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fcr merge ap spring help?

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Ok,

I am one of the lucky ones and got the FCR in this last go round and got the merge fuel screw and the AP spring.

Well I have been trying to find a how to on the spring replacement and the one I found the pics do not show up. I think I can do this change with some pics in the how too.:p

Any help would be greatly appreciated

:ride::moon: :moon: :lol::p:banana:

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In a nut shell

Spread a clean white towl on your work bench

Remove the float bowl

Use a small jewlers screwdriver, pop the AP shaft from the black plastic AP cam

Remove the AP cam 'E' clip and washer

Remove the cam and the old spring

Install the new spring and the cam. This is a pain in the A**. Take your time. Think. Be gentle.

Install the washer and 'E' Clip

Press the AP rod up from the bottom of the carb till the 'knobbed end' snaps into the cam.

While the float bowl is off, carefully drill the fuel screw opening with a sharp 1/4" drill bit. Finish smoothing the hole with a peice of rolled up emery cloth.

If you have to swap jets (main/pilot) do it now.

Reinstall the bowl, install the fuel screw and set it to two turns

Remove the slow air jet from the carb mouth, install the carb bell

Check/change the needle

Install the carb.

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Wow... William, you just made up my mind. I'm going to buy some o-rings today!! :p

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In a nut shell

Spread a clean white towl on your work bench

Remove the float bowl

Use a small jewlers screwdriver, pop the AP shaft from the black plastic AP cam

Remove the AP cam 'E' clip and washer

Remove the cam and the old spring

Install the new spring and the cam. This is a pain in the A**. Take your time. Think. Be gentle.

Install the washer and 'E' Clip

Press the AP rod up from the bottom of the carb till the 'knobbed end' snaps into the cam.

While the float bowl is off, carefully drill the fuel screw opening with a sharp 1/4" drill bit. Finish smoothing the hole with a peice of rolled up emery cloth.

If you have to swap jets (main/pilot) do it now.

Reinstall the bowl, install the fuel screw and set it to two turns

Remove the slow air jet from the carb mouth, install the carb bell

Check/change the needle

Install the carb.

I have to drill a hole?? OMG

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LOL, no, not drill a hole, what you are doing is opening up the existing hole in the float bowl a smidgeon. This to enable the fuel screw to fit through. The complete job I outlined about takes ten minutes. Covers both doing the spring for the AP, preparing the carb for an extended fuel screw and ensuring jetting is right before you install the carb.

A oring is fine as long as you do not mind checking it regularly and replacing it as it begins to fail. The spring is a one time job.

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LOL, no, not drill a hole, what you are doing is opening up the existing hole in the float bowl a smidgeon. This to enable the fuel screw to fit through. The complete job I outlined about takes ten minutes. Covers both doing the spring for the AP, preparing the carb for an extended fuel screw and ensuring jetting is right before you install the carb.

A oring is fine as long as you do not mind checking it regularly and replacing it as it begins to fail. The spring is a one time job.

Okies, but this is all new to me and I so don't want to screw this thing up after the $$. and I think a visual will help

Thanks for the tips :p

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Its no big deal.

My APS came with an instruction leaflet.

With those instructions it took me 10 minutes.

The only thing is to carefully 'click' the rod in and out of the joint-cup in the rod. That feels like you may be using a little too much force.

I did not have to drill anything.

No biggie.

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Thanks Debi for asking this and William for the excellent response ,as always. My AP spring and Keintec ex. fuel screw should be here very soon and I was just going to wing it, but now I at least have no excuses if I fubar it.

William(or anyone else that knows) : I thought the fuel mix. screw hole opening only needed to be drilled out on non-MX FCRs though, but does the MX FCR 39 need this mod as well? Thanks

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I rec. doing it to all FCRs. You have the carb and bowl off to install the spring,.

With opening drilled to 1/4", you can add a second oring to the screw mid shaft. This will provide additional friction to the screw, preventing it from ever vibrating out.

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I have to drill a hole?? OMG

It sounds a lot worse than it is...lets hook up on Friday and I will help you. I PM'd you with my number. I will send you some info on the choke lever clearance on your Clarke tank. Don't drill any holes in your carb until I get there...LOL.

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What size "O" ring on the fuel screw do I need?? or should I just take it to the hardware store with me to find one?

Again. Thanks everyone:thumbsup:

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Assuming you are looking for a second one for the shaft, then matching up at the hardware store will be Ok to do.

If you are replacing the exisiting one, you are better off at a dealer. I think both Yamaha and Honda sell them seperately. Any MX bike they sell that uses the FCR, it'll be in the fiche, may take some poking to find.

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The Merge Fuel screw comes with the washer, fuel screw spring, and O-ring.....you will just need the O-ring for the freshly drilled out port that goes over the middle of the fuel screw.

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The Merge Fuel screw comes with the washer, fuel screw spring, and O-ring.....you will just need the O-ring for the freshly drilled out port that goes over the middle of the fuel screw.

So just take that with me to like the hardware store??

Yes I know I'm a pain in the :):banghead:

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Just take the float bowl that is drilled out slightly and the fuel screw and find a o-ring that fits over the middle of the fuel screw and also fits in the redrilled passage way of the float bowl...it just rubs slightly on the passage way to help support the fuel screw...otherwise the only thing that holds the fuel screw in are the threads of the fuel screw. The extra support in the middle of the screw helps it to not get loose and unscrew....I hope this makes sense.

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