How Cheap is to Cheap

[Plyscamp]

I have been working on small engines for about 55 years now and spent 20 of those years in manufacturing and service of The Green Machine string trimmers, blowers and chainsaws. My son brought in a Craftsman / Briggs Sratton 34 CC 4 stroke powered string trimmer to look at. It belongs to one of our very good clients. With a little diagnoses I determined the cam timing was off, leaving the intake valve open at top dead center. I pulled the cam cover for inspection and believe it or not found a PLASTIC CAMSHAFT. Yes folks it even has plastic lobes. We used to laugh when I was younger that eventually we would have rubber camshafts so we would get more lift as the RPM's increased. But I never thought I would see a plastic cam lobe in a production engine. Even better the engins is so cheap that most of the internal components (includind the camshaft) are not available as replacement parts. This particular engine had skipped 3 teeth on the plastic cam gear that is driven by a worm gear on the steel crankshaft. Whats next from these brain childs, Glass filled nylon rods ? OOPS better not give them any ideas.

 

[stumper63]

I would say that is way too cheap. Guess I better investigate before I buy my next string trimmer...

Stumper63

 

[MacLaren]

No doubt. Thanks to the OP for the 411. 55 years experience is awesome.
However, if I buy a new trimmer it will be a Pro Husqvarna model. I believe /hope I would be safe there.......

 

[dingeryote]

I have been working on small engines for about 55 years now and spent 20 of those years in manufacturing and service of The Green Machine string trimmers, blowers and chainsaws. My son brought in a Craftsman / Briggs Sratton 34 CC 4 stroke powered string trimmer to look at. It belongs to one of our very good clients. With a little diagnoses I determined the cam timing was off, leaving the intake valve open at top dead center. I pulled the cam cover for inspection and believe it or not found a PLASTIC CAMSHAFT. Yes folks it even has plastic lobes. We used to laugh when I was younger that eventually we would have rubber camshafts so we would get more lift as the RPM's increased. But I never thought I would see a plastic cam lobe in a production engine. Even better the engins is so cheap that most of the internal components (includind the camshaft) are not available as replacement parts. This particular engine had skipped 3 teeth on the plastic cam gear that is driven by a worm gear on the steel crankshaft. Whats next from these brain childs, Glass filled nylon rods ? OOPS better not give them any ideas.

Briggs went to doing stupid things with all their 4cycles several years back, and overall have gone well past the point of too cheap.
First time I saw the plastic camshaft on a Vanguard motor, was the last time I worked on one, or bought one.

What is the point? Fix the cam and then what? Some other POS component takes a crap?
I have better things to do than repair Playskool toys that should be making me money instead of costing me.

Stay safe!
Dingeryote

 

[morgaj1]

Doesn't surprise me. I used to think that these half crankshaft 2 stroke motors were the worst. Now, I hear that the Kohler Courage series motors have plastic camshafts too. Then, I look at my 1969 Sears XL-12 riding mower with a 10hp Tecumseh motor. I wish I knew how many hours that thing has on it. I long for the days of steel, cast iron and side-valves.