GT6 Triumph GT6, basic work estimates

[LarryK]

If they did not use alcohol resistant hoses, they can start deteriorating immediately. Gasoline and oil both float on water is why you cannot test in water.

 

[UmmYeahOk]

I am trying to help you, not to upset you concerning the shop and what they have and haven't done. Please don't shoot the messenger.

If I sounded on the defense, I apologize. It was not my intention. I simply wanted to tell you what I have done far, and question if these theories still applied.

I decided to take apart the working carb, because if one float valve is sticky then it’s only a matter of time when the other one will be too. To my surprise, this float valve looked completely different! It has a cover AND a washer! Could this be the reason the other keeps flooding? And if so, could it still function properly for 50 miles before developing this issue, or would it be an instant thing? Where can I source a replacement?

~~UPDATE~~

I checked everywhere looking for that washer in the off chance it fell during removal, but I couldn’t find it. Luckily I had another pair of carbs, so I took a washer off one to use with my good float valve. I then found the correct washer hidden inside a tiny pocket within the frame. I had previously checked every nook and cranny with a flash light, but I guess I didn’t see it before because it was a red piece of plastic (or something that can handle gas I’m assuming). I installed it, and now no leaks.

I will give the shop the benefit of the doubt and say the washer error was on my part, but it still doesn’t change the fact that these clogged up after 50 miles. Yes, it’s possible that they did everything right, and something simply got missed within the lines, but it’s just a little irritating that EVERYTHING we paid them to do had to be redone.

~~UPDATE TO THE UPDATE~~

As I was writing the first update, while the car was running, it started flooding again.

 

[dklawson]

I hate to ask you to spend money on fixing this but... contact Joe Curto and buy two of his float valves. His are "correct" for our cars. Assuming you still have the original carbs installed, these are 150 CD carbs not the later 150 CD2 models.
https://joecurto.com/

I have not thought to ask you about this previously. Does your car still use the original mechanical fuel pump mounted on the side of the engine block or has it been converted to an electric fuel pump?

 

[UmmYeahOk]

We had an electric fuel pump on it before sending it to the shop. The original mechanical pump was installed for looks, but bypassed. In addition to rebuilding the original generator I had and replacing the aftermarket alternator with it, he replaced the electric fuel pump by making the mechanical one work again.

 

[LarryK]

I had problems with the grosse valves on my 73 XJ6 and my 73 GT6. Mine leaked while sitting in a parking lot. I had to call the wife and tell her where the old ones were and changed them out to drive home. Never used grosse again.

 

[dklawson]

I don't like Grose Jets either but the pictures posted earlier (in post #42) were two different versions of the regular Stromberg float valves.

If I understand your last post, the car is currently operating with the OEM mechanical pump. Is that correct? If instead it is running on the electrical pump it is imperative that you either install the proper low pressure pump OR fit a pressure regulator between the pump and carbs. Strombergs and SUs don't like more than 3 PSI fuel pressure.

 

[trrdster2000]

We have had major problems with the new pump (mechanical) having a spring under the diaphragm that was larger than the original giving out 5 or more PSI.
Not a lot of trouble to replace or check the spring or pressure in the line with a gauge. The vacuum gauge will most likely have a pressure gauge reading under the vacuum numbers. A good gauge to have in any case.
One other little error that is made, the gasket from the air filter can be turned the wrong way and cover a vent hole, most new ones will go either way but some of the old ones are still around.

 

[UmmYeahOk]

I don't like Grose Jets either but the pictures posted earlier (in post #42) were two different versions of the regular Stromberg float valves.

good eye. I was going to use a washer off a third one that I had, and noticed that it’s thickness differed from the other. So my spare float valves don’t match either of these two as well.

If I understand your last post, the car is currently operating with the OEM mechanical pump. Is that correct? If instead it is running on the electrical pump it is imperative that you either install the proper low pressure pump OR fit a pressure regulator between the pump and carbs. Strombergs and SUs don't like more than 3 PSI fuel pressure.

its currently using a mechanical. My husband (Richter12x2) reminded me that when he installed the electric fuel pump he had to dial down the pressure as anything over 4 PSI would cause flooding as well.

while fiddling with the carburetor initially, I discovered also, a major vacuum leak going into the bad carb itself. Not sure how that effects it, but I bought a replacement earlier this evening.

One other little error that is made, the gasket from the air filter can be turned the wrong way and cover a vent hole, most new ones will go either way but some of the old ones are still around.

the air box has been removed ever since the flooding started and has not been reinstalled since.

 

[UmmYeahOk]

UPDATE:

I finally took everyones advice and tested the floats in actual gasoline. They do not float like they did in the water. I honestly didn’t even need to test in gasoline, as when I removed it, I shook it, and could hear the liquid inside. These were “rebuilt” by the service shop, which is why they had this odd white paint. The floats in my spare carbs are incompatible, so I’m wondering where to get a replacement or if I can repair these myself. After removing the gas inside, what would be needed to glue and seal it without having the gas eat at it?

 

[TR4nut]

Don't waste your time on trying to fix. Joecurto.com as Doug suggested. Or Spitbits. Nitrophyl floats, I think B1947ONT is the part number but best to call to confirm for your car.

edit: well it may be more complicated as that part is listed for GT6 and TR6 as well so may not be correct. But still worth a call to see if geometry is similar or same. the early float appears to be part number 515721 and Rimmers shows it no longer available. Call Mr. Curto is my recommendation as well.

 

[trrdster2000]

How crude to try and fix the known problem with a bunch of goop.
They are a rare float, being a single tab for the needle seat, but the double one can be used, just cut off the one edge and you make sure the top is at the right level. Needs to be a 150 one for size.

 

[UmmYeahOk]

They are a rare float, being a single tab for the needle seat, but the double one can be used, just cut off the one edge and you make sure the top is at the right level. Needs to be a 150 one for size.

what double tab float do you speak of? Where might I be able to get that one?

The ones from the newer carbs I can make fit, but they slide around way too much that they won’t touch the valve unless you position it yourself.

 

[trrdster2000]

Someone may come in to help you on how to bend and area of the pin and the seat tab.
I have give it up for the night, but I have my carbs like you have torn apart and ready for a rebuild, so I can play with a float or two to try and replicate what I did years ago for a buddy. No promises, but will try to give you some direction.
Joe of course has a float or fix if I remember rightly.
Wonder if you can take the floats off this one and put the newer ones on, might have to figure a way to melt plastic. Harbor Freight sales a plastic welding kit.
Sorry I get carried away, well trying to keep them from carrying me away. LOL
Wayne

 

[dklawson]

Wayne is right. I won't say you are screwed but even Joe Curto does not have the floats you need for the early 150 CD carbs.

What Wayne is talking about is the later CD2 floats have a little paddle next to each pontoon float ( 2 paddles). The paddle is what pushes on the plunger of the float valve to close it. The later CD2 floats are symmetrical with 2 paddles so it can be used in either carb. The early CD carb floats only have one paddle so they are not symmetrical.

When my car developed a sinking float I was able to rob one from a spare carb. Anticipating that the other float was likely to fail I bought a later CD2 float to experiment with. I cut off one if its paddles and made a tubular brass spacer. The brass tubing spacer slips over the float's pivot pin to position the float laterally so it sits in the right position in the float bowl. That is where I left my experiment. I have yet to install it in a working carb to determine if the paddle can be bent adequately to set the correct float level. It will take some trial and error work to get that paddle bent correctly.

In the next few days I will try to locate my modified CD2 float and post some pictures of it.

Comparison Photo Links below:
Early CD Float with One Paddle
Later CD2 Float with Two Paddles

 

[UmmYeahOk]

Ok, so I guess I was trying to do what you were, only hadn’t gotten far enough to make spacers. I will contact joe, but probably will end up doing my own spacer experiment. Let me know if yours is successful.

 

[dklawson]

I decided to get the pictures now while I was thinking about it.

The first picture is a standard 150 CD float. Notice it has no brass spacer tube, one paddle (on the right), and that the paddle is directly over the float valve plunger.

The second picture is my modified 150 CD2 float. I have cut off the "left" paddle. The brass spacer can be seen on the left end of the pivot pin. The paddle just barely covers the float valve plunger. Not seen in the picture is the 3-dimensional twist in the paddle to get it to cover as much of the float valve as possible. Further height bending is probably required to get the equivalent fuel level in the bowl as the original float.

EDIT: Sorry UmmYeahOK. I won't be trying my modified float until I experience another sinking/sank/sunk float on our car.

 

[trrdster2000]

Doug, you got it, I'm pretty sure I used a spacer on the pin after cutting the other tab off and I believe I didn't need to cut it off, but been a long time.
Now we are moving in the right direction, may have to put that funny bend in the new one. Between the 3 of us we should be able to come up with the answer.
I did this back in the day when these were our daily drivers, so had to think of stuff on the fly.
Tomorrow ladies and gents.
Wayne

 

[trrdster2000]

Doug, you got it, I'm pretty sure I used a spacer on the pin after cutting the other tab off and I believe I didn't need to cut it off, but been a long time.
Now we are moving in the right direction, may have to put that funny bend in the new one. Between the 3 of us we should be able to come up with the answer.
I did this back in the day when these were our daily drivers, so had to think of stuff on the fly.
Tomorrow ladies and gents. Thanks Doug, the picture explain the whole thing.
Wayne

 

[UmmYeahOk]

I couldn’t wait. I figured I had some metal piping somewhere that I could make a spacer out of, but then realized that I probably had a zillion washer that wouldn’t require cutting. I indeed had some. I had some that were small enough diameter that fit perfectly! I installed it, bending the tabs accordingly. The unused tab I bent upward in order for the pivot pin to go in. The other I bent upward as well which wasn’t as elaborate of a bend as yours in your picture, but got the job done. ...or so I thought. Initial tests, the carb no longer floods! However, it’s starved for fuel, idles low with the pedal to the floor. ...at least there’s no gas everywhere!

Comparing my pic with yours, I guess my angle is just off, and I need to do what you did.

 

[dklawson]

You are quick!

It sounds like you are at the tweaking step I mentioned. Eventually you will get the paddle bent to achieve the equivalent fuel level as the original float. Let me make the suggestion below.

The other carb is still OK so use it as a guide/standard.

Remove the suction chambers from both carbs (4 screws on each, then lift off).
(Mark the carbs so you put the suction chambers back on the right carb).
Look down the jet of the good carb to see how high/low the fuel is in its bowl.
Now look in the problem carb's jet and note the height of its fuel.
(Based on your statements it is probably "low" compared to the good carb).

Drop the float bowl on the problem carb (6 screws from below the bowl).
Tweak the paddle position by bending it "down" a bit.
Refit the float bowl and crank the engine over to refill the float bowl.
Look again in the two jets comparing their fuel levels.
Keep adjusting the problem carb's paddle until the fuel level in both carbs appear to be the same.

When the fuel levels look about the same, refit the suction chambers to both cards and make sure you fully tighten the bowl screws on the problem carb.
Lemon juice may help cut the gas smell on your hands if you aren't wearing gloves.