leaking gaskets

[2BRacing]

The motor will never run as smoothly as it should with burnt valves. I suggest you ask in the "wanted" section for good second hand valves. Lap them in so they seal nicely on your seats and that will be a lot better than leaving burnt valves in. Replace the valve guide seals, hone the cylinders lightly to remove the glaze, and that motor should run well again for relatively little extra cost.

[bbjumper]

As long as you already have it torn down I think it would be a total waste of time and the money that you have already invested just to put it back together and hope for the best.

I recently completed just what your talking about, re cut the valves, honed the cylinder, new rings, gaskets and valve stem seals. with the top end healthy and maintained properly your scoot will last a LONG time, give you great service and a bunch of fun.

It cost me around $ 500.00 to get everything done including the machine shop work. No doubt a chunk of cash but now she runs like new and I won't need to do that again unless I screw up and don't take care of it.

This was worth it to me considering what I have now and what it would cost to replace it.

Cheers

[Hoggystyle]

ok so ive been reading around and want to clarify something before i start spending cash. my 3 exhaust valves are white, or mostly white, and i read that is not necessarily a bad thing and is common. i never had the chance to do a compression test before i took the head off, but the bike ran fairly smooth, even with the tight valves and decrepit carb o-rings. so does white on the valve mean it is burnt, or just ran very lean. i know these go hand in hand usually but im jsut making sure before i go drop another 100 bucks on parts. if i need to then of course i gotta make my girl happy

[2BRacing]

Lean combustion (higher heat) and too small or zero valve clearance will result in a "burnt" valve. However, just by looking at the colour on the valve is not an indicator that the valve is "burnt" or not.

A valve is "burnt" when the inner seat area that mates with the seat in the head (i.e. you cannot see that part without removing the valve from the head) has become so hot that it has melted or distorted the face area of the valve. When the clearance is too small or zero, the valve cannot close completely onto the seat and cool down enough from making contact with the valve seat, and the thin edge becomes melted or distorted.

Now that you have already removed the cylinder head, you should also remove the valves and inspect the seat area to determine if they have burnt or not. Clean the carbon off and use valve grinding paste and a wooden handle with rubber valve "sucker" to lap the valves onto the seats to obtain a good seal. Twirl the wooden handle backwards and forwards between your palms until there is a greyish circle of even width around the valve and seat. Clean all grinding paste off very well.

Use new valve guide oil seals when re-assembling.

[Hoggystyle]

is there a way to compress the valve springs to see the seat without pulling the valves? im not trying to bitch, but ive put around 2 grand into a 400 dollar bike already and havent been able to ride it for 6 months, so you can understand im getting anxious

[Nessism]

The valve seals must be replaced. Pull the valves, lap them after inspection, and put back together with fresh seals. Doing anything less at this point is foolish.

[mike_of_bbg]

Yes, please listen to Ed. Replace the valve stem seals (with OEM ones). They're cheap (Boulevard sells them for $4.31) and it won't take long. You'll also have to remove the keepers and springs to lap the valves anyway. Then you can put the valves in your carb dip to get them nice and clean. The only tools you need are a 6" C-clamp and a chunk of PVC (or I made a compressor from a block of wood instead).

Steve even made a video of the process:

http://members.dslextreme.com/users/bikecliff/images/valve_replacement.html

[Hoggystyle]

ok i watched the video, it looks very easy really, but what does the lapping process involve? i understand putting new seals in and setting it back in order, but what else do i need to do to get the valves right?

[mike_of_bbg]

The lapping process is just using a bit of lapping compound and a lapping tool (basically a stick with suction cups on the ends) to smooth the valve/seat interface. I'm sure you can find some YouTube videos on valve lapping. Compound + tool should cost about $10.

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Valve-Lapper-5--Lisle_22984552-P_N3491_T%7CGRP2083_____

http://shop.advanceautoparts.com/webapp/wcs/stores/servlet/product_Valve-Grinding-Compound-Permatex_7160108-P_N3565A_P%7CGRP2022___

[Hoggystyle]

ok ill look into that. i have an advance auto nearby so that should be easy. im looking right now for new seals, i see some on ebay, and saw some new aftermarket seals that raised the question: are old oem seals just as good as aftermarket as far quality as the rubber is old and hardened some?

[rwcfrank]

Are the OEM stem seals better than the Viton seals I see on Evilbay?

[bbjumper]

The OEM seals were good for the first thirty years on my 850 so that's what I used. Listen to Nessism, done right from the start will keep the cost down in the long run and every time you ride your scoot it will put a smile on your face.

[mike_of_bbg]

Were you to post an example link, someone might be able to say.

Are the OEM stem seals better than the Viton seals I see on Evilbay?

[Hoggystyle]

well i took heed to that advice and dismantled the head, i watched the video last night so i made a little pvc piece and had the whole thing stripped down and organized in about 45, which included cutting and buildign a plywood parts keeper for each valve.

all the valves look pretty good, no pitting, or chips out of the seat, and the beveled ring on the valve seat is smooth and not warped from what i can see, just dirty. i also pulled the seals and am going to "gunk" the head so i should be good to go when this is all back together.

here is what i saw on ebay http://www.ebay.com/itm/SUZUKI-GS550...9c594b&vxp=mtr

about $15 more than the oem ones on ebay. He does make a good point but im not sure how valid it is, becaue this is the first time i've ever torn an engine apart so i have no experience with oem vs aftermarket, though in most cases oem seems to be the way to go.

[Hoggystyle]

just in case this helps you rwcfrank, i bought my valve seals from Z1, which is a great site for GS parts. a few spins with my lapping tool cleaned up the exhaust valves , which werent really burnt, just black with carbon from hanging open so long. i was surprised they werent warped. it was way easier than i thought it would be, and using all purpose grease was priceless for putting the keepers back in. so if you were like me and didnt want to get in too deep becasue you were weary you could'nt do the job, Dont be! thanks for your help fellas