Smoking after IP timing.......
 

So, I retimed my injection pump finally. Was at 20*BTDC.. Retimed to 27-28* BTDC... Has much more clack at start up, and though I've only driven it in the driveway etc, it seems to have a little more power.... BUT, it smokes profusely at idle... Even when warmed up. Is this to be expected? It really doesn't bother me, (I LOVE SMOKE!!! ) as long as it's par for the course....

Will this cause my oil to soot load faster? I have a toilet paper bypass in service.......

Thanks!

Here's a "smokin" picture for yall........

Just a thought - the pump timing spec for a 617.95x is 24 deg BTDC +/- 1 deg. what did you not set it to that?

I think black smoke is okay at WOT, but white idle is not so good, IIRC. Might not kill anything overnight, but I think it will leave build up. Anybody want to correct or substantiate?

Black smoke it not ok at all at wot. That is unburnt fuel. Same with white smoke (however it looks like his is very small). Set the timing to 26 max. (This is what FI is using IIRC). and see if that fixes the white smoke. That extra clack might be preignition or a million other bad things.

Oh, the Finn guys say to go 28*.... So I set it at 27ish because that was easy to hit and a compromise between 28 and the stock 26.......

Stock is 24º, not 26º BTDC. FWIW

The Finns are pushing alot more fuel as well. Unless your pump is modified keep it 25, 26 max.

I talked to the VW/MB tech at the local Diesel shop. He said the following:

1: Is it hard to start? No, starts just as well if not better than before.
2: How many miles on Injectors? Unknown, but probably original @ 231K miles..... Ding, Ding.... Problem here!!

Given those answers, he thinks that I've done the right thing. He said that if I went much too far over the 28*, that it would be very difficult to start, especially after I told him that without glowplugs or ether, there is absolutely no way to get the engine started when not at operating temp......... Even in warm weather....

He says that's normal behavior for a cold engine, but says that hot the smoke should clear up. Said also not to be worried about too far advanced timing doing damage as, once again, it would be hard to start long before the damage point. (And yesterday I started it effortlessly with the battery standing at 12.2 volts!! :eek: Needless to say I let her charge up!) Also said that with the amount of idling I've been doing lately, that until I run 'er good, smoke is an unlreliable signal, at best...... Plus the fact that he feels pretty certain the injectors are shot. Said that they'd pop & spray test for $3.50 ea...... Rebuild for $60ea, including nozzles... Seems a bit high since I can get new injectors from Rusty C for ~$48 ea......

That's what the Bosch tech had to say............??? Anybody have thoughts otherwise? :confused:

Your timing is off. Here are the values taken from the Hayne's manual:

Turbo Charged Engines:
23 to 25 degreees BTDC

Non Turbo Charged Engines:
615.913: 26 Degrees BTDC
615.912: 24 Degrees BTDC
616: 24 Degrees BTDC

Some people go slightly higher at high altitudes but that's about the only time I know of.

Scott

I dont fully understand the ramifications of advancing the timing like that, but, you are having a problem after making a change that is outside of spec. Id go back to spec and start there.

Whats the measurement method?

Diesel purge, and then pop and spray test. Rebuilds will only help if the injectors you have in there are somehow faulty.

I have the same white smoke at about the same quantity, so I am quite interested in the results. :D

dd

I guess I really need to get out and drive it some first to rule out the chance that it's just all sooted up from sitting..... Like I mentioned earlier, the diesel place said that they hear it done all the time and the only time you get constant smoke from a 2-3* advance is worn out, dribbling injectors that are "leaking down" between injections...... I.E. Worn out nozzles....... 231K miles is quite a bit.........

I think the mercedes suggestion is to check the injectors every 100k or so. On the premise they may never have been done it will not hurt anything to do so anyways. An indicator of their general condition might have been your fuel milage if known.

Dumb question, how did you measure timing? Baylor or drip or?

Some diesel shops will test your injectors for free. I just took the injectors from my Ford F250 diesel truck to my local shop, and they tested all 8 injectors for free.