This is becoming a mammoth job. The deeper in you get the more you
realise how difficult this is all going to be to put back together
again. Ever since I can remember, things have been easier to take
apart.
Sometimes we have little victories and sometimes we have little disasters. Today I had both and they weren't little either. Carbs 1 and 4 had been straightforward, now I was onto carb no. 3. This has been my toughest challenge so far in the whole project. Pretty soon I will be an expert at drilling / dremelling out nasty screws and jets.
Sometimes we have little victories and sometimes we have little disasters. Today I had both and they weren't little either. Carbs 1 and 4 had been straightforward, now I was onto carb no. 3. This has been my toughest challenge so far in the whole project. Pretty soon I will be an expert at drilling / dremelling out nasty screws and jets.
I had 2 things go wrong today; firstly the air pilot jet would not come out of this carb so it had to be drilled. Secondly, one of the screws on the bracket that is attached to this carb would not come out either. The bracket is part of the mechanism that attaches the throttle cable to the carbs. It provides the resistance so that when the throttle cable is pulled the butterflies will open.
This is my no. 3 carb and the pesky screw location (click to enlarge):
There is a top one and this is the bottom one. Top one came out with concoction and brute force on the screwdriver
The bottom one wouldn't. Now I have ordered a set of JIS screwdrivers from the USA but I also found one I already had that seemed to be a good fit. So rather than wait (patience will get you over most problems I now learn!) for the correct tool to arrive to do the job, I thought I was smarter than that, I could do it with mine. A mangled head was the result.
No problem. I have dremelled new slots in pesky screws before. I will do it again.
Nice slot I think.
Except I went too far. Now the slot has eaten into the carb body. This in itself is not the end of the world but what it means to the screw head is a disaster. The top (thick) part of the screw is no longer able to be used as part of the unscrewing process. All the force of the screwdriver will now be on the weaker part of the screw. Guess what happens then? Get a nice fat and wide screwdriver, apply a bit of force and:
the head breaks in half. Another disaster. So get the Dremel out again (I use it so oftern now it lives on the workbench) and cut the other half off. That way the bracket will come off and there will be part of the screw proud of the carb body. Then you Dremel another slot. This time remembering not to go too deep.
Get a good fitting screwdriver and give it another go.
But it starts splitting apart already.
Then half of it splits off completely. We are left with the mole grip option.
I've read of people using this option but for the life of me I cannot see how it would ever work. If it wasn't going to come out with a screwdriver I was never going to get enough grip on it with a mole grip to make any impression. Another fail. This booger is only going to come out with a drill. So, Dremel the top flat, punch a starter hole and get drilling. So glad I got a Dremel for Christmas.
Starting to drill. I began with a very small drill using the punch hole as a guide to keep the drilling central. All this is done with a hand drill. It would be a lot easier if a had a bench drill. But I am about trying to make do with what I have.
It's all coming out now.
And the thing to do is not to lean on the drill too heavily ........
otherwise you might just drill straight through the carb! Although this looked at first to me like the end of the world as we know it, I do believe that it is not quite so cataclysmic. No. 2 carb has a similar hole in it that provides the vacuum to the petcock. What that tells me is that the venturi will not be compromised by an aperture at this location. This is the aperture used by the petcock vacuum hose in no. 2 carb.
Then I had to get the remaining bits of the screw out of the hole. That meant a bigger drill bit. As soon as I put this in and turned it a few times, it all came out
apart from a little bit that needed to be hoiked out with the bent paper clip trick
You may be wondering just why I am being so obviously over ambitious with what I am doing. I am determined to take this thing back to the very nuts and bolts from whence it came. I want to learn all I need to know on the way and I have a secret weapon .......
a completely new (well used but new to me) set of carbs that has just been flown in from California (I live in the UK). Picked up for a very reasonable sum and brought over to the UK for $25. This is my insurance policy. If anything goes wrong I have a complete set for spares. I can use it for spares or refurbish them and use them instead. It also means I have a control set that will show me how to put my original set back together. Even though I have had some trials taking these carbs apart, I do believe that putting them back together is going to be even more testing. So having a spare set is going to be a real blessing down the road.
Oh and I had to get out a stripped air pilot jet.
Start with a small drill and then get a bigger one.
I used the "tape on the drill bit" trick to try and prevent over drilling.
Then it all came out nicely.
However, after measuring the depth of the hole, the depth of thread and testing it with another pilot jet, I can report that I drilled too far and took out most of the threads. I can now only turn the pilot jet 1 and a half turns before it hits bottom and this bottom is about half a mm deeper than the bottom on an unmolested carb. I am going to have to get this one drilled and have a helicoil or insert put in. If this is even possible.
Otherwise my no. 3 carb body is toast. Wow am I glad I paid out for insurance.
Oh and I had to get out a stripped air pilot jet.
