DD Question

[TomC]

Luvrbus- I think you read my post wrong-I said that DDEC does retard the timing when cold-more so then mechanical timing-to reduce white smoke at startup.  So if you're getting white smoke at cold startup with a DDEC engine, it is a good bet you're in need of either new injector tips or complete injector overhaul.  Good Luck, TomC

[paul102a3]

Anyone have an idea of the expense to replace/overhaul the injectors? Is this something I can do myself? I do have two stage jakes if that matters.

I have replaced injectors on several Cat 3208s as well as small genset diesels so I have a working knowledge of the process on mechanical engines.

Thanks

[luvrbus]

Paul, you are looking at around 2 grand for parts and another 1000 to 1500 for labor maybe more.
To check to see if they are leaking have a oil sample done if signs of fuel in the oil then change the injectors but I doubt if you find any dealer now days that will just change the tips it is cheaper to replace the whole injector with the price of labor at the dealers.
If you have all the special tools required for a DD and a manual you may can do it yourself but it is not a easy task with Jake Brakes. 



good luck

[paul102a3]

Wow, I had no idea they were that expensive.

I think I'll do the oil sample routine. I did one in April of this year so it would be a good benchmark to help set me in the right direction.

Thanks for all you input.

Paul

[Hard Headed Ken]

I find it unlikely, but don't forget white smoke at start up can also be coolant in the combustion camber (cracked head). Another thing I've experienced is "cold ring stick" where carbon build up in the ring land causes the ring or rings to stick and not allow enough compression for ignition for a few seconds at cold start up. My experience was that only a few degrees difference in ambient temperature would cause this to happen (something like 50 degrees would be no problem and 40 or below would cause a misfire for a few seconds) resulting in white smoke (unburnt fuel). I know carbon was the problem because about 13000 miles after I built the engine it broke a rod and during the re-rebuild process I discovered the ring lands were full of carbon, which I found unusual in such a short period of time. I built the engine again and it was doing the same thing in about the same mileage. The only thing I thought that might have caused this was the big injectors I was running. I never found any chemical that fixed the problem (and I tried many). Carbon is an organic compound. The only thing that I know of that will clean it in a combustion chamber is water. Just take a look in any engine that has the head removed because it had coolant leaking into the combustion chamber (blown head gasket). The cylinder with the leak will be spotless. This was a 6V92

Ken