Red Loctite on fuel mixture screws.

[Chris Bock]

I've a rack of Mikuni's from a GS1000G. Did a complete tear down/carb dip/blow out/reassemble. Was not able to remove the fuel mixture screws before or after the dip. I could see that they were completely covered with Red Loctite.
I've used carb cleaner, bolt blaster, other penetrating oils, a "Dental Pick", and a heat gun.
Was able to get the visible Loctite out with the pick.
Tried alternating carb cleaner and penetrating oil, with the heat gun hitting the screw well in between.
Filed a flathead driver to fit the slots off the screws.
Not a single budge.
I'm about to drill the screws and use an EZ-Out, but thought I'd post this first.
I've searched through the forums, but didn't find anything that resembles this situation.
Thanks

 

[Chris Bock]

Feel like an ass now. Was able to remove the fuel mixture screws on the Mikuni bs34ss's tonight.
Left them with bolt blaster in the mixture Wells overnight.
Heated up the aluminum screw well, and was able to start turning them in (clockwise) bit by bit. When they were all seated, sprayed some carb cleaner in the wells, and let them sit for an hour. Blew them out, and filled them with penetrating oil.
From there, I just started backing the fuel mixture screws out until they would get stuck. Screwed them in, more penetrating oil, heat gun, then back out further.
Once the screws would back in and out, to a certain point, I used an electric impact driver (slow, with constant downward pressure) to clear the screws through the final threads.
So, patience and persistence, carb cleaner, PB blaster, and a heat gun are the answer

 

[dorkburger]

No need to feel like an ass. You took your time and got it done without damaging anything. You likely saved yourself loads of aggravation and money by taking it slow.

 

[rphillips]

Great to hear, Feels good don't it? Many, probably most, would have not been so patient, got aggravated & buggered something up. Congrats, well done.

 

[Nessism]

Great job! This should be a sticky! I wish more people would just stop when the screws won't come out with reasonable force. That would save tons of carbs from the graveyard.

 

[TeamDar]

To remove red Loctite it is best to heat the area to 400-500 degrees F. A don’t know if a heat gun would get the area that hot. Usually a torch works well. If you just heat it until you get a puff of smoke from the screw you are usually good. Aluminum melts at 1200 degrees F. so you can do this without hurting the carburetor. Dar

 

[robertbarr]

Makes me wonder what kind of sick saboteur would put red loctite on mixture screws...

 

[Chris Bock]

Good temps to know for any future projects!

 

[Guest]

Might not have been Loc-Tite. Glyptol is used as a 'sealer' for some electronic components to show whether they have been tampered with. Red Glyptol looks a lot like Loc-Tite.

 

[Chris Bock]

Good to know. I extracted the plugs and removed the fuel mixture screws from a crusty old parts bike (same year/model) and they came out lickety split! No red anti-tamper or Loctite. I think this was just a parting gift from the PO.

 

[Chris Bock]

Thanks, all, for the replies and support. Working out problems on bikes is half of the fun for me (the other half is riding them, of course).
Keep it shiny side up, y'all!

 

[bwringer]

Makes me wonder what kind of sick saboteur would put red loctite on mixture screws...

Might not have been Loc-Tite. Glyptol is used as a 'sealer' for some electronic components to show whether they have been tampered with. Red Glyptol looks a lot like Loc-Tite.

We can only hope it was something other than red Loctite, but then again we've all seen much dumber stuff perpetrated by POs. When my GS850 came to me, quite a few fasteners were slathered in a mysterious hardened gray glop.

To remove red Loctite it is best to heat the area to 400-500 degrees F. A don’t know if a heat gun would get the area that hot. Usually a torch works well. If you just heat it until you get a puff of smoke from the screw you are usually good. Aluminum melts at 1200 degrees F. so you can do this without hurting the carburetor. Dar

Carbs are made from a zinc alloy, not aluminum. Much lower melting point, so far more care is needed if you're using fire.

I've used a soldering gun to concentrate heat on stuck screws, or screws glued in place with mystery glop. Heat guns are useful for heating the whole thing to get a stuck slide out, but you need more concentrated heat for fasteners and adjustment screws.

 

[KEITH KRAUSE]

Thanks for sharing your fix.
There seems to be no limit to what some PO's do. Why would anyone apply sealant to these screws?

 

[Nessism]

Carbs are made from a zinc alloy, not aluminum. Much lower melting point, so far more care is needed if you're using fire.

VM carbs are indeed zinc. BS CV carbs are aluminum though. Huge difference in weight - several pounds.

 

[Nessism]

Thanks for sharing your fix.
There seems to be no limit to what some PO's do. Why would anyone apply sealant to these screws?

Suzuki, or maybe Mikuni, applied paint over the top of the pilot screws on VM carbs. Commonly visible on the air scews. It doesn't lock the screws in place, but it certainly makes removing them more difficult than otherwise would be the case.

 

[KEITH KRAUSE]

Suzuki, or maybe Mikuni, applied paint over the top of the pilot screws on VM carbs. Commonly visible on the air screws. It doesn't lock the screws in place, but it certainly makes removing them more difficult than otherwise would be the case.

Yes, I knew about the factory applied sealant on the CV's mixture screws and the VM's pilot fuel and side air screws. It was applied to try to stop emissions tampering. It sure made a lot of owners frustrated over the years.

 

[Chris Bock]

I?ve set the fuel mixture screws at 2 turns out. That?s just for preliminary work for getting the carbs adjusted. I have a CarbTune Pro, and set the #2 & #3 butterfly?s at 5 cmHg marks below the outer cylinders. I haven?t tuned carbs on a bike with a stock airbox setup before, but the shop guide says that is the correct balance. Still getting some popping during deceleration. I?m getting a ColorTune soon, and will dial in the mix screws. Should I balance the carbs evenly? Or follow the shop guide recommendation? I can mess around, and find out. But any insight beforehand is appreciated

 

[mustangflyr]

Prior to the last rebuild of my carbs I purchased a bottoming tap to make sure the threads for the mixture screws were good to go. Use a M6X.5 bottom tap.

 

[Chris Bock]

Good call. If there?s still gunk at the bottom of the threads, that could give a false seating for the mixture screws.
Still waiting for the ColorTune to come in, and looking forward to try it out.
Plugs look decent now, maybe a little lean, though.
Unfortunately, it looks like I have a blown seal or gasket, though.
Gray/white smoke from the exhaust. Not a lot, and it decreases when revving. Any thoughts from the community?
Not looking forward to pulling the head, but I might as well replace the valve seals, and lap them.

 

[KEITH KRAUSE]

I'd balance the carbs per the factory recommendations, as you said you did.
As for the exhaust smoke, did you do any other work besides the carbs? How many miles on the motor and has it been sitting long or had a history of infrequent use?
The valve stem seals get hard over time. Also, the more the bike sits between runs, the harder the seals become. If it smokes more at cold start up and the smoking decreases as the motor warms up then that suggests worn seals.
This happened to my '79 GS1000 over time. I decided on seals from APE. They claim they won't harden like the stock seals do. Rapidray, a member here, suggested them too. I also decided on having him service the head while installing the seals. Saved me some money compared to having APE do the work. I don't know if APE sells seals for your model. I bought mine in 2018 for about $80 for the set.
Just be sure your oil level isn't high first.