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Engine Specific Info and Questions => IDI Engine => Topic started by: 33B on December 05, 2022, 10:19:31 am
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Okay so my NA to TD engine died (pison rings no longer exist). So I swapped a JR td. Good engine runs nicely. But I want to get boost like before 1.5 bar max. So I started to screw in the fuel screw but its auto revving.
I screwed it in maybe half a turn and as soon as you touch the gas pedal it starts self revving, also rev hang at 3k. Why is that?
Pump is timed correctly by myself at 1.02mm as bentley's book says.
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My condolences.
Half a turn is pretty far.
Does it still have the limiting collar?
That's what happens when you turn the fuel up too far.
The rpms hangs and or rise.
Or it could be a bad spray from the injectors. A pissing injector will partially burn, then have fuel left over the next time around.
Smoking white?
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Thank you, your so kind.
No white smoke. It was turned to the collar. I guess the previous owner did that. And yesterday i removed it and it self revved. But the rev hang was there before i touched it.
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It's probably the stretched choke spring inside the pump, a small spring that is attached to throttle.
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A "choke" spring?
There is a spring going from the cold start to the "accelerator" inside the pump,..
on pumps with the increased RPM tied to the cold start lever. The extra stuff on the back of some pumps.
Otherwise there is no "choke" or springs connecting the cold start to the levers inside.
So you removed the limiting collar?
That will just allow you to have more rpms hang as it allows even more adjustment in that direction.
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I don't have that RPM increase thing.
Anyway I fixed it. Screwed it out a bit more no more rev hang. Why I couldn't get more boost, well I forgot I reset the wastegate screw when i took out the exhaust manifold....... Tweaked the LDA a bit and now it's running like a dream.
I like this pump a lot. You can tweak almost anything on/off boost related. I did disassemble it last week, vane pump was stuck. Cleaned it out and replaced the gaskets. I love having an original TD engine so far. No smoke before boost, lower EGTs with the same boost(could be that the previous engine IP was not timed right, bought the tool 3 days before it died). Running 600C in 3gear 1.5bar, as before i was hitting almost 800C.
And now having a hydro engine I can do the 1.9td head gasket and also a 1.9td head. That will come at a future date. For now I'm done freezing my *** off in a cold garage.
Thank you fatmobile for another great input!
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A "choke" spring?
There is a spring going from the cold start to the "accelerator" inside the pump,..
on pumps with the increased RPM tied to the cold start lever. The extra stuff on the back of some pumps.
Otherwise there is no "choke" or springs connecting the cold start to the levers inside.
So you removed the limiting collar?
That will just allow you to have more rpms hang as it allows even more adjustment in that direction.
Yes thats What i tought.