Broken bolt in block under throttle body adapter - what now ?

My question is why, why are you removing sump bolts if you do not want to remove the sump?

The bolts in your photo look clean, makes me wonder why they would be stuck so bad that they break. Did a previous owner or someone working on the bike use high strength loctite on them or over torque them so they were close to failure (probably not going to happen with steel bolts in a aluminium thread).

If loctite was used, at least the stumps will stay put, otherwise they could back out themselves under engine vibration, since the squeeze is gone with the bolt head removed.

Will be difficult to get the stumps out without removing the sump. If you don't get an oil leak then you will be ok riding it around until such time the sump has to come off, then they will be easier removed.
 
My question is why, why are you removing sump bolts if you do not want to remove the sump?

The bolts in your photo look clean, makes me wonder why they would be stuck so bad that they break. Did a previous owner or someone working on the bike use high strength loctite on them or over torque them so they were close to failure (probably not going to happen with steel bolts in a aluminium thread).

If loctite was used, at least the stumps will stay put, otherwise they could back out themselves under engine vibration, since the squeeze is gone with the bolt head removed.

Will be difficult to get the stumps out without removing the sump. If you don't get an oil leak then you will be ok riding it around until such time the sump has to come off, then they will be easier removed.

I noticed a bit of oil after sitting awhile and tried the bolt. It was loose. So I tried to tighten it, lightly! and it twisted off. Most all were loose, not enough to the eye, but using a wrench they were very easy to turn in. I used a torque wrench at 12 Nm and snapped another one. The rest were able to get to 12 Nm but I was very wary on some of them.
The one good one I took out just to see what I need to get to replace them. I see no sign of loctite.

As you stated, I suppose the engine vibration backed them off a bit, but not enough to spot just by looking.

I bought me a couple of M6-25 bolts at the local Ace Hardware and will try one of those *when* I get the stubs out. The OEM's are M6-28, but the only size they had longer than the 25 was a 30.

Any way thanks for all of the input! I'll try the simple stuff first and take a good look to see if I can tell if the stubs will be longer than the engine block if the sump is removed.
I have all the bolts and a gasket tucked in my shopping cart at 2WheelPros in case I have to go that far. One bolt is different than the other 20, I see from the schematics.

I DO NOT want to remove the sump for some reason. Maybe just a bit much beyond my comfort level.

I'm not in too big a hurry. Gonna be out of town visiting my boy in NM this weekend. Might try the mini screwdriver, pencil eraser stuff tomorrow, though.

Then @Joesmoe's trick with a reverse drill bit. Might try a wood dowel in there first to see if it will grab enough to back it out. If that won't then I'll drill through the dowel to make a center guide for the drill.

Knock on wood.
 
I noticed a bit of oil after sitting awhile and tried the bolt. It was loose. So I tried to tighten it, lightly! and it twisted off. Most all were loose, not enough to the eye, but using a wrench they were very easy to turn in. I used a torque wrench at 12 Nm and snapped another one. The rest were able to get to 12 Nm but I was very wary on some of them.
The one good one I took out just to see what I need to get to replace them. I see no sign of loctite.

As you stated, I suppose the engine vibration backed them off a bit, but not enough to spot just by looking.

I bought me a couple of M6-25 bolts at the local Ace Hardware and will try one of those *when* I get the stubs out. The OEM's are M6-28, but the only size they had longer than the 25 was a 30.

Any way thanks for all of the input! I'll try the simple stuff first and take a good look to see if I can tell if the stubs will be longer than the engine block if the sump is removed.
I have all the bolts and a gasket tucked in my shopping cart at 2WheelPros in case I have to go that far. One bolt is different than the other 20, I see from the schematics.

I DO NOT want to remove the sump for some reason. Maybe just a bit much beyond my comfort level.

I'm not in too big a hurry. Gonna be out of town visiting my boy in NM this weekend. Might try the mini screwdriver, pencil eraser stuff tomorrow, though.

Then @Joesmoe's trick with a reverse drill bit. Might try a wood dowel in there first to see if it will grab enough to back it out. If that won't then I'll drill through the dowel to make a center guide for the drill.

Knock on wood.

When you can, just drop the sump and fix the broken bolts.

Also, when I reinstalled my sump, I backed off the recommended torque due to a)threading into aluminum and b) no need for 100 in lbs on this. It’s just a sealing surface. I noticed this when I started to torque them, and just didn’t like that much torque, so I lowered mine to 50-70 in lbs.

And as you found out, these bolts are not structural grade, so they break easily.
 
I noticed a bit of oil after sitting awhile and tried the bolt. It was loose. So I tried to tighten it, lightly! and it twisted off. Most all were loose, not enough to the eye, but using a wrench they were very easy to turn in. I used a torque wrench at 12 Nm and snapped another one. The rest were able to get to 12 Nm but I was very wary on some of them.
The one good one I took out just to see what I need to get to replace them. I see no sign of loctite.

As you stated, I suppose the engine vibration backed them off a bit, but not enough to spot just by looking.

I bought me a couple of M6-25 bolts at the local Ace Hardware and will try one of those *when* I get the stubs out. The OEM's are M6-28, but the only size they had longer than the 25 was a 30.

Any way thanks for all of the input! I'll try the simple stuff first and take a good look to see if I can tell if the stubs will be longer than the engine block if the sump is removed.
I have all the bolts and a gasket tucked in my shopping cart at 2WheelPros in case I have to go that far. One bolt is different than the other 20, I see from the schematics.

I DO NOT want to remove the sump for some reason. Maybe just a bit much beyond my comfort level.

I'm not in too big a hurry. Gonna be out of town visiting my boy in NM this weekend. Might try the mini screwdriver, pencil eraser stuff tomorrow, though.

Then @Joesmoe's trick with a reverse drill bit. Might try a wood dowel in there first to see if it will grab enough to back it out. If that won't then I'll drill through the dowel to make a center guide for the drill.

Knock on wood.
where abouts in N.M.?
 
Use a small socket wench and and firm them up. You don't have to try and drive them through the block, but just a comfortable tight.

That is true of a few bolts on this thing. When I replaced my fuel filter on my Touring I tried the recommended torque and snapped off two of the bolts on the underside of the tank. After that I disregarded the torque settings and snugged them down with a box wrench and called it good. It is working so there is that. ;)

bob
 
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