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TR6 TR6 carb adjustment teacher needed

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ichthos

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TR6 carb adjustment teacher needed

My car is not running totally right yet, and I know this is because it involves me having to make adjustments on the carbs. Jeff at Paltech rebuilt these, and I have been leary to start making adjustments when I am not totally sure what I am doing. I have the Bentley manual, but I don't feel confident in what I am doing. Is there anyone near me that could show me how to adjust the carbs correctly? I know I could just take it into a shop, but I would really like to be confident in knowing how to do this myself. I am more than happy to pay for you time and gas to get here. I live in Rochester, about a half hour south of Olympia. I have not taken my TR6 for more than a five mile drive yet since working on my engine, but I would be willing to drive to your house if I could make it. I will be going on a trip to Olympia tomorrow for a longer test drive.
Kevin
 
Re: TR6 carb adjustment teacher needed

How's Tampa as a "goal" Kev?!? If ya get it here I'd be honoured to set 'em up fer nothin' more than LUNCH. :devilgrin:
 
Re: TR6 carb adjustment teacher needed

I would love to go to Tampa, appreciate the offer, but I don't think the TR would make it that far right now. I don't think I will get a taker for a teacher, but I thought I would try anyway. I will probably have to take it in somewhere and then examine their work after to see what they did.
Kevin
 
Re: TR6 carb adjustment teacher needed

Can you give me an idea of why you think they need adjusting ?
If Jeff set them up about the only thing they should need are a minor mixture adjustment and of course, idle speed.
Other than that, the sub assemblies such as the temperature compensators, the throttle bypass valves and the idle trim can and probably have been set on the bench and shouldn't need fooling with.
 
Re: TR6 carb adjustment teacher needed

poolboy said:
If Jeff set them up about the only thing they should need are a minor mixture adjustment and of course, idle speed.
Other than that, the sub assemblies such as the temperature compensators, the throttle bypass valves and the idle trim can and probably have been set on the bench and shouldn't need fooling with.
Click to expand...

I must agree.
 
Re: TR6 carb adjustment teacher needed

Over ruled. :devilgrin:

Always wanted to say that.
 
Re: TR6 carb adjustment teacher needed

feh.

There's SOMETHING else at work there.
 
Re: TR6 carb adjustment teacher needed

Ain't much we can do though without a little feed back. :crazy:
 
Re: TR6 carb adjustment teacher needed

It sounds like you are saying I only need to adjust the idle and fuel mixture, correct? I am not really sure how to do either. I know you say it is minor, but that is because you know what you are doing. Do you think you can talk me through this? I haven't touched the carbs at all up to this point. I don't know how to explain totally why I think the carbs need adjustment except for the fact that the engine is not running smoothly like it used to. Unfortunately I am going to start to have to use it for transportaion tomorrow. For example when I slowed down to pull into my driveway tonight, the idle dropped and the engine just died. I did start to try and adjust the idle. I let the car get up to temperature, and I put the synchro gauge on the front carb to get a reading. When I covered the second carb with the syncro gauge to compare, the idle went up on that carb. That never happened before,and pretty much stopped everything for me. Why would it do that?
 
Re: TR6 carb adjustment teacher needed

Not much to it, I've been at it for 5 years and finally got em purrfect.
You'll need a mixture adjusting tool.
Drive it for a while till it's at a good temperature and then without idling it too much shut the engine down.
If you're at home then wait for it to cool a while (so you don't burn yourself) and pull a spark plug fed from each carb, I use no. 2 and 7, the middle ones.
Check for a nice tan colour on the insulator nose, if it's black/sooty then it's too rich, if it's kinda white looking then it's too lean.
Remove the big nut (and don't mix em up)on the top of the carb. Use the mixture adjusting rool in the top of the carb to hold the air valve from turning while you adjust the needle height with the allen wrench part of the tool, anti-clockwise to lean, clockwise to enrich.
BTW, before you do this, make sure the points gap & timing is about right and that the choke retracts fully. Genreally try adjustments on the 1/4 turn variety.
Drive it, repeat pulling the plugs etc until you can home in on the right mixture on each carb.
Takes time/patience but you can do a lot of driving with a good excuse.
The idle goes up on the carb you covered because it's set too lean, when you covered it you accidentally improved the mixture setting
 
Re: TR6 carb adjustment teacher needed

There is a good article at https://www.buckeyetriumphs.org/technical/Carbs/CarbsIII/CarbsIII.htm

Your Unisyn is not properly adjusted, and is restricting airflow enough to alter the mixture. The carb where it went up, is running too lean.

Personally, I think Unisyns are more trouble than they are worth; you can do a perfectly adequate job just listening to the hiss through a length of heater hose. Hold the hose at the same position just in front of each carb piston; if they sound the same then the carbs are synchronized. It ain't rocket science, a small mismatch is not going to be detectable from behind the wheel.
 
Re: TR6 carb adjustment teacher needed

What do you mean the Unisyn is not properly adjusted? The article you posted (thank you) mentions I will need a mixture adjusting tool - is that correct?
 
Re: TR6 carb adjustment teacher needed

The Unisyn can be adjusted for the size of the air opening; yours is apparently set too small. What I found was that I had to tilt the tube with the ball, to make it more sensitive and get a good reading without upsetting the mixture.

Yes, you will need the adjusting tool (as Graham mentioned above). Part number CAT1 here (but any LBC vendor should have one)
 
Re: TR6 carb adjustment teacher needed

In a pinch you can use your finger to steady the piston by holding it pinned in the bore from the outside and use a long 1/8" Allen wrench to adjust. Clockwise raises the needle in the piston/jet, enriching the mix (leaning is obviously the opposite). An eighth of a turn will make a big difference so be aware.

But the first thing is to be sure they're drawing equally, as Randall advises.

That article is certainly comprehensive, BTW.
 
Re: TR6 carb adjustment teacher needed

Not all ZS carbs have adjustable needles. Somewhere in the past I thought that I read this was a 69 model. If that's right and the carbs are for a 69 then there are no needle adjustments.
Kevin do you have a small brass tag attached to at least 1 of the carbs ?
It would be under one of the 4 screws that hold the dome shaped cover on.
Need the #'s stamped on the tag.

On the surface it seems like you have the 2 carbs linked together with one throttle partially open and the other in a normal idle position.
It's easy to mess up tightening the tiny nuts that link the carbs together. If you happen to be pushing down while tightening one of the nuts, that practically guarantees that, unnoticed to you, the throttle is opening and when you are thru tightening it stays cracked open more than it should be.
Loosen one of the nuts so that the carbs are independent of each other, let the throttle return to normal, and be careful when you retighten, Keep pressure on the idle speed screw with a finger tip as you tighten.

Just make sure that both idle spped screws are just beginning to touch the stop when you do this. Then after the carbs are linked up equally, turn the idle speed screws 2 full turns, start the engine and make equal adjustments to get the correct idle speed.

I'd try that before you go monkeying around with the carbs, themselves, especially considering the recent Paltech work.
 
Re: TR6 carb adjustment teacher needed

That was one thing confusing me. I have a 69. I have never adjusted the needles, and I didn't think the needles are adjustable. There is no brass tag. I have two sets of carbs (a second set from another 69 engine only a few serial numbers away) and it has no tag either. Would a picture help? If so, do you need a picture of both carbs or a close up of one of them?
 
Re: TR6 carb adjustment teacher needed

Kevin, while you were posting this, I was adding to my last post. Have a look at the last couple of paragraphs. It's just my theory of where you might have messed up; it's easy to mess up when linking up the carbs, I caught myself doing it a few times.
 
Re: TR6 carb adjustment teacher needed

A picture wouldn't really help, there's no external difference between the 69 with non adjustable needles and say a 71 or 72 with adjustable needles.
Externally a 73 is unique and the 74-76 look pretty much the same as each other and I could identify those from a picture, but 69 thru 72 pretty much look the same, excepting vacuum nipple locations.
So no, lets just assume they are original 69 carbs...
Gotta go now and do some yard work. I'll check back before lunch and hope to hear of your progress..
 
Re: TR6 carb adjustment teacher needed

I am pretty sure they are both original carbs because both sets match. I have not touched the carbs in any way yet, including the linkage. What you said makes more sense to me. Maybe the linkage was not set right to begin with. Unfortunatly I have a long boring meeting I will be in all day, which I have to leave for shortly. I will try what you said when I get home. Will you be on line tonight? Hopefully I will not mess my car up too much by driving it this way.
 
Re: TR6 carb adjustment teacher needed

And Jeff didn't convert them to adjustable ???
 
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