Help needed on Carbs related prob or not?

[Meilakj]

Hi All,

I am new to the forum and allways been reading your topics and now its my turn !, I have my Z1B which I have got around 4 months ago , but only started to use it now , but I have some issues which need dealing with and not sure were to go next !!

BIke has always run abit rough on idling and when trying to drive on low revs it does not like it at all , so I allways have to keep it high revs from 2000 up wards so driving slowly on a high gear is a not easy.

I have found that plugs 1,2,3 are totally black and number 4 really clean. Obviously I know that they are for sure not good and I am trying to see what to do . I try to go for a run but it gets worse and sometimes even plug will not function any more and I replace . Obviously when I install new plugs its much better but then I am back to the situation . ONly improvement I saw was when I used B7ES plugs insted of B8ES , but it still ended up the same .

Up till now I have dismantled carbs 4 times for sure , had them vapor cleaned from outside . I have checked every passage possible and blowing air to make sure all is ok . I have not done carbs in an Ultrasonic bath . I have also sent plungers for seal replacement but this is also has made no improvement . I have also tuned carbs as per Kawasaki workshop manual and also calibrated with Gauges . What I noticed when I tried to set air jets the number one has no effect if I close it all or not , Also I tried increasing air and still no difference.

From Here not sure on what next is to check , I did a compression test but it was on a cold engine and they were all over 80 , which I believe is with in limits?

Any help on next step would be greatly appreciated .Unfortunately not sure how to proceed . I was thinking maybe find a used set of carbs but I am not sure that problem is really carbs ?

Thanks

John

[z1bman]

airways are blocked in the carb body underneath the carb slides 85psi compression is the bare minimum & i wood be looking at the valves & bores for excessive wear

[chrisu]

service limit is 100psi if i remember correctly with throttle wide open.

[keith mayall]

most of the time its carbs,do a compression test when its hot throttle open,if its under 100 you need rings valves regrinding ect,send your carbs to davez1 on here up in sunderland ,they come back mint and ready to go.

[zed1015]

Number 4 is either very lean or not getting fuel at all and the other three are extremely rich if it isn't oil fouling.
Make sure the air passages from the carb mouth to the needle jet tubes are clear and that the small holes in the needle jet tube are not blocked.
You should also check that the air passages to the pilot jets are clear too.

If the plug fouling isn't fuel but oil ( difficult to tell from the pic ) then you possibly need at least all new guide seals but coupled with the low compression also work to the cylinders and rings.

You should check that the valve clearances are not tight first to eliminate those as the cause of the low comp.

[Meilakj]

Hi All ,
Thanks for your input guys ,

Started some more checking . I am trying to avoid opening top end for now . Which also made me think , if it was oil burning would it also be smoking from exhaust ? Which I did not see this happening during the time I was testing it.

I opened top cover and Valve clearances are all within limits except for 2 which are slightly above 0.10 mm range but not more than 0.12 which I think it should not be the cause of soothing plugs? or the other way very lean (number 4)

I have dismantled carbs once again and after thoroughly, looking and checking, I have found that carb number 1 (Choke lever side ) has a small hole which explains why when I closed the air screw all the way it made no effect on bike , since air would go trough this tiny hole . Forgot to take picture , This also got me thinking , if there is this type of damage on one carb , could there be other damage internally is not visible ? ( lets hope not !)

Next step I will do tomorrow is put carbs in Ultrasonic bath to see if it helps , altough this would still be leaving me needing a replacement of carb number 1 or I might even try blocking since its just a little hole abit more than a pinhole ! I have nothing to loose I think .

Not sure how this goes but will take a chance .

THanks

John

[zed1015]

The valve clearances want to be 0.10mm MINIMUM and 0.15mm max for a stock engine.
The 0.05mm to 0.10mm figures in some manuals is wrong and was changed early in the production run due to issues with valve seat burning.
Excessive black smoke indicates fuel burning and blue smoke indicates oil.
Your bike should be producing one of them but probably needs someone following you while the bike is ridden under load for it to be seen.
A pic of the pinhole in the carb would be of help.

[Strebe]

Your sooty plugs could also be a symptom of a low voltage at the coils. Check out : https://www.wgcarbs.com/index.php/using ... s/89-coils
for the “wired George” solution - which is basically adding a direct battery feed to the coils, switched via a relay.
Ultrasonically cleaning the carbs is definitely a good idea, but if that doesn’t eliminate the sooty plugs problem, I’d recommend the wired George mod before you think about a replacement set of carbs. Good luck!

[Meilakj]

Thanks on info about valves , did not know this , I was going trough manual , will check again the spacing aswell . Its all learning as I go on these bikes .

I have managed to take photos of the carb with pinhole , it was abit tricky to be able to get it showing , but managed by showing the light trough the hole and taking a photo. Also from outside you can see it .

I have managed to find a new one , but I was thinking that I might be able to close it up with some chemical , espcialy since it is very small , Also I do not see nothing to loose in trying ?

I also did all carbs in Ultrasonic bath for ever 90 minutes . at 50 - 55 degrees , then gave them a good blowing with 8 bar compressor , all pasages seem open and ok . Also jets seem all ok and no blockages . Plan is to assemble again and give it another try .

In the mean time I have ordered gasket kits to go to the next step if neccessary and open up the top end . Altough its first time working on a Kawasaki I am sure I should manage it.!!

Any other suggestions would be appreciated !

John

[Meilakj]

Your sooty plugs could also be a symptom of a low voltage at the coils. Check out : https://www.wgcarbs.com/index.php/using ... s/89-coils
for the “wired George” solution - which is basically adding a direct battery feed to the coils, switched via a relay.
Ultrasonically cleaning the carbs is definitely a good idea, but if that doesn’t eliminate the sooty plugs problem, I’d recommend the wired George mod before you think about a replacement set of carbs. Good luck!

Thanks for this extra info , I will defenietly will check this aswell . I also can manage to connect a relay with no issues as I am quite familiar on electrics,


Thanks

John

[zed1015]

You were lucky to spot that tiny hole.
Looks to be a casting flaw/air pocket that may have been there and causing problems from day one unless the recent blast cleaning uncovered it.
Some chemical metal on the outside of the casting will cure that or if you are feeling brave some aluminium solder.

[compo z1r]

You were lucky to spot that tiny hole.
Looks to be a casting flaw/air pocket that may have been there and causing problems from day one unless the recent blast cleaning uncovered it.
Some chemical metal on the outside of the casting will cure that or if you are feeling brave some aluminium solder.

Silver solder u can use not as high temp required sticks to most metals just had it done to the water jacket on a willys jeep under pressure from engine water temp sealed well !!

[Meilakj]

OK so did some more work today . I re assembled carbs , I managed to block the pinhole that I found. Cleaned up plugs and fired up ,

Bike initially starts as usual working ok , then a re checked carbs with carbtune . all ok also this time I removed air filter and air jets I set them 2 turns out on 1, 2, 3 and one turn on 4 .

Went for a ride and bike once again was not so good .

I then re cheked plugs and this time 1 and 2 are still soothed but 3 showed a slight progress but still abit rich , and number 4 not so lean as before .

Also this time I was able to do a compression test , since engine was warm . All are around 105/110 psi except for number 2 which was 100 psi . What do you think about compression test results ?

I also checked voltage at coils and this is showing 11.33 V , at the coil connector , at the battrey its 12.42 V so along the way its losing 1 volt , Would this make that much of an effect on coils ? Also bike is with Dyna S ignition .

At this stage I am not sure which way is next , but I have a freind which had offered to try the carbs of his bike , which I was abit not sure at that time , but I think I will ask if he is still willing to help out .

Any other input would be appreciated ?

Thanks

John

[Meilakj]

So I have an update ,

Managed to fit on my freinds carbs on my bike , The bike ran perfectly !! yes perfectly !! We went for a 30 mile trip and it ran as smooth as needed . Keeping low revs on high gears with out engine stalling !! Only thing that is needed is to to have are jets set as it was abit lean , but I did not want to touch settings since the carbs were set to his engine .

All 4 plugs had the same burn which was abit on the lean side .

Next step is to retry once again to see for any faults in my carbs not sure what I need to check but I will be taking them apart once again . At least I can say that coils and timing is ok and also no need to take of head !

Also might be interested in buying a set of carbs for Z1B if you have any available please let me know.

Thanks

[Meilakj]

Hi All ,

Just an update on carb issue .

finally managed to solve it out , I ordered another set of carb kits , this time I got the Keyster carb Kit which also has the needle jet included in the KIt and not like the Tourmax carb kit .

Re installed carbs and bike now runs pretty well , and all plugs have a nice colour .

I hope this tread helps other guys if they have any issues similar to mine .

Thanks