[czar97]

Not sure if anyone else has split bushing after bushing during the hammering / seating process.

What I noticed on bushing #1 was that while successful, the bolt supplied in the kit worked like a flair tool (see the picture).

Attempts #2 and #3 had similar results only much worse. These bushings split down the side at roughly 50% of their intended travel.

Looking at the radius that's formed where the head of the bolt meets the shank of the bolt, it looks JUST like a basic flare tool.

Final chance (with the last of the 4 bushings provided) I chose to use a bolt I had. See in the picture how it has a raised AND more importantly a FLAT area that pushes against the rim of the busing.

Everything worked great just had to file #1 flush with the Q-jet casting.

Just wanted to contribute something to the forum.

[Tom Vaught]

I made a Carb Bushing Tool for installing bushings in Holley base plates.
It would work on other carb baseplates too.

Holley carbs, many times, used teflon strips that went into grooves on the
throttle shaft. At the edge of the baseplate sometimes the hole is wallowed out.

I had some bushings made that just fit inside the base plate and bought a threaded rod that fit the slip bushings. These slip bushings center the threaded rod in the baseplate.

So to fit the press in bushings into the base plate you install the slip bushings and the rod, chamfer the press bushing slightly so it will center in the throttle base, then add a thick flat washer and a nut.

Now the press bushing is perfectly centered and you can use a simple wrench to slowly pull the throttle bushing in place. No hammering or centering the tool required like installing camshaft bearings. But I loaned out that tool and "it disappeared".
Sorry no pictures. (most bolts have a slight radius and that radius will split bushings unless you use a flat washer over the radius of the bolt shank.)

Tom V.

[77 TRASHCAN]

Hmmm, I have bought Cliff's bushing kit (comes with self aligning drill bit)and bushings. Have done 4 base plates...couldn't be much easier. Did have to hone the installed bushing with some scotch Brits, a fuzz. Hardest part was getting the throttle blades and the shafts removed...

[Greg Reid]

Yeah, I've installed a few and never had any splitting issues either. I used a nut on the bolt to actually contact the bushing edge.

[Cliff R]

Last year when I checked the books we had over 12,900 work orders since 2003. Not all of those were complete rebuilds, that would include all jobs we've done, bushing installs, heli-coils, bottom plugs, "tune-ups", etc, but every single carb that we do work on gets bushings. I use the exact same drill and driver that we sell, number of bushings split......zero!

I do run into a bushing once in a while that's a tad out of round and doesn't want to start easily, but even that is pretty rare. If/when this happens I very quickly chamfer the edge of the hole with my pocket knife and they go right in.

It's also pretty important to set the stop on the drill bit so it drills the hole just a little deeper than the length of the bushing so it ends up flush. If you don't drill the hole deep enough it's going to stop before flush, and any hits after that will certainly split it......Cliff

[czar97]

Again, I'd like to restate that everything worked out great with Cliff's bushing kit. As a first-timer I was certainly more than nervous when I wasted bushings on my second and third attempt. The drilling portion of the install worked like a dream. Great drill bit, bit collar stop and set screw. I looked at my dad and said Cliff has probably sold 10,000 of these kits with nothing but great reviews, so we must be doing something wrong. We kept looking at the first bushing and how it was 99% down with only minimal filing to do (success for sure) but how it was perfectly flared out on the end.

To some comments above; what I can say is that all 4 bushings started beautifully. All bushings advanced in the newly drilled / opened holes. All of the bushings began to fail at approximately 50% of their travel.

We even watched several youtube videos on bushing install to make sure we weren't driving them in with too many hits of the hammer or too few... or too hard. I planned to call Cliff the following day but after we found a bolt in the shop that had that super flat ring machined where the head met the shank we decided to go for it on the last remaining bushing. This ended with a perfectly installed bushing with even a very slight recess on end of bushing compared to carb casting.

Again, I can't recommend Cliff's kit enough. Everything is great and the movement of the primary shaft and butterflies is perfect. Zero slop or excess play.

["QUICK-SILVER"]

Being a first-timer didn't help. But, the kit did not work as it should.

Directions should have said "add washers" if the install bolt head doesn't bottom out against the bushing. And/or the bolt should never had the shoulder under the head to begin with.

Pics show the shoulder split the bushing before it made contact with the bolt head...

Clay

[Cliff R]

I'm not sure we're up to 10,000 yet but bushing kit sales have been pretty steady for at least 16 years. Just a rough guess at the number sold would be around 6000 or so, but at least 1/2 of those would have come from other vendors as we are a supplier for drill bits. We also make the drill bit in a 3/8" version which is a common size for many other types of carburetors and that makes up at least 1/3rd of the sales.

In all these years I can remember less than half a dozen issues, but never anyone splitting bushings when driving them in.

I should probably measure all the bits, but I just spot-check a half dozen or so from each batch instead. Coincidentally yesterday I was working on a 1977 Caddy baseplate and it had been dropped and missing a chunk/shaft bent. Instead of taking the time to remove the stop collar from my bit I grabbed one from the box and bored the hole 1" deep for a longer bushing. It drilled fine and bushing drove it with the same bolt/nut I've been using for decades.

I do recommend using a decent amount of Red Loctite, not really to hold it in place but it does act as a lubricant to help the bushing go in easier.......Cliff

[czar97]

I'm with you Cliff on the Loctite acting as a temp lubricant during the installation of the bushing.
After we cracked the second one we took some measurements just to see what we were missing. Everything checked out fine (slightly larger bushing O.D. than the bit diameter). See pictures attached for reference.

[Tom Vaught]

.002" PRESS is more than adequate. .006" Press even with aluminum is a bit much in my opinion. The bushing is trapped in the base. No way can it escape.

Personally when I have that large of a difference in the two parts I chuck the busing up into a drill press, using a machined true shaft, a smaller thread, two washers, and a nut. And then lightly use abrasive paper to remove the spread until I get about .002" difference.
I "dust" each bushing to fit properly in a measured location.
There is so much material in the bushing that removing .006" for example means nothing.

Tom V.

[azbirds]

.006 is a lot for a press fit. The manufacturer of the bushing may have had the machine go out of tolerance and several bushings went through before catching it? Either way, Tom has a good solution for it.