DIY injector cleaning

[Scott Linder]

Bruce Bowling wrote:

> >
> >  Andris,
> > i guess the answer was NO there isnt a GOOD way for the DIY to clean injectors other than a additive in
> > the tank.
> >
> > Jimm L.
> > the injector " guru"
> >
> >
>
> A question:
>
> Could one accomplish a sort of ultrasonic cleaning by simply driving the
> injector coil at a high frequency, like 10 - 30 Khz, while backflushing?
> Seems to me if one got the duty cycle right one could get the pintle to
> just open and close slightly, producing an active high-frequency "hammering"
> on the pintle. This, with the backflushed cleaning liquid under pressure,
> should help clean the unit.
>
> So drive the injector with a 555 timer coupled to a driver transistor. The
> following circuit comes to mind:
>
>   +12       +12                   +12
>    |         |                     |
>    |         |                     |
>    |     ----------             Injector
>   30K    |  4,8   |                |
>    |     |        |            b   |c
>    |-----|7 555  3|----330ohm--- TIP120
>  130K    |        |               NPN
>    |     |6,2 1  5|                |e
>    |     ----------                |
>    |      |   |  |                gnd
>    --------   |  |
>    |          | 0.01uf
>  470pf        |  |
>    |         gnd gnd
>   gnd
>
> The 555 timer is running at 10 Khz, at about 55% duty cycle. The drive transistor
> is a TIP120 Darlington (NPN). Due to the duty cycle, the drive current should
> be fine for any injector 2 ohms and up.
>
> All parts are stocked at Radio Shack, and the whole circuit will cost under $10.00,
> including perf board. This is as DIY as it gets.
>
> - Bruce
>
> --
> -----------------------------------------------------
> <<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> -----------------------------------------------------
>                  Bruce A. Bowling
>                  Staff Scientist
>    Thomas Jefferson National Accelerator Facility
>     12000 Jefferson Ave - Newport News, VA 23606
>                  (804) 249-7240
> bowling at cebaf.gov  http://devserve.cebaf.gov/~bowling
> -----------------------------------------------------
> <<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>
> -----------------------------------------------------

  bruce,

I like the circuit and we will try it at the shop.

????In your injector math program why wasnt fuel pressure factor used ?????


As far as cleaning the injector with the timer.

IF;
The diy wanted to remove the injector from the engine  Buying gaskets seals etc . Some of which are not
available seperate.
And if the cleaning solution was a good product.
And if the injector was properlly placed in a holder etc.
then the timer might work.

Jim Linder
the injector " guru"