TD42 fuel filter change, runs worse

[Ricor]

I am in the process of figuring out why my just purchased 1996 Patrol TD42 is slow, seeming to be the turbo not working.

First step was to get a boost gauge (will be here tomorrow) the to change the fuel filter.

I changed it today.

Before change:

Ran great, but low power and top speed (65mph).

Old filter had grey crud in the bottom, and the filter was only 1/2 full of diesel when I removed it (I did not drain it before removing)

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I cleaned the water sensor, lubed the o-rings and reinstalled.

I filled new filter with diesel, however it was older fuel from a good running diesel generator with red offroad diesel fuel. The generator runs fine, has a mix of old fuel topped off with new fuel every so often. It should be OK but thought I would mention it.

She fired right up, idled fine.

Took her down the road slowly, ran fine.

Went out to the main road and put her in neutral and lightly revved her and she blew a little white smoke, and sputtered some, something she had never done.

Drove 7 miles, slower than before acceleration and about 52mph top speed, without pushing her. At 52, smooth, no noticeable smoke.

So lower power, slight sputtering, did not change with 7 miles of driving. I'm thinking run her more, but don't want to risk something I am not aware of. Maybe on to the gauze filter?

I appreciate any thoughts.

[Ricor]

SOLVED - probably

I moved on to change the gauze filter in the injection pump. It is so small it was hard to tell how dirty it was. Cleaned it with carb cleaner, it looked perfect and obviously was dirty. Reinstalled, and WOW. She pulled like a beast, and not pushing her very hard 0-60mph went from 39 seconds to 15 seconds.

Will test the boost pressure this weekend but it is looking good.