Keihin KS2 Carbs, some details

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Keihin KS2 Carbs, some details

Postby M3THANOL » Mon Oct 29, 2012 8:59 am

Ok, so I rebuilt the original carb that was on the Golf and put it back on on saturday. Got the car running but still no second stage :bang: :bang: :bang: and after that loooooong trek to and from ODI I only managed to get 300km's on R400 of 93 unleaded :fear: . I should be getting 380 - 400km's on R400 93 unleaded so the carb is set WAY too rich!!!! I can confirm this my the little black speck's of carbon on the back of the car. I am guessing it is the float level that is not correct, must be too high thus over fueling!!!. The crap thing is that to adjust the float level I need to loosen the carb from it's mountings due to the space under the rain tray being just too tight to get a screw driver in :bang: :bang: .

I have search the interwebs quite extensively and have not been able to find tuning info or diagrams of the Keihin KS2 carburetor that was put on the cars that came to SA. The Haynes manual only speaks about Pierburg, Solex and Weber carbs :bang: .

I got some tips yesturday at ODI on what to try to get the 2nd stage working again, I will try and see if I can sort it out, but if any of you guys have some good solid info on these carbs I would really appreciate it!!!

I want to get this carb working right until I go fuel injection!!
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

User avatar
JVA
Lieutenant
Posts: 1136
Joined: Fri Feb 08, 2008 8:14 am
Car Make: Seat
Car Model: Ibiza Cupra 1.9 TDI
Membership No: missing
Location: Bloemfontein
Contact:

Re: Keihin KS2 Carbs, some details

Postby JVA » Mon Oct 29, 2012 9:24 am

I also had one of those things on my mk3 when I got it, gave me endless problems. I ended up getting a weber 36 dcd and threw away the keihin carb, the weber is just way simpler and easier to work with and also gives more performance than the keihin.

Is your carb is grounded properly? I remember something about them giving problems when not grounded properly.

User avatar
panic-mechanic
Panic's Place
Posts: 23736
Joined: Mon Jul 29, 2002 9:08 am
Membership No: 79
Location: Benoni, putfontein.
Contact:

Re: Keihin KS2 Carbs, some details

Postby panic-mechanic » Mon Oct 29, 2012 9:34 am

They are not electrical devices so the only issue if not grounded is on idle.
Stephan van Tonder - Jhb - Putfontein Benoni
'07 Audi S6 V10 - beast !!!!!
'05 Audi A6 3.0L TDI Avant
'07 Audi A4 2l TDI
'95 Audi 90 coupe quattro
'13 VW CC 2l tdi (repair project)
'05 Touareg v10
'90 mk2 jetta 2l 16v

Perfect Power dealer. I do dyno tuning.

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Re: Keihin KS2 Carbs, some details

Postby M3THANOL » Mon Oct 29, 2012 9:54 am

yeah my idle is fine, well for a while but I think due to it currently being way too rich it starts to splutter a bit but this is only when at idle and up to temp. I also don't have to use much choke at all when starting it in the morning even with our current cold weather which points to it being quite rich from what I have read. I have an exhaust gas analyzer at home which I will hook up tonight to get a reading in order to confirm my suspicions!!

But as I asked, do any of you what the correct float level is? As a base setting when re-assembling I set it so the float would be horizontal when the needle valve reaches the seat, should I have it set to be horizontal when the needle valve is seated and the spring fully compressed?
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

nd_s
VWCSA Member
Posts: 3352
Joined: Sun Sep 30, 2007 9:32 am
Car Make: Vw
Car Model: 89 Jetta 2 , 03 Polo 05 Polo
Membership No: 1691
Location: Jozi
Contact:

Re: Keihin KS2 Carbs, some details

Postby nd_s » Mon Oct 29, 2012 11:05 am

JohanGP wrote:I also had one of those things on my mk3 when I got it, gave me endless problems. I ended up getting a weber 36 dcd and threw away the keihin carb, the weber is just way simpler and easier to work with and also gives more performance than the keihin.

Is your carb is grounded properly? I remember something about them giving problems when not grounded properly.


Weber 36dcd, I don't like those, Mine fell apart so many times,last straw was when the venturi broke and fell into motor again. But i suppose if it was not for the weber i would not have what i got in the jetta now.


Maybe try speak to ace motorosport in germiston regarding the carb settings.

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Re: Keihin KS2 Carbs, some details

Postby M3THANOL » Mon Oct 29, 2012 11:11 am

not cool hey. No, I am so through with carbs!!!! I just need this car to run right until I do the swap. The unfortunate fact is that I can't seem to find the info I need to set it up and maintain it optimally and the availability of a mechie on the west rand who actually knows what a carburetor is seems to be non-existent!!

Thanks for the lead, I will try an make contact with them
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Re: Keihin KS2 Carbs, some details

Postby M3THANOL » Tue Oct 30, 2012 9:36 am

ok well yesturday I put the GW carb back on as I noticed that the thread for the bolt that holds the air filter housing onto the carb was stripped and the housing was rattling around on top of the carb. I decided to open the GW carb and to my total SHOCK and horror both the 1st stage and second stage jets were loose!!!!!!! Which is obviously why the car was not running right!!

My second stage is now working again as well, I adjusted the little screw that sets the stop point for the second stage when it is closed. I suspect that the reason for me having no second stage was because this little screw managed to work itself out just enough to close the second stage butterfly to the point that the vacuum on the underside kept it closed rather than making it open. The only problem I seem to be having is that the second stage is opening way too late at like 4000rpm. Must I just fiddle around with that screw in order to get the second stage to open quicker?
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

User avatar
mk2-phreak
Captain
Posts: 2570
Joined: Tue Jun 09, 2009 3:34 am
Contact:

Re: Keihin KS2 Carbs, some details

Postby mk2-phreak » Tue Oct 30, 2012 9:54 am

You have far more patience than me WRT carbs. I was just happy my mk2 ran, nevermind if it was fuelling properly ( I was planning to go 2.0 8v FI anyway)

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Re: Keihin KS2 Carbs, some details

Postby M3THANOL » Tue Oct 30, 2012 10:27 am

hehehe, shot man, it was out of necessity, I can't go F.I. until December so I HAD to get it right (well as right as it seems it will be). I nearly cried when I got back on sunday after ODI when I saw that I only managed 300km on R400 fuel, thats BAAAAAAAAAAAD!! Might as well have just driven with a fuel leak, would have been the same result. I don't think even Pitzi's V8 Lumina drinks as much as that hehehehe
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

nd_s
VWCSA Member
Posts: 3352
Joined: Sun Sep 30, 2007 9:32 am
Car Make: Vw
Car Model: 89 Jetta 2 , 03 Polo 05 Polo
Membership No: 1691
Location: Jozi
Contact:

Re: Keihin KS2 Carbs, some details

Postby nd_s » Tue Oct 30, 2012 10:55 am

M3THANOL wrote:hehehe, shot man, it was out of necessity, I can't go F.I. until December so I HAD to get it right (well as right as it seems it will be). I nearly cried when I got back on sunday after ODI when I saw that I only managed 300km on R400 fuel, thats BAAAAAAAAAAAD!! Might as well have just driven with a fuel leak, would have been the same result. I don't think even Pitzi's V8 Lumina drinks as much as that hehehehe



I drove 30 km's and used R500 fuel..Man was i pissed off when my fuel rail broke..
But glad you sorted bud.

User avatar
panic-mechanic
Panic's Place
Posts: 23736
Joined: Mon Jul 29, 2002 9:08 am
Membership No: 79
Location: Benoni, putfontein.
Contact:

Re: Keihin KS2 Carbs, some details

Postby panic-mechanic » Tue Oct 30, 2012 11:05 am

The second stage is operated by vacuum and no setting of screws will make it operate sooner or later. It is directly related to engine load and most of them will not even open when you rev the engine without load. The only correct way to check is under load on the dyno.
Stephan van Tonder - Jhb - Putfontein Benoni
'07 Audi S6 V10 - beast !!!!!
'05 Audi A6 3.0L TDI Avant
'07 Audi A4 2l TDI
'95 Audi 90 coupe quattro
'13 VW CC 2l tdi (repair project)
'05 Touareg v10
'90 mk2 jetta 2l 16v

Perfect Power dealer. I do dyno tuning.

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Re: Keihin KS2 Carbs, some details

Postby M3THANOL » Tue Oct 30, 2012 11:27 am

Yes I know it is vacuum operated and I understand that you need load on it to get it to open thus it doesn't open when simply revving it but my question is then what is the purpose of that small adjustment screw on the GW carbs? I first had it set open too far and as a result the engine was idling at 1700rpm, I wound it back a bit and it returned to the idle set by the idle screw on the first stage butterfly
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

User avatar
Quik-Trix
Lieutenant
Posts: 1317
Joined: Wed Aug 13, 2008 8:24 am
Car Make: VW
Car Model: '84 Mk1 2.0 20v ITB's
Membership No: 3004
Location: Durban/Verulam
Contact:

Re: Keihin KS2 Carbs, some details

Postby Quik-Trix » Tue Oct 30, 2012 11:37 am

I think I know that screw you referring to, it has a small nut to lock it into place? That's the adjustment for the second stage butterfly

User avatar
panic-mechanic
Panic's Place
Posts: 23736
Joined: Mon Jul 29, 2002 9:08 am
Membership No: 79
Location: Benoni, putfontein.
Contact:

Re: Keihin KS2 Carbs, some details

Postby panic-mechanic » Tue Oct 30, 2012 11:40 am

It's called a stop screw and just set the low end of the butterfly so it does not eat into the casing. Nothing more.
Stephan van Tonder - Jhb - Putfontein Benoni
'07 Audi S6 V10 - beast !!!!!
'05 Audi A6 3.0L TDI Avant
'07 Audi A4 2l TDI
'95 Audi 90 coupe quattro
'13 VW CC 2l tdi (repair project)
'05 Touareg v10
'90 mk2 jetta 2l 16v

Perfect Power dealer. I do dyno tuning.

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Re: Keihin KS2 Carbs, some details

Postby M3THANOL » Tue Oct 30, 2012 11:51 am

@ Quick-Trix, thats the one

@Panic, ok, thank you for clearing that up
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

User avatar
markfish888
Cadet
Posts: 494
Joined: Sat Apr 16, 2011 7:45 am
Car Make: VW
Car Model: B7 A4 AUDI & JETTA2
Membership No: 1787
Location: Menlo Park PRETORIA
Contact:

Re: Keihin KS2 Carbs, some details

Postby markfish888 » Sat Nov 03, 2012 7:59 am

Get 2 cans of good quality carb cleaner, and a carb gasket set and a manifold mounting rubber flange.

clean all air channels,main jets inside venturi stacks etc. plus, make sure its correct jet sizes.(105 &115 ???)
basically if you see a hole, spray it!
(wait a minute, that sounds like inappropriate sexual innuendo.. :lol: )


on my mk2 i found low quality fuel hose was the culprit, degrading and blocking everything with very very fine black rubber particals as well as a leaky manifold flange( get more air, run lean, not good)

i've lost the diadram for the propper location of vacuum pipes, (should be a sticker under bonnet) but make sure that is corrcect.

2nd stage @ side of carb directly. I dont run it to air box and then to cold weather flap located in beginning std air box pipe. it is not as cold here as in europe.
test the diaphram for pin hole leaks (i.o.w loosen rod arm from 2nd stage butterfly spindel, suck the damn thing, see it it moves and holds vacuum.)


and the distributor vacuum advance take off is @ back of carb @ CO2 air screw iirc.
make sure no unused vac take-offs from carb is open to atmosphere. some carbs have 2 take offs at the back, some only one.

hope that sorts it!
MK2's dont die, they just get lower & faster!!

Image

User avatar
M3THANOL
Blue Bomber
Posts: 2688
Joined: Mon Jun 11, 2012 12:38 pm
Car Make: VW
Car Model: Golf Mk2...now....2.0L 8V AGG
Membership No: 1822
Location: Jrrrhrrrnrrrsbrrrg
Contact:

Re: Keihin KS2 Carbs, some details

Postby M3THANOL » Mon Nov 05, 2012 7:54 am

hey bud

Thanks for your input. Yeah I serviced the old carb, put it all together and put it on the manifold (didn't replace the rubber flange though as it wasn't torn) the car started pretty easily, just had to set the idle speed but didn't get chance to check the CO reading due to a flipping thunderstorm. Took the car to the drag day at ODI and nearly passed out when I saw the rate at which it was using fuel, WOW!!! The float level was obviously not right. Anyhow, got back from the drag day knowing that the rebuilt original wasn't lekker at all and decided to put the GW one back on because I discovered that the thread in the top of carb that holds the threaded bar that holds the air filter assembly on was stripped :bang: :bang: . Obviously it was just glued in there when the carb used to be on the engine.

I cleaned the GW carb out nicely, was very clean anyway but I made sure all the small ports were cleaned. I noticed one thing however, the thread on the jets in the Keihin carb are more fine than the jets for the GW carb so I couldn't use the jets that I had got to rebuild the Keihin carb in the GW carb. I see what they mean about the GW carbs being generally jetted, the isn't stage jet is a 95 jet and it should be a 105 as far as I know. The second stage is however correct, it's a 120 jet.

The second stage vacuum unit is working fine, no leaks, no blockages that I can find, it is just coming in a bit late at 4000rpm ( like VTEC :wink: ).

I am no longer stressing though, on saturday I paid the deposit on a 2.0 8v AGG motor :troll: so I just need to like with this carb for another month or so then in december it is engien swap time :cool: , I am super stoked for that
I'm literally can't evening!
Image
http://www.iamsecond.com/

Current: The Blue Bomber
http://www.vwclub.co.za/phpbb3/viewtopic.php?f=11&t=151592

1/4 mile: 16.5s @ 133km/h (ODI-2013/10/27)
1km: 165km/h (ODI-2013/10/27)

Return to “N/A Engines”

Who is online

Users browsing this forum: No registered users and 13 guests