C113/123 engines

[Hairy Moose Knuckles]

I felt Jim made a very good point about this engine. Since I have my engine apart, I snapped a photo. I'm hoping he sees this. This could save people like me from ruining an engine by not knowing this tidbit of info.

Jim,
Thanks for all you do.

The rocker arm shaft is held in place on top of the head by 3 supports. The middle one is held by a nut (along with a very important flat washer) that threads onto a hollow stud. The stud is drilled on one end and the side. The hollow end goes down. Pressurized oil goes into the bottom end and out the side of the stud. It then flows through a passageway in the support to lubricate the rocker arm and the rest of the top end. You need to be gentle when tightening the nut as the stud is very easy to twist off. People have been known to install the stud bottom side up, or after loosing or twisting it off, replace it with a plain stud or a bolt. Any of these assembly errors will result in cutting off all lubrication of the top end. I would not try to remove the stud, as it is may twist off. After the engine is restarted, make sure there is oil flow to the top and take corrective action as needed.

[Dale Finch]

Good to know! Missed that post, so thanks for reposting!

Thanks, Jim!!

[2wheelsadam]

learned something today. Thank you

[John *.?-!.* cub owner]

I was working on a friends B414? and had the rocker arm shaft, it had bent a rod due to a suck valve (while I was mowing for him), and when I put it back together I had an uncomfortable feeling, and decided to fire it up before I put the valve cover on. Not the first time oil had been on my shed floor. You guessed it, no oil coming out of rocker shaft. I did not figure anyone in the area knew anything about that particular engine, so I Calle3d John at JP Tractor, one of the site sponsors. He told me to check the center support bolt, it was supposed to have a hole drilled up the center and another one ou the side. ?Sure e3nough, there was the funny looking bolt still in my cap with bolts not yet installed. Then I got oil on my floor, just like I should have on the first try.

[EdHarbur]

I'm having problems with sticking valves in a newly rebuilt C113. I looked through some posts on this and found one where Jim Becker wrote about "a very important flat washer" and nut holding down the middle rocker arm support. I don't have a washer on either of my C113s, and can't find it in my parts book. Any thoughts?

Jim Becker wrote:
The rocker arm shaft is held in place on top of the head by 3 supports. The middle one is held by a nut along with a very important flat washer that threads onto a hollow stud. The stud is drilled on one end and the side. The hollow end goes down. Pressurized oil goes into the bottom end and out the side of the stud. It then flows through a passageway in the support to lubricate the rocker arm and the rest of the top end. You need to be gentle when tightening the nut as the stud is very easy to twist off. People have been known to install the stud bottom side up, or after loosing or twisting it off, replace it with a plain stud or a bolt. Any of these assembly errors will result in cutting off all lubrication of the top end. I would not try to remove the stud, as it is may twist off. After the engine is restarted, make sure there is oil flow to the top and take corrective action as needed.

Thanks,

Ed

[Jim Becker]

I don't see any washer in the parts book either. Maybe I was remembering it wrong. Rather than be sure to use a flat washer, it was to NOT use a lock washer.

Related, I always thought there was enough space around the hollow stud that it didn't matter which way the side opening faced. Others have indicated that it needs to point towards the oil passage in the center bracket.

[EdHarbur]

Thanks for the quick reply. I'll rotate the stud just to be sure and use a washer.