Oil & Fuel Fuel Pump Timing Help??

[mark777]

Hey everyone,

On my YM1610D -

I was experiencing "White Smoke"...and it wasn't water. It was a hydraulic pump seal that blew and dumped 3+ quarts of hydraulic fluid in the crank case, hence the white smoke, as the tractor was trying to burn the combination of fluid, fuel and diluted engine oil. Not a problem as I pulled the pump, split it and replaced the seal and reinstalled the unit. New filters, fresh oil and topped off the hydraulic oil.

Now I have a problem, as I am way down on power (at least 50%), the exhaust smoke is black with unburnt fuel, and is the type that stings your eyes in an enclosed area. The engine RPM tries to run a constant RPM but will suddenly drop off (and sometimes stall) and fluctuates between 1800-2400 RPM with no load. Under a load, like dropping the box blade and engaging gravel is much worse...and it WILL stall.

My question is, Is it possible to accidentally disturb the fuel injection timing by R & I the hydraulic pump?? There are no marks on the hyd. pump gear to indicate any timing...but am I missing something? Has anyone experienced a problem like or similar to this?

Thanks for any help and feedback!

Mark

 

[bruce1966us]

As long as you didn't have the front timing cover off I don't see how the injection pump timing would be affected.

 

[YanmarFever]

Hi Mark
I have had that happen before to a 1610 we had here. I just changed out the inj. pump and it was fixed. However when you pulled the pump off did you see that small rod that connects inside? Maybe you didnt get it back on there right. /forums/images/graemlins/confused.gif
I would remove it & try to install it again, if you need any parts just ask, we have a 1610 basket engine on a pallet.
www.ernies.net

 

[mark777]

Bruce, Thanks I needed to hear that. No I never removed anything but the pump, top and bottom hydraulic lines. But, as I slid the pump back in and had some difficulty meshing the gears...I slightly moved the fan & belt, and the pump slid right in.

I thought the hyd. pump and injection timing were independent from each other...but when I operated the tractor, and it ran so poorly - I worried that I somehow messed up injection timing by moving the engine fan and belt (?)

 

[mark777]

Hey Ernie,

My post was too wordy and confusing. What I meant was I only pulled the hydraulic pump off, replaced the seal and stuck it back in.

Do you think it's coincidence and is it possible that the fuel injection just went bad? If so, I would be very interested in you injector pump.

Thanks Mark

 

[HGM]

Sounds stupid, but what are the posibilities that you sucked a rag in the air cleaner or something? Black smoke means not enough air for the fuel.... Could be a coincidence.. Just a thought..

 

[mark777]

Right now I am entertaining all possibilities...although I am 99% certain that hasn't happened, that 1% may make me remove the intake manifold. And the feedback has been limited about any direct connection between the hyd. pump and injection timing. I'm stumped quite frankly.

Thanks for the ideas.

Mark

 

[HoyeTractor]

What are the chances that you may have bumped the governor linkage when removing the hyd pump? We had a a tractor that had the nut on the end of the hyd pump come off and bend one of the weights on the governor. Did the same thing- fluctuating rpm- no power. Very hard to figure out. I know your pump was in one piece but could you have possibly bumped the governor linkage or something with a wrench while removing the pump?

Couldn't running the tractor with way too much oil have damaged a piston or rings? Does the engine start easily? Excess "blow by"?

Was the tractor running great one day and then started smoking or did it do that when you got it?

You will not be able to accidentally change your injection timing. You would have to remove 4 bolts, governor linkage, fuel lines, injection pump, and then add or remove shims to change it. I think you can safely rule out a timing problem.

Aaron
Parts@HoyeTractor.com
(940)592-0181

 

[mark777]

Hey Aaron, Thanks for responding.

Zero chances of accidentally bumping anything inside during or after removing the pump, as I am the only one that worked on it.

The engine, even now, runs strong with no blow by. Removing the valve cover filler cap and operating at normal RPM's and also looking at my clear vinyl tubing running from the valve cover breather shows absolutely no smoke or any oily residue.

I am (nearly) certain that the engine wasn't damaged as it runs strong, doesn't smoke other than unburnt fuel and has tremendous exhaust pressure like all good running Yanmars.

It does not start easily and never has. It takes three or four attempts with the decompression handle to fire up....warm or cold. It also has always emitted too much unburnt fuel with the eye irritating and smell in an enclosed area. Even though I replaced all 3 injectors, (pulled the tank, bowl and replaced with new filters) which made it better, it only helped minimally.

I have to say that when it blew the seal and bellowed white smoke, I shut it down immediately. I did not restart it until you sent me the seal, I drained everything and removed and replaced the pump. Upon restart, it still ran strong and even, but with the drastic loss in power when I engaged the box blade.

Anything here give you any ideas??

Thanks, Mark

 

[normde2001]

Mark, I believe I would troubleshoot from scratch on the hard starting issue, (Yanmars should not be hard starting). Pull the muffler and fire it up, be sure fuel lines are well-bled and filter good/new. Remove injectors and re-install upside down on banjo fitting and check spray pattern when cranking. pull the head, have a look-see and replace the head gasket.