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Triumph TR6 - 73 TR6 ZS 175 CD-2

Ok, its been a bad couple of days. I removed the air cleaner with the intention of balancing the carbs. First thing I noticed was the 2 air values were at different heights. The air valve on the front carb was higher than the rear. Is this ok?? Then I proceeded to try and balance the carbs. I followed the steps on the tech page of Buckeye Triumphs. I was unable to get them balanced. I set the Unisyn on the front carb and then tried to get the rear to match the float level. No luck. So then I tried setting the unisyn float on the rear crab and getting the front one to match it. Still no luck. Has anyone else had this problem. Any ideas on what might be wrong or what I might be doing wrong? All help is greatly appreciated. Sure wish I knew a TR6 guru that lived near me. LOL

Hey, JW. The 2 air valves should be almost shut at idle. Several things could goose the front valve up higher, though.

First, with the engine & air filters off reach in and raise the valves. Is the resistance about the same? If not, check the oil level.

When you release the valves they should bottom out freely with a "click". If one doesn't, check that the damper rod is still straight and there isn't some crud between the piston and the rod preventing oil flow.

There is also a tiny air vent hole in the air valve cover near where the cap screws in. It's the one that oil flows out of if the dampers are too full and you lift the air valve all the way up. Get a pin or something and be sure that's clean.

If none of that works it's time pull the air valve covers off. Be sure the tops are oriented correctly (Buckeye has a picture). Check the diaphragms for holes, and make sure the spring is in the front carb (heh, heh). Clean the carbon and gunk off the air valves and carb bodies in a non-abrasive way (Mothers metal polish works good on the valve, - just get it all off. A rag with mineral spirits should work on the body), then reinstall. Don't forget the springs.

Screw the cover back on evenly. Check that the air valve freely falls to the bottom with a "click" - if not, loosen the screws a couple turns and retighten in another tightening pattern until the click is heard. Install the damper piston and be sure the still clicks. Remove piston, add oil, reinstall, and get the click. You should be OK to sync & tune then.

Brent B

Thanks Brent I will look at them tonight and see if everything is the way you say it should be.

OK Brent, both air valves are at the same height when the car is off. The resistance when raising the vavles seems the same. I also hear a click when I raise and then drop them. So I pulled the top cover off and looked at the diaphragms on both carbs. The front looked fine. However the rear one(the one near the fire wall) had holes in it. Ordered the diaphragms. However I am a little puzzled. You seem to indicate the front carb might have the problem since its air valve was higher. But I am confused now since I found the back diaphragm bad. Any thoughts? I will see what they look like when I get the new diaphragm tomorrow.

BTW thanks for your help

Hey, JW. As you point out I didn't really know what "higher" meant - turned out the other valve was "lower". With holes in the diaphragm it didn't get the lift it should have. Hey - I tried.

At least you found a problem, even if not directed straight to it. Also - it's best to replace both diaphragms at the same time - the other may be about to go bad. Clean all the carbon off, too, while the valves are out. Happy driving!

Brent B

Eureka, I replaced the diaphrams and adjusted the metering needles and balanced the carbs. Running like a champ now. Can't wait for the sun to come out and stay out. Gonna go cruising.

So now when we have Stromberg questions we just call JW.

Gawd I love having carb experts around when you need one.

He fixxed his, he can fix mine. <G>

Good job JW.

Jim Deatsch

This thread was discussed between 17/06/2004 and 20/06/2004

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