ambler Posted October 29, 2003 Posted October 29, 2003 I'm down to the crank. I have both Briggs manuals and it is not clear to me how to get the crank out. the bearing will not pass the cam gear. Do I have to pull the cam shaft and gear?
ambler Posted October 29, 2003 Author Posted October 29, 2003 I'm in a small engine class. One engine is 1974, the other is 1984. Both were in early 7016. The 1984 engine was smoking and running badly. The 1974 was not running but did turn over without much compression. Tearing them apart has been an adventure. 1984 incredibly dirty, valves fouled, probably overheated all the time with oil leaks. Good spark solid state. piston scored. 1974 good valves, no spark, broken ring, scored piston, little end pin squeaks when flexed. Neither engine has been bored before. Plan is to put solid state in 1974 with Bore oversize pistons and valve job. Rebuild carbs as well.
PatRarick Posted October 29, 2003 Posted October 29, 2003 The camshaft rides on a stationary shaft. I don't know if there is a trick to removing the crankshaft, but I have always removed the stationary shaft and moved the camshaft to the side when removing the crankshaft. Pat
ambler Posted October 29, 2003 Author Posted October 29, 2003 The old manual never directly says how to pop the crank out, but talks about pulling cam shaft and gear. new manual says that I should be able to position crank to clear cam gear. Then theres that big bearing in the way.
ambler Posted October 29, 2003 Author Posted October 29, 2003 Pat, I believe that's what the antique manual is implying. I think the new Lhead manual is wrong. I did move the cam gear a little. I'll have to fool around with it again. It implys that you get that gear to move forward out of the way. I want to see if the crank needs to be ground as well as valve and cylinder work.
HubbardRA Posted October 30, 2003 Posted October 30, 2003 Ambler, You don't need to remove the crank to check it for size (determine if it needs grinding). You do need to remove it if you are having the cylinder bored.
roma3112 Posted October 30, 2003 Posted October 30, 2003 Ambler When I rebuilt my 12hp mod 300421 (basically the same engine) I had to rotate the crank until there was just enough clearance between the cam and it. It is a tight fit and if i am not mistaken i had to push out/in on the crank and walk them (the crank and cam )simultaneously. If i get a chance to go to the shop today i will look through my briggs antique eng manual. good luck john
DaleC Posted October 30, 2003 Posted October 30, 2003 Be sure to inspect the crank carefully. All the way around the journal. A Crank can flat spot and/or score in one place. Use a mirror if you are not going to pull the Crank. Cranks can get "egg" shaped as well. You cannot tell that with out putting a Mic. on the Crank. I would at least take the rod and Crank to a Machine shop and let them Measure it for you. If they polish the crank, then have the Rod resized. It really is a simple job that any decient machine shop should be able to do.
ambler Posted October 30, 2003 Author Posted October 30, 2003 We have to pull the crank since we are going to bore. I'm going to mic the crank to see if it needs to be ground. While its in the machine shop valves will be ground and seated. This is a learning experience, but maybe two at once is a little much. I'll bring the block home and tinker with it, maybe clean some parts this weekend. I tried for a half hour to work the crank around the gear but it was late.
fuzy Posted October 31, 2003 Posted October 31, 2003 Yes if memory serves me right I believe you may need to pull the cam out to remove the crank. Just as Pat explained
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