Dirty Valves

[NWDave]

Ok, so I pulled the carbs off so a friend could adjust the floats well anyway so I grabbed some shop towels to stuff in the intake so crab doesn't get in there and man it's like a magical carbon city on top of the valves.. my question is can I clean these without removing the head?  I know I could just keep pouring sea foam in the tank but I want results now.. so I guess I'm really asking how much work is involved with removing the head and installing new valves, and where to buy said valves.

[LimaXray]

Now I've never heard of doing this on the GS, but this is what a couple of my friends have done with their cars and it does work well.  Get a bottle of seafoam and put a 1/3 of it along with 10-15 gallons of gas in the gas tank (ok ok so in our case less then a 1/3)... next put a 1/3 in the crank case... for the rest of it, disconnect a vacuum line (like from the petcock and set the petcock to pri) and put it in the sea foam while the engine is running so it sucks it up... IIRC someone had to rev the engine a bit to keep it from stalling.  Once it's all gone, turn off the engine and let it sit for like 10 minutes, then fire it up and go for a ride.    Boy does it smoke like crazy.

Oh and change your oil after you ride for a half an hour or so!

edit: thinking about it, you may have to find a more clever way to feed the seafoam into the carbs because the petcock vacuum line would only feed one cylinder.  I think you can also take off the air box and try dumping the seafoam directly into the carbs some how.

[NWDave]

Been putting about half a bottle of seafoam in when I fill up.  Havn't put any in the crank case yet but I do need an oil change soon.. and as for feeding it into the carbs I have been trying to figure this one out as well

[The Buddha]

Maybe that is what is causing your carbon ...
Anyway water removes carbon ... spray water mist with motor hot and revving 3-4K into airbox ... and remember to ride it atleast 10 miles after you stop the water ...
Cool.
Srinath.

[NWDave]

Maybe that is what is causing your carbon ...

[LimaXray]

im under the impression putting seafoam in your fuel only cleans your fuel system and drys your fuel... you need to dump it in your intake to clean your valves... do a google search for sea foam

[GeeP]

A little coating of carbon, or oily piles of it around the intake valve stems?

If the latter, your valve seals are leaking and / or the valve guides are running loose.  Likely just valve seals.  Fix those and the carbon will go away.

As to all these "cleaning" additives, beware.  If it's a high mileage engine you'll likely loose all the sludge.  Your oil will look like it came out of a 2-stroke diesel, and lubricate about like dirty water.  Be ready to flush the engine several times over to remove the entrained solids.

If the carbon is causing a significant performance problem I suggest you do a top end.

[NWDave]

A little coating of carbon, or oily piles of it around the intake valve stems?

If the latter, your valve seals are leaking and / or the valve guides are running loose.  Likely just valve seals.  Fix those and the carbon will go away.

As to all these "cleaning" additives, beware.  If it's a high mileage engine you'll likely loose all the sludge.  Your oil will look like it came out of a 2-stroke diesel, and lubricate about like dirty water.  Be ready to flush the engine several times over to remove the entrained solids.

If the carbon is causing a significant performance problem I suggest you do a top end.

It's nasty looking, I'd take a picture but I don't have a camera.  Again where can I buy new valves on the internet?

[Turd Ferguson]

I heart GeeP.

-Turd.

[GeeP]

It's nasty looking, I'd take a picture but I don't have a camera.  Again where can I buy new valves on the internet?

No need to replace the valves if they're within specification.  If they're not in specification you can buy them from bikebandit.com or your local Suzuki dealer.

What you need is a bench grinder with a fine wire wheel, or a small wire hand brush.  For your first time out I suggest the hand brush.  Remove the valves and wire brush all the crap off.   Don't overbrush with a bench grinder in an attempt to remove the oxide discoloration and get back to shiny metal.  Also, don't brush the valve stem.  The only areas of the valve that need to be spotless are the sealing faces and the stem.

While you have the valves out, inspect the valve guides carefully for wear.  This is generally done in the field by measuring valve face runout in various locations spaced diametrically around the valve guide.    Be sure not to mix the valves between cylinders, as this can accelerate wear.

The Clymer's manual will describe all of the above in detail, including pictures where necessary.   

I heart GeeP.

Jesus...  How many closet lovers do I have on this site?   

[Mandres]

I'm really asking how much work is involved with removing the head and installing new valves, and where to buy said valves.

There is enough work involved to make it a pain in the rear end.  It's not terribly difficult, but it takes time, space and money.  Here are some things to keep in mind if you're going to tear into the top end:

1.  You'll need a new headgasket, head o-rings, stem seals and probably basegasket. 

2.  It's difficult to remove the head without disturbing the gasket between the cylinder and the block.  If this gasket is disturbed you'll need to remove the cylinder to replace it, which means you should also hone the cylinder and possibly fit new piston rings. 

3.  To get the valves out of the head you'll need a valve spring compressor.  They are expensive to buy but you might be able to borrow one or make your own (Details in the FAQ section by Dgyver). 

4.  To properly measure the components for wear / warpage you'll need a set of feeler gauges, a small micrometer, a 6"+ dial caliper, a set of hole gauges and a dial gauge with base.  Whether you do all the checks is up to you, I skipped a couple of them on my rebuild, but if you go by the book you'll need all the tools.

5.  The best thing I found for removing the carbon deposits is Easy-Off Oven Cleaner, the "odor-free", aluminum-safe variety in the blue can. 

6.  Once the valves are out and the head is cleaned up check the valve guides very carefully for cracks.  They are cheap to replace and if one breaks you're going to have big problems.

-M

[NWDave]

Screw it, I'm just gonna pour cleaner in the carbs and let the next owner worry about it.