Intake boot removel help

[egent]

I removed the carbs last night as I was having issues running and with a vacuum leak. I was working on removing the intake boots today. I was able to get boot #1 off. I got one screw out of boot #2. However one screw on boot #4 broke the head off. I can't figure out how to get the impact driver to the screws with enough room to swing a hammer to hit the impact driver. Any guidance would be greatly appreciated, any help will be repaid with food and beer.

 

[tomm]

There seem to be quite a few horror stories about trying to get those screws out. I guess I was just lucky.
I used a cordless drill that had an adjustable torque setting. Put the correct sized phillips head driver into the drill, set it to a fairly low torque setting (about 8 out of 24), and let the drill act as as an impact hammer. Then raised the torque setting one notch and did it again. All the screws loosened and came out smoothly with the torque setting at about 12. (From experience, I know that somewhere between 15 and 18 is where I strip the screw head.)
Won't help you for the screw with the broken head (you'll need an easy-out for that), but might help with the rest of them that are still stuck.
Hopefully you can borrow a suitable drill if you don't have one yourself.

 

[Nessism]

Come in from the side with vice grips and grab onto the outside screw - crack the outer screws loose on the two outside boots. Remove the outside screw and then grab the entire boot with your hand and turn it counter-clockwise which will crack loose the inner screw. Once the outside boots (No. 1 and 4) are off, have a go at the inner two. Worked for me.

 

[Guest]

To do this job, i remove the whole engine.

No kidding.

Too many times the bolts snap, or strip. Just remove the engine real quick and then you hit them with the impact.

 

[hampshirehog]

And replace them with quality allen screws.

Wally

 

[egent]

Update

Update

I have been able to get boot #2 off by twisting the boot to start loosening the screw. Boot #4 is also off, I get the inside screw off with the impact driver. I still have about a 1/4 inch of the outside screw sticking out. I am going to try to grab it with some Chanel locks and get it twisted out, in the mean time I am soaking it down with Deep Creep. I still have not been able to do anything with boot #3.

I want to thank everyone for their suggestions to date. I do have the set of bolts and o-rings to replace from Robert Barr from his site.

 

[egent]

Second Update

Second Update

Well, I have gotten all the boots off the bike. I however now have 2 screws that have broken off. Top screw on intake #3 And top of intake #4. The way I look at it, I have 3 options I can think off. They are:

1) Find someone with a portable torch, as I have non, to heat the aluminum up to cherry red and try to turn out the screws with vice-grips on the nubs of the screws left sticking out.

2) Cut the nubs of the screws off and try to drill the screws out and tap the holes to hold new screws.

3) Try to find another 750 8-valve head and to replace the head. However going that rout, I might as well take to hole engine appart and rebuild the whole things as it currently has 45K miles on the bike, I am not sure it is worth that much.

I am looking for advice on these options, or suggestions of other options. I have a dremel with flexable shaft that I could most likely get in to drill with, but I am not sure if that is the best route at this point. [-o<

 

[TheCafeKid]

Come in from the side with vice grips and grab onto the outside screw - crack the outer screws loose on the two outside boots. Remove the outside screw and then grab the entire boot with your hand and turn it counter-clockwise which will crack loose the inner screw. Once the outside boots (No. 1 and 4) are off, have a go at the inner two. Worked for me.

Good advice Nessim i used it and it went easy as PAHH

 

[TheCafeKid]

Well, I have gotten all the boots off the bike. I however now have 2 screws that have broken off. Top screw on intake #3 And top of intake #4. The way I look at it, I have 3 options I can think off. They are:

1) Find someone with a portable torch, as I have non, to heat the aluminum up to cherry red and try to turn out the screws with vice-grips on the nubs of the screws left sticking out.

2) Cut the nubs of the screws off and try to drill the screws out and tap the holes to hold new screws.

3) Try to find another 750 8-valve head and to replace the head. However going that rout, I might as well take to hole engine appart and rebuild the whole things as it currently has 45K miles on the bike, I am not sure it is worth that much.

I am looking for advice on these options, or suggestions of other options. I have a dremel with flexable shaft that I could most likely get in to drill with, but I am not sure if that is the best route at this point. [-o<

See with that dremmel if you can grind a slot for a flat head screwdriver into it...all you gotta do it get it broke, it will come out cake from there. Breakin em loose is the hard part.

 

[Nessism]

Well, I have gotten all the boots off the bike. I however now have 2 screws that have broken off. Top screw on intake #3 And top of intake #4. The way I look at it, I have 3 options I can think off. They are:

1) Find someone with a portable torch, as I have non, to heat the aluminum up to cherry red and try to turn out the screws with vice-grips on the nubs of the screws left sticking out.

2) Cut the nubs of the screws off and try to drill the screws out and tap the holes to hold new screws.

3) Try to find another 750 8-valve head and to replace the head. However going that rout, I might as well take to hole engine appart and rebuild the whole things as it currently has 45K miles on the bike, I am not sure it is worth that much.

I am looking for advice on these options, or suggestions of other options. I have a dremel with flexable shaft that I could most likely get in to drill with, but I am not sure if that is the best route at this point. [-o<

How much bolt is sticking out of the head? If you have a good sized stub, try the vice grips again. Hit the screws with PB Blaster first and let them soak for a couple of days. A cheap propane torch can be purchased for about $15 so you might want to heat the screw first (not the aluminum).

Good luck.

 

[tconroy]

I just take a small piece of wood and put it on the flange of the boot and tap in the direction to loosen the other screw.Works every time. you can always get one screw loose but usually the other is stubborn.

 

[egent]

See with that dremmel if you can grind a slot for a flat head screwdriver into it...all you gotta do it get it broke, it will come out cake from there. Breakin em loose is the hard part.

My concern with doing it that way, is I don't have much of the screw sticking out, and I don't want to break the little bit off and end up having to drill till I am sure that is the best way to go.

 

[egent]

heat the screw first (not the aluminum).

Good luck.

I thought the idea of heating was to heat the outside metal (in this case aluminum) to expand it away from the screw that is stuck inside, there by loosening the stuck screw. Someone correct me if I am wrong.

 

[Nessism]

I thought the idea of heating was to heat the outside metal (in this case aluminum) to expand it away from the screw that is stuck inside, there by loosening the stuck screw. Someone correct me if I am wrong.

My understanding is that the heat helps break down the chemical bond holding onto the broken screw stub. Some people bang on the broken screw with a hammer after heating to further upset the bond.

 

[Guest]

I thought the idea of heating was to heat the outside metal (in this case aluminum) to expand it away from the screw that is stuck inside, there by loosening the stuck screw. Someone correct me if I am wrong.

That's my way of thinking too. Aluminum expands faster than the steel screw.

 

[Roostabunny]

Hard to believe

Hard to believe

Can't help an more than previous posts on the broken screws, I've got a strange experience with getting those screws loosened on my bike.

I had a mechanic friend helping me the first time I pulled the carb boots off my GS850 hunting down my intake leak. After we struggled with the same problem of not enough space to swing a hammer at the impact driver he tried a trick that made me really nervous but worked.

He took a chisel punch, aligned it on the edge of the screw head from the side, and struck it so that he actually got the screw turning. Kind of a glancing blow.

Now this guys been a bike mechanic for well over 20 years, so he probably had a back-up plan. But to my amazement not only did it work, but the chisel damage to the screw heads was minimal. Since I was planning to have the carbs off again in a week (couldn't find the right size o-rings that night) I just put them back in. Then I planned my route home the next day to go by both NAPA (for the o-rings) and Ace (for hex head replacements).

I guess I can't really recommend this method in general, but having seen it work and having a vague idea of the physics that made it work, I'd try it again myself as long as I was comfortable with my, uh, Plan C. Either way, in the interest of adding to the general knowledge, there it is.

 

[TheCafeKid]

That's my way of thinking too. Aluminum expands faster than the steel screw.

I remember something about this in chemistry class....and if i remember right heating the aluminium isnt going to work because its not just going to expand outward....the hole will expand inward...we heated a steele donut more or less and the question was with the donut hole get bigger, get smaller or stay the same diameter...and...i cant remember...but it stands to reason it would get smaller cos its all expanding...does that make sense?

 

[spyug]

Roost, it is interesting that you mention that trick as I have seen my pro wrench do that as well. I had a set of carbs on my old Virago that had one screw in the float bowl that the screw driver slot was buggered by the PO. I couldn't see how to buge it but the wrench did exactly as you described and out it came.

Now I was trying to get my intake boots off but couldn't budge any of the screws so gave up as I was afraid I'd end up as most do with the screw head busted off. I forgot about this little trick. I should give it a try.

Good piece of information.

Cheers,
Spyug.

 

[Roostabunny]

Then I planned my route home the next day to go by both NAPA (for the o-rings) and Ace (for hex head replacements).

As an aside, further reading on the topic of carb boot o-rings has led me to believe that the standard o-rings I got at NAPA might not last. Since I also bought non-stainless hex-heads (to save a few bucks, I guess) I'm just going to get the whole ring/stainless kit from our friend at Cycleorings.com.

 

[Guest]

Standard O-rings from NAPA would probably be made of nitrile rubber, which definitely can't take the heat from the heads. Get O-rings from Robert Barr, from McMaster-Carr, from Bike Bandit, Alpha Sports, or your local Suzuki dealer.

The original Phillips head screws for the intake boots are steel. When steel and aluminum touch, galvanic corrosion results. There won't be much of a chemical bond between the two metals - iron and aluminum just don't interact easily in this way. But corroded metal acts as an abrasive, resisting turning, and increasing the torque required to remove the bolt. The torque can easily get high enough to break the bolt or strip the head. Stainless steel fasteners don't corrode nearly as quickly as aluminum, and I think (but I'm not sure) that the galvanic corrosion of the aluminum won't be as fast, either. Anti-sieze compound can be used to lessen galvanic corrosion.

Aluminum expands more than steel when it gets hot. How much more it expands depends on the exact alloys used.

The indented paragraph is me dreaming about what happens. I might just be full of sh!t here.

If a metal donut is heated uniformly, all dimensions will increase, including the diameter of the hole. If the entire engine is heated slowly and uniformly, the ID of the threaded hole in the block will grow in diameter. But that isn't what matters. The outer diameter of the bolt threads isn't where the contact occurs between the bolt and the threaded hole. The contact comes on the flat surfaces of the threads. When a bolt is tightened, it stretches. When everything is made properly and is new, the bolt stretches somewhat uniformly, and becomes a linear spring. The flat parts of the threads press tightly against each other, and microscopic surface imperfections generate friction that adds to the torque from the stretching bolt. As the aluminum gets hotter, the separtion between the threads should increase faster than the separation between the steel threads, and the resistance to unscrewing the bolt should increase, which would be the opposite of what is experiences when two steel fasteners are heated.​