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GT6 Carb rebuild

jsfbond

Jedi Warrior
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In your opinion(s), can this be done by a carpenter? I have two new kits, the carbs have been run through a cleaning tank (by my bike mechanic). I have two really good books on the process, to guide me through it. or do I send them to Dave Clark @ Sports Car Services in Westminster, VT.?
 
You can rebuild it. Do one at a time...
Although for a little bigger carb than yours this will help: If you run into problems let us know.
https://www.buckeyetriumphs.org/technical/Carbs/CarbsI/CarbsI.htm

I should mention. These are Throttle Bypass Valves. You will have one similar. There is a diaphragm inside that will need replacement and I doubt if your kit included it. It's Moss part #365-745
 
I know for a fact that an electrician can do it. Oh and I'm a pretty good carpenter too. Give it a shot they are pretty simple and there is help available here if you get stuck.
 
Did the GT6 get emissions? I thought they only had the earlier "non-emission" version of the ZS carbs, which won't have bypass valves (and in general are much simpler than the later emissions carbs).

Should be no problem, although you may need some tools you don't have, or learn some new techniques as you go.
 
I think rebuilding carbs is one of the more pleasant jobs, as mentioned do one at a time, then you have a reference for putting it back together. Having the other as a reference is one good thing about doing the carbs, but the really nice thing is that, once you have them out, you can work on them on the workbench or even the kitchen table with appropriate protective covering. Much better than crawling under the car or leaning under the hood. A lawyer can do it, you can too, not to bad a job and nice to know it is all buttoned down and sealed well when you are done. Buy a can of carb cleaner or brake cleaner aerosol to clean everything off as you go.
 
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I think the correct answer is "HOW MUCH REBUILDING IS NEEDED????"

If rebuilding is just a matter of replacing all the bits then no problem. Now the real problems begin if the car body is worn out around the throttle shaft. If they are, this needs to be solved, and the best way it to ream, and but in new properly sized bushings. If they are only a little bit out of round, you can ream and get oversized shafts.

My solution to this problem was to get a big box of used carbs, take them all apart and find a carb body which was not worn out.

To check, put a new throttle shaft in to the throttle shaft holes. There should be ZERO play. (note I am not sure if the Carbs you have have replaceable seals that would make things easier. If you do have leaks around the shaft, you will never get it to idle properly and will be quite frustrated in the end.

Also, check the condition of the inside of the carb body where the throttle plate (the butterfly) rubs against the walls. If there is damage here you are also going to have problems. Basically when the throttle is fully closed, you should not see light around the butterfly.

If the carb body needs machining basically unless you have a machine shop or are willing to play around allot, you need some sort of professional help :playful:
 
I think the correct answer is "HOW MUCH REBUILDING IS NEEDED????"

you need some sort of professional help :playful:

Thanks for all the good advice, and my wife has been saying that for years.
 
As Randall said, the scope of rebuilding depends on which Strombergs your car has. The early GT6 (like mine) had the original ZS carb which has a jet that adjusts from below. That carb is very easy to work on and is "comfortable" to those who are used to working with HS series SU carbs. Those early ZS carbs are not complicated and are easily built and adjusted by a DIY person.

The later GT6 has the ZS2 carbs where the jet is fixed and the needle is adjusted from above. I have tinkered with those on our Spitfire but not fully rebuilt them. The ZS2 carbs do have more complicated components including thermostatic valves and air bypass connections. I have no idea how to adjust them but I would not be afraid to learn. As Poolboy said, do one at a time so you can refer back to the one that is assembled if you have any questions.

As part of the rebuilding, replacing the diaphragms is a given. Something that may appear OK but should be tested is whether the floats "float". Don't just shake them or assume they are OK. Put a quantity of gasoline in a container and drop the floats in. Both pontoons should float with the metal bracket connecting them hanging down into the fuel. For the ZS2 carbs there are new "stay-up" floats available from Burlen and Moss that resist ethanol. For the earlier ZS carbs (like on my car) there are not any float replacements available. Used donor carbs are important for those items.
 
Yep, big differences between the emissions carbs and non-emissions, but there is documentation on the web that helps. I cleaned and rebuilt mine and never touched a carb before.
One helpful thing is that, as someone else posted, you pretty much can't tune the carburetor so bad that it won't run. So if it doesn't work, it's something big.

Everything is pretty straightforward other than a few things, and these things are the same for emissions or non:

1. Make sure the post that the throttle plates pivot on doesn't have a big leak on it.

2. Make sure the plate that goes between the carburetor and intake matches the openings on the carburetor. I messed with mine for months off and on, could get it to run at idle but not drive, or I could get it to drive badly and overflow raw gas at idle... because the intake flange thing had the emissions port notch on it, and my non-emissions carb let just a fingernail of air past it.

3. Once you've got it all assembled, and your needle lined up, loosen the 4 screws on top, manually operate the needle in and out, and gently retorque - it should be super free. It's really easy because the needle is suspended just by the little rubber trampoline, to get it in a bind where it won't open and close smoothly. These carbs work by vacuum demand from the engine, so just opening the throttle plates won't make the needles go up, it allows more air by, more venturi, sucks the diaphragm up, etc. So the force at work doesn't like fighting sideways load on that needle.

4. Floats - you can test these in a cup of water in the sink if you don't want to mess with lots of raw gasoline. They're nothing elaborate, just hold them underwater and make sure they don't bubble.

If you have the CDSE (emissions ones) don't disassemble them more than you need to for cleaning. the yellow (by now, was originally white) bit has a bi-metal strip in it, that bypasses air at a given rate as you heat it. If you take the screw out of that, then you get to spend an hour or two heating water to a known temperature to make sure it opens at roughly the right point. If it's not broken, then it's close enough, you don't need to take it out or adjust it. :D Don't ask me how I know.
 
Richter! It's been a while since you have posted. When I last heard you and the Mrs. were starting a family. I hope all is well with that and it's good to see you post again.
 
Thanks for all the good advice, and my wife has been saying that for years.


:thumbsup:
Your sense of humor is the most valuable tool for the job!
 
Richter! It's been a while since you have posted. When I last heard you and the Mrs. were starting a family. I hope all is well with that and it's good to see you post again.

Hey there! I just popped in after hearing that my husband necroposted a rant in regards to the 2010 main cap thread. Curious about other activity, this thread shows up as his second most recent.

Our daughter will be 2 in August. Still haven't really touched the GT6 since, or the site for that matter. I finally received a British Heritage Certificate for the GT6 as a gift, which states that the engine with the main cap issue is indeed the one that came with the car. It seems as though my husband's planning on getting that one fixed for me.

My husband recently picked up a 1953 Packard Caribbean and a 1953 Packard Clipper (parts car for the Caribbean) so not real sure how we plan on juggling that restoration along with the triumph (although its pretty much done as I have driven it) With my daughter, its pretty difficult for me to do anything without her. But she really loves cars.
 
Congrats on the new acquisitions... including the daughter! I remember you saying you were expecting but I didn't realize so much time had gone by!

It is hard to make progress on any type of restoration work when you have little ones. Keep plugging a little on them every day and you'll get there in the end. Be sure to ask questions here when you are able to spend some time on the GT6.

EDIT: I just saw Richter's post on the other thread. I hope the caps I sent are useful. I don't have a lot of other early engine parts but do contact me if you need something else.
 
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Hey there! I just popped in after hearing that my husband necroposted a rant in regards to the 2010 main cap thread. Curious about other activity, this thread shows up as his second most recent.

Our daughter will be 2 in August. Still haven't really touched the GT6 since, or the site for that matter. I finally received a British Heritage Certificate for the GT6 as a gift, which states that the engine with the main cap issue is indeed the one that came with the car. It seems as though my husband's planning on getting that one fixed for me.

My husband recently picked up a 1953 Packard Caribbean and a 1953 Packard Clipper (parts car for the Caribbean) so not real sure how we plan on juggling that restoration along with the triumph (although its pretty much done as I have driven it) With my daughter, its pretty difficult for me to do anything without her. But she really loves cars.

Good to hear you two (now three!) gearheads are doing well Nikki! Although I don't know what the heck is up with those old posts showing up new again. Glad to hear you still have the GT6, along with the other additions - when I met you and your husband a few years ago I remember a Porsche being worked as well - has that been displaced by the Packards?
 
Nope! The Porsche is still there, all the big work is done and it runs very well, fighting a few small leaks around the transmission and getting in over my head on the interior work, but just this past Christmas received a new upholstery kit for the front seats and got those all taken care of. The door cards are another matter entirely. Sorry for leaving responses hanging, after the message board upgrade it looks like I wasn't automatically subscribing to threads I posted in anymore. I have that fixed again.

dklawson: We really appreciate you helping us out with the caps, unfortunately they were for the 2.0" mains, and the caps we needed were for a 2.3" main engine. It's appreciated though, and it's the thought that counts. We'll hang on to them for now in hopes that we can pay it forward if we hear of someone else with a need for them, or if you can use them, we're more than happy to ship them back.

We were up to 7 cars for a while, just sold one so finally down to 6, and hopefully will get back to 5, as soon as I cut apart this Clipper to get the floors out, and the quarter panels, door skins, pillars etc off for the Caribbean. It's such a big undertaking with so much to do, I get paralyzed just looking at the thing. Like my friend said though, it's like eating an elephant, you just have to start somewhere and expect it to take a while. :D
 
I just saw Richter's post on the other thread. I hope the caps I sent are useful. I don't have a lot of other early engine parts but do contact me if you need something else.

For whatever reason, we can't use them. Theyre too small I guess, and the crank is too big. Not sure if I can explain it right. But basically, there's just too much metal there to be rounded down to the desired depth. My husband located a source for main caps that will fit, but its from this horrible ebay seller, forcarent. We've purchased a few things from him in the past, not knowing he was the same guy, but he's incredibly rude, and you have a 50/50 chance of getting exactly what you paid for, and will have to open disputes. The only thing we did get from him that was ok, required driving quite a ways to be picked up at a greyhound bus stop, because despite claiming they would ship it to our home, it apparently cost too much for them. Anyway, pretty much, if I find a GT6 part on ebay, with a pic of it on a red tarp, I avoid. I would really rather my husband not have even considered purchasing caps from him, even if it meant that I would forever do without. He was extremely rude to me after escalating since I never got a refund after shipping things back. 4 years have gone by and we're at a different address. So odds are good that he doesn't remember us, but I remember him. In fact, when my husband discussed his conversation with the guy, as he was trying to sell us TR6 main caps, and my husband was merely asking if it would work with our engine, the guy sounded a bit rude, talking down to him. I immediately ask if it was "forcarrent" and sure enough, it was. I seriously think the only reason this guy is still in business is because he is the biggest ebay seller, some times only, who parts these out. That, and good buyers tend to wait till the very last minute to escalate, believing theyre getting a refund, which eats away at the feedback time. I never once gave this guy bad feedback due to the deadline.

Anyway, if you do come across anyone in the future needing the ones you sent me, just let me know. I would be happy to "pay it forward" and ship them onto the next individual.

when I met you and your husband a few years ago I remember a Porsche being worked as well - has that been displaced by the Packards?

No, we still have it. It still driveable, but is also pretty much on hold. If this Caribbean wasnt Packard's halo car, one of 750, worth $70-$100k fully restored, I would've done the evil wife thing and told him "take you money and your time, and finish your other car." In fact, the only reason you didn't see an RX7 in the driveway is because I made him sell it, as a condition of me lending him the money to buy the porsche, which, he paid back pretty much instantly. The deal with the packards were that they were local. I dont remember what we paid, few thousand, but a farm was being sold to developers because "OMG we need more houses!!!" and these vehicles needed to be gone ASAP. Since its local we will occasionally run into the seller and/or his friend. In fact, this just happened last Thursday.

The neighborhood we moved to has an HOA. The house you saw, clearly didn't. But we literally have 5 cars parked in our 3 car garage. Its quite a sight. Since both Packards pretty much HAVE TO stay in the garage, this makes things difficult. In fact, as soon as we brought the first one home, all three houses in front of us went on the market. Last weekend all three moved out. I'm a little suspicious.

I still have my mustang. ...because that's MINE!!! People have negative opinions about it when they find out I occasionally let my daughter ride in it. They seriously think its wreckless, and that I'm breaking some kind of law. Its very rare when she does ride in it, but seriously. You expect me to sell a car I've had since the 90's and buy a minivan/SUV? Do they require poor people to do that? CPS doesn't take their kids away. "OMG! You don't have AC!" I just have these crazy memories of riding up front with my parents. And when I was 5, DID NOT have a child seat! I cant believe my own mother, who, BTW, also thinks I'm a horrible person for doing it, would put me in such danger herself! I mean, stuff like that is actually illegal now. Not at all like what I do.
 
Sorry the caps I sent didn't work. Do feel free to forward them on to anyone you find who needs them. I bought a core engine only to find the block badly freeze damaged so I salvaged those caps for you before scrapping the block. Hopefully they will find a good home.

I am also sorry to hear about your experiences with the eBay seller. He has been around under a few different names over the years. I have only bought one or two items from him and never had any disputes. However, whenever a seller changes their name it raises red flags with me and like you I am cautious when I see the red (I thought they were orange...) tarps used as photo backdrops.

We took our kids around in our British cars regardless of what people thought. No... they aren't as safe as a modern car but we survived them when they were the new and "safe" cars of the period. I still remember my dad ADDING seat belts to a Ford wagon we had in the 1960s.

If the GT6 surfaces again as a priority project, do feel free to contact me either through the board or off list. I'll be happy to help where I can.
 
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