K-jetronic?? Any experts? Is there any form of adjustment?

Will be having a tinker with an K-jetronic car and was wondering if there is any facility for mixture adjustment?

I haven't got a clue when it comes to mechanical fuel injection!

 

Which mixture do you wish to adjust?

 

Reading these 2 lines, should we be telling you

 

Agree with Ryan

Dont tinker about if you have no idea and need to ask questions regarding "how to"

Take the car to a tuner and let them adjust what is needed or you could make it a wholelot worse.

If you do adjust it how are you going to check its correct?

 

k-jet (ie XR3i) nothing really user-serviceable.

you can change the mixture at idle, thats about it.

 

I beg to Differ Jim

 

With my innovate LM1.

I'm not new to mapping fuel injection just working with mechanical injection!

 

The main problem i find with them is that the plunger plate drops, it should sit level with the bottom of the housing but usually sags lower. they can be adjusted back level by tweaking the metal support under neath the unit. always seams to smooth the idle out.

 

Do a search on the net for shimming the bosch K fuel pressure reg.

Save my fingers

 

ok stu, try not to give the game away and tell me what i'm missing, but lead me in the right direction instead

i cant see any other adjustments possible, the screw is only adjusting the rest height of the metering head and the metering head has no other adjustment on it, so it aint there. The only other thing i can think of thats going to adjus the mixture is the warm up regulator, but this doesnt have anyadjustment on it either? surely you'd have to mdify the ammount of vacuum etc. getting to the WUR in order to modify the mixture? or you'd have to change the profile of the metering head trumpet?

 

bollocks you git you gave the game away too easy

surely adding shims etc. is hardly user-serviceable? ie there's no screw to turn and it aint listed in the haynes manual :P

also if you shim the fuel reg, are you adjusting the base fuel pressure?

 

Jesus christ.... do you guys on here never do anything to your own cars!

How are you ever going to learn anything about your own cars if you do take the initiative, do some research, learn and put into practise.

Are there no real petrol heads on here!

All i bloody hear on here is "my tuners better than your tuner"!

You should devolop your knowledge and skills, work on your own car as far as you can so you can be proud of something you did... not just payed for!

 

garage19, ive got the K-JET manual thingie from bosch SOMEWHERE on my home PC, catch me on MSN later (galballyj@hotmail.com) and i'll sent it over. it's in PDF format and will tell you everything you should ever need to know about K-JET.

ps if anyone's the the manual on KE-Jet then i'd love to have a read

 

I changed a wheel a few times... I'm getting better at it

I'm not at all mechanically skilled and cause more damage than good, engines and stuff for my cars are expensive things! so I leave it to my 'tuner' (he is better than yours by the way )

I do the same with my body. I'm not a doctor and so when I need an operation, I don't try and have a go myself and see how I get on, I go to an expert.

and I am pretty confident I am as big a petrol head than you!

 

Mr Galbally,

Thankyou!

That should help.

You have PM.

 

Your Welcome Pal.

 

Ok, fair enough.

But why criticise someone who is mechanically minded just because they do wish to teach themselves and do their own work?

Thats all that seems to happen on here.

I really enjoy taking on a new challenge, picking up some new skills and learning a little more.

I'n the past I've designed and built a new swing arm and rising rate linkage for my old race bike, built my own turbo conversion for my old road fireblade, made and run my own nitrous kits (with out melting anything), turbo charged and mapped an M3 turbo, Zetec turbo and helped map a turbo bike. I prolly don't know half as much as some of the pros on here (stu, karl) but i learn as i go and get real pleasure out of it.

I'm sure working with K jetronic will not phase me that much... as long as i can get some info to help me in the first place.

 

Are my posts invisible on this topic?

 

Who said that?

 

who said what rich?

 

I wonder why i bother helping anyone at all at times

 

Don't worry Stu, some of us -are- listening

 

Thanks Chris

 

yes thanks

KE jet rocks

 

ricj, send it over

 

The K jet can be adjusted/modified

System pressure.

This pressure is determined by the primary pressure regulator, situated within the metering head.
When the required pressure is obtained, the plunger within the regulator lifts off its seat and excess fuel is returned to the tank.
This system due to the nature of its operation will automatically compensate for different fuel demands under different conditions. For example if the fuel requirement is low at engine idle, the plunger will lift and return a greater volume of fuel back to the tank than when the demand is higher, when a smaller amount of fuel is returned.
When the engine is switched off, the fuel pump relay looses the coil negative signals that energise it and the voltage to the pump is removed: this subsequent loss of pressure will cause the primary pressure regulator to close. This action subsequently blocks the return flow to the tank and helps the accumulator to maintain pressure in the system.

The systems pressure is determined by the tension of the spring reacting against the plunger, if a higher pressure is required, small shims can be placed behind the spring, changing it's effective length and increasing the pressure. A shim of approximately 2 mm will increase the pressure by about 10 psi

Warm up regulator is responsible for the system control pressure.
The control pressure is tapped off from the primary pressure circuit in the metering head's lower chamber through a tiny restrictive hole which gives it the ability to differentiate between the two pressures. A flexible pipe then connects the control plunger gallery to the warm-up-regulator and returns back to the metering head to a connection next to the primary pressure regulator's transfer valve. This valve is in the circuit to close the fuel from the control circuit when the engine is off, avoiding the total loss of system pressure while the engine is stationary

The input to the warm-up-regulator flows into a small chamber in the top of the unit, its return is through a small drilling and back to the metering head. By controlling this return flow it will cause a change in pressure acting on the top of the control plunger. With a cold engine the flow must be fairly free giving it a lower pressure. This will allow a higher lift of the plunger which in turn will enrich the mixture under these conditions. The free flow is obtained by the internal bi-metalic strip exerting a downward pressure on the spring which decreases the pressure acting upon the shim, this lower force allows the fuel to flow almost uninterrupted
The best way to change the pressures is to replace the warm up regulator with a sepertate pressure regulator, that way you can adjust the pressures, on my race car the standard fuel pressures are not enough to allow the car to rev past 6000

Here is a web site that may help you understand the system a little better.http://www.auto-solve.com/mech_inj.htm#top

 

Am I right in thinking that the K-jet Warm Up Regulators used on some Saab turbos could take a manifold pressure feed and adjust the fuel pressure based on that? Effectively acting like a Rising Rate Fuel Reg?

 

I was listening Stu and found your post about Shims and stuff very interesting.

A Shim is one of those women with a fellas private parts isn't it?

I'm going outside to build one of those engine things, I've been trying to forge some pistols but I can't get the watermark right.

 

We supply a three stage warm up reg, which has positive fuel enrichment if used with a turbo, and has an adjuster in its base for tweaking!