setting injector pump timing by ear

[auag]

in the past i read a post on the forum about setting the pump timing by ear..but i cant seem to find it...can anyone hear tell me the procedure for timing by ear?..thanks

[82vdub]

With the cold start cable pushed in, your advance the IP until you hear a louder diesel sound, like marbles dancing on a plate, then you back off on the timing a bit. You should hear a difference in engine sound with the cold start cable pulled v's pushed in. After doing that, untighten the hard injector lines to relax them, and then snug them up again so you don't exert a twisting motion on the lines. It's that simple. If you just loosen the IP nuts a tad bit, you can even do it while it's running by a vice grip on the throttle bracket or something. I don't think I ever had the guts to do it while it's running, afraid I'd run the belt off the pully or something.

[auag]

do this cold or after the motor is warm?

[TylerDurden]

Engine warm.

[greg lousy]

I found it difficult with my untrained ear to find the precise "just before marbling" point, did it a few times with decent but mixed results, so now I advanced the timing just into marbling... measuring mileage and paying attention to the feel of the engine, and now I'm retarding the timing a mil. or so at a time for a tank or two, measuring mileage paying attention, etc... really trying to hone in on it. My upper timing cover has a cap that allows access to the bottom bolt, making adjusting the IP about a 10 minute job, so I figure why not experiment.

If I was one of these pros, this would probably be unneccesary... just sharing my more remedial, learning based process

[Fatmobile]

That's exactly how hillbilly tuning works.
Get it in the general area by ear then drive.
Move it a hair and try it again.
Keep moving until it gets worse then move it back.

[vwtyp133]

That's exactly how hillbilly tuning works.
Get it in the general area by ear then drive.
Move it a hair and try it again.
Keep moving until it gets worse then move it back.

Yep... I think I just heard hagar laughing!

[greg lousy]

... and here I thought you guys were just nailing it right off the bat with your super diesel senses

[TylerDurden]

It helps to have matched pop pressure on the injectors, they will start to clatter around the same point. Smilage will be better too, since they will be timed more accurately.

Tweaking is fun, but a good sample size is a couple tanks, and that can take weeks to burn unless you drive a lot.

[air-cooled or diesel]

if your engine is running right; compression -good,& timing right on- youll hear a distinctive diesel clatter at a point of advance. then follow 82vdub's advice. im of the opinion to loosen both ends of inj lines and re-snug. if your engines not running quite as good i wouldnt do; it can be harder to get it to clatter/by advancing pump/ and you may end up over-advancing an engine thats tired, or off and causing problems; in this case use static timing.

[Quantum-man]

Turbo'd engines tend to clatter less. Running up a local hill at different timing settings is a good way to optimize.

[air-cooled or diesel]

i prefer setting static, dial gauge and all, 0.94mm dial@tdc works real good; i also havent touched my factory-set smoke screw and without cetane2 d( ), i cannt judge smoke as accurately. but at hi-rpm full throttle i start getting smokey. at lo-rpm usually little/no smoke.

[air-cooled or diesel]

0.94mm @inj pump may vary for your set-up; youll have to do some research for your motor-set up.

[VW cat]

I tried adjusting the timing on a running 1.6 once. Quite an educational experience, the difference in sound that the engine makes. Too much advance and it does indeed sound like you are working in a ball bearing factory.

[Fatmobile]

It's a bit scary turning it while it's running that the first time but it does give you a general idea of where it likes to run and what different timing settings sound like.