Hi everyone: Have a 6cy turbo 300D runs smooth when cold , but when warmed up intermittently feels as though is "missing", anyone out there lend a hand?
Thanks

dab

The first step is to attempt to track down the culprit cylinder.

Crack each of the injection hard lines until the cylinder gets no fuel. Observe the behavior of the engine. You're looking for one cylinder that doesn't really affect the idle speed or the current idle behavior. The other five cylinders will clearly show lower speed and noticeable shaking. If it's actually running on four cylinders, it might even stall.

If you can find the cylinder, then it's time to switch injectors to see if the problem follows the injector. If it does, then you've found the problem. If it does not, then the delivery valve on that cylinder becomes suspect.

Ok, thanks, will try this out tomorrow. Should I take the injector apart and look for obstruction?

dab

Definitely not. You won't have the tools for this task or the knowledge required. There is some risk in getting it reassembled without any leakage.

It's time to send it to a proper injection shop at that point.

Thanks for the reply, saw the adds on Diesel Giant for replacing the injector nozzles, not such a good idea or what?

thanks

thanks to everyone for the injector tip, but.... was wondering if it is in fact the injector, how come it is ok cold but acts up when warm, any ideas?

dab

How hard is it to start?

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Jim

The nozzles from Kerma seem to be a quality product. The installation of those nozzles and the resulting performance is not always a panacea. Sometimes they will leak and sometimes they need to be balanced.

But, you're getting ahead of yourself here.........

Starts very easily, no problems. Runs smoothly until warms up, then is rough.

dab

Check the fuel filters.

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Gone to the dark side

- Jeff

I service it regularly, all filters changed about 1000 miles ago. Was doing this before filter change also.

Think I am going to try the injector line loosening tip and see if one of the injectors may be the culprit.

Thanks for the reply,

david

my wagon does same@115k. i believe slight imbalace of delivery valves. gov racks more fuel when cold to overcome thick oil,when warm rack tapers off fuel quantity and imbalance becomes noticable when eng shakes at idle in gear. all 5 cyls hot and firing. what say you? aloris

Good point, will know more tomorrow when I loosen the fuel pipes,

david

Have to sign off for now, thanks to eveyone for the help, will post tomorrow what I find,

david

If it only idles rough, possibly even a small fuel leak between the IP and the injector. At idle, there is very little fuel injected, a tiny leak is significant.

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Gone to the dark side

- Jeff

Same problem here. Just wanted to post so I can get instant email notification...

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1983 MB 300SD Turbo Diesel