My Official OM617 Toyota Pickup Repower Thread - Page 30 - PeachParts Mercedes-Benz Forum

OM617YOTA · #**436** 05-23-2014, 01:05 AM

Got the primer pump swapped to the gen-yoo-wine Bosch pump. Symptoms improved by ~90%. Still a little bobble in the first three minutes of idle if I let it sit overnight, and I can't visibly see any air in the return lines anymore. Definitely on the right track. This weekend I plan to rebuild the lift pump and check on a couple other things.

Thanks all.

Cadin · #**437** 05-23-2014, 01:10 AM

Yaaay! Congratulations!
(BTW, I just grabbed another motor from P&P today!...)

OM617YOTA · #**438** 05-23-2014, 09:10 AM

(Nice! Isn't one of the JY's in the area doing a half-off sale this weekend?)

Cadin · #**439** 05-23-2014, 02:57 PM

(Yepper, all of the Pick N Pulls; Every Memorial Day and Labor Day.)

OM617YOTA · #**440** 05-26-2014, 08:47 PM

Another update.

I replaced the hard plastic fuel lines leading from the lift pump to the spin on filter, and from the spin on filter to the IP with standard fuel line and hose clamps. The bottom of the banjo bolt that connects to the IP was wet with clean fuel and so was the bottom of the lift pump, and one of the hard plastic lines looked melted(see photo). Edit: The photo looks dirty, that's actually pitted and melted. After replacing the clear lines, I have no more fuel wetness and as far as I can tell I have no more air in the system.

I pulled the fuel line from the surge tank to the lift pump off, stuck it in a coffee can, and turned on the electric in-tank pump. 3lb coffee can half full of fuel in less than 30 seconds. The lift pump is getting enough fuel.

I still have the miss, and some gnarly top end noise. Yanked the valve cover and re-verified that all my valves are set within spec.

I took another video and posted the link below. I would very much welcome any suggestions anyone has. I am out of ideas, my next step is taking it to a Mercedes shop for diagnoses.

Yota diesel irregular rattling - YouTube

Thanks everyone.

mach4 · #**441** 05-26-2014, 09:55 PM

Quote:

Originally Posted by OM617YOTA

I pulled the fuel line from the surge tank to the lift pump off, stuck it in a coffee can, and turned on the electric in-tank pump. 3lb coffee can half full of fuel in less than 30 seconds. The lift pump is getting enough fuel.

That might be part of your problem actually. The lift pump is designed to pull fuel directly from the tank on its own. It doesn't need a "boost pump", and if you do have one it should be a low flow 4psi one. Do a search on eBay for "electric fuel pump low pressure" and you'll find a bunch.

You could be pushing up to 60psi potentially with the in-tank pump, depending on the pump you've got and whether it is a fuel injection pump or something else and whether there is a pressure regulator and what it's set for. You might want to rethink your fuel system configuration.

Stretch · #**442** 05-27-2014, 02:04 AM

Why did you install the additional pump?

Nasty shake going on there - like an out of balance vibration

OM617YOTA · #**443** 05-27-2014, 09:18 AM

Thanks for the ideas. The "extra" pump is the stock in-tank pump from when the Yota was a gasser. It feeds to a surge tank which vents straight back to the fuel tank, and the only pressure there would be whatever is created in venting that fuel back to the tank. This system worked great for ~5k miles, and this miss only came about after I installed the rebuilt injectors and reset the injection timing. That shaking is from the miss.

My main concern is the top end noise, any ideas there? I've tried killing individual injectors, the noise stays put. I've tried the screwdriver-as-stethoscope method to pinpoint the noise, no luck. Any other tests you guys can think of, I'm happy to run.

Thank you!

mach4 · #**444** 05-27-2014, 09:31 AM

Quote:

Originally Posted by OM617YOTA

The "extra" pump is the stock in-tank pump from when the Yota was a gasser. It feeds to a surge tank which vents straight back to the fuel tank, and the only pressure there would be whatever is created in venting that fuel back to the tank. This system worked great for ~5k miles, and this miss only came about after I installed the rebuilt injectors and reset the injection timing.

That works. I assumed that the stock pump was feeding the lift pump directly. Unless there was some kind of restriction in the "vent" line there should be no appreciable pressure.

funola · #**445** 05-27-2014, 09:53 AM

Quote:

Originally Posted by OM617YOTA

........ and this miss only came about after I installed the rebuilt injectors and reset the injection timing. That shaking is from the miss.

My main concern is the top end noise, any ideas there? I've tried killing individual injectors, the noise stays put. I've tried the screwdriver-as-stethoscope method to pinpoint the noise, no luck. Any other tests you guys can think of, I'm happy to run.

Thank you!

You have to go back and scrutinize the rebuilt inj and timing. Did you rebuild them? Did you use new heat shields (facing the right direction)?

OM617YOTA · #**446** 05-27-2014, 10:11 AM

Thanks folks.

The injectors were rebuilt by our resident injector expert here on the forum. Yes I used new heat shields, and yes facing the correct direction. Soapy water test shows no leaks there. Pretty confident the injectors are fine.

Any ideas on that top end noise? Wondering if I got the timing off, or if it moved.

funola · #**447** 05-27-2014, 10:19 AM

Did the miss come after the rebuilt injectors or after the timing? Assuming you did'n't do the injectors and the timing at the same time?

I say take out the injectors and get them pop tested. They could have been damaged in shipping, or dropped, damaging a pintle.

OM617YOTA · #**448** 05-27-2014, 10:24 AM

I installed the rebuilt injectors and all seemed well, other than some odd noise. Reset timing and got the miss and then increasingly more noise. Replacing the hand primer pump with a genuine Bosch primer helped the miss considerably, as did replacing the fuel lines. The top end noise has gotten progressively worse, and the miss is still there.

greazzer · #**449** 05-27-2014, 10:39 AM

Those injectors are spot on. The noise is normal. They will have the "extra" noise for 200-500 miles and it should go away. There should be a clang or chatter until they settle in. If you hear a metalic like clang, then that's air.

funola · #**450** 05-27-2014, 10:40 AM

Quote:

Originally Posted by OM617YOTA

I installed the rebuilt injectors and all seemed well, other than some odd noise. Reset timing and got the miss and then increasingly more noise. Replacing the hand primer pump with a genuine Bosch primer helped the miss considerably, as did replacing the fuel lines. The top end noise has gotten progressively worse, and the miss is still there.

Was the odd noise different than the miss? From what I've read, introducing debris in the delivery valve is a common problem when doing drip timing.