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Engine Specific Info and Questions => mTDI Mechanical TDI Conversions => Topic started by: Meilleur on August 12, 2018, 07:36:22 pm

Title: Ahu mtdi knock
Post by: Meilleur on August 12, 2018, 07:36:22 pm
hellos

i have an ahu with a cummins pump 4bt 11mm head tdi.

he is timing at 1mm ip

he has a clacking noise when you give fuel!

what could be the cause?

Sorry I’m français!!



https://youtu.be/3hJ7esUsLZk (https://youtu.be/3hJ7esUsLZk)



Title: Re: Ahu mtdi knock
Post by: libbydiesel on August 12, 2018, 08:39:42 pm
Cummins 4BTA pumps had 12mm plunger/head assemblies.  Because of the larger plunger the fuel is delivered in a shorter injection event so the clatter is more pronounced.  When I listened to your engine, though, the steady louder lower frequency knock sounds like a bad injector. 
Title: Re: Ahu mtdi knock
Post by: Meilleur on August 12, 2018, 08:51:54 pm
https://youtu.be/PhnGbwfbBz4


thank you for your answer here is another video.


Envoyé de mon iPhone en utilisant Tapatalk
Title: Re: Ahu mtdi knock
Post by: libbydiesel on August 13, 2018, 11:46:57 am
Wind noise makes it a bit hard to hear, but it sounds fine/normal to me in that video. 
Title: Re: Ahu mtdi knock
Post by: ORCoaster on August 13, 2018, 10:55:23 pm
Wind was a bit hard to filter out.  I wasn't sure that there was a knocking noise that was abnormal.  Maybe a listen with at solid rod from ear to injector will help find any that are louder than the others.  I use a breaker bar and that seems to work well enough. 

Timing of 1.0 mm?  Could a change one way or the other make a slight difference for you?

Title: Ahu mtdi knock
Post by: byronEsset on May 13, 2019, 04:11:58 pm
Easiest route is to use the sd16v compressor on the AHU, an yes you will have to clearance the core. You could probably use the cabrio compressor but I am positive that would a larger undertaking.
There are adapters available to use the cabrio hoses on the AHUs compressor.