged or rusted then buy a new pump assembly.