Injector Pump Timing

[Anonymous-0]

I have a general question about injector pump timing. What is the rule of thumb when setting the timing. Do you set the timing where the tractor runs smooth with little/no smoke at idle? How will advancing/retarding to much adveresly affect performance? The tractor I am working on now is a IH 47 MD but I am curious as to how pump timing effects diesel engine performance in general. I do not have access to a dyno at this time. Thanks

 

[Dick L]

If every thing is tight and running as it was built I just time to the line under the timing cover on the pump. The pump timing on a diesel can't be off much or you get smoke or loss of power. Or both.

 

[Bob]

I would venture to say it's much like a gasoline engine... Advance is GOOD for power AND economy, but, after a certain point, you'll get "pre-ignition", and break things!

 

[Coloken]

Here at high altitude, 5000 ft, we all ways set spark engines several degrees more advance that specs. Would the same thing be usefull on diesel?

 

[Goose]

I agree with Dick. Go by the book and set it accordingly.

I have a D19 Allis diesel that has almost zero tolerance from factory spec. If it isn't on the money, it just doesn't run right, as opposed to gasoline engines where you can play around in maybe a 10 degree window.

 

[buickanddeere]

The best method is to find the timing "sweet spot" when loaded on a dyno.
Sometimes the factory timing marks are off a wee bit.
The idea with either diesel or gasoline timing. Is to run as little advance as possible without loosing power or economy.
High advance numbers sound good in a conversation. However they cause the engine operate under higher stress no HP or economy gain(s).

 

[JDemaris]

Most diesel injection pumps have an automatic timing advance that increases with load and RPMs. This is usually the first thing to wear in the pump and get sluggish. So, when you start fooling around and experimenting with timing, you cannot have it both ways. You may get it running good at low speeds, or at high speeds, but if the advance is worn - you never going to get right with both.

If you want to know for sure, you need ot check the advance, just as you would with a gas engine and timing light. On a diesel, you can also use a timing-light hooked to a "pulse-adpater" on #1 injector line. Also, some pumps - especially Roosamaster/Stanadyne can be checked by bolting on a $5 plastic degree window.