Pilot Jet Removal

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Fatdog
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Pilot Jet Removal

Post by Fatdog »

Hello chaps.
I'm going to replace my pilot jets (or slow running jets) soon.
Has anyone got any tips as to the best way of doing them?
I know they can be a bugger to get out with the heads chewing up if your not careful.
I'm thinking a close fitting screwdriver, some WD40 and maybe a bit of heat on the nozzle block is the way to go but I'm open to any suggestions.
They are the originals, so I'm expecting them not to want to come out without a fight!
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Post by banner001 »

im not a religious man, but you missed prayer/divine intervention.

its brass which means it will break really really easily. What you mentioned is the best/only way, GT85 leave it to sink in, then a good screwdriver, plenty of downwards force and see if it turns, they are not supposed to be cranked in, just nipped, but they never are.

if it fails you will need a new jet holder...but its no longer an item you can buy, so if you mess it up you will need to buy a set of carbs and use them for parts...
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Fatdog
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Post by Fatdog »

Thanks Banner.
Pilot jets arrived today, so I might get chance this weekend to have a go.
My Wera screwdriver is a perfect fit in the new jets so I've got the right tool for the job. As you say plenty of downward force is the key and hope the brass holds out. :eek:
I'll let you know how I get on.
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Stig
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Post by Stig »

If the jets are tight give the driver a sharp twist with lots of downward force being applied. It'll usually crack the bond between jet n housing..... Constant force will usually lead to it shearing instead of it breaking the bond
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Post by Fatdog »

Ah yes, impact driver style.
Good tip that one Paul, thanks.
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Post by Stig »

I have a small version of an impact driver for such circumstances, think it's made by draper if my memory's accurate
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Post by skyerae »

My Dad, who was a mechanic for over 40 years always said that if you want to break a stubborn screw loose the best way it to put the screwdriver head in and give the top of the screwdriver handle a good hard whack with a hammer. For a really stubborn screw I give it a few good smacks and then use downward force to break it free. This works 99% of the time but use lots of penetrating oil, there is much better stuff than WD40, I use Plusgas, comes highly recommended.
If you can't do a job properly, don't do it at all !!!
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Post by nuggitt »

If all that fails Dave. I know somebody who will get it out for you. I had one stuck in and took it to Dynabike in Malton. If you have problems getting it out I'll give you his name, address and phone number. :nod:
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Post by Stig »

+1 for the plusgas. Brill stuff :nod:
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Post by oldskoolexup »

+2 on the Plusgas :)
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Post by Fatdog »

Thanks for the advice chaps.
My dad also taught me to help free a stuck bolt / screw by giving it a good whack first.
Not come across the Plusgas stuff though (it was always WD40 or 3 in 1 oil). Might have to have a look into getting some of that.
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Post by banner001 »

you can give it a good whack, but remember that its brass, and pliable brass at that, IMO hitting it would be a last resort.
Current bikes:
1989 UK FZR 1000 EXUP-R Streetfighter @48,000 miles
1993 ZXR 400 L3 UK-spec Track-bike @21,000 miles
1994 ZXR 400 L4 UK-spec Commuter @48,000 miles
1999 Malaguti Phantom F12 scooter with 70cc kit+mods @14,000 miles
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Post by Fatdog »

Good news, all jets came out a dream. :D
I sprayed the jet holders with WD40 and left it to soak overnight.
Using the right screwdriver, I did give it a few good taps (but not too much force) and then with a quick downward push and twist the jets were out.
Not sure if I have been lucky or what, but they did seem to offer little resistance.
New jets are in, fired her up and she ran crap!
Feels like it's only running on 3 cylinders, I'm hoping it's just fouled a plug.
Anyway I've pulled the carbs off again and stripped them down and blasted carb cleaner through all the passageways, jets etc and cleaned the spark plugs.
If that fails to cure it, it's going on ebay! :mad:
1993 YZF750R
EXUP - Knee Down
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