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Engine Specific Info and Questions => IDI Engine => Topic started by: James8485 on June 03, 2009, 06:47:16 pm

Title: Merc nozzles wrecking a AAZ
Post by: James8485 on June 03, 2009, 06:47:16 pm
i have 1.6 injectors with merc nozzles

i have a aaz and i am about to put them in....

why are there bad reviews from some ppl on here???

i know about the pre swirl or something like that but whats that about???

like you cant wreck anything on the motor can you???      i gots 3000 into the motor alone so if they will cause damage i might want to re consider!

i have already bought them so,,,,,,,,
Title: Re: Merc nozzles wrecking a AAZ
Post by: jtanguay on June 04, 2009, 04:53:36 am
the merc nozzles were designed for a different type of pre-combustion chamber.  i forget the details, but stock nozzles should be able to flow all the fuel you need.
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 04, 2009, 08:25:13 am
If Dave from passenger can grab 180+hp with old worn stock nozzles then I think some new stock nozzles will be even better.
so if I can get 180+hp from stockers why even bother with bigger smokier injectors? I think Dave even lost power with his merc tips right?
Title: Re: Merc nozzles wrecking a AAZ
Post by: ikas on June 04, 2009, 10:09:01 am
i wreck a aaz with merc nozzels!

i dont like merc nozzles
Title: Re: Merc nozzles wrecking a AAZ
Post by: carrizog60 on June 04, 2009, 11:34:16 am
i wreck a aaz with merc nozzels!

i dont like merc nozzles

sorry but i dont believe that was the nozzles...
i had them with pump delivering all the fuel,run veggy for a while and the engine didnt suffer at all.
it must have been something else and somebody put the blaim on the nozzles...

why do you say that you have wrecked it?what happened?
Title: Re: Merc nozzles wrecking a AAZ
Post by: myke_w on June 04, 2009, 12:32:36 pm
The pintle design is definitely different, which makes a different spray pattern, the prechamber is very different, it's much longer in an MBZ.

If the fuel was all being forced into the wrong place because of an incorrect pattern, I would think that could be a problem, especially if it overheated the prechamber.

I'd personally like to see a "side by side" comparison of both spraying through a cross sectioned vw head prechamber.

(http://thedubdoctor.com/vw-documentation/prechamber-cutaway/pre1.jpg)

(http://thedubdoctor.com/vw-documentation/prechamber-cutaway/pre2.jpg)

(http://thedubdoctor.com/vw-documentation/prechamber-cutaway/pre3.jpg)

Maybe I'll do that when I get some free time.  ;D
Title: Re: Merc nozzles wrecking a AAZ
Post by: Vincent Waldon on June 04, 2009, 01:40:50 pm
Fantastic pictures Myke.

There's always been an internet rumour of precups dropping out thanks to Merc injectors, and when you see the cut-away like that you can envision the wrong spray pattern dropping fuel in the wrong spot and overheating the precups... wish I was closer and could help you take pictures 'cause I think it's a fantastic idea for an experiment.

BTW, that head has a pretty big crack in it...dunno if it's reusable...  ;)
Title: Re: Merc nozzles wrecking a AAZ
Post by: andy2 on June 04, 2009, 03:14:12 pm
AAZ nozzles can flow more fuel than a 12mm head can supply them with.They are capeable of flowing more fuel than the engine can handle ! So don't use the merc nozzles if you don't have to.
Title: Re: Merc nozzles wrecking a AAZ
Post by: RabbitJockey on June 04, 2009, 05:10:15 pm
if you use a 1.9 head on a 1.6 block should you use 1.9 injectors?
Title: Re: Merc nozzles wrecking a AAZ
Post by: theman53 on June 04, 2009, 07:54:58 pm
Great reference Myke...is that my old head?
I think with all the posts on this I would stay away from the Merc nozzles and just run the stock ones.
Title: Re: Merc nozzles wrecking a AAZ
Post by: jtanguay on June 04, 2009, 09:48:38 pm
i think the main reason people run merc nozzles is to try and achieve the same power, but it's two different designs.  just look at the gm 6.5L diesels.  apparently the 1.9 aaz nozzle will flow as much fuel as those 6.5L nozzles???  :o

time for mythbusters!!!  ;D
Title: Re: Merc nozzles wrecking a AAZ
Post by: myke_w on June 05, 2009, 08:56:55 am
Fantastic pictures Myke.


I have to admit these aren't my pics, I could only hope to have a head that was cross sectioned, (anybody have a band saw?). I stole them from a site whose identity I can't remember for the life of me, but had to save them because of their illustration value.

Title: Re: Merc nozzles wrecking a AAZ
Post by: monomer on June 05, 2009, 04:06:03 pm
I have a junk OM602.92 Mercedes head here, if anyone wants to cut it up.
Title: Re: Merc nozzles wrecking a AAZ
Post by: andy2 on June 06, 2009, 02:37:29 pm
if you use a 1.9 head on a 1.6 block should you use 1.9 injectors?

You should be ok to use the 1.6 nozzles in the 1.9 head but it would be better to have the 1.9 nozzles to match the bigger AAZ combustion chamber.
Title: Re: Merc nozzles wrecking a AAZ
Post by: ikas on June 07, 2009, 05:21:35 am
I had a rod  warped because of the nozzles mercedes or who I mounted the nozzles in the injectors. I do not know if the fact that the 10m help! also said that the sb nozzles inject  what the pump can deliver! merc nozzles make the engine sound terrible! I´ve mine merc nozzles on sale
Title: Re: Merc nozzles wrecking a AAZ
Post by: macka on June 07, 2009, 06:35:53 am
Hey monomer, I have a band saw, where abouts "up here" are you?
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 07, 2009, 12:13:38 pm
my car idled and ran great with merc tips.....little smoky yes...but they ran great.

the real question is why would you want bigger nozzles if you don't plan to go over 200hp??? stockers are proven to at least 180hp right??
Title: Re: Merc nozzles wrecking a AAZ
Post by: carrizog60 on June 07, 2009, 05:03:00 pm
I had a rod  warped because of the nozzles mercedes or who I mounted the nozzles in the injectors. I do not know if the fact that the 10m help! also said that the sb nozzles inject  what the pump can deliver! merc nozzles make the engine sound terrible! I´ve mine merc nozzles on sale

can someopne tell me how a nozzle can wap a rod?
or the problem was something else?
thought that bent rods were problems cause by too much boost/fuel at low rpm,valve hiiting pistons etc...
since nobody had that kind of problems other than + smoke?
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 07, 2009, 07:36:28 pm
injectors don't bend rods...... ;)
Title: Re: Merc nozzles wrecking a AAZ
Post by: MJF on June 07, 2009, 11:38:13 pm
stockers are proven to at least 180hp right??


+100hp dynoed.
Title: Re: Merc nozzles wrecking a AAZ
Post by: carrizog60 on June 08, 2009, 04:14:12 am
injectors don't bend rods...... ;)


thats what i thought... ::)
what could cause?
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 08, 2009, 09:11:08 am
stockers are proven to at least 180hp right??


+100hp dynoed.
pretty sure Dave had dyno sheets posted on here with over 180hp on stock injector tips.... I'm sure somebody has it saved somewhere?
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 08, 2009, 09:15:08 am
injectors don't bend rods...... ;)


thats what i thought... ::)
what could cause?
I would want some more specs on the car and what was going on when it happened...that sentence he wrote is VERY hard for me to understand...i'm not trying to be rude...i know hes from Portugal
Title: Re: Merc nozzles wrecking a AAZ
Post by: MJF on June 08, 2009, 09:18:32 am
stockers are proven to at least 180hp right??


+100hp dynoed.
pretty sure Dave had dyno sheets posted on here with over 180hp on stock injector tips.... I'm sure somebody has it saved somewhere?

180hp+100hp=280hp dynoed with stock na/td injector tips.
Title: Re: Merc nozzles wrecking a AAZ
Post by: ikas on June 08, 2009, 10:05:59 am
I´ve a 1.9 td aaz totaly repair and in first run in 2 hours the engine was stooped!
I would also like to discuss this!

thanks
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 08, 2009, 10:27:16 am
I´ve a 1.9 td aaz totaly repair and in first run in 2 hours the engine was stooped!
I would also like to discuss this!

thanks
start a new thread....I'm sure merc injector tips were not your problem...since it was a fresh rebuild I would maybe talk to your machine shop that did the engine work?? or did you talk to them and they blamed an injector??
Title: Re: Merc nozzles wrecking a AAZ
Post by: ikas on June 08, 2009, 11:47:30 am
so!

tey blamed the merc nozzels !

the insider of cylinder have a lot of     coal!

the pistion head dont have mark's
Title: Re: Merc nozzles wrecking a AAZ
Post by: carrizog60 on June 08, 2009, 12:55:32 pm
ikas, i didn't tell on cgp that the only way a injector could cause a bent rod was if he caused the pre-chamber to fall but that will mark the piston for death.
i didn't tell that because i knew that if i would the mechanic would say that was what happened...
now you now why i am arguing with you about that,you were cheated  ::)
Title: Re: Merc nozzles wrecking a AAZ
Post by: RabbitJockey on June 08, 2009, 02:10:20 pm
yeah someone is trying to avoid warranty work.  that or they really are that dumb
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 08, 2009, 02:12:43 pm
so!

tey blamed the merc nozzels !

the insider of cylinder have a lot of     coal!

the pistion head dont have mark's

sounds very suspect if you ask me.....the only way I could see a injector bend a rod was if it some how filled the entire cylinder with fuel and then some how got hydro locked and started......I just can not see any possible way a injector can cause a bent rod.... ???
it's pretty hard to bend a rod...even with super crazy smoky injectors I can't  see how that would bend a rod?? ruin oil and then cause cylinder scoring?? yeah maybe?? but that would still be hard to bend a rod...you would think it would slowly lose power and die if it was oil failure?
BTW my merc tips where smoky yes! but nothing that would consider unsafe...
Title: Re: Merc nozzles wrecking a AAZ
Post by: carrizog60 on June 08, 2009, 03:33:28 pm
the funny thing is that this engine according to ikas only ran 2 hours at idle after fully rebuild...
yes, at idle...
more for me to think that the problem was something else...
Title: Re: Merc nozzles wrecking a AAZ
Post by: 53 willys on June 08, 2009, 03:46:43 pm
the funny thing is that this engine according to ikas only ran 2 hours at idle after fully rebuild...
yes, at idle...
more for me to think that the problem was something else...
sadly I think you are right...someones getting screwed!
Title: Re: Merc nozzles wrecking a AAZ
Post by: carrizog60 on June 08, 2009, 03:57:40 pm
the nozzles on that engine were on my car for about 50.000km and ran great even with SVO.
only a bit of clatter but that was due also from being a mechanical head.
my engine was a 300.000km 1.6d n/a (jk code)that was dynoed at 140hp fly and nothing happened...
theory says its a weaker engine than a refreshed AAZ so something is not right and i think its the mechanic explanation. ::)

ikas bought them from me, and have them clean and pop tested.
fitted them on the engine and started.
engine lasted 2 hours even at idle were there is no load and temperatures like when running hard... ::)