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Newbie SU Carb Rebuild & Restoration Question

TEXAS_TR3A

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Howdy! I'm new to this great forum, and would greatly appreciate any guidance from you guys on the best place to send my SU carbs to be rebuilt & restored. Been lurking here for a while and am now digging into the TR3A one project at a time. The journey begins.....

I just received the carb overhaul kit, rebuild DVD, tools, Grose jets, etc. from Moss, with the intention of doing the rebuild myself, but then ran across the link below and boy do those SU's look nice! Wondering if I should just send them off and have it done professionally... I could probably make my way through the rebuild, having never done one, but don't have the setup to do the cleaning and restoration of the exterior to make them look anything like those. Has anyone used the outfit below, or Apple Hydraulics? Any other recommendations?

https://www.sucarbs.com/restoration.html

Thanks in advance for the help!
 
Welcome to the insanity, I mean the BCF!

Im not the one to ask that question,
but Im sure there are many people here with the expertise to help ya out.

again welcome!! :yesnod:
 
Hey, welcome Tex - you a part of the Houston Club?

Don't know that vendor, but I've seen that work on ebay for maybe the last 6 months or so. Looks pretty good.

Randy
 
Just my $.02 ... do them yourself. It's not that hard; and you'll get a much better sense of accomplishment that way, than paying someone else to do it.

And while I'm passing out free advice (worth every cent it costs); I'd also lose the Grose jets. IMO they cause more problems than they solve, at least on SU carbs. Not everything sold as an "improvement" really improves anything (except the vendor's profit).

Oh yeah, welcome to the asylum !
 
Hey Randy,

Nice looking TR4 in your avatar. I belonged to the TTR last year but unintentionally let my membership lapse. Will be getting it renewed in the coming weeks. Had the interest, but quickly realized I had no time to devote to the hobby given a hectic travel schedule and very young kids. Business travel has slowed so it should be manageable from here on out(crossed fingers) You a member?

Erik
 
Yep, if you get a chance try and get down to one of the Saturday breakfasts, not a bad way to get back in and there are always a few sidescreen guys there. I think this Saturday will be the Harris County Smokehouse in Tomball.

I'm also in the TR3a project club, though mine is more a collection of parts at the moment.

Randy
 
Thanks for the advice on doing them myself. I agree with the sense of accomplishment one gets from it. Any suggestions on what to use to clean them up, or should I take them somewhere locally to get them glass bead blasted? They are pretty well covered in dirt and grime, and while I'm not going for Concours, I would like them to look semi-new.

As far as the Grose jets go, I guess I shouldn't believe everything I read. Should have posted a question about them here first. What kind of issues have been experienced with them?
 
Erik - what other project are pending on the car? I ask because I'm a big believer in selective outsourcing. If the carbs are the only project, and yiu have the time, then dig in. If there are other things that will take more time that you also feel comfortable digging into then no shame in sending the carbs out.

As usual, your mileage may vary. Just another point of view. In any case welcome!
 
As to Grose jets, the complaint I've seen often was failing to seat properly and subsequently leak.
 
Thanks for the reply. Boy, don't know where to begin with the "other projects" list. The car has never been restored, and while in somewhat solid shape (Texas car since'63-no structural rust), I'm seeing a few superficial rust bubbles in the rockers and other areas here and there. The original paint is looking, well, original.(crazed, etc.) The undercarriage is well preserved with about 1/8" of oil buildup on everything from what I guess is a leaky rear main seal. The intention is to drive it through the winter and begin a teardown in preparation for a frame-off restoration beginning next Spring. It began dumping huge amounts of fuel from the bottom of each carb. about 2 months ago, and I thought I would get them out of the way so I could enjoy it for a few more months before taking the plunge.
 
Yikes..I'm trying to <span style="font-style: italic">fix</span> the leaking problem...not pay for another one. Guess the Grose jets are going back.
 
Might be as simple as seal at the bottom of the float.

Is this what your carbs look like?

TRI-013.gif
 
Welcome I have done the su rebuild before with bad results. the pair that I have with my project car that has been sitting in the trunk for about ten years and looked as bad as the ones on the link. I sent them to Chester and got them back and was amazed at how beautiful they looked. But the best part was that when I started the new engin for the first time Varooom. I am very pleased. About $350 Very cheap.
Dan
I
IMG_0013.jpg
 
I had Grose jets for 2 years on my ZS carbs. The very first time I ran the engine, one failed to shut off the gas. I pulled the carbs and rolled the ball a number of times hoping it was something from the machining causing the malfunction.
Whatever it was, that fixed it. Then about a month ago, both started leaking; so I replaced them with the original plunger type.
The most noticeable part of the SU's are the air valve covers.
Clean the grease and gunk off with carb cleaner and a tooth brush, then take after the polishing with metal polish and lots of buffing by hand or buffing wheel. If you use a buffer, stay away from machined mating surfaces.
The only part of the carb rebuild that I would farm out would be if the throttle shaft passages were worn out of round where even new throttle shafts left too much annular space.
 
In 1990, as I was finishing the restoration of my 1958 TR3A, I put in Grose jets and I can't say that I've ever had a problem in a little more than 100,000 miles of city and highway touring.
 
Could be different formulations in gasoline in different regions, but we have been seeing an effect, we believe, from ethanol on the old style needle/seat valves. The nylon(?) inserts get soft and the needle sticks causing the float bowls to overflow. The probems have been less with the grose jets.

Like I said though, could be differences in fuel formulations.
 
TEXAS_TR3A said:
Any suggestions on what to use to clean them up,
I'd start with cheap "carb cleaner" and a toothbrush, until you can see what the metal looks like. If you do have them media blasted, be sure to mask off the internals, particularly inside the domes, as they are a precision fit and very soft. You shouldn't even exchange the pistons between the domes, as they are matched. <div class="ubbcode-block"><div class="ubbcode-header">Quote:] What kind of issues have been experienced with them? [/QUOTE]
What I've seen is that they need more force to hold back the fuel pressure. On some engines, that is no problem, but if your fuel pressure happens to be on the high side or a float a little bit heavy, the float can sink at the worst possible time. I've 'fixed' several people's cars, by removing the Grose jets and putting back the ones they took out.
'Oxygenated' fuel may aggravate the problem too, as it's typically less dense (meaning it takes less force to push the float under).

The original brass-on-brass valves do wear somewhat over time, so it's good practice to check the float levels as part of a major tune-up. I also like to disassemble them and blow out any gunk ... if there is gunk then it's probably time to replace fuel lines. But I've got probably 150,000 miles on the ones in TS39781LO, and they were still working fine when it got wrecked.
 
Don Elliott said:
In 1990, as I was finishing the restoration of my 1958 TR3A, I put in Grose jets and I can't say that I've ever had a problem in a little more than 100,000 miles of city and highway touring.
OTOH, didn't I hear you complaining that your car didn't run well on US-spec fuel? It's lower density than what you get in CA ... those Grose jets might be part of the reason why
grin.gif
 
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