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Making a test setup for the K-jetronic fuel system

 
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Dutch924-racer  



Joined: 23 Jul 2007
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Location: The Netherlands

PostPosted: Sun Jan 15, 2017 8:07 am    Post subject: Making a test setup for the K-jetronic fuel system Reply with quote

I making a test setup so I can adjust/ equal the flow to the injectors.

I have a Bosch pressure gauge which I have to fit, but I have to make an adapter for it first.
I also want to add a wire to the wur so it can warm up

When pushing the meteringhead plate down, it works for a few seconds but then it stops spraying fuel, what am I doing wrong ?


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Fasteddie313  



Joined: 29 Sep 2013
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Location: Not Detriot - NMI

PostPosted: Mon Jan 16, 2017 3:41 am    Post subject: Re: Making a test setup for the K-jetronic fuel system Reply with quote



I could see that happening if you were just spraying off the rest of your residual pressure but I think that's unlikely since your FP is right there with wires on it..

You do have your FP running full time and your return to tank lines are constantly flowing correct?
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Dutch924-racer  



Joined: 23 Jul 2007
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Location: The Netherlands

PostPosted: Mon Jan 16, 2017 5:10 am    Post subject: Reply with quote

Fuel pump is constant running and got a return line bak into a smalltank

maybe the fuelpump is bad, have to hook up the pressure tester first
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Dutch924-racer  



Joined: 23 Jul 2007
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Location: The Netherlands

PostPosted: Tue Jan 24, 2017 6:51 pm    Post subject: Reply with quote

hooked up the pressure gauge, the pressure drops when you put down the plate in the air flow meter.

Could this be because I don't have the accumulator in the set-up ?
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937 DITC
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Forge recirculation valve + boost controller
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Rasta Monsta  



Joined: 12 Jul 2006
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PostPosted: Wed Jan 25, 2017 2:24 am    Post subject: Reply with quote

Is the pump gravity fed? Accumulator shouldn't effect volume.
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Fasteddie313  



Joined: 29 Sep 2013
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Location: Not Detriot - NMI

PostPosted: Wed Jan 25, 2017 5:56 am    Post subject: Reply with quote

I could see the accumulator helping dampen pressure spikes and dips but it should have no effect on overall flow..

You can do a FP flow test as per the manual..

Maybe it could be the system pressure regulator in your FD sticking if not the pump? The plunger thing on the side, you can take it apart and clean it but be extra very areful with the plunger and its bore so you do not scratch it even the tiniest amount, precision surfaces etc..

You say the pressure drops right? How?
Does it just dip a little bit and come right back up?
Does it drop down to a lower pressure and stay steady while the injectors run?
Does it just drop to zero 0 ?
Did this system work ok before you put it into this test setup?
Is it possible you have your main feed and tank return lines backwards?
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1980 931S - LSD - FMIC - GTS fuel - hobby
95 M3 manual coupe - summer DD
06 X5 3.0 auto - winter DD
01 RS25 coupe - 90% Retired
06 MDX - bought for mom to DD
81 Rambler BBC 454
97 Tercel long retired/sitting
77 gs750 - 95 300ex - 89 blaster
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Dutch924-racer  



Joined: 23 Jul 2007
Posts: 1002
Location: The Netherlands

PostPosted: Wed Jan 25, 2017 7:22 am    Post subject: Reply with quote

pump is not gravity fed, could this be a problem ?

Eddy, I have to check again to give you an answer

Is this correct ?

1- fuel pump fed
2- WÚR out
3- fuel return
4- cold start valve
5- Wur in (large hole)
6- injector 1
7- injector 2
8- injector 4
9- injector 3


_________________
937 trackday car
Series 2 engine
951S turbo and intercooler
937 DITC
Fast road camshaft
Forge recirculation valve + boost controller


Last edited by Dutch924-racer on Wed Jan 25, 2017 7:43 am; edited 2 times in total
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Fasteddie313  



Joined: 29 Sep 2013
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Location: Not Detriot - NMI

PostPosted: Wed Jan 25, 2017 7:35 am    Post subject: Reply with quote


_________________
1980 931S - LSD - FMIC - GTS fuel - hobby
95 M3 manual coupe - summer DD
06 X5 3.0 auto - winter DD
01 RS25 coupe - 90% Retired
06 MDX - bought for mom to DD
81 Rambler BBC 454
97 Tercel long retired/sitting
77 gs750 - 95 300ex - 89 blaster
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Dutch924-racer  



Joined: 23 Jul 2007
Posts: 1002
Location: The Netherlands

PostPosted: Wed Jan 25, 2017 7:46 am    Post subject: Reply with quote

I got the order of the injectors wrong, but thet shouldn't be a problem I assume ?
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937 trackday car
Series 2 engine
951S turbo and intercooler
937 DITC
Fast road camshaft
Forge recirculation valve + boost controller
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Carrera RSR  



Joined: 08 Jan 2010
Posts: 1545
Location: Somerset, UK

PostPosted: Wed Jan 25, 2017 9:09 am    Post subject: Reply with quote

Dutch924-racer wrote:
I got the order of the injectors wrong, but thet shouldn't be a problem I assume ?


Doesn't matter on a continuous injection system
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Then www.924board.org/viewtopic.php?t=31252
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Rasta Monsta  



Joined: 12 Jul 2006
Posts: 11353
Location: PacNW

PostPosted: Wed Jan 25, 2017 1:50 pm    Post subject: Reply with quote

Dutch924-racer wrote:
pump is not gravity fed, could this be a problem


yup
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