angellonewolf
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View attachment 225400 getting there taking ages
You could use some rougher emery rather than start off with something super fine. I’d have started at 400 grit, but being gentle just to take off any major imperfections, then move onto something finer.
There’s a gasket on it anyway so it doesn’t need to be a mirror finish. And it’s not exactly a race engine.
Be careful you are keeping pressure smooth and flat, as it’s easy to lean too hard and find you are actually making it cut too much at one side. Moving in a figure of 8 is the ‘correct’ way to do it.
I'm getting near lapping the valves any one got a positive idea of the gaps for the valves ?
If you grind the valves check the valve clearances afterwards adjusted by grinding the end of the stem 8 thou inlet and 13 thou exhaust comes to mind but please check in a manual.
^^^^
And I've got 2 compression testers and every time I use them they give different readings
Quite possibly as the engine has automatic compression release to aid starting !!
snooker ball under the valve (piston side) and use adjustable and some brute force to push the spring guide down?' often find that happens if someone bodges a makeshift spring compressor, err, so I'mtold.'
We rebuilt the head of a GS125 years ago and for a valve spring compressor used a snooker ball and an adjustable spanner
Prize for the first correct answer has to how we did it.....
Not seeing anything wrong with that engine at all. Exhaust valve looks a bit mucky so a good clean will sort out any issues with either valve jamming open. Grinding the valve seats is an easy job but getting them out has its own issues. Wear safety goggles because if you lose control of the spring compressor you could take an eye out (or it might end up wedged at the back of your skull). I often find that happens if someone bodges a makeshift spring compressor, err, so I'm told.
Grinding is easy but all too easy to go too far. It might not even need it (unlikely) clean them thoroughly and look for signs of wear. If the valve is worn out, no amount of grinding will help, if it is only slightly worn, take as little off as possible while checking by eye for a continuous band of fine paste or ideally, clean it regularly and check with a transfer blue (or a Sharpie).
Bore looks fine, you could give it a quick de-glaze as has been suggested. No reason to expect a warped head unless 1. there is some evidence for it or 2. the engine is known for it.
So long as you are careful not to damage anything taking it apart, merely taking it apart, cleaning it and reassembling will do wonders. You might even find a blocked port or breather that will also have affected performance. Check for blockages at the air filter and the exhaust system but mechanically, it is as simple as that and if you don't change too much by excessive grinding, you shouldn't have to worry about valve timing etc.
Carburation is a whole new level of pain and a lot of outdoorsy petrol engines suffer from fuel blockages/restriction and especially in those tiny holes that everyone says don't poke a stick at but secretly everyone does.
got a Honda but no bag for it and been looking for ages none aboutor u could get a used honda and end all the probs except for the mounting....
early B+ Strattons were great.....
B&S engines are good, but let down by the carb side.
All the ones I have scraped have been solid inside. but the fuel tank and carb fail.
Yes they can be rebuilt, but when I was needing a working engine it was cheaper to get a working one.