TR4/4A Cracked Zenith-Stromberg float assemblies

[Merlin63Tr4]

Got a call from a friend about a sudden rich running problem with his ’64 Tr4, strong smell of fuel, sputtering, etc. I told him to stop running it till I got there.
When I got to his place there was a strong smell of fuel inside the garage were he kept the car. So being on the cautious side I told him that we should push the car outside to troubleshoot it.
After starting the Tr it did’t take long to figure out the problem since fuel was dripping out of the front air filter, onto the lower inner fender and the ground….
So we took the front Z-S carb apart expecting a stuck needle valve but instead we found the float assembly cracked wide open! So as a precaution we took the rear carb apart to see its condition and we found another cracked float assembly, not as bad as the front’s, but still cracked.

As far as my friend knows these floats are original to the car (he has owned it since 1967) so they could be 55 years old.

So the car is out of commission waiting for replacement carb floats.
Wonder if the replacement floats will last 55 years…..

M.

 

[glemon]

The floats for these carbs weren't available for a while, they are last I checked, they are supposed to be made of stuff impervious to gas, alcohol, etc. Though I know that the statement in the advertising doesn't make true.

 

[Merlin63Tr4]

Yes, he ordered a pair of float assemblies made of Nitrophyl.

Guess I should check the floats in my carbs.....

M.

 

[Geo Hahn]

Do check them - even if they haven't cracked to the point of total failure they may have a seam that is allowing some fuel into the float. That will cause poor running.

I have even had a partially fuel-logged float that wold cause the engine to die on hard left-handers. Felt like fuel starvation but really if was dumping fuel into the intake and killing the engine.

I now have the Nitrophyl and hopefully 'problem solved' for a long long time.

 

[Merlin63Tr4]

The floats in my carbs are probably ready to crack if they're not cracked already, they are even older than the ones in my friend's Tr4.
I think I will just order new Nitrophyl floats tonight, no use taking the carbs apart and then find out you need parts.....

M.

 

[Gliderman8]

Yes, he ordered a pair of float assemblies made of Nitrophyl.

Guess I should check the floats in my carbs.....

M.

Where's the best place to order the floats from?
Can you post a link?

 

[Merlin63Tr4]

Elliot,
From the checking I did, all the major vendors have them available.
For example;
Tr4 floats
Moss Motors: https://mossmotors.com/float-arm?assoc=49156

Rimmer Bro.: https://rimmerbros.com/Item--i-CDZX1

Tr6 floats
Moss Motors: https://mossmotors.com/float-carburetor-upgraded-nitrophyl?assoc=43336

etc.

M.

 

[dklawson]

Several years ago I had a float sink on our GT6. No one had replacement floats, not even Joe Curto. Fortunately I was able to get a working float from a spare carb I had. These are the 150 CD carbs, not the more common, later CD2 series for which floats are available.

Where did you find the new floats? I can tell from the photos you posted that they are the same style of floats as used on the GT6. However, I assume the TR4 has 175 CDs. I'd like to get some new ones if they are available for the 150 size.

 

[Merlin63Tr4]

Doug,
Yes Tr4s use Z-S 175CD carburetors,
From the quick searching I did, I was only able to locate some floats for GT6 Mk2 (68-72).
Web site did not specify Z-S150CD .

British Parts Northwest:
https://www.bpnorthwest.com/triumph...at-zenith-stromberg-carburetor-nitrophyl.html

Might have to put Webbers on that puppy,,,,,

M.

 

[dklawson]

From the quick searching I did, I was only able to locate some floats for GT6 Mk2 (68-72).

Thanks for looking. Unfortunately that is the same thing I found a couple of years ago. Our GT6 is a '67 so the later floats are not a direct fit.

When the problem happened I ordered one of the later CD2 floats to experiment with. I believe what might work is to use the later CD2 float by cutting off one of the two float valve actuating arms and putting a spacer on the pivot shaft to hold the later float horizontally in the correct position. After that it will take some experimenting to get the equivalent level of fuel in the float bowl.

That's why I used the donor float from an extra carb. I was too lazy at the time to experiment. Hopefully I won't have to take up those experiments anytime soon.

 

[Merlin63Tr4]

Doug,
That's too bad.
Do you know how much smaller the 150CD floats are than the 175CD floats? Could the 175CD floats be made to fit?

M.

 

[poolboy]

Where's the best place to order the floats from?
Can you post a link?

The floats for the ZS carb in the TR4 is different from the float in the TR6 carbs...but Joe Curto has both and shipping will be closer to the actual price and not based on price of items.
A phone call is best...not email.

 

[Merlin63Tr4]

Ooops, finally noticed that Gliderman8 was posting about Tr6 floats.

I have corrected my post by adding a link to Tr6 carb floats

M.

 

[Merlin63Tr4]

The floats for the ZS carb in the TR4 is different from the float in the TR6 carbs...but Joe Curto has both and shipping will be closer to the actual price and not based on price of items.
A phone call is best...not email.

Poolboy,
Sorry for the late response, things got a little hectic around here.
Took your advice and called Joe Curto.
He is the originator of the TR Nitrophyl carb floats.
His floats are around half the price of the other vendors with a very sensible shipping cost.
Thanks for the heads up.

M.