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Just took my head off - what do you reckon?

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RodW Rod White
St Margarets-at-Cliffe, Kent, UK   GBR
Looks like there was a bit of a leak but the cylinder doesn't look too bad. I was expecting some scoring but it just looks like normal wear and tear. The piston rings look reasonable too.

DO you think it's best to just rebore or do I put a liner in there? I want to keep things original so I don't really want to change the cc by a straight re-bore and just leave it like that - do you get what I mean?

Thanks.

Rod

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OlympiaScooterCompany Avatar
OlympiaScooterCompany Silver Member Matthew Gatlin
Olympia, WA, USA   USA
Hello Rod,
Was the motor in running condition before removing the cyl head? Did you check and see if the head warped? I would clean it up and try adjusting the bolt pattern when putting it back on.



Matthew Gatlin
Olympia Scooter Company
Cell: 503.954.4043
Email: sales@olympiascootercompany.com
Website: www.olympiascootercompany.com

RodW Rod White
St Margarets-at-Cliffe, Kent, UK   GBR
I dont know if it was running or not to be honest. I want to get it checked to see if it's warped or not and recondition it. I don't know where to get that done. I know I'll need some parts.

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OlympiaScooterCompany Silver Member Matthew Gatlin
Olympia, WA, USA   USA
If you have a piece of glass you can check it on there to see if it is warped.



Matthew Gatlin
Olympia Scooter Company
Cell: 503.954.4043
Email: sales@olympiascootercompany.com
Website: www.olympiascootercompany.com

RodW Rod White
St Margarets-at-Cliffe, Kent, UK   GBR
do you put some paint or something on the glass or the head and rub it on top to see if there are any blind spots, or do you mean just lie it on there?

OlympiaScooterCompany Avatar
OlympiaScooterCompany Silver Member Matthew Gatlin
Olympia, WA, USA   USA
Hello Rod, did you have any success with the cylinder head? My guess is the previous owner did not tighten down the cylinder head in a star pattern causing it to warp. If the cylinder head ends up being warped, replace it. You will spend more time and money trying to correct the issue than it's worth.



Matthew Gatlin
Olympia Scooter Company
Cell: 503.954.4043
Email: sales@olympiascootercompany.com
Website: www.olympiascootercompany.com

RodW Rod White
St Margarets-at-Cliffe, Kent, UK   GBR
Hi,

I haven't checked it. I'm still trying to strip the engine down before I work out what I need to buy. How do you check if it's warped then?

Rod

OlympiaScooterCompany Avatar
OlympiaScooterCompany Silver Member Matthew Gatlin
Olympia, WA, USA   USA
use a piece of glass to check if it's warped...



Matthew Gatlin
Olympia Scooter Company
Cell: 503.954.4043
Email: sales@olympiascootercompany.com
Website: www.olympiascootercompany.com

RodW Rod White
St Margarets-at-Cliffe, Kent, UK   GBR
How?

enigmas Avatar
enigmas Vince Stok
Melbourne, Victoria, Australia   AUS
Hi Rod...if you're still around surfacing the alloy head is a simple straight forward task.
Materials, Equipment & Method.
1. A flat glass pane or a machined steel flat bench top.
If you're using glass the flat side windows of an old classic car is suitable. Old house windows aren't as the glass is not flat but often have a wavy surface.
2. A sheet of emery paper of 120 grit should be suitable.
3. Masking tape. (Tape the emery paper to the glass pane)
4. Degreaser (clean the cyl head prior to surfacing it)
5. Simply rub the cylinder head on the flat surface in a back and forth manner.
Rotate it 45° every now and then so that you don't end up sanding it on an angle.
Clean the emory paper and head of debris as you proceed. Check the head mating surface every now and then for smoothness and flatness. Ensure any or all tangential score marks on the surface are removed.

That's it.
Change to a finer abrasive paper for a smoother finished mating surface. You'll note though as the surfacing/sanding progresses the paper will become less abrasive.

Cyl & Piston.
If the ring lands are in good shape on the piston, the piston is not heavily scored on its skirts and the bore does not have a significant wear lip, simply have the bore lightly honed (use a ball hone...the other type 'abrasive stone hone' will remove too much material and bell mouth the cyl) then fit new rings.

http://crosstools.com.au/honing---flex-hone----cylinder-hone.html



Edited 4 time(s). Last edit at 2018-09-10 05:31 PM by enigmas.

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