In need of serious help breaking a bolt loose. Help!

Factual Questions
1

I have a big problem. I am trying to change the oil filter on my bike (82 Honda GL500 - Twin). There is an aluminum oil filter housing that goes on the front of the engine. There is also a bolt that holds this on. The bolt is about 3-4" long, goes right through the top centre of the filter and threads into the block. This is what holds the oil filter housing on. I cannot get this bolt loose. It has a 12mm head and I am totally rounding the edges of the bolt and/or chipping the edges off it. I have resorted to vice grips and all that does is round the edges off as well, but they do get a better bite than the wrench (and the grips are on TIGHT).

I have gotten the engine up to operating temp and it still doesn’t help. I have also struck the head of it several times with a hammer in an effort to bust loose. No joy.

Folks, I really need a hand here. Any ideas? I am getting desperate here.

2

If (IF!) the bolt is replaceable once the nut is off you could get a Dremel moto-tool ( 30- 60)and abrasive cutting disk (at least one comes it) and simply slice the nut head off and after removing the cover, grab the bolt stem with a pair of pliers and thread it out. If nut is not accessible to cut off or bolt cannot be backed out once nut head is removed you could try the following. If there is enough metal in the nuthead (and angle is workable) you could drill a small hole just under the head of the nut and then use a steel pin of some kind to get additional leverage for removal.

Have you tried spraying WD-40 etc on the nut area prior to attempting removal? I would imagine doing it cold would be better than doing it warm unless you would possible heat up just the nut head with a soldering iron or something and not the bolt as well but this would be difficult as they are physically coupled.

3

There is no nut. The bolt threads right into the block through the oil filter housing. I guess the “nut” side is already in oil… engine oil.

Thanks though. Anything else?

4

I had a similar problem with the oil drain plug on a car of mine. The plug was probably considerably larger than your bolt head, and I had more room to work under the car, but the oil in this car hadn’t been changed throughout the winter and the plug had rusted.

I tried sockets (the rusted plug just rounded over), channel-locks (good grip on the nut, but couldn’t apply enough torque while holding them tight), vise-grips (similar), and finally a pipe wrench. A pipe wrench is built to grip smooth pipes, and is constructed in such a way that once it gets a bite, it tightens as you turn. The plug loosened two seconds after I put the pipe wrench to it, and I bought a replacement plug for a dollar.

If you have enough clearance for a pipe wrench (they’re usually large and heavy), give it a try.

5

Been there, done that, 1983 Honda CBX550, similar housing.

Those bolts are easily replaceable but your biggest risk is in snapping the bolt leaving just the thread in the engine block.

I can’t remember exactly, but on your machine the exhausts get in the way don’t they ? If so it would make your life easier to take it off, though from the sound of it these may be a pain to remove if they are corroded in place.

Next thing you are not going to like, you really should not have attempted to remove it with vice-grips, this makes things less than easy.

Get your hands on an impact/percussion driver, fit the correct size socket on the bolt and give it a right old whallop, this does usually does the trick.

Try heating up the bolt head and see it that separates it from the filter housing.

Failing that you may need to gently warm up the block with a torch but this might be risky as you’d only be heating a small area, it would be better to run the engine and get the whole thing warm and then heat up the casing around the filter.

Having been so brutal with the bolt I’d suggest you replace it anyway.

You could go completely vandalistic by destroying the housing,(but make sure you can lay hands on another first) its quite brittle alloy and comes apart easily enough, this would give you a whole lot more bolt shaft to grab.

This will probably solve your problem as it is usually the bolt head that corrodes onto the filter housing, what goes into the engine block is usually ok but…

Total desparation means doing this plus saw just the top of the bolt off and drilling down it(the bolt is hollow).
If you do this make sure the diameter of the drill is smaller than the thread but not by much and retap the thread.

6

Hmmm. I might give that a try. The only problem I can forsee with that is that the head of the bolt is only about, say, 1/4 of an inch high. Might be tough to get a bite… but that is too good of an idea to abandon. Now, if I only had a pipe wrench… :frowning:

7

casdave, I hit reply to that other one just as your post came in. You are thinking the same wavelength as me here though, you are talking the same style of housing. The exhaust really aren’t that badly in the way. I just have to be careful not to grab them after I run it to get the engine warm!

I was not aware of an impact driver for hex heads like that. I will have to go do a bit of shopping. Thanks! I will be sure to let you know.

BTW - Where do you think its hanging up? On the threads or the bolt --> filter housing? If it’s not the threads, why is it not coming out? Wouldn’t you think the filter housing would just spin up/out with the bolt?

8

The filter housing will not spin out with the bolt because it has a small lug that engages into a projecting part on the engine casing,(I’m now wondering if you can bust the tangs off to allow it to rotate with the bolt, somehow I doubt it) the head is likely seized onto the filter housing, though it is possible it seized into the casing.

9

Did you try turning it the other way? Of course, if you got it off before you’d know which way it turns. Sometimes they put them on so they go the other way.

10

My Yamaha Radian had the same problem. What I ended up doing was tapping a six-sided ASE socket onto the rounded bolt head. Between the tapping on the bolt and the tighter-fitting socket, I was able to get the bolt free with no problem.

Another option would be to get some canned compressed air and chill the bolt down. (Hold the can upside down and spray the hell out of the bolt.) This would cause the bolt to shrink slightly and might make it easier to remove. Don’t try this if the engine is hot, and be careful when trying to remove the bolt as it may be a little more likely to shear off.

The impact wrench idea is good, too. Pick up a cheap one at your local Big Lots store for about $7.

Good luck!

11

The bolt may be treated with locktite to prevent vibration from loosening it.You’ll have to heat it with a torch…carefully…to get the locktite to breakdown.
Buy a tap and die set and some “easy outs” while you are out.If the head is too rounded off to get a socket on it,drill a hole and use an “easy out”.
Good luck

12

No, its not loctited or anything. I am the one who put it together last. Oh well. I gave up for tonight. Guy gave me a bit of an idea though. Tommorow I will bring home a can of freeze-spray that will cool it to about -100 or so… then I will try to break it loose. Either it will come out or I will spin the head off.

I appreciate the ideas folks. I am a pretty acomplished back yard “grease monkey” and believe me, I’ve run accross seized bolts before, but nothing like this. I’ve rebuilt several engines and do all of my mechanical work myself. Uggh… beaten by a 6 or 8mm bolt.

Well, tommorow I am going to call Honda, order in replacement parts. Maybe get a tap the same size too. That way if the freeze spray doesn’t work I won’t totally destroy that mutha until I am ready to replace it.

Thanks again. Uggh!

13

Can you get a pipe wrench onto the shoulder of the bolt, or are the fins on the filter housing in the way? If you can use one there, the added diameter will give you a little more torque, and the wrench will get a better purchase than it would on the flats of the bolt. You could use Vise-Grips here too, but a pipe wrench would get a better grip.

If you can’t do the above, you might try hammering a six-point 7/16" socket onto the bolt. The socket should fit and the hammering will help break the bolt loose. Personally, I gave up on impact drivers after a year of being a mechanic; they never really seemed work as well as hammering directly on a socket or bit, then driving the hammer/bit off.

If all fails, crush the filter housing apart with a c-clamp and buy another from a salvage.

As an aside, what brand of sockets are you using?

14

If you’ve totally given up on the bolt because it’s rounded off, you might as well drill it and use the easy outs. That’s not too difficult. Another thing you could try is taking the cutting disk on a dremel and cutting a nice deep slot in the head of the bolt, turning it into a flathead screw. This has worked for me, but it takes patience to get the inside of the slot nice and square so the turning doesn’t cause the screwdriver blade to lift out. But I like any excuse I can find to use my dremel. :smiley: