Catastrophic engine failure

[Ronmar]

Do you have a dial indicator?  One with a magnetic base and arm works best(about $20 at harbor freight tools)  If so, first pull the injector and using a long rod and the dial indicator determine TDC and mark the flywheel.  I actually put my marks offfset, and aligned with the banjo fitting on the injector pump as it is nearest the flywheel.  Once you have a TDC measurement, you can measure the circumference of the wheel and divide by 360 to put any other degree marks you desire.  Once the wheel is marked for TDC, setup the dial indicator to measure the intake valve.  If I recall correctly, the intake valve should start to open at approx 5 degrees BTDC, and be approximatly .020" open at TDC.  This of course assumes proper valve lash adjustment...

One quick check is to make sure the fuel rack is opening ALL the way at startup.  You could have something hanging up in the governor mechanism not allowing full rack opening.  You have smoke, so you have some fuel.  Do you have a good solid injector "creak" when cranking, or is it a groan or smaller set of "tinks"?  If the timing is correct, it sounds to me like you don't have all the air bled out between IP and injector.  A little air in the system will absorb the injector pump compression and only partially fire the injector, or cause a series of small firings.  Crack the nut at the top of the hardline near the injector and wrap a rag around it, open the fuel rack all the way, and rock the flywheel back and forth(1/3 flywheel turn?) across the injector firing point to purge the hardline.

[luv2weld]

What was the temperature when you were trying to start it??
If it is cold, then the only thing thing you need to do is warm it up with a heat gun.
Do you have glow plug installed and working??
My own experience is that it will start just fine until the temperature gets to about 20 degrees F.
After that it needs a little warming to get it going.

Ralph

[mbryner]

1. Good "tink" from injector and I purged the fuel line.

2. I didn't do the detailed spill timing.

3. Great compression without fuel.  With fuel I can crank it over the compression stroke and it smokes but won't fire.

4. Temp outside around 40 degrees, but I had a kerosine heater running in the powerhouse so it was about 60 (?) deg inside.

5. Valve clearances seem OK and I set valve lash at 0.017 for intake valve and 0.032 for exhaust.


I think the engine is just a little retarded (pun intended).   I'll check the governor mech also.   I didn't change any adjustment bolts so my guess is that I'm off a tooth on camshaft.   Can't go back out there until tomorrow.  Working until late tonight....

[playdiesel]

I would check cam timing first and it is so very easy that I cannot figgure out why there is so much hulabalu about it. Your valves should be in overlap every other stroke when crossing TDC pure and simple. What a person needs to realize is assuming the engine was EVER right (and yours appearantly was, it was running OK was it not?) that you cannot be off just a little bit, you have to either right or very close to it, or off a lot when you reassemble one. Thus the quick check for proper cam timing requires no gauges or micrometers nor even a manual. You do however need to know where TDC is. Once you have found and marked TDC turn the engine over and watch the valves operate. When you come to the spot where the exhaust valve is just closing and the intake is just opening you are in "overlap", you should have clearance at neither rocker at this point. Now look at your mark. It should be at or very near TDC, by near I mean within a half inch measured on the rim of the flywheel.  If your cam timing is off it must be off at least one tooth correct? Cant be off a half tooth or you have REAL problems, LOL. So if it is off one tooth you are not going to be anyhwere near your TDC mark, I am talking like a couple inches off at the rim of the flywheel. Your cam timig can be off a tooth and you will still have good compression, Some engines will even run a tooth off but not very well. If you find yout timing to be off turn the engine to valve overlap, remove the idler gear(cam should remian still but watch), then turn the flywheel to TDC and reinstall the gear. You may have to turn the flywheel just a bit either way to faciliate the mesh. Like I said once you understand and know where your overlap and TDC points are located you only have to remember that you have to be right, or off a lot UNLESS it was never right to begin with.

[XYZER]

There are many reasons for a new or rebuilt engine not to start the first time.....AIR in the system will make you check everyting twice....If you don't have a puddle of diesel on the floor and you can't taste it you need to bleed the $hit out of it....one little bubble will drive you nuts! One tooth will give you about 8 degrees and the piston will hit the valves if it's to far off. Be carefull jumpin the idler gear around.....I'm bettin air!

[Crofter]

Make certain that the camshaft (valves) is properly timed with the crankshaft before bothering to do spill timing. (Setting spill timing correct with valves off the mark will really screw things up). The advice is good about having the middle of the valve overlap period occur at piston top dead center. This is the end of exhaust and start of intake stroke and is one complete crank shaft rotation from top of power stroke. Because of the difference in valve clearance setting it may not be PERFECTLY centered but will definitely show if you are one or more tooth out. Ronmars figures are correct too and I would only add that you must be sure that you are turning the crank in the proper rotation while noting the point of opening or you will be out to lunch. That has happened!

Air in the high pressure delivery side will effectively delay the start of injection even though you are hearing the injector fire somewhat, and getting some smoke, it will not take off. A full delivery is only a fraction of a drop so it does not take much air to create a big effect.

Pump spill is changed by thickness of the pump mounting gaskets or shims and unless you have done something wild there, that should not have changed.

[bschwartz]

Isn't pump spill changed by the nut/adjuster under the pump on the shaft?

[flywheel]

Isn't pump spill changed by the nut/adjuster under the pump on the shaft?

On the listeroid it sure is!

[playdiesel]

Isn't pump spill changed by the nut/adjuster under the pump on the shaft?

Yes

[Crofter]

Isn't pump spill changed by the nut/adjuster under the pump on the shaft?

On the listeroid it sure is!

I have a big flat spot on my forehead now!    Wrong engine )

In any case you should not suddenly have to re do spill timing.

[mbryner]

In any case you should not suddenly have to re do spill timing.

Didn't think so, that's why it wasn't on high on the priority list.   

Thanks guys.  I'll recheck the fuel lines before moving the camshaft timing.

[Ronmar]

I meant to say Creak instead of tink.  As you bleed the system, first you will get a tink, then a pair, then a tripple, then 4 then 5 or so.  As you crank the flywheek faster and faster, these multiple tinks blend into one longer creak.  If you are only getting a single tink, then you probably have some air, and are delivering enough fuel to smoke, but not enough to increase RPM...

[playdiesel]

I meant to say Creak instead of tink.  As you bleed the system, first you will get a tink, then a pair, then a tripple, then 4 then 5 or so.  As you crank the flywheek faster and faster, these multiple tinks blend into one longer creak.  If you are only getting a single tink, then you probably have some air, and are delivering enough fuel to smoke, but not enough to increase RPM...

So let me get this straight,
You bleed until you, get a creak,
then a tink
Then two tinks
then a tripple tink
Then the creak


Just messen with ya, actualy that discribes the sounds pretty well, LOL

[mbryner]

triple tink-le sounds like a prostate problem.... 

[slowspeed]