Question-
Thanks for the answer Eric. The rings have no bevels and there is no dots on either side. I believe they are cast iron. Should the cool bore cylinder be cross-hatched like a normal cast iron cylinder? The machine shop cross hatched mine, but the final product is definately rougher than any cast iron cylinders I've had bored, honed and cross-hatched. I don't think the machine shop I used bores very many aluminum cylinders. Should I smooth the cylinder walls a bit with aluminum polish and a buffing wheel? Any advise you can give would be MUCH appreciated. Daryl ------------------------
Followup To
Question -
Hello Eric, I've got a B&S engine, model 252707, type 0145-01, and the date code starts with 79 (can't remember the rest). It has an aluminum bore. It was smoking bad, so I tore it down and had it bored 0.20 over. I ordered a kit off eBay that included 0.20 over piston, rings, valves, and gaskets. Do I HAVE to use chrome rings on an aluminum bore? B&S only offers chrome rings in the std size. (found out later) The two compression rings in my kit are solid black. I installed new piston and rings last night, and even with lots of motor oil lubrication, there seems to be excessive friction between piston and bore. (takes lots of muscle to push piston in and out). Ive check my ring end gaps and everything checks out (0.015). When I pulled the piston out, there was shiny aluminum already rubbing off on the rings. How vital is it that I use a chrome piston and rings? I really appreciate your advise. Daryl
Answer -
Did the rings come with directions on how to install them? They may have beveled or flat edges on the rings that need to be installed correctly.
Chrome rings aren't really necessary. Briggs offers them in a standard bore if you do not bore and replace the piston. The chrome rings are supposed to burn less oil but are not normally recommended.
Let me know about the ring directions.
Eric
AnswerWas your orginal piston black or chrome plated?
The top two rings should be beveled or have a rectangle groove cut in them. The bevel/cut maybe on the inside of the ring. Take another look...the small bevel/cut can be difficult to see.
Let me know about the piston and rings.
Eric
