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Carb rebuild

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Kirk_Fisher

Kirk_Fisher

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My garage find TR4 is on the road and running pretty well. The car sat for six years before I rescued it, and the carbs really need to be rebuilt. I looked at Moss and Vic Brit and there are 2 options. One kit is like $36 and the other is $140 and neither come with the needles. Thoughts on what kit to buy?
 
I just re-did the carbs on my TR3, and opted for the $140 kit because it came with new throttle shafts, plates and bushings to redo the throttle shaft bores. It alos came with every other imaginable item that you could replace, except the needle as you mentioned. I had a lot of slop in the throttle shafts, so they had to be redone. This is a very common problem, so it might be best for you to disassemble the carb at the throttle shafts (take off the springy thing on the side) and see if they need shaft work done before you decide which kit you will need. There shouldn't be more then a couple thousands of play between the shaft and the bore. Fortunately for me, all of the wear was in the shafts, and I didn't have to bore out the carb bodies for the bushings.

Except for the throttle shafts, the rest of the carb re-do is a piece of cake.

Also, if you need to have the throttle shafts replaced and re-bored and don't have the capabilities to re-bore and/or drill the shafts for the pins that hold on the idle adjustment arms etc., then it might be best in the long run to just send the carbs out. There are several places often cited on this forum that do good work in this area.

As far as the needles are concerned, using the old ones should be just fine. That's what I did. Since there is such a wide array of needles, it wouldn't be economically feasible to supply the kits with all of the possibilities. Apparently, the SU needles don't seem to wear much like the ones in the Strombergs do.
 
Thanks. The needles were stuck in the bottom when I got it and I freed them up. I cleaned them with some sandpaper and they work ok, but they stick on occassion.

Dumb question. I noticed on Moss's site that new carbs for a TR4A are $650 and $1300 for the TR4 carbs. Any reason that you couldn't use the 4A carbs on a 4?
 
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Thanks. The needles were stuck in the bottom when I got it and I freed them up. I cleaned them with some sandpaper and they work ok, but they stick on occassion.



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The needles are probably sticking because the jets are not centralized. There is a procedure for doing this. When I get home later today, I'll dig out the instructions and post back.

Some very light sanding work on the needles would be OK just to get them clean, but don't do any more then that, as you will change the profile.
 
Joe Curto in NYC is the absolute best at rebuilding carbs. He did my TR6 carbs a few years ago. I couldn't be happier. Look him up at www.joecurto.com.
 
Rebuilding SU's is fairly easy compared to most carbs and professional rebuilds are reasonable too.
If you 'sanded' needles you probably changed their profile to an extent. Not always a bad thing, you'll find out when you run the car. The problem will be balance, are they reprofiled exactly the same? I'd invest in two new needles.
 
I bought the rebuild kit with the bushings for my 4A, and took the bushings into a local machine shope and had them fitted. It really made a huge difference. I'm glad I didn't buy the reaming tool. I can't imagine I could've used it properly. With the jets centralized, the mixture set right (not too lean), and no air sucking around the shafts, my engine is very smooth. Good luck with yours.
 
It runs pretty well for carbs that sat for six years, but it is on the rich side and not quite what it hsould be. I didn't "sand" them per se, just took a very very fine grit to get the crud off.

Have any of you used the Grose Jets needles that Vic Brit sells?
 
Kirk, I have always been a big fan of the Grose Jets, but I did fine out you need to rinse them in thinner before installing, they must put some kind of grease on them for shelve life and it gets sticky. Wayne
 
Thanks Wayne. That '49 TR is fantastic. Nice work.
 
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