Yanmar 2QM15 starting problem

[mystery117]

I had the fuel tank go bad on me and the fuel filters were all gummed with the sludge from the tank. I had been motoring for about 4 days and don't know how long the problem had been developing. When the engine started to starve for fuel I quickly checked the filter, drained it and tried to restart the engine. When it wouldn't fire up I delved deeper and found the clogged filters and then the filthy tank. I've since changed out the tank (the old one started leaking after I cleaned it) got all the filters changed but can't get the ole girl to fire up. I've bleed the fuel line as far as the venting screw above the small filter on the engine. I've tried loosening the fuel line at the injector and cranking to bleed the system further but I've not had any luck. Will I have to tear down the fuel injectors and clean it all out? I've not done this so I'm a little wary.

 

[woodster]

try bleeding the fuel lines from the injector pump to the injectors and from the small filter to the pump when all the bubbles are gone you should be able to fire it up...obtw dont run the starter motor too long at a time ....two things could happen here 1 you could flood the exaughts manifold with raw water (ask me how i know) and get it in the cylinders and you also 2 could burn up your starter ...theses things should start on very little starter action and while you are bleeding the fuel lines make sure your decompression levers are pulled up to releave the cylinder compression and you may also when trying to restart the engine set it at 3/4 throttle they love this when starting cold...... no eather or starting fluid ...you could blow a gasket or pistion and the little engine will become an addic for eather ...then it will be off to rehab for sure...

regards

woody

 

[mystery117]

OK, here's the follow up. After attempting to bleed the system several times and cranking repeatedly for several minutes overall - no fuel coming out at the injectors.

I removed the injector pump and found it needed to be rebuilt. Done. I elected to replace the injectors at the same time since the pump showed excessive wear, probably from the bad fuel running through it.

I've got it all back together, sure I've got it in right, but no fuel is getting past the injector pump. Grrrrr... no, the shut off is not engaged. Yes, the fuel is on, and I have used the lift pump to get fuel up to the engine mounted fuel filter.

Ideas? Suggestions?

 

[woodster]

OK, here's the follow up. After attempting to bleed the system several times and cranking repeatedly for several minutes overall - no fuel coming out at the injectors.

I removed the injector pump and found it needed to be rebuilt. Done. I elected to replace the injectors at the same time since the pump showed excessive wear, probably from the bad fuel running through it.

I've got it all back together, sure I've got it in right, but no fuel is getting past the injector pump. Grrrrr... no, the shut off is not engaged. Yes, the fuel is on, and I have used the lift pump to get fuel up to the engine mounted fuel filter.

Ideas? Suggestions?

you may have a clogged fuel line coming from the filter to the injector pump...take it off and see if you can get fuel to flow through it ...also check the fasteners that connect the fuel line to the filter and the pump to see if there ports are clear and flowing...better yet just bleed the line at the fuel filter to the injector pump and see if fuel flows out..if not that may be your problem...take theses fuel bleeding procedures one step at a time until you get fuel at all bleeder screws...oh one other thing make sure you have the filter full of fuel and a good strainer filter in it ...i assume you did refill the filter on the engine when reinstalling every thing....

hope this helps

regards

woody

 

[mystery117]

The line from the fuel filter to the injector pump is clean, I blew through it before installation to ensure it was not clogged. The bleeder screw on the filter produces fuel with a good stream while pressing the lift pump leaver. The filter was filled when replaced and reinstalled.

 

[woodster]

do you get fuel on the othere end of the fuel line coming from the filter to the pump.....

regards

woody

 

[kloudie1]

Mystery, back off the high pressure connection at the injector and manually pump the lift pump until fuel comes out at the injector. Yo may have to rotate the engine a little to get the lift pump drive cam clear of the operating lever so you can pump it with a finger. Do both injectors. Then tighten the high pressure connection and open the return line connection on top of the injector and manually pump until fuel comes out there.. That should do it. Now it should fire.. (compression release not on)

 

[Bill Roosa]

there is a lever on the mechanical fuel pump so you don't have to crank the engine and fill it with water.

 

[woodster]

Mystery, back off the high pressure connection at the injector and manually pump the lift pump until fuel comes out at the injector. Yo may have to rotate the engine a little to get the lift pump drive cam clear of the operating lever so you can pump it with a finger. Do both injectors. Then tighten the high pressure connection and open the return line connection on top of the injector and manually pump until fuel comes out there.. That should do it. Now it should fire.. (compression release not on)

i dont think there is a fuel return line on that engine ...i know my old one didnt have one...everything else you stated was the way i learned to do it

regrds

woody

 

[FrogHenry]

How I bleed my 2qm20

This is how I bleed my 2QM20: I start at the Primary Filter (Racor,) next bleed the Secondary Filter, next bleed the Injector Pump (10mm screw), next bleed the closest injector and then bleed the farthest injector. I have help as I have a fuel pump installed in the line for the Dickinson heater. I use absorbent towels as I go. Being new to the boat and engine I have bled it dry many times for one reason or another and just moved the heater and fuel filter from the Port side to the Starboard side. Lot of bleeding and messing with fuel lines.Good luck.

 

[kloudie1]

Woodster.. The return line is the top fitting (as opposed to the side, high pressure fitting) on the injector. On that engine, it returns to the filter housing instead of the fuel tank, as most do.

 

[fredr]

Mystery, you DO have fuel to the secondary filter (just before the INJECTION pump) And all the air is bled out at the secondary filter from the top bleeder screw. Yes?
Loosen the fuel line (or the bleed screw) on the INJECTION pump, this is the line that comes from the secondary fuel filter to feed the INJECTION pump.
Pump the supply pump lever until solid fuel comes out of the line you loosened on the INJECTION pump, no air at all. Tighten the line (bleeder) at the INJECTION pump.
Now loosen the line nuts on the nozzles, (Not the at the INJECTION pump) 1/2 turn
Crank the engine.
When fuel spits out at the nozzles, tighten nuts you loosened.
Did you put the same timing shims UNDER the injection pump?
Did you get the injection pump fuel control rack into the governor lever when you put the pump on?

 

[bugaloo]

Make sure the fuel line from the secondary filter to the injection pump is good and no air leaks, had this happen and the injection pump was drawing air and the engine would not crank. also shut the seacock to the engine off while cranking and you will not fill your engine with water.

 

[mystery117]

Final update: I work 12 hr shifts Friday to Sunday so got back to the boat yesterday. Removed and replaced the small filter on the engine and then repeated the bleeding procedure. It started... but now I'm seeing a leak on the high pressure line at the injector pump. Local supplier can only obtain the high pressure line for cylinder #1, said that #2 is no longer manufactured. Anyone know where I can get a replacement for #2?
O, and thanks for all the input. Kept me going to and successful conclusion.
Happy holidays and Happy New Year.

 

[rufus1138]

don't give that guy any more of your money, find a parts house that knows what a yanmar is and give them your business instead. nothing gets me out of a businesses pocket faster than ignorance.

 

[bugaloo]

Try Torrensen marine.com They have anything I have needed for a 2qm15 in the past.

 

[mystery117]

Torresen Online Store is now TOAD Marine Supply. I have a parts manual and found the part number for fuel lines A and B, as listed in the parts book. TOAD only has line A and line B does not exist on their site.

 

[eaststorm]

I had a fuel delivery issue with my newly installed Yanmar 4jh4ae.....check your flexible fuel lines where they attach to any connector, nipple, barb, etc. Turns out there is now a special 'liner' in some fuel lines and if this inner liner gets separated or pulls away and gets folded over from the inner wall of the hose, it will block the flow of fuel or limit it severely. It took two trips from the service tech, changing fuel pumps and lots of aggrivation until I figured this out.

 

[fredr]

Some Fuel Injection shops can make a line for you. Call around to diesel injection rebuild facilities.

fred