Thread: CIS fuel head
View Single Post
Alan L Alan L is offline
Registered User
Alan L's Avatar
Join Date: Apr 2006
Location: New Zealand
Posts: 3,247
I made up the constriction piece since it was about as much work as pulling the fuel head off. So in the overall context of the saga, seemed worth a shot. There is a pic showing it inserted in the fuel head connector to the WUR line. I can pull it out with a magnet - it is a nice clearance fit.(or unscrew the union from the head).
The plate flutter definitely diminished with this in. Not gone completely, but much less violent (my size of constriction of course is a complete guess - I don't know how small they are in other CIS heads - never having dismantled one) . But I still had an issue with the fuel system - still pissing too much fuel. So pulled the head out again and split it again. Same problem - had torn one of the elongated O rings again. So, back to the drawing board. I am going to reassemble it a different way this time. I have separated the metering chamber from the body (left it attached last time - don't disturb anything you don't need to). I have scribed a couple of reference points where particular slits need to line up with injection holes in the body. I intend inserting the chamber while I can inspect all the O rings going in. Then insert the head (base) back on to the chamber.
I will post all my success and failure here so others can use the experience - or just treat it as cheap entertainment.
I may be speaking too soon, but I suspect there is nothing too difficult about this beast. But it is now Sunday and I don't have any more spare O rings.
Will keep you posted.
The one thing I regret in dismantling it, is not tracking each spring to its own chamber. The secret to setting these up to really perform is matching all the flows. Otherwise all your tuning figures are just a rough average rather than precise optimum. I may have disturbed that - assuming the previous monkeys who have worked on this car were even vaguely aware of this. It may be a need for recalibration of the injectors again. The allen head screws on top of the head by the injectors seem to alter the spring pressures, so it can probably be done in car.
What I would like to do is get the head running again, with my restrictor in and fiddle with the pressure on the extra component in my line. Between the two of them, I may be able to stop these spasms. Meantime I will try and organise some sort of fuel line that will let me bypass the mystery component and see if it all cures itself.
Meantime, I need to get a few other things around the place. I've spent about 200 hrs on this beast in the last month or so, travelled about 3 km in it, and it still sits on jack stands.
Old 12-01-2007, 07:51 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #22 (permalink)