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As some of you know I've been having a few problems with my TR6. Well here's another one, involving a part that I'm totally useless with - carburettors. Its like I have a mental block with the things.

I've been smelling petrol ever since it came back. I took it to be the change that was made in the back where the tank attaches to the through bulkhead fittings (its custom) and a small amount of leftover gas evaporating, but that's dry now.

Its so bad I can smell it in the house, and it isn't getting any better. SWMBO is making nasty remarks, and you all know how that goes.

She's out tonight, so I wandered out into the garage. The #3 carb (closest to the bulkhead) is soaking wet underneath with, you guessed it, the aforementioned gasoline. Car hasn't run since Thursday.

So here are my dumb questions. Forgive my ignorance.

#1 how hard to fix? The plug underneath is in btw.
#2 what do i need to do to fix it? Please don't tell me I need to pull them, I just can't face it...
#3 i assume it can't be driven until it's fixed (although of course I have).

These are of course newly 'rebuilt' carbs...
/ubbthreads/images/graemlins/frown.gif
 
Not to familiar with your car, are you running strombergs or SU's? If SU's it's probably the seals where the float bowls attach to the main body as they can be 'shaken' loose from driving or just deteriorate. Easy fix try lightly tightening the securing nut.
Note of caution; carbs can only leak the amount of fuel stored in the float bowl area. This will usually disapate pretty quickly and I can't imagine the fumes invading the house so don't assume the wet carb is automatically the problem please check the whole system.
 
Check the line connections to see if that is where the leak is originating. If not there I suspect the float is stuck or not adjusted properly. The plug in the bottom can leak (but not upward). If it is leaking or the float needs adjusting I would think it is a pretty simple "fix" with 2 ZS's; don't know how much room you have with 3 carbs. TR6 Bill is a pro with the three carb set up. He will know how and what to do to make a repair. This could be the rough running problem and poor idle that I think you mentioned before.

A gasoline leak is hazardous so if you can vent it out side you and the other half may find things a little more pleasant before you effect the repair.
 
It's not the lines. Its coming out of the carb itself, the bottom of it (around where the plug goes in) is covered in gas - perhaps I didn't explain that too well.

I'll look in daylight to see where exactly.
 
My rear Stromberg would spew fuel on occasion. I was leary of openning them up as well. I ordered a rebuild kit, bit the bullet and manual in hand found them extremely simple.
They had been recently rebuilt and it turned out the floats were set incorrectly and the needle valves were missing their gaskets. No fuss, no muss or problems since. Phil
 
Alan,
Pull the plugs on the bottom of the carbs and change all three O-rings to black rubber. Instant fix. Got my rings from NAPA. The guy that fixed my carbs used some kind of other rings (a greenish color) and realized now that that doesn't work as well as rubber.

These plugs are plastic (although they look like brass) and pry out with a flat screwdriver. May have to use an adjustable plier, which will score them a bit.
 
OK, I found the name of the material not to use. It's called VITON . Do <u>not</u> use Viton O-rings. Use only black rubber.
 
Alana
You said you can smell the gas fumes in the house. I'm
guessing your car is in the garage. I hope your hot water heater for the house,is not in the garage. That could be disastrous....
Just a thought.
 
Hello Bill,

are you sure?

"Additionally, Viton ® has excellent resistance against water, chemicals, oil and petrol."

Alec
 
Hi Alec,
When I had my ZS carbs rebuilt, the shop that does the work used the absolute best of everything, sourcing all his gaskets from the UK. Simply looking at the three carbs one could see that the materials used were superior to the usual pieces one gets when buying a "rebuild kit" from one of the 3 big vendors over here. The Viton O-rings he installed on the float chamber plugs were supposed to be the cat's meow in O-rings. They lasted (all 3) about a month before gasoline started literally dripping out about the plugs. Frustrated, I called Gary Martin, the rebuilder, and complained loudly. He was as frustrated as I was, stating that the Viton rings were not supposed to do that. He said they were supposed to be an improvement over rubber rings. Since I changed back to rubber, over a year now, zero leaks. All I can say is from experience.
 
Hello Bill,

strange, when I first saw your post I thought that it sounded wrong so I searched for a reference.
Could it be possible that what was installed as Viton may have been incorrectly labeled or some such mix up?

Alec
 
Your carb man may be the victim of something common today. Counterfeit parts and materials. What was sold to him and perhaps his supplier as Viton may be green coloured yak gut or some such crap. This may sound absurd, but this problem is endemic in industry today. One other thought, is to consider the size of the o-ring , ID, OD and cross-section. The wrong size may have been supplied. One reason the rubber rings may be performing better is their tendency to swell and soften in the presence of petrol.
 
I just went outside again to look at it. It's leaking from around the gasket that seals the cover for the floats. (Hope that makes sense). Looks like I'm going to have to pull the carb to fix it.

Great rebuild job...
 
Alan, methinks you can get to those without removing the carbs, from the bottom with a short screwdriver. You just don't want any women or small children within earshot.
 
I cant get to it that way. Tried, no dice. Too much in the way.

It gets better. I just tried to pull the rear carb - can't get a wrench on the 4th bolt because the stupid throttle cable linkage gets in the way.

Try to pull the intakes as a set instead. Can't do that because the mechanic in his infinite wisdom has used hex bolts on the two outermost acorns and I don't have a 5/16" allen wrench.

I also found that it's poured out enough gas to melt the paint on the bulkhead underneath the carb, so it's clearly not a new problem. That and on inspection I see that the carbs are now CD2s, not the CS2SEs that I had on it has put me in a fine mood.

I'm very frustrated. I'm trying to give it a fair chance, but I'm so fed up of the whole thing I can't even use the right words - Basil will ban me for profanity.

It's just not worth it any more. Time for a new approach.
 
As Bill says, if you have room to get your hand and a stubby screwdriver under the carb, you can take the bowl off without removing the carb. There are 6 slotted screws, and as long as they are not stuck on too tight to free up, just undo those screws and the bowl can be removed.

Better put something underneath to catch whatever gas is still in there and will spill out. Also the float pivots freely in its bracket, and when you remove the bowl it will naturally swing down towards you. Just be careful not to bend where it mounts or damage the float somehow. It does not have to come out, it will just hang there when the bowl is removed.

Also, there are 4 long screws and 2 short screws (of course) that hold the bowl on. Just make sure the 2 short screws go back where they should go when reassembling.

Once the bowl is out, you can also get at the bottom plug from above a little easier to pop it out. I would replace the o-ring on that just on spec.
 
oops. Guess I should have looked at page 2 of the posts before sending my note above. Looks like you're snookered. Bummer.
 
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