Stuck valve cover, how to break free?

[madadam]

Hi all,

I am trying to check valve clearances on my '82 GS400T (tscc), like the manual says I should around now (~32k km). I've run into a bit of a stopper just taking the thing apart - the valve cover is stuck on. The gasket is probably original and is now rock solid... I tried wedging a plastic scraper in there, but it just broke apart. I'm very hesitant to try to pry it apart with anything harder than plastic, for fear of damaging the metal surfaces.

I've searched the forum and found lots of recommendations on how to get stuck bits of gasket off, but none on separating stuck parts. I had the same problem before with the clutch cover, but got that off by banging it with a rubber mallet. I'm not sure this approach will work here, since the valve cover seems more fragile and I'm worried about cracking it. I've tried spraying the seam with WD-40, carb cleaner, and brake cleaner, all to no avail. I've been a bit sparing with the chemicals, to avoid getting them in places they shouldn't get.

It probably doesn't help that it's well below freezing and I'm trying to work on it while it's wedged into my cramped shed.

Anyone have any ideas on where to go from here?


Cheers,
Adam

 

[Dogma]

I was going to suggest the rubber mallet...

Fill the crankcase with propane and light it? Maybe that's a bad idea.

Maybe pry gently on the bridge part of the cover with the mallet's handle?

 

[Pete Logan]

It probably doesn't help that it's well below freezing and I'm trying to work on it while it's wedged into my cramped shed.

Anyone have any ideas on where to go from here?


Cheers,
Adam

Below freezing doesn't help with brittle metal.

If it were me, I would wait for a better day, and then put a piece of wood against it sideways, and give it a couple light taps with a heavy steel hammer.

Using a rubber hammer doesn't really help, it just compresses the hammer. You need something to shift it without breaking the metal.

 

[madadam]

Below freezing doesn't help with brittle metal.

If it were me, I would wait for a better day, and then put a piece of wood against it sideways, and give it a couple light taps with a heavy steel hammer.

Using a rubber hammer doesn't really help, it just compresses the hammer. You need something to shift it without breaking the metal.

Thanks for the replies.

It's hard to wait for a better day since that won't come until spring... and trying to blow it off is maybe a bit extreme

I've been trying the wood and hammer thing, but was hitting upwards in the corners. I'll try shearing it sideways next.

Thanks
Adam

 

[SqDancerLynn1]

I would double check & make sure all of the bolt are removed

 

[KRISTI'SGS550]

Adam,
I have a little story that might aide in you discovering a remedy for your situation. Last week I bought a can of degreaser from Wally's World. One of those generic ones with the blue and black label. I got home and sprayed the stuff all over the engine. My engine is quite dirty and the reason for buying the cleaner was to get the grease and grim off. Well the degreaser I bought foams up really good, thus making it stay on the metal for a while. I think this is how it works. I let the foam stay a while and came back to clean the parts. Later that day I decided I had nothing to do so I would check my valve clearance. I took out my screws, the hose, and lifted the valve cover. Low and behold, the gasket (which I just installed last year) was completely soaked. The degreaser ate through the gasket. It didn't ruin it, just soaked it really well.

Maybe if you try degreaser, the kind that foams, around the gasket it will soak it up and allow the gasket to seperate.

Another thought. Could it be glue and not a gasket?

Cory

 

[Pete Logan]

I've been trying the wood and hammer thing, but was hitting upwards in the corners. I'll try shearing it sideways next.

Thanks
Adam

Always sideways, but sharp, light blows. You're not trying to remove the thing in one go, just dislodge it a little.

 

[Guest]

I would double check & make sure all of the bolt are removed

+1! Check, esp. toward the front of the engine...I had this happen once...fortunately I didn't go medieval on it when the mallet failed.
Tony.

 

[earlfor]

There are 14 (fourteen) bolts that need to be removed. How many do you have out?

Earl

 

[Suzuki_Don]

Below freezing doesn't help with brittle metal.

If it were me, I would wait for a better day, and then put a piece of wood against it sideways, and give it a couple light taps with a heavy steel hammer.

Using a rubber hammer doesn't really help, it just compresses the hammer. You need something to shift it without breaking the metal.

Be careful tapping it sideways. If there are locating dowells holding it to the head damage can be caused.

 

[madadam]

Adam,
I have a little story that might aide in you discovering a remedy for your situation. Last week I bought a can of degreaser from Wally's World. One of those generic ones with the blue and black label. I got home and sprayed the stuff all over the engine. My engine is quite dirty and the reason for buying the cleaner was to get the grease and grim off. Well the degreaser I bought foams up really good, thus making it stay on the metal for a while. I think this is how it works. I let the foam stay a while and came back to clean the parts. Later that day I decided I had nothing to do so I would check my valve clearance. I took out my screws, the hose, and lifted the valve cover. Low and behold, the gasket (which I just installed last year) was completely soaked. The degreaser ate through the gasket. It didn't ruin it, just soaked it really well.

Maybe if you try degreaser, the kind that foams, around the gasket it will soak it up and allow the gasket to seperate.

Another thought. Could it be glue and not a gasket?

Cory

Interesting. I'll pick up a can and give it a shot. I was hoping the carb or brake cleaner would do the same, but had no luck with those.

It's a gasket all right. I've managed to chip a small piece off with a plastic scraper before it broke.

Thanks,
Adam

 

[madadam]

+1! Check, esp. toward the front of the engine...I had this happen once...fortunately I didn't go medieval on it when the mallet failed.
Tony.

I keep thinking the same thing and have gone over it many times... that's not to say there's no way I have missed one (or two). I'll check again for sure though.

Adam

 

[madadam]

Always sideways, but sharp, light blows. You're not trying to remove the thing in one go, just dislodge it a little.

For sure. I've been tapping a few times, then trying to lift it off (just by hand, not prying it).

I'm beginning to question whether it's worth checking the clearances after all.

 

[Guest]

regards the freezing temperatures - why not warm the engine up before using the mallet
i would also leave the cover unbolted, the engine vibrations should help - and if you see an oil leak somewhere - thats the spot where you want to pry the cover off

 

[Junkie]

regards the freezing temperatures - why not warm the engine up before using the mallet
i would also leave the cover unbolted, the engine vibrations should help - and if you see an oil leak somewhere - thats the spot where you want to pry the cover off

a warning related to this: if you don't get it fully warmed up, make sure to let the bike sit upright - not just on the sidestand - for a minute or so after you've run it. i had let mine idle for maybe 15s right before removing mine, and dumped a ton of oil down the side.

 

[madadam]

regards the freezing temperatures - why not warm the engine up before using the mallet
i would also leave the cover unbolted, the engine vibrations should help - and if you see an oil leak somewhere - thats the spot where you want to pry the cover off

That's not a bad idea... but it will take a bit of work. Besides the reassembly, my bike doesn't really like to start when it's this cold, let alone sitting for several months already. But, nothing else is working so I'll give this a try.

I'll be sure to use the centrestand afterwards as well, thanks for that tip.

Thanks,
Adam

 

[lurch12_2000]

For sure. I've been tapping a few times, then trying to lift it off (just by hand, not prying it).

I'm beginning to question whether it's worth checking the clearances after all.

Depends on the last time valves were checked by you and how far off they were. I wouldn't try to start it to warm it, but if you want, you can using a hair dryer to break a slight ice seal which might be holding you up.

I think at this point you should consider a good quality 2" putty knife to gently tap between the valve cover and the gasket. If you get a little marring it would be on the cover side so you could touch it up when it is off.
I am talking about tapping it in a couple of places before trying to twist the knife to break the seal.
I very lightly coated my new gasket with grease to keep it in place when putting the cover back in place and hopefully to keep it from sticking (like your's is now) for the next time you do adjustments. Even with the paper gasket I only "2 fingered" the bolts when tightening. Do not over torque!
Check the 8 cam hold down bolts when you're in there as a couple of mine were slightly loose. Again do not over torque these!

 

[Smokinapankake]

I've heard (but don't know how true it is) that torqueing a bolt, then retorqueing at some later time (like next time you check valves), and doing this every time you have the cover off, will stretch the bolts until eventually they snap. I'd be particularly careful with the cam bearing journal bolts. How much would that suck to break one of those off? I've never done it but I'm sure some others here have.

This, of course, if you get that cover off in the first place.....

 

[Pete Logan]

I've heard (but don't know how true it is) that torqueing a bolt, then retorqueing at some later time (like next time you check valves), and doing this every time you have the cover off, will stretch the bolts until eventually they snap.

OK - the actual measure of how you tighten a bolt is stretch.

For every bolt, of every strength, there is a correct measure of stretch to make it work right. You need a dialer to measure it, but you can't always get one in there, so we use an approximation.

Torque is an approximation of stretch. That is, it is assumed that for the same bolt, the same amount of twisting power will produce the same degree of stretch.

Bolts once stretched will retain some degree of stretch when they are released.

So your assumption is in principle correct. If you keep stretching them, then sooner or later they will break.

That said, if the manufacturer's torque recommendations (ie: stretch) are well within the capabilities of the bolt, perhaps the bolt can tolerate being stretched that much for quite a number of times without a problem.

Personally, I prefer the equation:-

Cost of Bolt - Cost of Buggering everything up = NoBrainer :-D

Of course, I reuse bolts, nuts, and anything else I can.

But only if there are no stress issues involved.

I also use cereal packets to make gaskets out of.

Not head gaskets, though :-D

It's horses for courses, but if you are at all concerned about the bolt, buy a new one (or 20).

 

[Junkie]

That depends on how much you're stretching it. If you're staying in the zone of elastic deformation, it'll be fine forever (or damn near). If you're deforming it plastically, you'll have a limited lifetime. I'm guessing the torque specs are low enough that you aren't getting that close to plastic deformation.