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GT6 GT6 Fueling Issues

I did retighten the screws after I loosened them, so they're not loose on top, still snug, just not torqued down as tight as I can comfortably get them, which has kinda been my habit. Also, I took care to tighten them crosswise, which I didn't do last time - maybe tightening too much and tightening one side all at once was holding it cocked? Now I can adjust the throttle by hand and watch both carbs open evenly and close when I let it off.

These were brand new filters from Victoria British, literally seen maybe 5 miles, but even then they ran badly. As I'm remembering, the time that I drove to the end of the street and back and everything felt awesome, I had forgotten to put the air cleaner back on. Like I had said before though, this doesn't seem like a normal paper element filter, these are hard and thick and yellow, and feel like construction paper over any paper element I've used in any other car.

And also, I never was able to adjust the mixture enough to make it run well with the filters - I'm talking drastic difference, as in, the car will idle well, and rev well, but if I put on the air cleaner with the engine running, the engine dies. Was Tegler the one that did research on the mix screw for those carbs that said that you really can't adjust the screws it to the point that it won't run?
 
How does it run with just the empty air box mounted on the carbs ?
 
poolboy said:
How does it run with just the empty air box mounted on the carbs ?

S*@#%*. I think I owe you a pitcher if we ever end up in the same place at the same time.

For future searchers or anyone else it may help. The GT6 airbox is two pieces. When you're assembling from a basketcase of parts it's easy to figure out that the intake hoses go out to the front.

The backplate against the carbs though, even though it's POSSIBLE to install it backwards, if you do that, it blocks off the opening for the air bypass and the fuel vent, which makes it, well, run like horrible crap if at all. Even if you run no filter and just use an empty airbox.

Right now it idles and revs at 3psi with the filters and the air box (correctly) installed. I'm about to take it for a ride to the end of the street and see how it goes.

Hours of my life, months of downtime, because the stupid airbox backplate is on backwards. :laugh: You're my hero, though.


edit:
Alright, it made it to the end of the block, but that was it. Still more than it's done in a long time. Maybe going back through the carbs with the carb book will help.
 
That's great. Let me try again. To the end of the block might be just long enough for a Vacuum to build in the fuel tank. If you pop open the gas cap, will it straighten out ?
 
But how did it feel as you drove to the end of the block? Was it better, marginally better, the same?
 
Still felt really down on torque compared to the one or two "This is how it should feel!" times, but better than it has been.

Still slipping the daylights out of the clutch to keep the engine from dying, and under load, adding more pedal makes the engine bog back down. Another alternative is that the fuel tank is one thing I didn't repair/replace, so maybe now that it's moving some fuel again, maybe it's clogged the lines again.

Contrasted to the one really good test ride we took, where my wife missed the shift into second (her car) came to basically a complete stop before letting the clutch out again, starting from a stop in second with no drama whatsoever.
 
Alright, so once before we had it running until the right turn at the end of the street it turned out the fuel line was clogged with debris from the old rusty fuel tank, so this time after nursing it back home, I picked up the POR15 tank sealer kit, and went to work. Now it's curing, and hopefully those problems are gone.

I got the carb book, and it really didn't do a lot for me, especially with the CD carbs, which are pretty simple anyway. Some extra reading and research on the Internet and I went back through the carbs to check the float levels, and it turns out that one side was a little high at maybe 20mm and the other was at 22mm. Either I started drinking beer before setting the floats that night, or it was the other carbs that I set the floats on (had a set of CDSEs that I took off to put the right ones on.) I set them to about 17mm now, better too much fuel than too little.

Also, when I was putting them back on, I noticed the spacers behind the carbs had the little port out (so instead of looking like an O, they look more like a Q, with a notch for some sort of emissions port, maybe?) Well, I had noticed before, but thought that the surfaces of the carb and intake would block it off. Noticed after reassembly that's not the case - there's about a 1 mm of that opening sucking air in between the intake and the carb. The spacer appeared to be made of masonite, so I went to see what I could find.

So I went down to the hardware store and picked up a piece of 5.6mm Lauan hardwood plywood for $6 and made a new set of spacers using the notched spacer as a template. I just traced the non-notched side, then flipped it over. Clamped them together and used a Dremel tool to make the perfect circle, and 80 grit sanding block and 150 grit palm sander to make them perfectly smooth and flat. Made a new gasket and a thin coat of black RTV and bolted everything together nice and snug.

I should be in a lot better shape than I was, but the sealed gastank has to cure for 96 hours before putting gas in it, so I wouldn't be able to put gas in until late Saturday. Problem is, we're moving, so it's going into storage early Saturday. I picked up 5 feet of fuel hose and I'm going to test it by sticking the end of that hose in my plastic gas can, at least as far as the trailer.
 
Well, idled nice, knocked it down to about 2.5 psi, backed out of the driveway, drove to the closed end of the block (I live near a cul-de-sac, and with only a few houses down there, it's much less embarrassing chugging along or pushing it home after my latest attempt fails). And it ran beautifully. Got to the end of the block the other way and ran great, so even though that was as far as I'd planned to go, I turned left and headed down the long road that runs through the neighborhood, up through second and into third gear. Made it about 2 streets down before it chugged and died.

Left the fuel pump run for a few seconds, keyed it up and it lit off, made it a few feet and died again. Like that pretty much all the way back home. By now I'm down to about 1 gallon in a 5 gallon plastic gas can, so I'm thinking that when the back of the car tilted or bounced at certain angles, it was sucking air. I poured the 5 gallon can down into a 1 gallon can so that it won't slosh as much and starve the pump and I should be great to get it up on the trailer tomorrow.

Thanks for the help and recommendations. I'm hoping we've finally got it - and after it sits in storage for a month and the gas tank gets a good long time to cure the sealant, I think I'll be in business. Might even make it out to the October show, but it's going to be a near thing, since we'll be pulling it out on Oct 15th, which doesn't leave much time for a shakedown.

edit: Oh, and the crazy whistling is gone, too - it must have been that 1mm opening from the port that stuck out between the carbs and the intake! It sounds GREAT.
 
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