Hardeman Motorsport - motorsport parts and diff specialist

323i, Setting Up The K-Jet

For all your questions, problems and DIY stories
Post Reply
e21Keith
E21 Fanatic
Posts: 327
Joined: Sun Jan 05, 2014 7:44 pm
My E21(s): '81 323i Manual

323i, Setting Up The K-Jet

Post by e21Keith » Sun Jun 23, 2019 5:21 pm

First an update. I got the new 731 head on, it's all fitted up and running (just). My reupholstered interior was delivered back to me today ad I am really very happy with it. I'll get it fitted in the next week or two and then I promise some photos.

The engine runs but it just won't idle, actually it didn't idle before I replaced the head either. I can drive it ok and it all seems of but I think it's running really rich. Is there a guide anywhere that explains how to get the K-Jet set up and running from scratch. Apologies if this has been asked before?



shadyracer01
Upcoming E21 fanatic
Posts: 62
Joined: Tue Dec 05, 2017 7:39 pm
My E21(s): 323i '82 Y x2, 1 in resto, 1 now spares

Re: 323i, Setting Up The K-Jet

Post by shadyracer01 » Mon Jun 24, 2019 2:58 am

If you have the coolant heated type air bypass valve still, try fitting that, iirc you have earlier wired version fitted. I serviced my valve and stripped and cleaned Wur, as you say yours runs and drives, I would look at those parts plus check cooling system operating correctly and ignition timing afterwards. To get mine to run sweet I started with high idle speed screw setting and then screw out the mixture adjust anti clockwise roughly 2-3 turns from fully home then lowering idle again. Not had in for mot yet to confirm co settings as desired.
I looked for a set up guide too, but couldnt find so improvised with the above method, hopefully of help to you.

User avatar
Jeroen
Site Admin
Posts: 25854
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: 323i, Setting Up The K-Jet

Post by Jeroen » Mon Jun 24, 2019 9:42 am

Throttle body base setting ok? Vacuum bypass channel and idle adjust screw clean? Aux air valve functional? Ignition timing and vacuum advance ok? Time for a CO meter I'd say.
Regards/groeten, Jeroen

We want your contributions in our E21 Facebook Group! Join, like, post & share!

e21Keith
E21 Fanatic
Posts: 327
Joined: Sun Jan 05, 2014 7:44 pm
My E21(s): '81 323i Manual

Re: 323i, Setting Up The K-Jet

Post by e21Keith » Mon Jun 24, 2019 6:40 pm

I haven't really adjusted anything because I don't properly know what I'm doing....

Yes I have the wired bypass but i checked it was working, I can check again though. As for cleaning I didn't take anything apart, just lots of carburettor cleaner through the throttle body, cleaned the injection pipes, soaked the injectors in fuel for a month, all new fuel lines, new pump, clean tanks...

When you get it to idle by making it super rich you can set the timing which I did, so maybe it's the mechanical idle screw I need to adjust and then go for the mixture. I don't know how long the metering unit sat around for but I have another that may be better.

My MOT station were very friendly, couldn't possibly imagine how they tested the emissions, but it passed.

Actually I can't find anyone with a decent CO meter, the local garage have one for MOT testing, that's all. Seems you don't need to adjust it on modern cars, it's either OK or it isn't!

shadyracer01
Upcoming E21 fanatic
Posts: 62
Joined: Tue Dec 05, 2017 7:39 pm
My E21(s): 323i '82 Y x2, 1 in resto, 1 now spares

Re: 323i, Setting Up The K-Jet

Post by shadyracer01 » Mon Jun 24, 2019 9:44 pm

Out of curiosity can you tell me where the elec feed for aux air valve comes from as I have later type valve on mine?
Ive been in similar situ with my 323, had it running but couldnt get it sweet, had two 37 year old engines and parts to play with, one engine last started 2007, other one 2004 so after stripdown and inspection of ign dizzy, fuel dizzy, Wur, aux air valve and replacing diode relay plus check of time temp switch, cold start valve elec feed, valve timing and clearances, i concluded either vacuum issue or fuel system and control pressure issue. It seemed the culprit was the wur and me creating a blockage by blowing airline through from outside wur port that has gauze filter in it. strip and clean of this and my vacuum issues came good, checked ign timing again (with vac pipes disconnected from jgn dizzy) and found it too far advanced, and when adjusting angle to 22deg before tdc I could hear a positive change in exhaust note and my noisy tappets id checked 3 times quietened down considerably. Also my temp gauge worked better after this, some clues were there, like you i didnt want to adjust things too much either but as I am a former mechanic in no way was I giving up and so admire your bravery in tackling things yourself, Its just knowing what to discount is difficult, but checks need made first, good luck!

User avatar
Mihajlo
E21 Pro
Posts: 542
Joined: Thu Aug 23, 2007 11:07 am
My E21(s): 1982 315swap323i
Location: Croatia - Rijeka
Contact:

Re: 323i, Setting Up The K-Jet

Post by Mihajlo » Mon Jun 24, 2019 9:45 pm

are your injectors okay?

if injectors are leaky, engine will struggle to idle or wil not idle at all...
Understeer is when you hit the wall with the front of the car. Oversteer is when you hit the wall with the rear of the car.
Horsepower is how fast you hit the wall. Torque is how far you take the wall with you.

e21Keith
E21 Fanatic
Posts: 327
Joined: Sun Jan 05, 2014 7:44 pm
My E21(s): '81 323i Manual

Re: 323i, Setting Up The K-Jet

Post by e21Keith » Thu Jun 27, 2019 5:02 pm

I was thinking that the WUR didn't do anything when the engine was warm so ruled this out, if anything it runs better when cold anyway.

The feed for the aux air valve was on both looms that I had, just not used on one of the engines, don't know why that might be?

I don't really know the condition of the injectors, I have a second set so could swap them, all I did was soak them in diesel for weeks before fitting and used lots of carburettor cleaner on them, not entirely scientific!

e21Keith
E21 Fanatic
Posts: 327
Joined: Sun Jan 05, 2014 7:44 pm
My E21(s): '81 323i Manual

Re: 323i, Setting Up The K-Jet

Post by e21Keith » Wed Jul 03, 2019 3:13 pm

Update

I checked the old Haynes manual and followed their very basic description and it now idles, I wouldn't say it idles or runs particularly well but it is now driveable. The main setting that made a difference was adjusting the throttle butterfly.

I'll run it for a while now and see how it goes?

User avatar
Jeroen
Site Admin
Posts: 25854
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: 323i, Setting Up The K-Jet

Post by Jeroen » Wed Jul 03, 2019 10:15 pm

Better! Now put some miles on it!
Regards/groeten, Jeroen

We want your contributions in our E21 Facebook Group! Join, like, post & share!

User avatar
uwbuurman
E21 VIP
E21 VIP
Posts: 15464
Joined: Fri Jun 12, 2009 4:49 pm
My E21(s): 1978 type 1 323i 5speed dogleg Polaris
Location: Ljouwert

Re: 323i, Setting Up The K-Jet

Post by uwbuurman » Wed Jul 03, 2019 11:46 pm

Yeah, and get a co meter before you tweak on it
It's the man next door!

1978 BMW 323i
1980 BMW 528i
1987 BMW 325iA cabriolet
2006 BMW 320d touring High Executive
2015 BMW 320dA touring xDrive High Executive ///Msport

shadyracer01
Upcoming E21 fanatic
Posts: 62
Joined: Tue Dec 05, 2017 7:39 pm
My E21(s): 323i '82 Y x2, 1 in resto, 1 now spares

Re: 323i, Setting Up The K-Jet

Post by shadyracer01 » Fri Jul 05, 2019 4:44 am

Yeah, I found the connector on both my engine looms too, I thought back then when first seen it was for euro spec set up, now it makes sense.
Im still thinking your last adjustment is only masking or compensating an underlier..I dont wish to seem arrogant with that statement, I had saved a link explaining wur function and strip/ repair but it seems to have expired, what I can say is having read that I was then informed enough to remove it and strip down. I have pics I could email you if required. I really thought i had it in pdf form too, have to check old phone maybe.
The trickiest part is not breaking the studs where it bolts to the engine block, with all bolts screwed into alloy, tighten slightly before loosening and good penetrating oil soak too should help avoid breakages.
Once its off, clean externally before taking apart, its not a difficult strip and clean, aerosol carb cleaner,multi purpose grease and cotton buds used on mine and blow out with airline.
The wur is acting as a bleed valve with fuel control pressure, its basically part of the governance of how much resistance pressure is sent to the fuel distribution/ air metering barrel plunger as i understand it, i dont think yours is operating properly and this is affecting the mixture and idle, my symptoms were worse when warmed up, I assume yours is too?
Any contradictions/corrections of my explanation welcome, as I read somewhere once, 'I can teach you, but i cant make you understand'..
I am not a Jenius lol , only here to offer help :screwy

User avatar
Jeroen
Site Admin
Posts: 25854
Joined: Tue Sep 14, 2004 12:23 pm
My E21(s): '81 323i Baur
Location: The Netherlands
Contact:

Re: 323i, Setting Up The K-Jet

Post by Jeroen » Fri Jul 05, 2019 9:52 am

Well I agree to the extent that there is some kind of basis now, but yes it does require a good checking of all settings as Uwbuurman already indicated. Otherwise you may already run into issues as soon as the climate changes a bit (cold start issues for example). The WUR is part of that, you should be able to find more detailed descriptions on this very forum. But basically it makes the engine run richer in the warm up phase. Even when it's stuck this means it should run fine when warmed up.

The connector for the electrical aux air slider is always in the wiring loom, but in later years it wasn't used anymore as they switched to the coolant operated example, but at that point they did not modify the wiring loom so all cars with the non-electrical version have a loose connector in the engine bay.
Regards/groeten, Jeroen

We want your contributions in our E21 Facebook Group! Join, like, post & share!

e21Keith
E21 Fanatic
Posts: 327
Joined: Sun Jan 05, 2014 7:44 pm
My E21(s): '81 323i Manual

Re: 323i, Setting Up The K-Jet

Post by e21Keith » Sat Jul 06, 2019 11:31 pm

I did strip the WUR while I rebuilt everything else, it was quite clean so I didn't investigate too much further. it seems to work, in that the engine starts fine from cold.
The butterfly was completely closed before I made adjustment, the Haynes describes adjusting until it starts to open then go one half turn as a starting point, that's exactly what I did. I don't know the butterfly was closed as the engine it came off I never had running, perhaps someone had adjusted the idle on the cable. Maybe I am masking something else but it now doesn't run so rich when warm, for now I can drive the car so I'm happy.
Of course I now really need a CO meter to make some proper adjustments, then I'll know for sure.

Post Reply