Bosch K-jetronic - How to: Modify Your Metering Head

[@BrorAppelsin]

Your videos make me feel like I should grab my spare metering head and start fiddling with it...

[@GreyGooseRestorations]

Do it 👍

[@1.6Kilometres]

Righto. I’m going to give this a go on my 81 Volvo B23e. Going to make my Grandad proud.

[@johnrogers1423]

Fantastic information. Thank-you. Our (DeLorean) fuel distributor does not have any separate adjusters. To adjust the spring for each injector, is it simply a matter of removing the hose to each injector and remove each filter to find a hex adjuster underneath?

[@GreyGooseRestorations]

Hi and thanks, no on that type the internal spring has shims so the flow is adjusted by adding or removing the shims, not easily done

[@johnrogers1423]

@@GreyGooseRestorations Well at least it's possible. Thanks again.

[@heribertmueller9613]

Ingenious idea. Thank you so much for sharing such knowledge.

[@ljuberzy]

that was an interesting part, but now i am a bit confused. what exactly happens with lowered voltage? the pump pressure lowers down, what happens inside the fuel regulator? will it lead to less fuel on injectors, or vice versa, make them squirt easier? (I am trying to explain why the car starts cold with the second attempt in summer, but instantly in winter - probably, fuel accumulator is bad)

[@GreyGooseRestorations]

Lower voltage will reduce overall pump delivery and inturn lower fuel injector output Check if the cold start valve is functioning correctly, it may be a temperature sensor reading slightly off

[@jasonbarron9585]

Not sure why in all my research into K-Jet I've never stumbled across your content. It is excellent, really informative and helps to validate all the reading I've done. I've rebuilt the metering head and WUR (16v variety) on my Mk1, and got it running pretty well. When you are doing your volume tests, are you running your rig with a 'warm' WUR, and what position do you have the air metering plate? Haynes manual for the Mk1 doesn't give per injector volume figures, just says to run until you get 100ml and the others should be within a certain % tolerance. Do you know if there are specified per minute volumes published for the Mk1? Sorry, few questions in there! Keep up the great work.

[@GreyGooseRestorations]

Hi, I use a power supply to simulate a warm environment. Minimum fuel is 120cc/min per injector with the plate lifted 25mm from rest and 20cc/min with the plate at 2mm lift Ideally you want zero imbalance across the number of injectors

[@jasonbarron9585]

@@GreyGooseRestorations brilliant, thanks for the reply, time for some tinkering I think!

[@hadlowwww]

Really useful video, thanks! Curious as to what you use instead of fuel? Last video you said it helps clean and isnt flammable

[@GreyGooseRestorations]

Thanks, i use 80/20 approx mix of fuel and jizzer cleaning fluid

[@ace7821]

Excellent video. What I’ve been looking for my K Jet. Does removing another washer reduce the fuel pressure? My pressures are 105 to 120

[@GreyGooseRestorations]

Hi, yes removing a washer will lower the system pressure

[@ace7821]

@ Do you know roughly by how much, the fuel pressure drops per washer? I bought a rebuilt FD for $1300 and the guy in Sun Valley refuses to believe he tuned it wrong with too high of system pressures, like 120! He never put it in my car to tune it and I’ve isolated everything back down to this nut + washer system. My car will not rev past 600 rpm’s to 2000 rpm’s and the whole system is bogging down.

[@GreyGooseRestorations]

@ace7821 120psi? A 1.0mm shim with either increase or decrease by approximately 0.6 bar

[@ace7821]

@ your help is very much appreciated. You’re awesome. I found removing washers to help quite a bit but still it’s running too rich. The rebuilder put two extra o-ring grommets . I’m going to try removing the outer o-ring rubber grommet. I’m wondering if the FD rebuilder did something in the inside of the FD such as with the diaphragm to make it run too rich?

[@GreyGooseRestorations]

@ace7821 👍 there could be a number of things that could cause the rich fueling, have you adjusted the CO mixture yet?

[@caseytattersall814]

Hi would the shim modification work on a mk1 golf gti ? And do you need fuel pressure gauge, (havent got one to see p.s I) and how many shims would you recommend without using fuel gauge ,is it best to a pressure gauge? And also would the W.U.R modification work looks slighty different , awesome videos thanks for any help 👍

[@GreyGooseRestorations]

You ideally need a set of pressure guages to see whats its going first before upping the pressure. The WUR modification in principle is the same with lowering the control pressure

[@caseytattersall814]

Ok thanks for your help😃 👍

[@1.6Kilometres]

Do you soda blast the iron fuel distributors to clean the rust off the outside?

[@GreyGooseRestorations]

No I do these by hand and then they are bathed in ultrasonic cleaner, to much risk of blocking the control port with any media

[@Hippie9D]

How much or a flow increase can be seen? If a stock CIS topped out about 45/HP per cylinder what will this support?

[@GreyGooseRestorations]

A stock unit once adjusted, will theoretically flow enough to support 200+ bhp

[@Hippie9D]

@@GreyGooseRestorations I'm going to have to find a spare Volvo 240t unit, the six cylinder converted to four cylinder version and give this a try. Could be just the ticket without having to go too far into anything else, thanks! Working on a turbo setup for a VW 8v, but committed to sticking to CIS without resorting to bandaids like the UTCIS

[@volvotommi]

one of my metering heads injector port starts to give fuel sooner than others. non adjustable head. is shimming the spring way to go? i have also metering head from bmw with adjustment screws. it also was too anxious to start spraying. i have to build bench. do you use diesel as test fluid?

[@GreyGooseRestorations]

Yes with the non adjustable ones it's a case of shimming the spring internally, no I use a specific calibration fluid for petrol based units

[@MatthewCoxall-d4s]

You have really helped me understand how my KR works. I’d still worry about splitting that metering head though! By increasing fueling as you do is MPG dramatically reduced?

[@GreyGooseRestorations]

Thanks, not much to be honest, obviously full throttle applications will use more but if all else is well and set to optimum for the engine you won't notice much

[@sergeilosev1416]

whats different beetwen KR/9A engines

[@GreyGooseRestorations]

KR is 1781cc (1.8ltr) and the 9a is a 1984cc (2.0ltr)

[@jaecalderon260]

These videos remind me how over engineered the r129 is… just sooo many points to check if they are doing their jobs correctly and not only the ke jetronic … but all the other points of failure…. I have a super rough idle that sometimes levels out . But mostly it’s misfiring and stalls if I give it throttle … don’t know where to start… I replaced the cam and crank sensors. Nothing. Going to do the temp sensor , coolant temp sensor and temp gauge sensor this week. Then rotors and caps wires and plugs …. If that 500$ doesn’t fix it then on to fuel system … and potentially 1500$ for pumps, filter accumulator , regulator… hopefully I don’t have to touch the injectors and seals… I did a vacuum carb cleaner test and no leaks I could find…

[@ramarakeshv]

Fantastic mate

[@GreyGooseRestorations]

Thanks

[@bedo953]

Hello! could you tell me an approximate value of the amount of fuel for a Kr engine? for example, how many deciliters should there be in 1 minute at full throttle?

[@GreyGooseRestorations]

Book figures state 120 cc/min (1.2 deciliters) when rebuilding and flow testing metering head for 16v KR i set them at 140 cc/min (1.4 deciliters)

[@bedo953]

@@GreyGooseRestorations Thanks

[@predraglukovic7733]

What a genius👍

[@GreyGooseRestorations]

Thanks

[@mcfly6667]

Garage light must be CIS-E ...

[@GreyGooseRestorations]

😅