Hot Start Cable Plunger Stuck

Pulled the bike ('04 WR450F) out of the garage to fire it up & give it a "once over" this weekend. Bike had sat up on stand with battery tender connected & carb bowl drained for the last 4 or 5 months, everything was cleaned & lubed right after last ride.

Took a few tries, but started in under a minute on the button & seemed to run just fine (up & down the alley at least). When I was done aggravating the neighbors (YZ pipe) I shut off the petcock & made one more pass up & down the alley to burn most of the fuel left in the carb. I will usually let it idle on the kickstand until it quits, & then re-start using the choke &/or hot start lever to burn the last of the fuel away so that it does not varnish up the carb internals.

Went to pull back the hot start lever & it would not budge. :bonk: I traced down the cable starting at the lever to check for kinks & could find no obvious issues. After unscrewing the zip-ty racing hot start cable nut from the carb body & closing the cable sleeve adjuster all the way down, I finally freed the cable end from the plunger by rooting around in the carb recess with a pick.

There was a decent amount of white corrosion build-up around the top of the plunger, which was keeping it from moving upwards in the plunger bore. after much soaking with carb cleaner & fiddling with a pick I was able to free the plunger from the bore, but not before breaking off both of the extensions on top of it that grip the end of the cable. :ride:

I've ordered a new plunger, seal, & spring (the cable seems to be fine) & hope the parts arrive soon.

Has anyone ever had a similar experience? The only reason I can come up with for this happening would be if when I lubed the cable after the last ride I displaced some water that had gotten into the the cable sheath down into the carb. I guess from now on I'll disconnect the cable before lubing after a wash.:thumbsup:

Does happen from time to time. Soak with PB blaster. Some have had to use a slide hammer to get the plunger out though time and PB may do it too.

You are also proably right about the wash. Run the bike till real hot to boil away traces of water. Or just geive it a real good service before hibernation time.

Had this same thing happen to me a few weeks ago :thumbsdn: Didn't ride the bike for a few months, now the lever is completely frozen. I guess I will have to give it some PB for a few days to see if I can get it freed up. Any other suggestions??

Does happen from time to time. Soak with PB blaster. Some have had to use a slide hammer to get the plunger out though time and PB may do it too.

You are also proably right about the wash. Run the bike till real hot to boil away traces of water. Or just geive it a real good service before hibernation time.

What is a slide hammer?

Take the plunger out, polish the bore in the carb with a tshirt and metal polish, and coat the sides of the new plunger with anit-sieze.

What is a slide hammer?

If you do not know, take the carb to a pro to have them remove the plunger.

My carb is fine, I just have never heard of a slide hammer before. I probably know what it is, also probably own 1 or 2, just probably call it by another name. I'll google it.

Update for all those who have had this problem...or will in the future.

Remove the carb

2013-04-13143629.jpg

I soaked this thing with PB for a few days, but it would not budge. So, drill hole and insert screw.

2013-04-13152845.jpg

Next the bore will be cleaned and polished prior to inserting the new parts.

2013-04-13152823.jpg

My hotstart has been stuck for years (probably about 5), but I never use it anyways so I have just left it. It always starts just fine when hot.

My hotstart has been stuck for years (probably about 5), but I never use it anyways so I have just left it. It always starts just fine when hot.

I have removed the hot start on the last three 450s I've had owned and never had a problem starting them.

My hotstart has been stuck for years (probably about 5), but I never use it anyways so I have just left it. It always starts just fine when hot.

I don't use mine a lot, but when I need it, it sure is nice to have. :thumbsup:

To finish this off and for completeness. Using my dremel I lightly polished the OD of the bore and then installed the new parts with some anti-seize. Good to go :thumbsup:

a90cfc26-7586-423f-a6d1-b19c919d9c28.jpg

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