Ring replacement

Kent

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I have a Subaru EX-17 that I want to replace the rings on. Subaru parts site shows them for $45. On Amazon I see rings for the model for $15. The Amazon description says they are Genuine Taiwan quality. I assume the rings sold by Subaru are OEM.

Do you believe there is a big difference in quality?

Also both sites offer 0.25mm oversize as well as STD. Do I need to go with oversize if all I am doing is cleaning up (light honing) the barrel??
 

JTSpeedDemon

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Link to the Amazon one? I've had a lot of experience hunting down OEM parts, and I prefer them since aftermarket ones tend to be inaccurately sized. But yeah, there are certain "warning signs" that can help tell whether something's really OEM or if the listing is misleading. I could tell with a link.
 

Kent

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See if these links work........thanks

https://www.amazon.com/Piston-Rings...baru+277-23511-17+rings&qid=1598035546&sr=8-1

https://www.lawnmowerpros.com/detail.asp?id=282-23521-H7

The lawnmowerpros link says manufactured by Subaru......

Maybe you know this.....To get the piston out and replace the rings and clean up the barrel can you do it by working around the big gear (cam gear I think) that's between you and the bottom of the push rod when you pull the cover off? I haven't opened the case yet. I should be able to figure that out when I do so. I was just wondering because I don't know how complicated things may get if I have to take that gear loose.

Drawings in the service manual seem to look like there might be room to reach around the gear and remove the bolts holding the rod in place.

http://subarupower.com/wp-content/u...x17-ex21-ex27-sp170-sp210-ex21efi-service.pdf
 

JTSpeedDemon

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That Amazon one is misleading. It's not made by Subaru, don't buy it. Especially with something as important as piston rings.
The one from lawnmowerpros looks great, actually not too bad pricewise(at least for a Subaru! :roflol:)

I haven't worked on a Subaru OHC before, but if you plan to hone the bore, I would remove absolutely everything from the crankcase to eliminate chances of metal shavings causing mass destruction and wear. On flatheads I can remove the con rod and piston with the cam in, although it's less than optimal. I suspect it's even tighter on Hondas and Subarus. I would open it up being prepared to pull absolutely everything apart.
 

anickode

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That Amazon one is misleading. It's not made by Subaru, don't buy it. Especially with something as important as piston rings.
The one from lawnmowerpros looks great, actually not too bad pricewise(at least for a Subaru! :roflol:)

I haven't worked on a Subaru OHC before, but if you plan to hone the bore, I would remove absolutely everything from the crankcase to eliminate chances of metal shavings causing mass destruction and wear. On flatheads I can remove the con rod and piston with the cam in, although it's less than optimal. I suspect it's even tighter on Hondas and Subarus. I would open it up being prepared to pull absolutely everything apart.

Subaru OHC is just that... An OHC. Overhead cam. Timing chain must be removed to take the head off anyway.

You can't hone the bore with the piston in, so that pretty much leaves you with just the crankshaft in the block. You could (and I would recommend) removing the crankshaft, however you can stuff a damp towel in the block to catch any of the honing dust.

Honing should never take more than a thousandth or two off. 5 thou in a last ditch effort. Really though it should only be just enough to restore the crosshatching. If you need more than that, it needs to be bored. So oversize rings should not be a factor.
 

Kent

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I took the timing chain loose, removed the head and opened the case up. It wasn't very complicated at all. The cylinder bore didn't look bad at all. I didn't pull the crank out as it was easy to work around and like I said the bore looks pretty good. The bore just showed some, I guess you would call them "rub marks" at both ends where the piston ends its strokes. I cleaned the bore up by hand with some 220 paper. I hope that's alright. I really didn't change the bore at all but I did catch the small bit of dust on rags. It really was so little dust you could hardly see any.

So anyway I ordered the head gasket and rings but the rings are on back order everywhere I checked. I'm just hoping they do a run of these rings so I can finish this up. It has been fun so far.

Do any of you members know if the upgrade kits with exhaust, carb and air cleaner made for all the clones etc. would be likely to fit the Subaru Robin EX-17 ??? Thanks for any input.
 
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