[TR] TR 250 carb woes

Dave1massey at cs.com Dave1massey at cs.com
Thu Apr 15 09:27:25 MDT 2010


In a message dated 4/15/2010 10:18:52 AM Central Daylight Time, 
sothornton at stevethorntonlaw.com writes: 
> I need your collective help.
> 
> I have a relatively new restoration of a TR 250 and the carbs were
> rebuilt in the Summer of 2008. Since then, the car has run relatively
> care free.
> 
> However, after a few month lay off, I tried driving it in March, only to
> smell a strong gas smell once started. I left the car running, popped
> the hood and determined gas was pouring out of the float bowl of the
> rear carburetor.
> 
> Last night, a friend and I tore down the carbs and found a small amount
> of dirt in the rear carb, installed Grose jets in both reassembled them
> and the same thing occurred in the rear carb only. We then removed the
> carbs, inspected both and adjusted the float to 11/16ths as the rebuild
> kit suggested. Same result. We are baffled about why the rear carb is
> overflowing gas from the rear carburetor. Any ideas of what we do next?
> 
> Many thanks in advance.
> 

The float chamber is vented to a port on the face of the carburetor near 
the main air inlet.  It is important that this vent not be clogged.  Check 
this out for some foreign material such as a cob web or a misaligned gasket.  
If the air can't get out of the chamber the level will never rise to close 
off the float valve and the excess gas will pump through the jet and flood the 
engine.

Dave


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