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how to de-dirt SU Carbs ?

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Jer

Jer

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This weekend I was climbing a hill, passing a car (about 65/70 mph) & the car started to sputter & then it would only go about 50/55 mph, I pulled over checked to see if a plug wire came off but it did seem like a plugged fuel filter (have experienced that on other cars before) Then headed off & car was better, decided to check the filter... and discovered the DPO didn't install a filter - anywhere ! (just got this one last fall & never bothered to check)
Since I already had a Facet pump on the shelf, it was a perfect opportunity to replace the original style SU pump & install a filter, this job went fine.
My question is there any quick way to clear the carbs of any dirt that I'm sure has made it's way into them without full removal & overhaul (I'm driving this to Spridget 50th so I don't want any major repairs at this point)
The car seems to run fine but thought if there was a simple way to clean em' up I would just to be sure.
 
Short of pulling the carbs off and dipping them, I'd guess you're "stuck" with just using carb cleaner and lint free rag. Maybe try to wipe from the inside out? You could pull the domes as well without getting into the linkage etc...
 
Can't you just pull the fuel bowls and clean them out?
 
I would think just pulling the float covers, swabbing them out, then applying compressed air would do the job. Lift the slide and blow backwards thru the jet
s as well. Quick and dirty though a good tear down and cleaning would be better.
Probably be a good idea to remove float needles and blow thru there as well.

Kurt.
 
For on-the-car maintenance of the carbs, follow the advice given above.
Work on only one carb at a time. Remove the float bowl lid, use towels to remove the gasoline and debris in the bottom, followed by compressed air. Remove the vacuum chamber from the carb body itself. Carefully remove the piston/needle. Be careful not to drop or bang the parts and put them aside on a clean, dry cloth. Spray carb cleaner down into the jet and feel free to run the plastic spray tube down the jet. Any deposits and debris should end up in the float bowl. Towel dry again and this time blow air back and forth through the jet (both ways). Finally, remove any deposits on the needle itself and reassemble the carb. This should leave your carb clean without affecting the adjustments.

However, before putting this issue to bed you should also give your ignition system a once over. Pay particular attention to the points and condenser. As the points close up due to wear and deposits, they can cause problems with starting and with high-speed running. Remember that 90% of SU carb problems are caused by Lucas electrics.
 
Thanks for all the suggestions, I will investigate as time permits !
 
On SU's, I've removed the fuel bowl lid and cleaned out all the "stuff". Then removed the tops to access the jet. Put on my safety glasses and put the red plastic tube that's attached to the carb cleaner into the jet, covered the fuel bowl and gave it a blast. Cleans out anything in between the jet and the bowl and cleans out the low collection point in the fuel bowl. Remember to wear your safety glasses!!! Can be done in situ.
Will you need a pressure reg. w/ your new fuel pump??? (more of a rhetorical question)
 
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