No room for new throttle shaft bushing

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rich006

rich006

Learning as I go
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I have a junkyard Carter BBD that came with a Super Six setup I plan to install on my Dart. The throttle shaft has a bit of play, so I bought a kit to install a brass bushing. The problem is the hole in the throttle body is offset so there's not enough aluminum on one side (see picture). Can I build up that side by brazing aluminum onto it? Any tips on how to do it right? I've never brazed aluminum before but according to YouTube all you do is clean thoroughly, heat the piece really hot and then touch the brazing rod to it. I have a propane torch and the brazing rods are $5 at Amazon or Home Depot.

The shaft is 5/16" and the bushing has a 3/8" outer diameter. https://www.ebay.com/itm/5-16-Throt...e=STRK:MEBIDX:IT&_trksid=p2060353.m2749.l2649
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I don't see why not. I would find a junker throttle plate and try brazing it for practice though.
 
You could be making a mountain out of a mole hill. Isn't there plenty of bushing support beyond the little step on outside of casting? Only part of bushing that isn't supported is about the size of a finger nail clipping?
 
RedFish said:
You could be making a mountain out of a mole hill. Isn't there plenty of bushing support beyond the little step on outside of casting? Only part of bushing that isn't supported is about the size of a finger nail clipping?
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The thin side is on the right in this picture, but you can see the thin part is almost the full length of the bushing.
IMG_3442.JPG
 
Ace Hardware has thinwall brass tubing in various sizes. I researched, and found a reamer that was what I needed. I do this on Thermoquads that do not have a real thick base, at least not thick enough for those big bushings, in my opinion. Measure your throttle shaft diameter and post on here.
 
I don't know. Unless you have some kind of arbor/ reamer that can center/ align through all the holes going across, there is no way to line up such a bushing

EDIT "I see" said the blind man to the deaf person

I think I'd be tempted to install it as in this video, after cleaning CLEAN, and then if it looks "like a problem" JB weld it

 
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lemondana said:
Ace Hardware has thinwall brass tubing in various sizes. I researched, and found a reamer that was what I needed. I do this on Thermoquads that do not have a real thick base, at least not thick enough for those big bushings, in my opinion. Measure your throttle shaft diameter and post on here.
Click to expand...
Good to know. I have a thermoquad and may need to rebush down the line.
 
The Quadrajet's base is quite a bit thicker than the Thermoquad. That video or one similar was where I got the idea. So the Quadrajet can use the premade thicker bushings. That is why I found the thinwall tubing cut to length for the TQ. I had a hard time finding the correct reamer, But found one place that had what I needed. If anyone is interested I will post the tubing brand and the reamer brand and part number. They are out in the garage, so I will look tomorrow.
 
That muggy weld crap works great.. on aluminum cans and radiators. Guys at the show always use this stuff on the lightest stuff around. Try using them on anything with some mass, like a slanty intake or this part (well maybe). you need LOTS of heat to get the entire part hot enough to melt the stick with just a touch on it. Id try and use a oxy/acetylene rig if you have one or MAPP. Propane wont get it hoe enough IMHO. I tried to braze an aluminum crack in a slants choke stove and I rested the propane torch directly under that crack for probably 7-10 minutes and all the stuff did was ball up like solder. Even tried using acid flux on it and waiting for it to turn 'root beer brown" as directed but it never flowed. I gave up, drilled it and stitch pinned it. Also as stated if you drill out the hole to bushing OD, it has to be jigged to get it dead nuts centered in the original bore or else the butterflys wont go on right at the least. I heard a guy do this with an egg shaped throttle bore: coat the (new if old one is damaged) shaft with silicon spray lube and then install it with the butterflys all seated in their bores. Now pack the JB weld in the slightly opened up bore and let it set up. It should not adhere to the silicon spray so your shaft should break free easily once the JB is fully cured. Give it 48 hours. If that scares you, drill out the elongated bore oversize of the bushing and do the same thing: install the bushing on the shaft and set the JB around the centered bushing. It should seat and make the bushing the new bearing.
 
I'm back with the TQ bushing info. Don't mean to hijack your thread, but this thin tubing will probably work for your 2 bbl also. The reamer is from Kodiakcuttingtools.com. The part no. is 179661 and it was like 55.00 dollars. Ask for a catalog if you order one of these. Always nice to have another paper catalog. The thinwall brass tubing comes from Ace Hardware, and is K&S Precision Metal-part no 8136, 13/32X.014, you will have to cut to what you need. I put the tube over the smooth shank of a 3/8 bolt and cut with a tubing cutter, go slow as the cutter wants to crimp the tubing on the bolt. If anyone has a better way to cut this tubing let us know. I grind the peened ends of the throttle screws of with a Dremel tool. I get new screws from Fastenal, 4-40X1/4 Stainless Steel part no 72478, or regular steel-same size part no 32553. These screws don't have as large of a head as I would like to use, but they work-I haven't had one fail yet. Here again if anyone can find a screw with a larger head, let us know. You tighten the screws slowly while working the shaft to center the blade one at a time. I use red Loctite and peen the threaded end. This peening works best with two people, one to hold the base and one to do the peening. I use the same 3/8 bolt or another one mounted in a vise with the threads up. Position the head of the screw in that little cup and peen the end of the screw with a center punch.
I got a head of myself. I use a 9mm socket mounted on a 2-3 inch drill arbor, you will see why the extension later, I always ream the drivers side first because it is worn the most. Then install that bushing, then ream the pass side and install that bushing using red Loctite. I looked all over Lincoln for a 3/8X8 bolt to install the bushings, couldn't find one here, had to go to Beatrice- more of a smaller farming community, they had them. Again, back to the reaming, fill the 9mm socket with paper towel or whatever to just about the end, you will need as much of the cutting flutes as possible, go slow and in reverse as the video stated. When putting your shaft back in the base make sure you have everything in the right position. I'm sure there is something that I've forgotten, so post any questions. I have probably rebushed around 10 Thermoquads. Also if your shaft is worn really bad this will help but won't be as good as it could be. I always save all of the old TQ's for the throttle shafts. I've put Mopar shafts in the 9800 series GM Thermoquads.
 
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