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Carb problem found..I think.

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64rocksprite

64rocksprite

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Well, after centering the jets..I found I still had to run the mixture adjustment nuts all the way down to get an idle. 2k rpm is hardly an idle!!
OK, too much air from somewhere..right? Took a can of gumout and starting spraying. As soon as I hit the throttle shaft on the rear carb, rpms increase. Did it 4x to make sure as the "idle" tends to walk up and down on its own.
So..I'm assuming that is where all the air is coming from forcing me to run the jets "rich".
Question now is, do I just ream for the oversized shafts..or go whole-hog and have the $350 rebuild done(which will include that I would guess)?
The carbs seem fine other than this leak at the shafts..if I had the reamer, I'd be tempted to do it myself! These are the original carbs w/ 74Kmi on them (with soft-parts replaced already).
Thoughts? Thanks all..
 
Same problem on my H1s. New shaft bushing solved it. Now idles way way low if you like 700RPM.

Sent the throtle bodys to Joe he put in new shafts and butterfly valves and fixed the leakage. Less than 100 bucks.

Only took me a month to sort it out to the point that I knew what the prob was.

I can now field strip a carb and rebuild in no time at all.
 
HS2s right? If they are HS2s , they don't have the same brass bushing in carb body as the other HS series carbs do, on the HS2s, the throttle shaft bore in the carb has no bushing, so the throttle shaft rides directly on the aluminum of the carb body, since the aluminum is harder than the brass of the shaft, the wear on HS2s normally comes from the shaft not the carb body. I'd say about 90% of time, you can just install new standard shafts in the HS2 to renew them. You'll probably see a fair amount of wear on the shaft where it contacts the carb body. Check this on your carb, with the buttefly removed, how does the standard shaft feel if you slide sideways just enough to get it off it's wear pattern. I have seen a handful of HS2 that actually needed bushings, but for the most part a new standard shaft will do the trick. Hope this helps.
 
Wow..thanks Hap. They are HS2's. I have not had the carbs completely apart, but was (wrongly) assuming that new shafts would do no good! I plan to pull them off the car today..easier to work on and I should replace those paper gaskets on the manifold spacers, etc.

I better jump on ordering some new shafts!

Appreciate all the input.

This is exactly why I sent Basil my "Dues" in place of the Healey org I joined last year!! This place is great.

Thanks - Devin
 
Devin,
Don't order the shafts yet. As Hap stated remove your butterfly and slide the shaft out enough (after thoroughly cleaning the parts) to test the shaft to body clearance. Check the amount of side play at this point. It will be a lot tighter and maybe better but you will need to know before spending monies on standard vs. oversize shafts. Do your homework and then decide the direction to go repairing the carb bodies or? I've repaired allot of SU carb bodies over the years for people and its easy once you have done a few dozen. For a number of years now I've had good success boring and installing a “type” of plastic bushing into HS’s and keeping the shafts standard size with zero problems.
Doug W.
 
Right Doug..I am going to pull them and disassemble on the bench. I have quite a bit of side play that I can see now (still on car) once the clamps are loosened. I haven't measured, but would guess it's on the order of 3/8" or so..(seems like alot)
Will let you all know what they look like (maybe post a pic)..
Thanks again.
Devin
 
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