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Discussion Starter · #21 ·
So, I replaced the Valve stem seal last night by hand, I used a magnet and a piece of PVC pipe inserted the PVC pipe into the hole for the exhaust valve spring and inserted the telescoping magnet in the center of the pipe, and using my hand I grabbed onto the pipe pushed it down releasing the valve keepers and used the magnet to remove them. I changed out the seal and now I am on to putting the new piston in and putting it all back together.

One thing I was wondering is if anyone happens to have a service manual for my bike, also if anyone knows what the bore specs are supposed to be for the piston jug so I can see if my original piston jug is still within spec I'd appreciate it.
 

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Discussion Starter · #23 ·
Here is one for an 1982. Pretty well the same motor.
tmas
Oh okay thank you, I did something stupid while assembling the top end and now I get barely above 30 PSI on the compression, I ripped the corner of the paper gasket that goes between the main part of the engine and the rear of the piston jug and air is leaking out, so now I've gotta order a new Gasket and tear it back apart and then put it back together again and see what my compression is then, because I changed out the piston and piston jug and all the gaskets except the Cylinder Head gaskets for the Rocker arm cover and the cam cover.
 

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Discussion Starter · #24 ·
Well for some reason I have a oil leak from the Cylinder Head cover on the right side of the engine the odd looking plate that is right next to the spark plug hole, the plate the long bolt goes through to hold the cam cover on. Anyways I used a brand new gasket and it's leaking oil right there, also how long does it take until I can do a compression test that will give me accurate readings I heard I have to wait for the rings to set or something. I did a compression test after putting it together and I get about 60 PSI, so is it due to where the oil is leaking or something else. Any help would be appreciated.
 

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I would investigate that oil leak as soon as possible, and not run the bike until you do. Make sure you have the gasket oriented correctly on the plate, so as not to impede the flow of oil through the cam to lubricate the head.
 

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Discussion Starter · #26 ·
I would investigate that oil leak as soon as possible, and not run the bike until you do. Make sure you have the gasket oriented correctly on the plate, so as not to impede the flow of oil through the cam to lubricate the head.
I'm pretty certain I have the gasket oriented correctly, but I will double check just to make sure. If that doesn't fix it, what else would you suggest, RTV Silicone gasket maker perhaps?
 

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No, RTV silicone gasket stuff doesn't belong on these little engines, too many horror stories of the excess globs falling into oil passages and severely restricting (if not cutting off) oil flow.
 

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Discussion Starter · #28 ·
No, RTV silicone gasket stuff doesn't belong on these little engines, too many horror stories of the excess globs falling into oil passages and severely restricting (if not cutting off) oil flow.
Well that is something I'm hoping to avoid because I personally don't like the stuff, so I thought I'd ask for an opinion on the stuff. What about if I used rubber gasket material and used the gasket as a stencil?
 

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You're actually better off using a new gasket, and make sure the mounting bolts and the cam sprocket cover bolt are snug in place.

If a new gasket isn't an option, you could you a thin coat of ThreeBond 1184 on the old gasket, after cleaning it with contact cleaner and pat drying it with a paper towel before applying the the 1184.
 

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Discussion Starter · #30 ·
You're actually better off using a new gasket, and make sure the mounting bolts and the cam sprocket cover bolt are snug in place.

If a new gasket isn't an option, you could you a thin coat of ThreeBond 1184 on the old gasket, after cleaning it with contact cleaner and pat drying it with a paper towel before applying the the 1184.
Is it possible for a gasket to be too thin, also how do you remove the remnants of a old gasket, because ive been using a brass wire brush and it doesn't get everything but it seems to be pretty flat.
 

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I use a single-edge razor blade to get underneath the old gasket, and slowly work the razor along, keeping it as parallel to the surface as possible, to prevent gouges.
 

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Discussion Starter · #32 ·
I use a single-edge razor blade to get underneath the old gasket, and slowly work the razor along, keeping it as parallel to the surface as possible, to prevent gouges.
Oh okay, I did that to get the main parts of the gasket off very carefully, maybe I didn't get the surface as clean as it should be, I would think though with the pressure applied by the bolts there would be no way it could leak past the gasket so I'll definitely check the orientation of the gasket and the mating surfaces. Thank you for answering my questions and helping me out.
 

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No a 48 dollar head won't even make a good boat anchor. Stay away from no name Amazon and ebay engine parts.
This is interesting to me. I have a ct70, ZB50, lifan 125 and a skyteam 125. all 4 have cheap big valve E22 heads and run flawless. The old stock honda heads don't have bearings on the cam. Once the honda head wears it's trash
 
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