Oil & Fuel Fuel Pump Timing Help??

jbitting · Apr 1, 2006

Mark,

Wonder if an intake valve not opening properly would cause this... of course, if that's the case, it would probably indicate more serious problems lower in the engine. /forums/images/graemlins/frown.gif

just a thought...

Once you figure this one out, be sure to let us know...
We're all quite curious about this one.

Jake

YanmarFever · Apr 2, 2006

Mark, I have an extra 1610 hyd pump on a parts engine.
We could send it to you so you could try it out and see if thats your problem. your only cost is shipping between us if it doesnt work.
Ernies imports

DavesTractor · Apr 2, 2006

Mark,

Does the hydraulic pump gear act as an idler gear, so to speak, for other gears that could run the injection pump? When you had a hard time getting the gear back in and had to move the fan a little, you could have something off by a tooth. We put a Branson together once with the gears off by a tooth or so and it caused me no end of grief until I pulled the front off the engine and put everything in exactly right. Then the smoke went away and the power back up to normal.

Maybe Aaron or Ernie could comment. Is my scenario possible? Essentially the crank got turned a little but the injection pump didn't because the gear was out? I know it works that way on some engines, not sure on the Yanmar.

mark777 · Apr 2, 2006

HGM ,
Fuel is fresh and I have filled three other tractors with same..everything's normal.

Jake,
The intake is air and seal-only on a diesel as the injectors spray into cylinders...if it were gas that would be one of my first guesses though.

Ernie,
Thanks for the gracious offer, but the hydraulic pump is working perfectly...I was hoping for a connection about disturbing the fuel injection pump when I removed and replaced the hyd. pump, but I don't see how they are related (timing wise anyway).

Dave,
The majority of Yanmar dealers and suppliers, including Aaron @ Hoye, state the timing of the fuel injection cannot accidentally be changed...you have to physically remove or replace shims and/or take the injection pump apart. But your scenario is what my primary concern was at the beginning of my post.

Thanks everyone.

My intentions were to remove the timing cover...because if I don't I'll always wonder. If everything is aligned on the marks, I will remove the head and determine the internal damage to head and block (rings, pistons, walls etc.) I ran out of time this weekend completing other projects, but it's off the back burner and I'll start on it this week.

Mark

bruce1966us · Apr 2, 2006

If memory serves me correctly, the valve camshaft and injector camshaft run directly off the crankshaft. The hydraulic gear can run at any position. Does the engine run smoothly at any RPM?

bruce1966us · Apr 2, 2006

Mark, you won't find the timing marks aligned. When the engine is initialed "timed' the marks align. After that , the engine must turn xxx amount of revolutions before the marks align again. Try it and you will see!!

mark777 · Apr 3, 2006

LOL, yeah..I meant rotate the crankshaft until the marks align.

greatrandini · Apr 3, 2006

I still say you have air in your fuel lines! Simple fix!
Later dude!

mark777 · Apr 3, 2006

Great,

3 Weeks ago, I replaced fuel bowl, O ring and retainer nut, jar and valve assembly...all new urethane fuel lines from the tank, from the fuel filter, to the thermalstart and bleed completely. I then switched all the metal lines, fuel bowl assembly, urethane lines and injectors from one 3T75U engine to another, bleed and ran the other tractor...it runs perfect and not one hiccup. Anything fuel or air related has been replaced with new...even hose clamps OR swapped with known components that check out O.K with another good running tractor.

I was then, where you are now...hoping for and eliminating all the simple fixes. And what you stated in your post, it would be the first thing I would recommend to another member to look for. I do appreciate your, and everyone's suggestions, no matter how simple or far fetched, as I did NOT want to tear an engine apart that show no signs of blow-by but I am out of ideas.

Mark

greatrandini · Apr 3, 2006

Well maybe u r off the mark? When u tear it down keep us posted. I assume u bled the fuel lines all the way to the injector pump? U can crack the nut on the flare fitting at the injector line.(bleed from there) I am sorry if u know all this already! I just hope to save u some work.