broken cc gear that drives injector pump on ZD30

[krawczuk]

HI, been fixin up a navara zd30 turbo. noticed the c mark on injector pump gear and the other cc mark out by 1 tooth, tried to align the marks so that the c is inbetween the cc , but the gear with cc stamped on it turns about half inch or so either way , but the rest of the gear stays as is.

the cc gear has two grooves in it , its the outa thin section that turns,.
is this normal or has it broken ? look at the pic and you can see that the outer part is missaligned with teh rest of the gear.

mark k

 

[tweak'e]

i think thats the idler gear. i read there is an internal mech, possible a spring. there is a procedure in the book so its locked before its removed.

 

[tweak'e]

just having a read up on that.
i suspect all the gears are full width (idler main, pump).
the inner and outer gear of the idler gear is probably for noise reduction. it should be out of alignment when installed. i think the idea is that one part is spring loaded and its teeth hit the other gears teeth first. as its spring loaded the load comes on gently and allows the main part of the idler gear to contact smoother ie soften the blow.
most likely due to the sudden load the injection pump places on the gears when its fires. it takes a lot of force to fire that amount of pressure.

 

[Resto]

yep its a three piece gear, the manual explains about putting in a locking bolt BEFORE removing the pump gear. ( changed mine a few weeks ago.) the C's will only line up when its TDC, the pump gear is a different diamater (there is a name for this, but cant remember what it is) so you have to keep tuning the engine over until they line up, if you need to.

 

[krawczuk]

yep its a three piece gear, the manual explains about putting in a locking bolt BEFORE removing the pump gear. ( changed mine a few weeks ago.) the C's will only line up when its TDC, the pump gear is a different diamater (there is a name for this, but cant remember what it is) so you have to keep tuning the engine over until they line up, if you need to.

???? mmm you mean useing a 6mm shaft to lock the injector pump gear ? how does that affect the idler ?

or do you mean take the cover of that covers the idler pulleys/ ballance gears etc,,,,,, and put the pin in the gear with the double cc on it ? to lock that ?

any help appreciated....lol

mark k

 

[Hatchy]

No it's a bolt and it's the center that's spring loaded. It took 2guy's with it on the bench to wind it back up.

 

[tweak'e]

???? mmm you mean useing a 6mm shaft to lock the injector pump gear ? how does that affect the idler ?

or do you mean take the cover of that covers the idler pulleys/ ballance gears etc,,,,,, and put the pin in the gear with the double cc on it ? to lock that ?

any help appreciated....lol

mark k

afaik take the covers off and screw in a 6mm bolt into the idler pulley to hold it all together. otherwise it can come apart and is a nitemare to put back together. (nissan says the idler is unusable if it comes apart).

 

[krawczuk]

getting there ( zd30 injector pump gears..)

hi, thanks for ALL YA help, finally worked out what i had to do. wish i knew about taking the plug out and putting the bolt in thru , there BEFORE I took it apart , i knew about the bolt in the injector pump gear but not the " c c " idler.

mark krawczuk