Valve Clearance

[bgsengine]

This is a neighbor's machine. The machine would start and run but after warm, it would not restart. He called me over and I tried to start it but it wouldn't. And it would kick back on the rope every full pulls.

Would have been very helpful from the start - First thing to check every time would be the flywheel key

Valve clearance would have been the next thing to check (for maintenance at least even if engine ran fine after fixing the key issue) I'll bet you have a sheared key.

[lefty]

BG strikes again....

So I need to pull this flywheel. But the holes for the puller bolts are not tapped. So I'm guessing I need to tap them? I was wondering about what size tap to use if anyone has an opinion. Too tight for me to get my caliper in there to get an idea of the hole size that exists. Also, the briggs flywheel puller I have is the wrong size. The bolts live way to far apart for this flywheel. I was thinking I would pick up one of those harmonic balancer puller sets from my local parts store. Is that a good idea?

[KE4AVB]

I surprise it even started being that much off.

If I remember correctly they use an 1/4-20 tap. I haven't seen any small walk behind engine in a couple years in the shop.

[lefty]

I surprise it even started being that much off.

I know right? I think It may have found its way over time. Each time it started and stopped it may have crept a little more maybe? I've heard it run for some time with the problem and it has gotten progressively worse over time.

[NO0C]

Glad you got to the bottom top of it Lefty!

Like Eugene, I'm amazed it ran at all.

[lefty]

I surprise it even started being that much off.

If I remember correctly they use an 1/4-20 tap. I haven't seen any small walk behind engine in a couple years in the shop.

These holes aren't very deep. The holes seemed to be a bit tapered as well, larger at the top. I have a 1/4 20 tap, which I think is plug or taper, I'm not completely sure. Would I need a bottoming tap for this? I'm not sure if I'm going to get enough thread in there for a pull.

As you may suspect, I don't have a lot of experience with tapping, which may explain my paranoia.

[KE4AVB]

Most of my Vermont American taps are plug style which help in getting the threading started straight. Once initially tapped you can if you wish used bottoming tap to finish up. I usually use both on blind holes as I like to as threads as I can especially if I am using a puller as I can really put some torque on those puller bolts. I had to start using grade 8 or better bolts on my harmonic balancer puller. I broke the arms on a two jaw 2 ton puller last year trying to pull a hub.

[lefty]

Awesome. Worked great.

So I got the flywheel off and it is aluminum. It appears as if when the key sheared, it damaged the wheel a bit. I slipped it over the shaft and it doesn't spin perfectly freely. Do I need to worry much about this? Should I deburr it? Or since it's aluminum on steel, will it just work itself out in the wash. It spins mostly around the shaft but then hangs up a bit in places when I turn it by hand. I wanted to have a picture here but photo bucket is busting my balls again. I'll upload when I can.

[lefty]

Image of the flywheel can be seen here.....I think.

https://screenshot.net/k0j50ty

[KE4AVB]

Uh that one can go either way more of judgement on your end if you to reuse it or not. I have reused them before without problems if not too bad. Maybe BGS has comment on this as he probably more than me as I see many of these smaller engines in the shop.

Note the list of the flywheel is $88.00. The flywheel key is mainly for alignment of the flywheel while your torquing it to specs. It the fiction of the taper that holds it in place during normal operations. Be careful not to over torque this flywheel as I have seen one split in two because of over torquing the retainer.