Carb Questions

[55panFL]

This notched out washer was between the carb. & carb. support bracket. is this right?

20140301_173557.jpg

Also does any one have a couple pictures of a m-74 carb for a 55 FL that I can use as a reference for correct finishes?

[RUBONE]

Here is a picture of an NOS M53A-1. Finishes are the same.
Black Body, raw bowl, cad needles and body plugs.

[Cotten]

Dennis!

It appears to be an attempt at a shim.
(The original nut was thicker, although that should not call for a shim.)

'55s were a unique casting, as shown by the fourth one from the top:



In general, the small external hardware is expected to be cadmium,



although I come across many later issues with what appears to be flash-nickle chokecams. The shaft itself was bare. The chokeplate and poppet plate were 'cad', often with a bare center shaft, when brass.
The floatvalve was also bare, and the bowlnut copper crushwasher was of course, copper.

The lowspeed lift spring was blackened, and the spiral throttleshaft spring was "beryllium".
(Throttle lever assembly not shown was also 'cad'.)

If you can conserve any of your original finishes at all, it will be worth it.

....Cotten

[55panFL]

Most parts will clean up nice I believe. plan on just repainting carb body black again ( almost all paint is gone) . What have you found tho hold up for the black paint Cotten?

[55panFL]

My Throttle plate shaft has what seems as excessive slop at the top of the carb body. Is there a way to cure this or is it even a matter of concern? The bike has always ran great prior to tearing down to restore. Just trying to make sure everything is good to go before I go back together.

[1951 adam]

My Throttle plate shaft has what seems as excessive slop at the top of the carb body. Is there a way to cure this or is it even a matter of concern? The bike has always ran great prior to tearing down to restore. Just trying to make sure everything is good to go before I go back together.

I would go thru it and replace the bushings, how does plate fit in bore? Those are easy corrections and now is a good time to go thru it while it's down.
Adam

[Cotten]

Dennis!

Although it doesn't resist all pump fuels (or spray carb cleaners), I still rely upon VHT epoxy because it is self-priming, I don't have to charge an exhorbitant amount to have it gun-sprayed, and the customer can acquire it for touch-up down the road.

The borewear problem is a little more involved. As Adam points out, this is a result of excessive slop in the bushing and shaft, and replacement is always part of an overhaul, often long before anything else has worn.
When an excessive 'eyebrow' of wear prevents the disc from closing completely, particularly in the region of the idle bleeds themselves, I hone the bore of its wear, and custom-cut a disc to fit.



Since venturies nearly always need to be swaged and lathe-cut even at a stock bore, it is not an issue to take it a little farther.

....Cotten

[55panFL]

There is a small mark in the bore from the throttle plate but I cant even feel the edge of it when I run a pick over it so I would have to assume the bore is ok. But the shaft does have movement at the top so I assume that this should be addressed?

20140304_083444.jpg

[55panFL]

Here's a couple more pictures of the carb.

20140304_083622.jpg

20140304_083558.jpg

20140304_083612.jpg

[Cotten]

Dennis!

I will not be able to view your large pics clearly until I return home this evening, but from a thumbnail I see that your lowspeed knob is pre-M74B. It looks like the chokeshaft nut is 11/32", not 5/16" hex, and it is a serif'd "B" model such as the second and third examples in my previous photo.
None of these should affect performance, if everything is in order.

As Adam mentioned, replacing the shaft and bushings is a "given", as that is most critical for preventing the eyebrow of wear.

The fresh and shiny bare pivot screw in the bowl suggests it has been worked upon recently. Inspection requires cleaning of everything, particularly the venturi, so we look forward to what's inside.

....Cotten
PS: Since there's a MB of pics posted, I may not be able to access again until the thread has another page. My attempt to view them upon my old photoeditor declared one of them "corrupted".

[55panFL]

Is this the correct hole in the Bracket to use for the throttle cable?
This is how it was when I took it apart but I couldn't find any info on the two different holes.
Also there is a small spring above the cotter pin and flat washer Correct?
I got it in there but it was a pretty snug fit to get the cotter pin installed so I didn't bend the cotter pin all the way yet till I was sure It is correct.

[Cotten]

Dennis!

There are far too many large pics on this page for me to view.
(You can always email me direct at [email]liberty@npoint.net)

It has been common for folks to place one of the spiral throttleshaft friction springs upder the cable block, but with a sweet assembly it shouldn't be considered.

The inboard hole, closest to the throttle shaft, assures full throw of the disc.
I suspect others were a "governor"

I think your washer is over-sized as well, but it is hard for me to tell from a thumbnail,

....Cotten