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TR6 Triumph TR6 Carburetors
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Tinster
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poolboy said:
<span style="color: #660000">In that case, I'll be happy to post a photo of
my Pedro-ized carbs and intake manifold!!!
d</span>
poolboy
Yoda
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Do that, Dale. But I don't know if the true condition of your carbs would show up in a picture just of the outside.
And listen, the carb and emission set up of anything other than a 74 model would look darn simple.
Check out the illustrations in the "Emission Control" section of the Moss Catalog and compare the differences.
74s' got them all beat, hands down... What a mess!
And listen, the carb and emission set up of anything other than a 74 model would look darn simple.
Check out the illustrations in the "Emission Control" section of the Moss Catalog and compare the differences.
74s' got them all beat, hands down... What a mess!
The ZS carbs are really a simple device and probably cheap to mfg. The complication comes with the "constant depression" they require. The carbs we used on the old Fords and Chevys were less problems. You are right they do make up for the simlicity of the engine.
The SU carbs are in the same category of head scratchers, same type of constant depression devices especially trying to stop them from leaking.
Joe
The SU carbs are in the same category of head scratchers, same type of constant depression devices especially trying to stop them from leaking.
Joe
TRTUSH,
The SUs are somewhat similar to the SZs. The depression (vacuum) lifts the needle out from the jet allowing a proportional amount of fuel into the engine. I had a TR3B for a while but sold it.
I also have a '53 MG TD that has SUs. When I first fired up the engine after reassembly I couldn't get it to rev up, something about the carbs. I called that fellow Joe Curto who rebuilds these carbs, he said to remove the pistons on the dampers maybe that would help. I did and they work great without the pistons. Other than trying to stop gasoline leaks at the jet adjuster I'm OK with them.
File that little tid bit away, it might save your day.
One more thing is getting the needle centered in the jet hole. It's important that you should lift the piston and let it drop. You should hear a definite clunk when it hits bottom. If it doesn't then the needle is rubbing the side of the jet, not a good thing, you'll never get it to run right. I found it frustrating trying to get the alignment right. The jet in the body of the carb is made to have lateral movement so to position the jet for centering with the needle, it's trial and error ad nauseum. I finally solved the issue by making a dummy needle from a little length of brazing rod (about 1" long) inserted into the needle socket of the piston. The tip was pointed so when I installed the piston it moved the jet exactly into place. I then reinstalled the needle and had no more problem.
Other than what I just described you should have no other life threatening issues with your SUs.
Joe
The SUs are somewhat similar to the SZs. The depression (vacuum) lifts the needle out from the jet allowing a proportional amount of fuel into the engine. I had a TR3B for a while but sold it.
I also have a '53 MG TD that has SUs. When I first fired up the engine after reassembly I couldn't get it to rev up, something about the carbs. I called that fellow Joe Curto who rebuilds these carbs, he said to remove the pistons on the dampers maybe that would help. I did and they work great without the pistons. Other than trying to stop gasoline leaks at the jet adjuster I'm OK with them.
File that little tid bit away, it might save your day.
One more thing is getting the needle centered in the jet hole. It's important that you should lift the piston and let it drop. You should hear a definite clunk when it hits bottom. If it doesn't then the needle is rubbing the side of the jet, not a good thing, you'll never get it to run right. I found it frustrating trying to get the alignment right. The jet in the body of the carb is made to have lateral movement so to position the jet for centering with the needle, it's trial and error ad nauseum. I finally solved the issue by making a dummy needle from a little length of brazing rod (about 1" long) inserted into the needle socket of the piston. The tip was pointed so when I installed the piston it moved the jet exactly into place. I then reinstalled the needle and had no more problem.
Other than what I just described you should have no other life threatening issues with your SUs.
Joe
poolboy
Yoda
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I don't know. The principle of operation of the CD carbs is simple, but then you get to the CDSE, CD-2SE and the CDSEVX versions and you are dealing with things like the temperature compensator, the throttle bypass valve, the anti run on vent, any one of which can act up and throw things off course, it becomes a differnt animal.
SU carbs didn't seem to need all that ancillary stuff.
I know that much of the modifications were an attempt to comply with the Emission regulations of the 70's,but I can't help but wish they had found a way to do it with SU's.
Once you get all that stuff sorted out though, they are pretty comparable to the HS6 series SU.
I miss being able to adjust the mixture while the engine is running.
SU carbs didn't seem to need all that ancillary stuff.
I know that much of the modifications were an attempt to comply with the Emission regulations of the 70's,but I can't help but wish they had found a way to do it with SU's.
Once you get all that stuff sorted out though, they are pretty comparable to the HS6 series SU.
I miss being able to adjust the mixture while the engine is running.
TR3driver
Great Pumpkin - R.I.P
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Well, "they" did, but Triumph chose not to deal with SU. And there was basically all the same junk tacked onto them anyway ... for temperature compensation, there was a big thing hanging off the jet called a "wax stat" that functioned somewhat like a water thermostat.poolboy said:
https://www.minimania.com/web/Item/FZX3013/REB/InvDetail.cfm
Maybe Andy Mace or someone can chime in with the history details.
Hey PB, look at the jobs of adjusting the temperature compensators and the
by pass valves as intellectual challenges. Brain overdrivers. I'm just teasing you, they are frustrating. I have monkeyed around with them for the knowledge of what they do, and almost regretted it. I'm retired, I have lots of time to piddle around, it's a hobby.
Me too, I miss the simple listening to the engine tone change as you adjust the low speed jets. I had a '37 Ford Coupe and a '41 Ford Convertable back in my flaming youth, the late 1940s.
by pass valves as intellectual challenges. Brain overdrivers. I'm just teasing you, they are frustrating. I have monkeyed around with them for the knowledge of what they do, and almost regretted it. I'm retired, I have lots of time to piddle around, it's a hobby.
Me too, I miss the simple listening to the engine tone change as you adjust the low speed jets. I had a '37 Ford Coupe and a '41 Ford Convertable back in my flaming youth, the late 1940s.
poolboy
Yoda
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Retired here,too. Well I work on pools during the season, and hunt in the Winter. Do you have this as a reference?
https://www.buckeyetriumphs.org/technical/technical.htm
https://www.buckeyetriumphs.org/technical/technical.htm
