® Sean MacGregor carb ebook errors
eBook dated 4-13-2013
This document 11-30-2020



You have to admire the work, the effort, that went into this ebook, as well as the fact that it is freely offered. I have done a lot of desktop publishing and it is more work than most people realize. So kudos for that. And, there are actually a number of things that stand out in a positive way techically about the booklet. For example, the procedure for throttle plate alignment, though I do it a very different way, and pilot screw drill-out, always a very delicate operation and one that requires bravery, I think. So, good on ya, Sean. Nonetheless, there are some glitches. And yes, the items below have been communicated to Sean.


pg 4

Phillips screwdrivers "small, medium, large"? No. Phillips screwdrivers are not sized small, medium and large. They are sized #1, #2, and #3.

pg 4

"$60 ultrasonic cleaner" A Harbor Freight unit won't do you much good. Carburetors take a minimum of 150 watts to clean.

pg 5

"Pine-Sol" As I've said many times, if Pine-Sol will get your carbs clean, so will gasoline or paint thinner.

pg 5

"carb kits" Do I really have to say anything about this? No one who respects carburetors thinks well of carb kits. Even some of the forums have finally caught up to this fact. No good.

pg 6

"ridiculous Phillips" Really? They look better and work better than Allen screws.

pg 9, 36

"removing sync screws" Don't. No need and no reason.

pg 10

"plastic seal ring" That ring is not for sealing. It is for cushioning. It also plays a role in tuning, even in starting the engine. Sealing takes place metal-to-metal.

pg 12

"PB Blaster on primary tube" Ahh, no. That stuff works no better on carburetors than it does on anything else.

pg 12

"can leave primary tube in place" Nope. You might as well not clean the carburetor.

pg 13

"reinstall limiter caps" Why? There is no good reason to have them and many good reasons to dispense with them.

pg 13

"not remove idle jet" Huh? What's the point of rebuilding? The most at-risk circuit in the carburetor you're going to ignore?

pg 14

"felt seals are unavailable" Not so. They have been available for probably twenty years now.

pg 17

"secondary slow jet" There is no such animal as a "secondary slow jet".

pg 21

"shake test floats" It is extremely rare for sealed hollow plastic floats to take on fuel, and the earlier solid plastic ones cannot. Shaking is not the best test in any case. Water testing is.

pg 22

"keep secondary main jet on its tube" No. The seccondary main jet must be scoped out all by itself, and "sized". And it can't be sufficiently cleaned attached to another part.

pg 23

"burnishing float valve seats" No! Never! This is very bad practice!

pg 24

[ignores float adjustment] This ignores 1979 models.

pg 37

"wire under throttle plates" No! Never! Good way to completely damage a carb set.

For more powersports maintenance fallacies, see this article.

More book/video critiques:
Julian Ryder
Mark Paris
Randakk
Common-Motor CB550 Sync
Common-Motor CB450 engine


Last updated August 2023
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