why do mikuni screws suck?

[onesojourner]

It has probably been 4 years since I had to put a primer kit in and a just had a kick in the nuts reminder of how much the screws in the choke assembly suck. I think the heads of the screws may be made out of lead. a two minute project should not turn into a 15 minute project (or 30 minutes when the battery in the drill dies...) 2 carbs down one more to go.

 

[WFO Speedracer]

Heres a tip,take a file and file off the threads that are sticking out,takes about 60 seconds or so,then the screws will come right out with a screwdriver once you remove the threads that were staked.

 

[onesojourner]

I already drilled them out. its just a pain. why not use a screw some one can actually get back out?

 

[Big Kahuna]

I already drilled them out. its just a pain. why not use a screw some one can actually get back out?

do your really want that answer?

try this, remove the screws from the butterflys, install new screws, just tighten them up.......... now, in a few months or minutes, when your motor looses compression, please do not cry now that those screws have gone through your motor, messed up the pistons, cylinders, crank case and crank.

:rant::rant:

They are like that for a reason.

 

[Mouthfulloflake]

they are mushrooomed on the end so they will never vibrate loose and get ingested by your hungry engine.

you have to grind the backs off ( or use a file) to remove them by unscrewing them.

 

[Mark44]

u

I already drilled them out. its just a pain. why not use a screw some one can actually get back out?

Ummm think about it........:thinkerg:

Mark44

 

[WFO Speedracer]

I thought the answer to that question was obvious ,I guess I was wrong.

 

[onesojourner]

What is mean to say is the metal on the head of the screw seems to be extremely soft.

 

[#ZERO]

Replace them all with 316 stainless steel Allen screws from McMaster-Carr. :thinkerg:

 

[WFO Speedracer]

What is mean to say is the metal on the head of the screw seems to be extremely soft.

Yes the metal is soft so it can be staked effectively,you really can't stake any type of stainless screws they are too hard.

 

[onesojourner]

I am with you I guess that kind of makes since.

 

[Idok]

why bother to drill them out?

just take a pair of vice grips, put it on the butterfly shaft and with some banging, cursing and leverage they'll just rip right out

at least thats how I did it the first time lol...

 

[WFO Speedracer]

I am with you I guess that kind of makes since.

I will give you a little history lesson somewhere along about 1986 Kawasaki got a shipment of 44BN carbs that the choke screws were not staked on,those screws vibrated out and lunched many a motor,there was a bulletin to stake the screws using pliers with extensions on the handles for added leverage ,since that time all Mikuni watercraft carbs have come with the screws on the choke and throttle plates staked so they cannot back out.