Author Topic: MC must be blocked up  (Read 743 times)

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Offline jeffg

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MC must be blocked up
« on: March 31, 2022, 01:40:17 PM »
I see the old post from 2013, MO MO and Lucky mention about the second MC hole getting blocked. Lucky say he had to drill one out and that looks like my deal also. Lucky say 0.010 was the size. I just checked all my small bits and my smallest bit is 0.025 can I over size the hole or do I need to get the 0.010 bit?

Online Don R

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Re: MC must be blocked up
« Reply #1 on: March 31, 2022, 01:53:39 PM »
 You may just need to bleed the air from the M/C. I had one recently that gave me fits until I loosened the banjo bolt at the top and bled it there.
No matter how many times you paint over a shadow, it's still there.
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Offline jeffg

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Re: MC must be blocked up
« Reply #2 on: March 31, 2022, 02:06:15 PM »
Hey Don I have the banjo bolt out, and if I put my finger over it and pump it does not build any pressure. I did get GOOD NEWS while I was looking for my small drill bits I found mt 10mm TBAR hahaha

Offline MauiK3

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Re: MC must be blocked up
« Reply #3 on: March 31, 2022, 02:14:19 PM »
Are your  piston and check valve in good shape?
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Offline Johnie

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Re: MC must be blocked up
« Reply #4 on: March 31, 2022, 02:28:52 PM »
That small hole is small for a reason you really do not want to make it larger. I used one strand of a wire wheel and kept at it going circles and it cleared.
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Offline jeffg

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Re: MC must be blocked up
« Reply #5 on: March 31, 2022, 02:53:43 PM »
I took a caliper to every small sewing needle and nothing is that small

Offline eldar

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Re: MC must be blocked up
« Reply #6 on: March 31, 2022, 03:50:23 PM »
Get a set of carb cleaning wires. There is a plenty small enough wire in there. They work excellent on jets, too.

Offline ekpent

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Re: MC must be blocked up
« Reply #7 on: March 31, 2022, 04:14:10 PM »
That small hole is small for a reason you really do not want to make it larger. I used one strand of a wire wheel and kept at it going circles and it cleared.
Like Johnie I have done the same exact thing even going so far as chucking that one single strand of stiff wire off a wire brush in my drill and slowly clearing the hole.
« Last Edit: March 31, 2022, 09:14:20 PM by ekpent »

Offline jeffg

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Offline beemerbum

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Re: MC must be blocked up
« Reply #9 on: March 31, 2022, 08:31:45 PM »
A guitar "E" string is perfect for cleaning that little hole. Steel string of course

Online Don R

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Re: MC must be blocked up
« Reply #10 on: April 01, 2022, 09:21:01 AM »
 I had a guitar with a saddle issue, that thing broke #8 E strings every week before I finally fixed it. I should have cut them into pieces and sold orifice cleaning strings. L0L.
No matter how many times you paint over a shadow, it's still there.
 CEO at the no kill motorcycle shop.
 You don't need a weatherman to know which way the wind blows.