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Nessmuk
02-01-2017, 12:41
As I don't have the timing light or pointer on the timing cover,
How do set my timing?
What adjustments will get me max output from a DB2 4911?

Robyn
02-01-2017, 16:41
Welcome to TDP :):)

This is a guess for sure but we can get close ;)

Does the top of the timing cover where the injection pump bolts on have a mark scribe'd or stamped across it front to back ???

If so align the mark on the IP with the mark on the cover where the IP and cover meet.

The engine should run fairly well, at least it will be close enough to start and give you room to fiddle with it.

Get the engine warmed up well (TEMP IN NORMAL RANGE OF 180/190)

If the exhaust shows any bluish or white smoke after it's hot then the IP is retarded.

Advance the IP a line width at a time (marks on IP) UNTIL smoke clears and engine runs crisp.

Retarded timing will also make the engine harder to start cold.

DO NOT attempt to adjust the IP with the engine running.

Without a timing mark on the front cover and a timing meter it will be hard to get accurate.

An exhaust temp gauge installed in the cross over/head pipe just below the manifold can be quite useful.

Run the rig under a hard load on a good pull and observe the exhaust temp.

Max reading should not exceed 1000 F

Retarded timing will cause higher temps.

That is about all I can give you to work with.

Seat of the pants for sure.

When the engine is warm and idling it should have a nice crisp cackle to it with a clean tail pipe (If all else is in good order)


Good luck and keep us posted.

Robyn

Dvldog8793
02-02-2017, 10:28
Howdy
Sorry for jumping in on this but....
Good Response Robyn! What direction do you move the pump mark to advance?
Thanks!

DmaxMaverick
02-02-2017, 11:57
The IP rotates opposite the crankshaft and a V-belt driven fan. It rotates the same direction as a serpentine belt driven fan (which also rotates opposite the crank).

Advance = Opposite direction of IP rotation.
Retard = Toward direction of IP rotation.

Robyn
02-02-2017, 19:13
What Maverick said :):):)

Certainly not the high tech method of timing these beasts, but I have done it this way before due to lack of timing meter and or marks on the front of the cover.

If the thing starts and runs good and the EGT is in the groove then your off to the rodeo.


Also as the timing chain wears the pump timing lags a bit and a little tickle more advance helps a bunch.


Great fun

Nessmuk
02-03-2017, 08:04
My motor, pump and injectors are fresh and the timing gears and chain new. I figure now is the time to get this too.