brchad
Member
- Joined
- Oct 26, 2017
- Threads
- 3
- Messages
- 34
ENGINE:
Briggs & Stratton, 17.5 HP
31C707 3346 G6
Code: 110224ZB 23882
Just as an introduction, I'm 70 and have been working on small engines since I was 10 years old. My employment background was sales and maintenance for two different pump companies in the Petro-Chem market .... specialty engineered centrifugal pumps for hazardous liquids (canned motor pumps and magnetic drive pumps.) With all that said.... I'm totally baffled by this problem with a Briggs & Stratton one cylinder engine! I've run out of ideas!
I've had the typical problem that's so prevalent on the web: the ridiculous compression release system and was fortunate enough to run across your instructions for setting the valves at 1/4" past TDC compression stroke. That saved me from replacing the third intake push rod and I began checking valves .... sometimes twice per season.
In spite of all my maintenance efforts, I had used the mower, shut it down.... went to restart it a week later and got the "lock up" when starting with a good battery. I tried setting and checking the valves about 10 times before I took the engine off and opened the sump. Sure enough.... there was those pieces of the compression release mechanism in the bottom of the case.
I purchased a new camshaft and installed it per factory manual.... lining up timing marks, etc. When I mounted it on the mower, I tried turning it CW by hand. It turned several revolutions and then FROZE (CLANK) in one place. I pulled the sump back off and saw that the timing marks (Crankshaft and Camshaft) were aligned .... piston about half way down. Just jammed. I stripped the engine down to the short block (not removing connecting rod, piston, counterweights, etc.) including the head. Took the head off, tappets out, rods out, etc. (New oil all over everything by the way.) I inspected the Crankshaft timing gear... I see no visible signs of wear. (I have a new one on order anyway.)
This is NOT the compression release problem.... where the engine hits the compression stoke and it's difficult to turn. When I say FROZE .... I mean it's JAMMED.... and will not turn forward period. The only way to unlock it, is to use channel-lock the shaft and turn it backwards. Then, if it's moved CW again .... it locks up.
Here's a weird piece of information: If I put the Camshaft in a random position (out of time in other words) the engine turns CW freely and doesn't gall up. Very strange.
Any suggestions, ideas, wild guesses, etc. would be great.
Thanks
Briggs & Stratton, 17.5 HP
31C707 3346 G6
Code: 110224ZB 23882
Just as an introduction, I'm 70 and have been working on small engines since I was 10 years old. My employment background was sales and maintenance for two different pump companies in the Petro-Chem market .... specialty engineered centrifugal pumps for hazardous liquids (canned motor pumps and magnetic drive pumps.) With all that said.... I'm totally baffled by this problem with a Briggs & Stratton one cylinder engine! I've run out of ideas!
I've had the typical problem that's so prevalent on the web: the ridiculous compression release system and was fortunate enough to run across your instructions for setting the valves at 1/4" past TDC compression stroke. That saved me from replacing the third intake push rod and I began checking valves .... sometimes twice per season.
In spite of all my maintenance efforts, I had used the mower, shut it down.... went to restart it a week later and got the "lock up" when starting with a good battery. I tried setting and checking the valves about 10 times before I took the engine off and opened the sump. Sure enough.... there was those pieces of the compression release mechanism in the bottom of the case.
I purchased a new camshaft and installed it per factory manual.... lining up timing marks, etc. When I mounted it on the mower, I tried turning it CW by hand. It turned several revolutions and then FROZE (CLANK) in one place. I pulled the sump back off and saw that the timing marks (Crankshaft and Camshaft) were aligned .... piston about half way down. Just jammed. I stripped the engine down to the short block (not removing connecting rod, piston, counterweights, etc.) including the head. Took the head off, tappets out, rods out, etc. (New oil all over everything by the way.) I inspected the Crankshaft timing gear... I see no visible signs of wear. (I have a new one on order anyway.)
This is NOT the compression release problem.... where the engine hits the compression stoke and it's difficult to turn. When I say FROZE .... I mean it's JAMMED.... and will not turn forward period. The only way to unlock it, is to use channel-lock the shaft and turn it backwards. Then, if it's moved CW again .... it locks up.
Here's a weird piece of information: If I put the Camshaft in a random position (out of time in other words) the engine turns CW freely and doesn't gall up. Very strange.
Any suggestions, ideas, wild guesses, etc. would be great.
Thanks