81 GS550T Full Rebuild...In Ohio

[koolaid_kid]

Wire brush on a wired drill or a bench grinder (much easier) to remove the buildup. Be sure and wear eye protection.
Do you know how to lap valves?

[cowboyup3371]

Finally, did a little cleaning on the cases with Simple Green and water. I say a little as there's a lot of dirt, oil, and grime in places my brushes won't get to, even my bottle brush. So I'll do more later with better stuff.



I didn't see why that base gasket would have started leaking on me but I'll do what cleaning I can. When it's time to put new ones on, I'll just have to ensure I properly torque everything.

[cowboyup3371]

Wire brush on a wired drill or a bench grinder (much easier) to remove the buildup. Be sure and wear eye protection.
Do you know how to lap valves?

I've seen the procedure online and have had it explained but also have been told I didn't need to worry about it since I'm not replacing them. I'm nervous about doing it myself the first time though.

What's the truth?

[koolaid_kid]

You MUST lap the valves. It is not that difficult.

[loud et]

Already said, but agree, lapping valves is very easy, I dont think you could really mess up. O'Rielley, Autozone, Advanced, they all have the double ended suction cup tool, about 6 bucks and a twin tube pack or course and fine grit lapping compound.Maybe 5 bucks. It takes a lot of work to manually remove any material....its just a low material removal process to minimize any nicks, deposits or waves/irregularities and mate the surfaces a bit closer. Easy and good stuff.
+1 on the wire wheel in the drill also. I used it to remove the buildup on the valves, its hard as a rock, but so are the valves...you will not hurt them at all, but regardless I paid attention to not run the wheel on the shaft of the valve.
Nice to see the kids workin with ya

[Steve]

O'Rielley, Autozone, Advanced, they all have the double ended suction cup tool, about 6 bucks and a twin tube pack or course and fine grit lapping compound.Maybe 5 bucks.

I got one of those tools. BOTH ends are too big for GS850 valves, I would guess that his 550 valves are even smaller.

+1 on the wire wheel in the drill also.

I chuck the valve in the drill, then hold it up to the wire wheel in the bench grinder.

Besides cleaning the valve, it also offers the opportunity to verify that the head is not bent.

.

[Dogma]

You MUST lap the valves. It is not that difficult.

Eh? Why "MUST" if the valves and guides aren't changing and the seat's aren't being cut? Just to make sure of the seal while it's apart?

[loud et]

Quote Steve-
I got one of those tools. BOTH ends are too big for GS850 valves, I would guess that his 550 valves are even smaller.

**they had two sizes...I got the smaller combo one. I think it was maybe a 5/8 and 3/4 double ender. The 16 valve (exhaust I think) are quite small.

[Flyboy]

Good work Scott, +10000 on having the brood out here busy at it.
Like has been said, wire wheel the valves clean, can wire wheel the top of the pistons as well, but I would not wire wheel the sides of the pistons around the ring areas, unless you use a very soft brass brush.
The best thing for cleaning ring grooves is an old broken ring.......
Like Steve said, I put the valve to the wire wheel on the grinder, that way you can roll it in your fingers and check it is not bent.
Another way is to roll the valve on a flat surface, you will see if it is bent right away.
Truth is, Scott, you can do no harm lapping in the valves, I would not even consider putting them back without lapping them if I were that far in.
Easy peeezy, its just mindless work, the trick is to lap first with the coarse paste then with the fine paste, kinda like polishing.
You are looking for a uniform grey ring all the way around the valve and seat, without any marks or breaks, once you have that, put it all together.
It really does not take much.
The grey band is fresh metal on both the valve and seat, and means she is sealing up nice and tight.
Don't forget to pt just a drop of oil on the valve shaft so you have some lube between the valve shaft and guide when you are lapping.
Liners look ok to me, sure I can still see some cross hatch on number 1, just drag your nail and look for a ridge near the top, but I doubt you will find one, Jennifer has 3750000km on her and no ridge at all.

I also found out that all of my top and middle piston rings are well within specs (0.20mm to 0.25mm with service limit at 0.07mm) so that's $100 saved for other things.

Now either you dropped a decimal place there or you are going to have to explain that one to me...............as I read it, your gaps are way out of limit
Which, again, knowing these motors and your milage, I highly doubt, break out that vernier again, something don't look right with those numbers.

[cowboyup3371]

The specs for standard ring gap are between 0.10mm and 0.30mm per the Clymers with the service limit set at 0.07mm. So basically the gap should be a decent size but as it gets smaller than the rings don't work like they should. Let me go check my service manual real fast too.

EDIT: The Suzuki Service Manual says the same thing for ring gap

[Flyboy]

Ahhhh, that makes more sense Scott, service limit is 0.10 - 0.30 and you are at 0.20 to 0.25, puts you nicely in the middle.
As I read it, the spec at 0.07.
Carry on................

[loud et]

I was thinking back to when I ahd my engine apart and I did my valves and did use a wire wheel, but remembering now I did a little something extra that really helped.
I did a couple wraps of blue painters tape on the shaft end of the valve and lightly chucked it into my cordless drill. I held a peice of 220 grit and ran the drill and valve across the paper. Its easy to use your hand to confor the paper to the curves.It really gave it a good clean.
The main focus was originally the concave bottom of the valve, it REALLY helps the suction cup to stick when lapping, but seeing how good it worked I ran it up over the top too where the build up was.

[D-Mac]

As usual, lots of good advice on here.

To clean the valves, I prefer to take them in hand and put them to the wire wheel - turning slowly. I don't see anything wrong with using the drill, as long as you wrap the stems well. I learned cleaning as a 4-stage process: clean the margin, clean the area approaching the stem (although as others have said, do not let the wire touch the stem above where you have build-up), clean the sides, than then clean the face (bottom, where you attach the suction cup to lap them). Basically, just feel free to change your angle of attack as needed. Be careful that you don't have a valve go flying off on you! Also be VERY careful not to drop a valve.

I agree with the advice about lapping-in the valves. The service manual advises not to do it because of some magical Suzuki coating on the valves, but lapping won't take much off, and you won't need to wait 10,000 miles to get the benefits of an efficient engine that doesn't use oil, if you lap them now. Lapping will also clean up pitting on the valve seats, which seems really common in engines of this age.

If possible, I suggest you deglaze the cylinder, and definitely do it if you are replacing the piston rings. Ideally, you should check piston diameter (at the skirt), bore diameter (top/middle/bottom on x and y), ring end gap and side gap, and then calculate piston-cylinder wall clearance and make sure everything is in spec. That said, if you still have lots of cross-hatching on the cylinder walls, I bet you're in very good shape. I've checked four 550 engines ranging from 10,000-30,000 miles during my rebuild, and all were well within spec.

[cowboyup3371]

Thanks guys. Your advice is pretty timely as I started on cleaning up the valves tonight. I will have to buy a new wire brush for the drill but used the roloc style one I bought earlier this year.



What started like this on the intake valves:



Ended up like this after some time with the drill. I'm sure I have more to do before I even lap them. It's good to hear I can do the top of the valves as I'm a little nervous about messing them up.



Here is one of the exhaust valves before



and after



Then, I started to get a little lost on where I wanted to go since I really need parts before I can do much more with the engine. Yes, I'll go out to the base this weekend to dip covers in the wash tank but still.

So I played Mr Destructo with the lower steering bearing leaving this on the end of the stem near the lower triple tree. Is this still part of the bearing or is it a part of the stem? If it's a part of the bearing, how do I get it off?




After that, I grabbed a few things and went back inside.

First I repainted the kill switch thanks to Good Times. I think it will be okay though so we'll see when I get it all back together.



Then I tore into the clocks finding a few interesting items...







It was kinda neat to see the dead and decayed spider remains inside of them but yea, I don't want to see them again. Broke out the vacuum and away they went.

So, now off to go find Pete's and Rustybronco's thread about removing the odometer knob. I tried pulling on it but no luck. I'll also take some model cement to the rubber ring around the other clock casing since that's coming off.

[D-Mac]

Valves are looking better. There is still a little carbon you can get off (I think I have a few pics of what mine looked like before/after in my build thread). The look though.

As for the steering stem, you are making good progress, but you're not done yet. What you have left is the old inner bearing race, which must be removed so you can put on a new bearing. By far the best way to do this is to clamp the whole stem in a vice a few inches above the race (where it is tapered - somewhere in the middle part since it doesn't matter if it gets a little marred because the new bearing will easily go right over it).

After it's clamped, heat the race with a propane torch. Get it nice and hot. The race will expand a little, which can make all the difference in getting it off (especially if a little corrosion has formed between the race and the stem).

Immediately after heating, take a large drift/punch and and firmly hammer the race up off the stem (I also have some pics of what it looks like off in my thread). It's pretty easy because the race protrudes. I remember that it took a couple of cycles of heating and pounding to work mine off, and the race even chipped a little during the process. Work around it a little at a time so that it comes off evenly. Just be careful that your drift doesn't slip off and gouge the area immediately above the race. That part needs to stay smooth so the new race can "slide" on.

Installation: When you get a new set of bearings (I used allballs bearings) make sure you don't forget the washer under that lower bearing (you'll see it when you drive off that race). Installing a new lower bearing is easiest if you chill the lower stem in a freezer first (once you pack the bearing with stiff "green" high-impact grease first). Then use a pvc pipe that fits just over the stem but touches the new race close to the inside race to drive it down evenly over the stem. Sounds harder than it is.