GS450 Valve Cover Stuck

[VGplay]

I've been working on my recently acquired '82 GS450 and sent my carbs to Bill for rebuilding. Figured it would be a good opportunity to check my valve clearances since I haven't looked at them yet. Removed the bolts and it isn't budging. I don't think the cover has ever been off.

Before I start blindly trying different things, what have you guys done to break it free? I'd think a mallet could do the job, would I tap horizontally across the cover or find a spot to swing upward?

Also, looking at the fiche there are two versions of the '82 450 valve cover. One is labeled "-E.NO.162953" and the other "-E.NO.162952" and they have different part numbers for the gasket. Mine had 15 bolts so it looks like the 953 version is a match. But to verify, what does that number reference? It isn't the VIN and it doesn't seem to relate to the stamped serial number on the crankcase.

I appreciate the help!

 

[Guest]

if they have been on there since original they can be a pain to separate.....try gently with a mallet, maybe in combo with a piece of wood to get some upwards force going. I have heard some have luck with CAREFULLY inserting a sharp wood chisel in between the surfaces, right in the middle of the gasket and GENTLY tapping it in there to leverage them apart.....CAREFULLY, cause you really don't want to damage the mating surfaces... The hard part will be cleaning those surfaces up once you get it off....again, that sharp chisel can be useful, if used VERY CAREFULLY

 

[GregT]

Take the chrome end covers off. There are some nice ledges under there that you can tap on with a mallet and piece of wood.
If you have to get really dramatic, you can hit harder on the areas where the rubber half moons engage. They should have sealant on as standard so a little bruising shouldn't hurt.

 

[Guest]

Yep, what they said, don't use the bottom of the chrome end caps to lift it though. Tempting, but they're quite thin and would bend quite easily.

For your query on the number, that's the engine number. Part way through the '82 model year they changed from the 12 bolt to 15 bolt valve cover, the only difference I know that matters is knowing which valve cover gasket to order.

Good luck!

 

[Guest]

I had good luck with a stiff putty knife & a mallet, just had to work slowly around the parameters of the cover. A little pre-soak with WD40 helped soften things up.

 

[Steve]

Take the chrome end covers off.

That does not work with the 450 and 650 engines. Those engines reqire valve cover removal to be able to get to the screws that hold the caps on. You <might> be able to find a driver bit that is the perfect length to reach up to the screws, but I haven't found one yet. Fortunately, I don't have either of those bikes to work on.

.

 

[LAB3]

I used a thin screwdriver and tapped it in between the cover and head, once I got it started it separated pretty easy. As to the proper cover gasket, take a look at the side of the cover facing forward. One of the gaskets is symmetrical all the way around and one isn't, mine isn't. There's one bolt almost in the center of the front side of the cover that's offset from the others, I'm pretty sure that's the only spot where the two differ.

 

[VGplay]

Thanks for the help! A combination of everything got it off. I wet the perimeter with WD40 then used a sharp chisel and a mallet to set a score into the gasket in a couple of places. I tapped a flat and firm putty knife into the various scores until one started making progress along the seam. Once a large part of the knife was in I switched to a slightly thicker putty knife with a wedge-shaped edge and after just a couple taps it separated the cover from the head. Going to be tricky scraping the old gasket without letting bits fall into the engine, it is on there pretty good.

Which leads to another question. The service manual says to set the right-hand cam lobe pointed upright to check both cylinders. This works for the intake but on the exhaust just as I'm one ratchet tooth away from having it perfectly pointing up, the engine will jump ahead and settle with the lobe at a 2 o'clock position. After a couple tries to get it right I measured as it wanted to sit and both exhaust valves measured tight. Does that sound right or should I keep trying to get the lobe upright?

 

[Guest]

The centre line of the cam lobes need to be either perpendicular or parallel to the gasket surface to measure the clearances properly, and ensure neither lobe of the same cam is compressing a valve spring either.

There is a spot it can get tricky to get them to stay in position enough to measure, and I simply hold the socket driver where it needs to be with one hand while getting the feeler gauge in with the other.

 

[sacruickshank]

Thanks for the help! A combination of everything got it off. I wet the perimeter with WD40 then used a sharp chisel and a mallet to set a score into the gasket in a couple of places. I tapped a flat and firm putty knife into the various scores until one started making progress along the seam. Once a large part of the knife was in I switched to a slightly thicker putty knife with a wedge-shaped edge and after just a couple taps it separated the cover from the head. Going to be tricky scraping the old gasket without letting bits fall into the engine, it is on there pretty good.

Which leads to another question. The service manual says to set the right-hand cam lobe pointed upright to check both cylinders. This works for the intake but on the exhaust just as I'm one ratchet tooth away from having it perfectly pointing up, the engine will jump ahead and settle with the lobe at a 2 o'clock position. After a couple tries to get it right I measured as it wanted to sit and both exhaust valves measured tight. Does that sound right or should I keep trying to get the lobe upright?

Scraping petrified gasket material is a PAIN, probably my least favorite thing in resurrecting old bikes.

You can google all sorts of different techniques, but some key things to remember are:
1.) Scotchbrite pads are good in some cases but can cause grit to drop into the engine case. I would not use them in any situation where the grit is not controllable.
2. Fire is your friend. Once you've removed the easy stuff that does't require scraping, get a propane torch and burn the old gasket material. This will make the petrified gasket MUCH easier to get off.
3. I've used an assortment of scraping tools, from plastic razors up to metal blades. Anything metal should be used super carefully to avoid damaging the mating surface.
4. Scratched gasket surfaces aren't good, but the valve cover is probably the least sensitive surface. It's not under oil pressure, it's horizontal, and up high in the engine. Any possible leaks won't cause engine damage and are easily cleaned.

Enjoy