Craftsman Yard Vacuum

[l008com]

I have a maybe 15 year old craftsman yard vacuum. Long story short, its plastic timing gear melted, so I had to pop the engine off and replace it with a new one, that was metal. When I opened the motor, I was expecting a melted camshaft. But the camshaft looked perfect and the gear that spins it clearly was not.

So I did the repair, fixed some other parts on the machine, and put it back together. (and made a youtube video for the whole job).
Today was the first real use of the machine since the repair. I did some test running previously, but this was the first actual use sucking up leaves.

There were two things I noticed that I am curious about. Note, this is all just "informational". The machine is absolutely running good enough and I have zero intention of opening it back up again!

First, it is VERY hard to pull. Probably the hardest to pull engine I've ever had. This got me thinking today, is it possible the compression release function on the camshaft was also damaged from likely overheating, and I just didn't notice? And so the machine is stuck with "normal" compression? I am able to start it with one pull, but it takes a hell of a pull.

Second, when you shut this thing off, it spins for a LONG time. Do these machines not have an engine brake like lawnmowers to? Maybe because their impeller is fully enclosed? Or should it have an engine brake, and mine may just be broken?

I actually have a picture of the camshaft and timing gear it turns out. I don't know exactly how the compression mechanism works. But it appears to have it and I'm pretty sure its not working. What do you think? (again, this is just for curiosity, I am definitely NOT fixing it)

 

[ILENGINE]

Engine brake only used on push mowers. And the reason for the hard pulling and the same reason for the long spindown is because vacuum shredders have a very heavy impellor. The impellor has to be heavy to both resist the wear and tear of grinding up sticks and leaves but to also create enough momemtum to keep the engine spinning under heavy load. That heavy impellor both makes the engine hard to pull initially because you are trying to get that heavy flywheel spinning but also that heavy flywheel takes longer to stop.