Carburettor K124

[Yurgen]

the little information I found on the K129 is that it is a carburetor coming from generating set. There is no "recovery pump" inside and consumes fuel in a way that the environmentalists get angry

[Geronimo]

Yeah, I followed the German story with the "ghost carb K22Ж". They needed quite some time to finally find one and also in Poland I never saw this carb. Since these engines were (nearly) all exported, it's also useless to search for them in Russia.

And anyhow, I like these 124's. I will check today, but as I remember, the foot of my K124D has a 38mm borehole which would rather indicate the use on a 2,43l engine, contrary to the info of Krys.

[krys80]

Ok, I found back that the K22D has a main jet producing 220cm3/min, where the K22R is giving 315cm3/min. All other parameters are more or less the same. If this is analogue with the K124 series, I can forget to put my K124D on the 2,43l engine of my Gaz69M from 1968.

You are wright - it is analogue with K-124 series.
In basic words ....what you can, and what you can not do.

You can all the time fix carburettor K-22D / K-124D on engine 2430cm, and it will work perfect (of course if carb would be in fully working order).
Consequence of it will be two
- lower fuel consumption.
- generally less power / in some situations engine will behave a little different.

You can not...or it is not recommended to use K-22R / K-124R in engine 2120cm3 because engine would be flooded by fuel, problems with starting up (flooded / wet spark plugs).

In polish army instruction for gaz-69M with engine 2430 is mentioned that for this car can be used carburettors: K-22R, K-22D....
Generally original K-22R was not popular amoung polish soliders, if it was possible this carb soliders changed to K-22D, or G-35 - carburettor for Warszawa (polish version of russian GAZ-M20), sometimes soliders put smaller jest too....everything because of petrol .
As far as I remember for gaz-69 polish army used this calculation 18l petrol / 100km. If driver used more, he paid for it from his own pocket, in polish army ,,slang'' it was called PRZEPAL.
But with carburettor G-35...especially with reworked smaller jest = no penalties, and some petrol even left...and left petrol illegally soldiers traded, or used in their own cars .

Camming back to yours carb K-124D, (by the book....from factory your gaz received K-22R- and only this would be fully original for orthodox) if you want to have a full power from 2430 engine...just change jets in your K-124D from smaller to bigger like in K-124R. After that K-124D with jets like K-124R will be genarally allmost like K-124R.

[iannima]

Hello Krys, nice story

...however...
I must report that I have had a K22R fitted to my 2.12 engine for the last three years (possibly more). I only took it off a couple of weeks ago. In this period I have done something like 10,000 Km and I can report fuel consumption in the region of the magical 18 litres per 100 Km you mention if not less (with obvious variations). My spark plugs have not been wet with petrol or flooded, and I have had no trouble starting the engine because of flooding. (Any minor instance of flooding I have had over the years, has been because of the distributor not working, never because of the carb). And then the point of the K22 is that one CAN regulate the richness/weakness of the mixture, which would certainly affect fuel consumption measures, half a million other things being equal (which they never are).

So I am afraid I find it difficult to believe that the difference could be as clear-cut. Could it be that these Polish soldiers did not know/ could not be bothered to learn how to regulate (or repair) a K22 carb and the G35 was easy to come by?

[Geronimo]

Camming back to yours carb K-124D, (by the book....from factory your gaz received K-22R- and only this would be fully original for orthodox) if you want to have a full power from 2430 engine...just change jets in your K-124D from smaller to bigger like in K-124R. After that K-124D with jets like K-124R will be genarally allmost like K-124R.

A factory delivered Gaz 69M or AM should have been delivered with a K22R, that is correct.

Let's forget for now about the idle and the acceleration jets.

The K-22R carb has a main jet with a capacity of 315cm3/min and an additional jet (compensation jet as mentioned in the Polish manual) with a capacity of 225cm3/min. Both jets are combined in one jet block and work together. The main jet can be regulated from 0 to max. My conclusion is then that this carb can work in the area of 225cm3/min until 540cm3/min depending on how the main jet is regulated (please correct me if I'm wrong).
The K-22D carb (standard delivered with the Gaz 69 equipped with the 2,12l engine) has resp. jets of 280 and 220, so it can work in the area of 220cm3/min until 500cm3/min

Now, my K-124B (I was wrong with the D index) has only one main jet with a capacity of 370cm3/min and can not be regulated but is mentioned in the UAZ 469 spare parts catalogue as the carb for the M21 overhead valve engine of 2445cc.

Of-course, what the jets can deliver is something else as what the carb will deliver and how. Then, we're back at rpm's, vacuum, sections, speed and flows where some mysteries remain unsolved like the different manifold boreholes and plenums although the carbs K-22D and R both run through a 33mm outlet and the K-124B (as also the K-22Z) have a 38mm outlet.

I really wonder if these K-124D's or R's are so different in their jetting that they can not work on the other engine, I rather believe that the differences are model related such as the orientation of the foot or the type of fixation of the air filter.

In my opinion, and on condition that I didn't make a wrong assumption, all of these carbs will work on all of these engines. With the 22 series, it is a matter of correct regulation and with the 124 series you get what you have but the capacity is sufficient.

[iannima]

In my opinion, and on condition that I didn't make a wrong assumption, all of these carbs will work on all of these engines. With the 22 series, it is a matter of correct regulation and with the 124 series you get what you have but the capacity is sufficient.

This makes a lot of sense to me and the argument on the jet size clarifies something I had not understood yet Thank you.
Commonality and inter-changeability of parts obviously makes sense as a military requirement in all countries. But I would add that the engineers designing these engines and carbs in the Soviet Union would also have been concerned by the production bottlenecks that plagued the system. These often prevented the factory from meeting the output objectives of the production plan, with all manners of dire consequences for the managers/engineers. So it would have been very much in their interest to have substantially inter-changeable carbs...

[Geronimo]

Another reason of moving away from adjustable carbs was, most probably but paradoxically, engine damage and fuel consumption.

Although the fact that, with a correct tweaked carb, one can save fuel and get the most out of the engines performance, most users of these vehicles were no experts in carb adjustment (I can count myself also into that group). Therefor most vehicles were running or to lean (heat issues) or in most cases to rich (high fuel consumption) because the thinking of an ordinary soldier is "more fuel gives more power". Hence the story of Krys where soldiers were forced to pay for over-consumption themselves.

With a non-adjustable carb like the K-124, there was already one thing less that could be set wrong.

[duncan]

It would be useful to have a list of main jet sizes per carburetor model here. I already rebuild our k124 so dont feel like re-opening it, but I have a k22 rebuild kit laying around. Will check and post the main jet size on that when I get some time to check it, unless one of you beats me to it.

[Geronimo]

Unfortunately, we don't have this for other K-124 types.

Please note that in the table of the K-22 series, the K-22P(R) is listed as a carb for a Gaz M20 (the smaller side valve engine) although it is mentioned in several manuals as belonging to the Gaz 69M which has the bigger side valve engine M21b. Most probably this mistake was caused by the fact that it still has a 33mm outlet whereas the manifold intake opening changed to 38mm on the bigger engine.

[iannima]

Geronimo and I have been exchanging emails about these carbs and I think some of this should be shared more widely... In the first instance there are two diagrams that Geronimo has managed to find about the K124B which is the version intended for the earlier models of the Uaz 469.
a cut out:

and a scheme of its working (unfortunately the green overlay cannot be taken off)

Geronimo has identified the different phases as follows:
1. Cold Start (choke) conditions, the upper left diagram
2. Idle conditions, the lower left diagram
3. Normal (partial throttle) conditions, the middle diagram
4. Full load (full throttle) conditions, the upper right diagram
5. Acceleration conditions, the lower right diagram

As you can see the difference with a Gaz 69 carb, is the wrong orientation of the foot (with the studs parallel to the direction of travel), and the round connection to the air filter on top. I have ventured an hypothesis that seems plausible to me: that this diagram for the K124B is MOSTLY applicable to the Gaz 69 carbs of the K124 series, because what they probably did is to have the MIDDLE section of the carb (i.e. the main one with the venturi, float and the jets) identical for both Gaz 69 and Uaz 469 (except possibly for jet sizes); whilst the foot and the top would be different in order to match the different manifold studs and air filters. This is consistent with interpreting the K124 as the later development introduced to the Gaz 69 in the years when they were equally fitting other elements of the 469 to the older model (axles; brakes; exhaust silencer etc.)

[Geronimo]

I agree with Matteo concerning the construction of the carb in three parts where two of them are exchangeable to fit the needs.
I also found out that the values of jet flow (cm3/min) are related to the amount of water which flows through the jet in a time span of one minute with a static pressure of 1 meter water column at the other side of the jet. They have nothing to do with the actual fuel flow and are for calibration reasons only. Of- course they do tell us something when we compare one jet with another.

Then, I went a little bit further by comparing the functioning of the K-124 carb with the K-22 carb. Here under the working scheme of the K-22 carb. The set up is the same as the scheme of the K-124 here above;



Few things are worth mentioning;

1) The two jets (main jet (adjustable) and compensation jet), joined in the main jet block of the K-22, are always working, or not working, together. At idling, both jets are not working.
2) The idling jet of the K-22 works only at choke and idling conditions, not during acceleration or under load. Whereas the idling jet of the K-124 is working under all conditions.
3) The acceleration jet of both carbs works the same way.
4) The main (non adjustable) jet of the K-124 works or doesn't work as the main jet block of the K-22, meaning always working except at idling.
5) The K-124 has an additional "economizer jet" (nr.8 and 9 on the scheme of the K124) which the K-22 doesn't have. This one works only at full throttle according the scheme, but the description says that it kicks in automatically from 1700-2000 rpm and keeps on working until full throttle.

So, the capacity of the K-22P(R) compared to the K-124 is as follows:

At idling: K-22P(R); 52cm3/min. K-124: 55cm3/min (both adjustable)
At normal load: K-22P(R); 225cm3/min until 540cm3/min (adjustable). K-124: 55+370=425cm3/min (not adjustable)
At full load: K-22P(R); 225cm3/min until 540cm3/min (adjustable). K-124:55+370=425cm3/min + economizer jet (?cm3/min) (not adjustable)

Unfortunately, I didn't find the capacity of the economizer jet in the K-124 to come to a comparable figure but I think it is clear that both carbs, although their way of working is quite different, are calibrated so close together that they will both work as intended on the 2,43l engine and can work also on the 2,12l engine (for this, one has to do the same exercise with the K-22D carb).

[krys80]

I can not remember when the last time I have seen carburettor K-124R for sale...three...or four years ago probably...but here someone is selling it:

http://allegro.pl/gaznik-k-124-gaz-69-i4244686165.html

I have this kind as a spare, so I do not need to buy more...but may be someone does...and it is occasion to do it. Price is attractive too for this very rare model I think.

[iannima]

Just fitted . And it does fire the engine . it remains to be seen how it "performs" on the open road... even though "performance" and GAZ-69 should not really be used in the same sentence... I am indebted to a Genossse who alerted me to the existence of this advert: http://hmvf.co.uk/forumvb/showthread.php… I met up with Tim at Stoneleigh and also bought a Dynamo and the windscreen wiper mechanism, which seems to go for insane prices on the continent. .




I have not fitted the Dynamo and have no immediate plans to do so, unless the DDR one shows signs of not being at its best any more, but here it is:


Tim has other bits and pieces (e.g. a UAZ469 carb and alternator and two GAZ-69 distributors) which apparently came to the Cobbaton Combat Collection in '92 with some UAZ 469s that they imported from the Czech Republic. It's all brand new and shiny... but obviously with Russian stuff, that does not mean much...

[iannima]

We have said it before, but I think it should be repeated again and again .. that one should NEVER trust anything to work just because it is new and shiny... I'm afraid it applies to my new carburettor K124 too . Firstly I found that it was flooding which was duly explained by the O ring on the needle having dissolved in modern petrol. So from a certain point of view that had to be expected. When I took the carb off to open it up and fit the rubber ring to the needle valve, I noticed something odd... The accelerator pump sprayer was MISSING This is number 32 in the diagram below:

As you may recall I have another K124 that never fired the engine, so a bit puzzled, I plugged the hole in the new one cannibalising the old one for parts. I believe this is a very Russian and Socialist practice... It probably is very military too under ANY flag...

However... things were still not right and I knew it. Somehow I did not manage to accelerate smoothly... So I started wondering whether my own new K124 had not been cannibalised for parts at some point in its Socialist life. In the end I had no option but to take it off and refit the old K22R to the vehicle to keep it mobile. I did that this morning.
This afternoon I took both K124s inside and opened them up to have a look around... On the left is the shiny new K124 that DOES fire the engine but does not accelerate very well, on the right is the old one that has never fired the engine no matter what I tried...



Now... if I am not completely mistaken... I think that the new one is missing the return spring in the accelerator pump...

[iannima]

If you look at the pistons that form the accelerator pump, the middle one on the right has a spring that brings it up again once it has plunged, the one on the left has nothing . It will still be pulled up, but not smoothly, by the various springs that pull down the throttle linkage connected to the accelerator pedal. Am I right in saying that this would make acceleration not impossible but very jumpy and uneven?
I am not clear how I am going to swap these parts over...

[iannima]

Derek confirmed that a spring must be missing and its absence would explain quite a bit of the jumpy constrained acceleration that I was experiencing . By the looks of it, the spring probably has been missing since the day the carb was assembled at the factory Because swapping over the other one implies dismantling quite a bit in both carbs, we are going to try and feed a spring from the top and cut it to size... Oh well...

[iannima]

Found a scheme without the green overlay

Geronimo has identified the different phases as follows:
1. Cold Start (choke) conditions, the upper left diagram
2. Idle conditions, the lower left diagram
3. Normal (partial throttle) conditions, the middle diagram
4. Full load (full throttle) conditions, the upper right diagram
5. Acceleration conditions, the lower right diagram

[iannima]

And let's bring here what Dave has discovered about the acceleration pump...

It has three circuits: (separate jetted fuel pathways)
1) Slow speed idle circuit (used at idle up to about 500 rpm, and blended with the slow speed idle screw on the side of the throttle body base)
2) Mid range circuit (used mid throttle up to about 1500 rpm, fixed - non adjustable)
3) High range circuit (used at above 1500 rpm to wide open throttle, and is adjustable on the top of it's actuation plunger attached to the accelerator pump assembly)
And then there is the accelerator pump, which is not jetted, and is adjustable (it does have a check ball however) which I guess one could call the "fourth fuel circuit".

Now, to the evil accelerator pump on my K124, which got me into this adventure in the first place. Most internal combustion piston driven engines are super happy when they are fed a fuel/air mixture ratio of 11:1 (11 parts air, 1 part fuel). What happens is, when you stomp on the throttle and open the butterfly quickly, you suddenly...for a few moments anyway... have way more air coming down the carb venturi than the suction can pull fuel in through the jets. Which really messes up your fuel air ratio to the point that there is no more combustion in the piston chambers, and the engine inadvertently stalls. (not good...not good at all! ) So, to combat this sudden "starving" of fuel at the moment of acceleration, mankind has invented this glorious gizmo called an "accelerator pump" ! The way this pump works is, via a mechanical linkage attached to the throttle ( or via vacuum on some systems) it squirts raw fuel from the float bowel directly into the venturi to balance out the mixture and keep things as close to the magic 11:1 fuel/air mixture as possible. Seems crude I know...but it actually works pretty darn well! I've already mentioned that the tolerances between the two plungers & bores on the carburetors I had to play with were rather sloppy. Not much I could do about that. So I then focused my attention on the free-floating steel check ball that is at the bottom of the pump bore tube or chamber. What it does is move up and free when the plunger is at rest to allow fuel from the float bowel to fill up the bore cavity, then it moves down and plugs the same hole when the plunger is activated which forces the fuel up through an internal passage on the side of the carb to be force-squirted into the venturi bore. Well, on both of my carburetor bodies, this little ball was corroded and the fuel passageways were completely plugged! Ah ha...I thought...here's the problem! So after cleaning out the best body and replacing the ball with a brand new shinny one, I put the carb back together (for about the tenth time...I'm getting pretty god at it I must say!). It was a lot better...but still not quire there. So all apart it came...AGAIN! After staring at each component for longer than I care to mention...I finally noticed that the accelerator pump is actually adjustable!!! (God bless the Russians...they must have a plan for everything!) There's a clip in a groove at the top of the pump plunger rod that holds the assembly onto the actuating bar. What I noticed is that the rod has multiple grooves in it so one can move the position of the plunger, while at rest, up or down to allow more or less fuel to fill the bore camber...thus giving you more or less fuel squirting into the carb bore at the moment of quick throttle opening. I set it one groove up (giving me more fuel in the chamber to be squirted) and behold...it works like it's supposed to!!!

and here is an example of what is meant with my two K124 opened up. The piston referred to is on the left in both cases. The shiny one has the clip set in a lower groove and will therefore have MORE fuel in the float to draw upon when accelerating. The darker one has the clip set higher up and will fill out less.

Raising up the plunger allows more fuel to fill the bore chamber which translates into more fuel being pumped (basically the same flow...just a longer duration) upon acceleration. Brilliant....simply brilliant! My guess is these K124s were engineered to be used on multiple engines of varying displacements. All one had to do is swap out the three circuit metering jets, adjust the high range plunger and accelerator pump settings accordingly, and presto...same carb with many different uses. Very cool.

[iannima]

Oh, and I found a K124 carburetor rebuild kit on eBay Germany from kesovagora (his eBay handle). It comes with some other parts for different models I'm assuming, but all the needed gaskets, jets, needle & seat, screws, etc. are spot on replacements.

I think we should bring this here, for ease of reading of members with a K124 . I have searched but this seller seems to have nothing for sale at the moment. There are other sets for sale. Is this what you saw more or less?

[iannima]

I have just been playing with my spare K124 and can confirm that there are THREE groves in total.