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SU rebuild

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jscott

jscott

Freshman Member
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I'm rebuilding the SU's on my 1959 tr3a and need to
know which way the cupped washers goes on the jet bearing.
Does the cupped part of the washer go against the spring or
the gland seal( cork seal)? Is it suppose to look like this,
( spring ) or turned away from the spring? I hope this
makes sense. Thanks

Jim
 
Thanks Dave. I assembled it with the cupped side toward
the spring. Now the car won't start. It's flooding like
crazy. It's been driving me nuts for 2 weeks. Thanks
again Dave.
Jim /ubbthreads/images/graemlins/thumbsup.gif
 
Jim, I am not too sure that the flooding is due to these seal retainers, more likely to cause a leak. A great place to start after a carb re-build is to pull the dash pots&pistons off the carbs bring up the fuel pressure(spin the motor)Now the floatbowls will be full and the float needles (if seated ) have stopped fuel from getting through.
At this time look at the main jet and visually confirm the fuel height in the jet. It should be 60 to 90 thou below the level of the carb bridge. If its flush its too high and you will flood like crazy. If gas over flows when cranking, your floats are not stopping at the correct height.
MD(mad dog)
 
Thanks Mad Dog, I'll check it out. If the fuel level is too high at the jet, what is the fix?
Jim
 
Hi Jim,
The cups are designed to squeeze the top cork against the top jet bearing & the bottom cork against the bottom jet bearing. The tapered cup also compresses the cork inward to seal around the sliding jet. It certainly won't hurt to have it correct.

If you still have trouble, MD is correct about how to check things;
A common cause of the float level being too high is leaving out the fiber washer between the float inlet valve seat & the carb body. Sometimes this little sealing washer is left out of the rebuild kits or just gets lost.

You should have the H4 carbs. The float level is set by placing a 7/16" diameter rod between the inverted carb top & the forked float lever. The arms of the lever, at the height of the curved point, should "just" touch the rod when the small spring spring loaded plunger in the inlet valve is "NOT" compressed. I think the same setting applies if you have the Grose type ball valve with no spring loaded plunger. If necessary, carefully bend the float arms to fit. But make sure that the sealing washer is between the jet & the carb body first.
D
 
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