Open up one of the larger Briggs & Stratton lawn mower engines and you'll see that they have now opted for NO bearings whatsoever, just aluminum rods on steel crank. Also running an aluminum block. Always wondered whether this was just a built in engine replacement scam. Doug Rupert Simcoe Ontario
-----Original Message----- From: krnet-bounces+drupert=sympatico...@mylist.net [mailto:krnet-bounces+drupert=sympatico...@mylist.net] On Behalf Of Brian Kraut Sent: Sunday, April 04, 2004 9:30 AM To: Orma Robbins; KRnet Subject: RE: KR> Engine Bearing The material that they make the bearings out of is not that hard. Apparently, using the aluminum case as the bearing with an oversize hub works to some degree. The biggest problem is that you have to change the whole crankcase when the bearing surface wears out. I am certainly not suggesting that anyone do this on their engine. I remembered hearing about an engine at one time that was made to use aluminum beraings so I did a search and found that it is common. I coppied this from an article I found on bearings: BEARING MATERIALS At the original equipment level, the use of aluminum main and rod bearings is growing for a variety of reasons. One is that aluminum bearings are less expensive to manufacturer than bimetal or trimetal copper/lead bearings. Switching to aluminum also gets rid of lead, which is an environmental concern for manufacturers. But there are many other reasons, too. "Federal-Mogul provides both copper/lead and aluminum bearings. But perceptions are changing with respect to aluminum versus copper/lead," said Federal-Mogul's Ron Thompson. "Most of the original equipment manufacturers are going to aluminum bearings, as are a growing number of rebuilders in the aftermarket. Many people are switching to aluminum because it provides improved durability and better control over tolerances. The whole article is here in case anyone is interrested: http://members.aol.com/carleyware/library/ar797.htm Brian Kraut Engineering Alternatives, Inc. www.engalt.com -----Original Message----- From: krnet-boun...@mylist.net [mailto:krnet-boun...@mylist.net]On Behalf Of Orma Robbins Sent: Sunday, April 04, 2004 9:05 AM To: KRnet Subject: Re: KR> Engine Bearing "for even suggesting" Morning John; Like I said, having two open cases side by side was interesting. I lifted out my crank and sat it inside the type 2 case, and sat the other crank still with the bearing installed into my type 4 case and the fit was nearly exact. For me that varified that the builder intended to omit that bearing. It looks like the prop hub was made to be the exact size that the case is. With the Force One bearing the case is opened to accept the bearing. Tomorrow I will go to the airport and get my mic and measure the prop hub diameter and compair it to the diameter of the #4 crank bearing on the type 2 crank. Orma L. Robbins Southfield MI 19 Years flying KR-2 N110LR http://www.aviation-mechanics.com _______________________________________ to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html _______________________________________ to UNsubscribe from KRnet, send a message to krnet-le...@mylist.net please see other KRnet info at http://www.krnet.org/info.html
