removing medallion 049 backplate

Tinker Terry Sun Nov 16, 2014 10:27 pm

How do you get the backplate off an 049 medallion. Mine has never been removed in over 40 years and none of my cox wrenches seem to fit. What do I need for a tool that won't damage the backplate? Would heating the crankcase help to loosen it?

Mark Boesen Sun Nov 16, 2014 10:46 pm

yes, heat is the key, get'er pretty warm (uncomfortable to touch) and use the edge of wrench, should open pretty easy.

microflitedude Sun Nov 16, 2014 10:50 pm

My preferred method is fitting an older TD wrench in the slats and unscrewing it. Don't use the standard black ones, they are too thin and will bend. If you think it's sticking, soak the engine in your solvent of choice (remove the carb body) for a few days first. Applying heat will help if there is sticky castor in there. Remove the needle so you don't bend it. Hold the engine the engine in a rag to insulate from the heat and provide a better grip. Don't let the wrench slip and ruin the slats. If you feel like you're using too much force, go back to more soaking and similarly more heat.

Edit: Mark beat me to it with the simpler version, but you get the idea. Smile

removing medallion 049 backplate 2014-110

dckrsn Mon Nov 17, 2014 4:45 pm

I agree with Matt and Mark above, but one thing I do is a little different.
I put the wrench(like Matt's above) flat between the jaws of a vise.
Not having to hold the wrench seems to add a little more leverage.
Takes the challenge out of the job.
Bob

ian1954 Mon Nov 17, 2014 5:23 pm

If you are going to apply heat - take off the venturi. Don't melt the delrin!

getback Mon Nov 17, 2014 5:30 pm

and you can do this (but bee careful not to break the TITs! ) Getback Cold

removing medallion 049 backplate Wp_20116

balogh Mon Nov 17, 2014 5:31 pm

microflitedude wrote:My preferred method is fitting an older TD wrench in the slats and unscrewing it. Don't use the standard black ones, they are too thin and will bend. If you think it's sticking, soak the engine in your solvent of choice (remove the carb body) for a few days first. Applying heat will help if there is sticky castor in there. Remove the needle so you don't bend it. Hold the engine the engine in a rag to insulate from the heat and provide a better grip. Don't let the wrench slip and ruin the slats. If you feel like you're using too much force, go back to more soaking and similarly more heat.

Edit: Mark beat me to it with the simpler version, but you get the idea.

It is exactly this wrench that is needed, but use the round end with its internal teeth stuck in the slats of the backplate as if removing a glow head...the bacplate and the glowhead have similar diameters..maybe you do not even have to apply heat..and yes, remove the NV to prevent it from bending..

roddie Mon Nov 17, 2014 5:48 pm

You could also try finding a suitable steel flat-washer.. and mounting it 1/2 in a bench-vise. Even a (solid) Copper penny might work. The radius has a self-centering effect on that style nut, which will help keep it from slipping. It might also save your knuckles.. as long as they're away from the vise-jaws.