Anyone assist here? I modified the injector pump (1997 300tdi) for extra power. I didn't touch the main end screw, just the star wheel lowered by ¾ turn and the collar shaved down by 2mm and top screw (pre boost) in by 1 full turn. Although the power is really noticable, I find that on putting my foot down I get a large puff of black smoke. Not really bothered about that but I am about the MOT emissions test. Any ideas?
Black smoke on putting my foot down
- Thread starter lrmonks
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Put it back to how it should be.....if you can!.
I am sue that would be the safest option, but I'll probably leave it and see. Thanks for replying.
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Even if you just undo the bits you can, i.e winding whatever you did back to where it/they was/were, that'll help probably.
Even if it doesn't you'll be able to redo them again.
Thanks but as I said I'll have to see how it goes and if it fails I will return the settings. To do that on the off chance is a pain. I was just wondering if anyone else modified their pumps without MOT issues.
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OK.
I have never done anything to mine but I have researched it, it seemed like a quick and easy job. Maybe it is trickier and more time consuming and/or awkward than I thought.
Best of luck with the MOT. If the testing equipment doesn't pick it up you ought to be OK.
Mot emissions is done at tick over so shouldn’t be a problem
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Not quite, there is a bit more to it.
MOT inspection manual: cars and passenger vehicles - 8. Nuisance - Guidance - GOV.UK
Noise, exhaust emissions, engine malfunction indicator lamp (MIL) (sometimes called an engine management light or 'EML'), and fluid leak rules and inspection for car and passenger vehicle MOT tests.
I had a memo from my MOT centre last year and the said that they will run the engine at high revs for a prolonged period and could take responsibility for any issues. This did worry me at the time. Tickover was the norm once as you say. I'm sure they're trying to wreck engines.
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If you read the link you will see what they should be doing. "Prolonged period" is rubbish, but they do need to rev it up to the rev limiter for a short while.
This is why they check with you that your cam belt has been changed according to normal protocols.
This is what I found after a search -
I first qualified as an MOT tester in 1985, and the diesel smoke test was introduced some time after that. I always felt that the test was flawed, and that it was totally unnecessary to rev the engine right up to its limit. The vehicle would never be driven in such a way, and so why the need to test it that way? It was well documented at the time that certain procedures must be followed, and that we must be aware that engine damage could occur. Everyone knows, or at least should do, that you should not rev any engine up to its limit without any load on it. Many modern cars are set so that it can't be done, and just as well too.
trouble is a 1997 Defender won't have a limiter as above.
I first qualified as an MOT tester in 1985, and the diesel smoke test was introduced some time after that. I always felt that the test was flawed, and that it was totally unnecessary to rev the engine right up to its limit. The vehicle would never be driven in such a way, and so why the need to test it that way? It was well documented at the time that certain procedures must be followed, and that we must be aware that engine damage could occur. Everyone knows, or at least should do, that you should not rev any engine up to its limit without any load on it. Many modern cars are set so that it can't be done, and just as well too.
trouble is a 1997 Defender won't have a limiter as above.
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Is this you posting about yourself? Or just some quote from a thread/article you have found?
As I said, and posted a link to, there are protocols that the testers should adhere to. Which will not endanger your engine provided your cam belt is OK.
If you are at all worried go to another tester.
Thanks. I did say that I found the article after a search.
I will however contact the station (which are very good) and address that part about their memo on reving up the engine without load, but my main question was regarding injector pump mods to increase power and if that could affect the emissions test and wondered if anyone else found that was an issue at all. The engine had a new cambelt but I don't do much mileage in it tbh so I am sure that's fine. I did read the link btw and thank you for that.
I did find the original memo as follows - 'Please note that as part of the MOT test, Diesel engines are run at high revolutions for sustained periods of time, it is important to be aware of the condition of your diesel engine, especially with regard to things like camshaft drive belts prior to having an MOT carried out.'
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all diesel engines have some kind of governor, even an old defender. this limits the engine speed. The mot redlines the engine to check the function indirectly as part of the test
Yes I agree they have some kind of governor but I don't think they want to check to see if the governor is working correctly, but I may be wrong. Doing that would only take a few seconds but from the memo they said 'sustained periods of time' so that can't be just a governor check. When I mentioned this I was just responding to a point that someone said it's done at tickover and this wasn't really my main question.
Anaconda
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They have a throttle stop which is a threaded bolt you wind in and out.
If you have been messing around with your injection pump you will have seen this.
Wind it in so it will only do 2000rpm if you are worried. If you are really worried then you shouldn't have messed around with your pump.
You would have been better of getting the pump and injectors refurbed and the timing set.
We did this on the 200tdi and it goes really well and made a big difference.
There are many adjustments you can do on the pump.
The top screw and star wheel can both effect off boost fuel delivery, hence why it feels better to drive, but as it is off boost the fuel is not being fully burnt hence your smoke.
You will find most adjustments everlap others so it can take quite some fiddling to get nice power and minimal smoke.
The top screw and star wheel can both effect off boost fuel delivery, hence why it feels better to drive, but as it is off boost the fuel is not being fully burnt hence your smoke.
You will find most adjustments everlap others so it can take quite some fiddling to get nice power and minimal smoke.
Yeah, that is a point but after modding it I haven't had the time to fiddle around with it yet due to life lol. Just wanted to know if anyone else had an MOT issue after the boost. Thanks for you reply.
D1Nut
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Revving up the 300 tdi under no load wont make any black smoke.
I did the same as you but at most half the twists and turns you have and that little bit extra grunt on pull away is so so nice.
I did the same as you but at most half the twists and turns you have and that little bit extra grunt on pull away is so so nice.
