how to recognize a worn/dirty injector?

Getting the pumbing right for your Diesel fuel feed..

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arnaud
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how to recognize a worn/dirty injector?

Post by arnaud »

Hi, Although i've lot's ao experience with (the revision of) petrol engines (BSA, enfield, ural, dnepr). the diesel engine is quite new to me. Also i'm quite reluctant to take it apart, as by my first moped, i'm afraid to mess things up.
But, i don't know the details of a diesel engine.(i know the bsaics, but lack the experience)
Although i blame the cold for bad starting, some say an worn(it is chinese)or badly produced or carbonized injector may be a part of the problem.
How do i recognize it? do i have to take the nozzle apart to clean it(with cleanig-petrol or alcohol i am told?)
Pic's are more then welcome!
Is it advisable to take the head of after XX km's for de-coking the engine?

I tried to find a diesel-engine forum or other websites to find this specific info but alas..
I want to know this stuff, so i am prepared when the engine seizes to work properly.
Other mentioned bad timing, but this cannot alter very much since it is sprocket-driven?
Greetz
arnaud
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andrewaust
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Post by andrewaust »

You should get around 250, 500 thousand kilometers out of an injector, that is if your keeping the fuel clean and running the engine within its perimeters.

You shouldn't have to de-coke a diesel, if you do somethings not right.

A bad injector will not atomize the fuel properly, meaning hard starting and white smoke and sometimes a really bad diesel knock which is destructive for the engine.

Direct injection injectors do get a build up of deposits over time that decreases their efficiency. the most destructive thing I've seen, when heads are taken off direct injected engines with the injectors still in and sat flat down on the ground = there probably goes the injectors, they nearly alway protrude past the head face.

Indirect injection injectors tend to wear the face starting from the pintle needle and where the air and fuel swirls in the pre-combustion chamber.

Google spill timing for diesels, hopefully you'll find something that will run you through the steps to check timing.

To diagnose a diesel from a distance is really hard if not impossible. For a simple engine they can give you problems when something is out of kilter.





;)
Nanko
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Re: how to recognize a worn/dirty injector?

Post by Nanko »

arnaud wrote:do i have to take the nozzle apart to clean it(with cleanig-petrol or alcohol i am told?)
Pic's are more then welcome!
Its not a good idea to take it apart , clean it and trust the result is OK
Injectors are very sensitive for dirt

Better take the injector to a BOSCH service point , for few E. they can test it and for abt 40 more , replace the nozzle .

Or drive to my place ,where you can use my injector tester
peugeot TUD5 - MOTO GUZZI 16.500 km so far
arnaud
I luv the smell of Diesel...
Posts: 387
Joined: Tue Apr 29, 2008 11:11 am

Post by arnaud »

Rottum, thats means swiming. maybe catch a seal on the way back for dinner..
Nanko
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Post by Nanko »

I said drive , not dive......
Dont touch Lenie's seals , she'll kill you when she finds out :-)
peugeot TUD5 - MOTO GUZZI 16.500 km so far
Sphere
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Post by Sphere »

Rottum: http://nl.wikipedia.org/wiki/Rottum_%28Eemsmond%29 (sorry phpBB tags suck)
Rottumeroog: http://nl.wikipedia.org/wiki/Rottumeroog (infidels call this Rottum as well)

Then there's also Rottum in Friesland (never knew that), but lets not confuse the other readers 8)

Panorama pic of Rottumeroog: http://upload.wikimedia.org/wikipedia/c ... norama.png
'92 Enfield + Hatz 1B40: street legal, weld up stainless exhaust, check engine rpm and change final drive sprocket.
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taildraggin
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Post by taildraggin »

I took apart the used yanmar I bought for the bike and it is pretty spotless inside after about 1000 hours of use.

How much veg oil did you burn last summer? It has greater solvent properties and clean it out. Unfortunately, if the insides were dirty, it may have dumped some bits from your tank or lines into the injector.

It does not sound to me like a "3 kicks, cold" problem, though. If it runs well after starting, I wouldn't mess with it at all.
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