83 Engine Questions

[YellowstoneYeti]

Many, many years ago, I inherited an 83 Interstate from my father. I rode and enjoyed the bike for a couple of years. I then moved away and started a new life. The bike went into indoor storage where it has remained for the last 25 years. I'm at a point where I have the time to restore this bike.

I bought a new battery for it, but I got nothing when I tried to start it. I jumped straight to the starter and only got it to click. I pulled the starter and it seems to be OK. The motor appeared to be locked up. With nothing to lose, I sprayed PB blaster into the plug openings, hoping it would loosen up. When that didn't work, I pulled the heads off. The #4 cylinder has some rust in it. I used a 2x4 and 3# hammer and got the stuck piston loose pretty easily. I did a quick clean up with a razor blade to get the loose rust off. The pics show what the cylinder looks like. I think it looks worse than it feels. The rest of the cylinders are clean, smooth, and shiny. My question is: Is the motor salvageable? I read an article on this or another wing forum that recommended wet sanding with oil on the cylinder to polish it back up. Could I do a quick hone with the motor still in the bike without new rings? Are either of these techniques something I should contemplate?

My other question is what should I replace on the motor if it is salvageable? I already plan on new belts, lapping the valves, and rebuilding the carbs.

Any help would be much appreciated. I'd really like to get this bike on the road. Lots of sentimental value.

GW1.JPG

GW2.JPG

[Dlslick]

I often wonder about how some of the cylinders looked on bikes that I got unstuck and didn't open them up, then rode for years.
Might have looked worse than yours.

[CYBORG]

i would lower the piston in the bad cyl., and run a hone into it as far as possible, and see how well it cleans up. i have done that with engines, and have them work well. it will depend on how bad the rust is. from the pictures i would say you will wind up with a runner

[FLASH2002]

That picture of the rust is weird, when I took the heads of my 79 that was sitting in a barn for 20 years, one cylinder had rust but it was on the bottom not on the top.

[IndianaJohn]

Cyborg has it right. I ran into the same thing on my 76, and I did exactly as he described. I rebuilt my heads and did a compression test and I'm still a bit low on that cylinder, but I expect the numbers to come up once I start running it and get the rings freed up again. I'm planning on running some Seafoam in the oil for the first several miles to loosen them back up and clean out the crankcase.

[Gowing]

I know a 2 stroke is way diff bit my buffalo was stuck and it was
Just 1 cyl that had rust. I just cleaned up as best I could without any
Cyl honing and it is down a little on comp but runs just fine. So far.

[Greg]

That cylinder would have to clean up spotless before I invest time and money in that motor,any motor. The way I see it, if the cylinders are pitted so will the rings. Rings are mage from steel same as the cylinders. Too many good motor to be had ,cheap. IMO.

[Recycled Roadkill]

That cylinder would have to clean up spotless before I invest time and money in that motor,any motor. The way I see it, if the cylinders are pitted so will the rings. Rings are mage from steel same as the cylinders. Too many good motor to be had ,cheap. IMO.

My sentiments exactly. I would think there's pitting in the head too.

[Ericson38]

Does it crank over with the starter now? I would not run that piston up and down through there forcing the rings to do the cleaning and scaping....they will get impacted and want to stick in the ring lands.

Before you hone the cylinder, first try to hand clean it with 2000 wet or dry paper and WD-40, slowly, for a couple of hours. You don't want any metal power or otherwise down on the rings of the piston, so worry more about the bore and keep the piston at BDC. If it remains pitted (not just simply discolored), then it will always be a little low on compression on that jug and won't pull under load as smoothly as it could. If you do decide to lightly hone that one as a next step think about how deep the pits are, since you won't be able to get more than about .001 material removed that way. You area going to end up with a taper regardless at this point. First though, find something to put down the cylinder to keep the metal dust out of the ring lands.

How is the head gasket in this area? Was it still sealing, or is that where the water came from?

I would go for it though, you have nothing to loose with his engine, and if you have to buy another engine, you have a lot of spare parts from this one at your disposal.

What mileage? When I did my 83 standard at 68 k miles, there was no measurable ridge at the top of the cylinders, and plenty of hone crosshatching left. I bought mine at 50K miles 4 years ago from the original owner, and can certainly believe, based on the lack of cyl wear, that these engines can get 300K+ miles.

[YellowstoneYeti]

Thanks for all the replies. I've been working at it daily with tranny fluid and a razor blade. It gets a little better each time. I may have to resort to honing or wet sanding to get it to where I'd like. Would you recommend a ball hone? The motor only has 9K miles on it, so I'd like to stick with it if possible. I'm keeping an eye on ebay just in case I can't get this motor to where I want it.

[YellowstoneYeti]

Thanks for all the replies. I've been working at it daily with tranny fluid and a razor blade. It gets a little better each time. I may have to resort to honing or wet sanding to get it to where I'd like. Would you recommend a ball hone? The motor only has 9K miles on it, so I'd like to stick with it if possible. I'm keeping an eye on ebay just in case I can't get this motor to where I want it.

[Ericson38]

9K miles ! Great on you, plenty of material to work with (carefully).

On the hone you want the gentlelest process possible. You should really be able to (if you keep track of where you are working on the bore) get it cleaned up with handwork only. I haven't used a ball hone, all mine are replaceable stone wiper types (3 legged).

[IndianaJohn]

I used a borrowed ball hone when I did mine. I first hit the rust with some fine emery cloth and oil. Then after I got all the roughness smoothed out, I went over it with the ball hone. It came out feeling very smooth tho still a bit discolored. No more rust than I see in those pics, I would have no qualms about trying this method.

[YellowstoneYeti]

Well, I've been working on this for a few days whenever I get some spare time. It is definitely better than it was, but still has some pitting on the cylinder walls. I've taken it about as far as I want to by hand. Would a hone smooth out the pitting without having ring issues? I'm tempted to gamble on a gasket set and button it back up as is. I assume I may have lower compression and maybe a little smoking. Any other issues with putting it back together as is?

GW3.jpg

GW4.jpg

[fish]

I would run it!
I bet it will be just fine.
IF it smokes, then worry about it.