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MG TD TF 1500 - Help with MG TD Carb Jet Assemply

Hi,

I bought two new jet assembly from Moss, having some issues with the jet moving up and down freely.

I believe the washers for the jet seal are installed with the concave surface against the jet gasket, is that correct? The problem I'm having is after I install the assemblies, the jet is not moving freely up and down, will jam up against the washer. BUT if I flip the washer over so the flat side is against the jet seal that immediately solved the problem, except now I'm getting gas dripping from the jet.

So, what's up?

Steve
SD Denham

Yes, the concave 'cup' goes against the cork washers. These washers crush the cork into the jet, hence your reduced ability to slide them.

Did you soak the cork washers in oil for 24 hours prior to installing them?
Kevin McLemore

Steve, they must be soaked in oil for a couple days before installing them. Try to have the oil room temperature or a little warmer, also make sure the concave side of the washer is against the cork. It helps if the jet is polished too, it needs to be as smooth as possible. I went through all of that, but my carbs were too wore out and I had to send them out for total rebuild, their not back yet.PJ
Paul161

Thanks, I found a schematic that did confirm the placement of the washer. The seals that came with the new jet assemblies were those neoprene ones that I hear on other threads a lot of owners don't like. I think I have one cork spare and can maybe resoak a used one and see what happens. My hypothesis is that the washer isn't sitting perfectly flat, so even if there's a very slight angle to it that is what is blocking or inhibiting the jet. Oh well I'll keep trying!
SD Denham

Check the thickness of the top jet holder to carb body copper washer. I think that is the one that is too thick on some of the kits, and that may lock up the jet? Easy to test- loosen the big nut a bit and see if the jet moves freely. I would use Teflon O-rings rather than neoprene, they have worked well for me though some have had issues. Also, make sure the jet is free before putting the chamber/piston/needle on. George
George Butz

George is right, check the washer on the top. It should be 0.015 thickness, some are more than double that. This will cause the engine to run too rich if they are too thick. I have used the cork without issues, but soaking in oil is CRITICAL, I installed a set that hadn't soaked long enough and had to replace them later.
Geoffrey M Baker

While you have the carbs on the bench you might want to check that the butterflys are not installed backwards like mine were! Impossible to set the idle properly that way. They are beveled on one side only.
Ed
efh Haskell

Thanks for all the feedback, I just can't figure it out. I'm going to buy a new set of seals and gaskets and see if I have the same issue, only a few dollars so not an expensive experiment.

Steve
SD Denham

This thread was discussed between 26/10/2015 and 31/10/2015

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