• Hey Guest!
    British Car Forum has been supporting enthusiasts for over 25 years by providing a great place to share our love for British cars. You can support our efforts by upgrading your membership for less than the dues of most car clubs. There are some perks with a member upgrade!
    **Upgrade Now**
    (PS: Upgraded members don't see this banner, nor will you see the Google ads that appear on the site.)
Tips
Tips

Z/S carb leaking copious amounts of petrol

Share this page

coryandtrevor

coryandtrevor

Freshman Member
Offline
Just like Cory and Trevor (on Trailrer Park boys) I messed up. My first post accidentally went to the Midget area. Oops! I intended the Triumph area of course. Here we go again!! I recently changed the carbs on my six. One of them is leaking. It seems to do it on start-up. I'm not sure if it's happening as I'm driving (smells like it), and I know it's not leaking while the car is off. I also think that I may detect the pleasant odour of gas in my oil. Again, not sure. Any ideas?? Any assistance would be most appreciated. Thanks
 
My Strombergs were leaking at that brass plug on the very bottom of each carb. I unscrewed the brass plugs, and replaced the old rotten "O" Rings, and problem was solved.
So that would be a place to look for leaks if you're finding puddles of petrol in the driveway.

I've also heard that if you "flood" the motor, the fuel can "overflow" thru the carbs. So if you've flooded the engine a time or two, that could explain the apparent leak, and the smell of petrol in the oil.

my 2¢ worth
 
If your engine oil smells like gasoline, DO NOT CRANK THE ENGINE until you change the oil. Yes, they can and will blowup...at least blow the oil pan off right over the bolt heads.
 
The brass float chamber plug o-ring is 1st option. It pries out in a second, o-rings are available at good hardware stores,plumbing supplies or bearing wholesalers. Before slipping the plug back in tho, give the o-ring a small dab off vaseline or thin grease. It seats in better. Another spot,at least with me, was the choke/cold start valve. Mine leaked only when I had the choke on. Inside, it had a burr on the shaft that the disk was hanging up on. Clean & polish. Here's the link for the ZS bible. Generally I'm useless with carbs, thank God for fuel injection, but I just rebuilt mine with no problem. As a starting point, on start-up, with the choke on, just get a finger on the bottom of each carb and see if they're wet.

Good luck, Steve
 
Seeing you've rebuilt the carbs (just did it myself last week) the chances are you've got thr fuel level in the carb bowls set too high, this is controlled by the floats which have a brass tab that presses on the needle valve when full. Try adusting the float level. I readjusted mine the 2nd time without taking off the carbs again, just unscrewed the 6 bowl retaining screws and checked how full the bowls were, one was obviously too high and I adjusted by guess but got it about right.
 
Back
Top