How's she goin'? This was a worthwhile dissection if you ask me. You had an engine that was not running correct and then by stripping down the engine you were able to determine what the possible cause was. This will help with another engine with similar symptoms. This is how we learn and I thank you for going the extra mile on this one!! Take 'er easy!!
Great video Bruce as allways.That engine is for the spares pilelol.I have had an old Atco dropped off for repair but the cylinder is scored.Another one for the graveyard.All the best to you all.
I still remember those valve specs from so many years ago: intake: .005-.007", exhaust: .009-.011". Good point indeed, forgot all about that damn flywheel key. Funny how this thing sounded rich and lean
@@BrucesShop I know I heard you say that you replaced the carb, the tank as well? Seems like the valve adjustment is OK, compression seems normal, flywheel key OK. hmmmmm
OK, got excited when I saw those cheesy plastic cam gears, thought that might be the issue. The piston does look strange, but who know what they are made of these days... You mentioned the ring gap looked OK, I was thinking perhaps someone ran the engine for awhile with no air filter, or didn't oil the foam properly, letting the dirty air wear down the cylinder. When did Briggs start using the internal governor instead of the old vane style? Guess I have been out of the game for awhile....
Hi Bruce....lawn mowers being strange beasts is hitting the nail right on the head!! I like the air compressor trick to add air! I love these little engines almost as much as I love the Quantums....too bad it didn't end up like the Pastor's Craftsman.
Interesting stuff, never seen a blackened piston before. I thought it was rings when you couldn’t find a fault anywhere else. Got shown a picture today of a utterly smashed piston from the engine of a fishing boat. Engine was recently rebuilt, whoever rebuilt it got the timing wrong.
Bruce, I once had a quantum that was all coked up on the head and had a real bad ridge on the cylinder also. The person had the wrong plug with wrong heat range and wrong gap. Was incomplete burn and caused the bad running and the coking. Cleaned it up, new plug and it ran fine.
Listening to that engine running bruce my 1st job (after changing the d&g) would of been checking the air intake tube for cracks or damage, everytime i service 1 of these old briggs classics i always tighten the 2 bolts holding the tube on as they tend to vibrate loose
You are right to look at the intake tube. If the intake tube was cracked or loose it would be running lean by letting in more air. I did checked it to see if it was plugged. Sorry I did not show that. I thank you for joining in.
Very thorough inspection. I think if I would have gone that deep into an engine I would have rebuilt it with a new brand new piston and rings possibly new valves. I also would also seat the valves to be sure of a perfect seal. It would probably be as good as new. If that didn't fix it I would get a brand new carburetor and diaphragm. It would be extremely hard for me to take an engine down to the crank and not put new life into it. Couldn't do it.
@@BrucesShop true hmmmm maybe try a new set of piston rings. That is probably what I would try and if the cylinder was lightly damaged I would maybe try my luck with a cylinder hone to smooth it out best I could. I have seen it work beautifully with two strokes. Not the same as new but close to it.
Time to ask Santa to bring you a leak down tester while your in Mexico. This helps pinpoint internal engine issues without teardown. It is almost like someone opened the get in the carb and it is flooding with too much fuel and it got better when you provided more air to balance it out.
I would bet on the piston having a pinhole(or a dozen). The other thing I was thinking about was the little ridge you mentioned at the top of the cylinder... Maybe the entire bore has changed over the years and the rings aren't as tight as they could be?
Wow. Love the trick of using shop air to force it to lean out. This old dog learned a new trick today, thanks!
Right it was rich so i thought "more air!!!"
me too mate
How's she goin'? This was a worthwhile dissection if you ask me. You had an engine that was not running correct and then by stripping down the engine you were able to determine what the possible cause was. This will help with another engine with similar symptoms. This is how we learn and I thank you for going the extra mile on this one!! Take 'er easy!!
Thanks again sir.
Great video Bruce as allways.That engine is for the spares pilelol.I have had an old Atco dropped off for repair but the cylinder is scored.Another one for the graveyard.All the best to you all.
Thanks for sharing. Yes this one is one and done.
Ever since I been watching your videos I learned a lot keep up the good work Bruce
Thanks, will do!
I still remember those valve specs from so many years ago: intake: .005-.007", exhaust: .009-.011". Good point indeed, forgot all about that damn flywheel key. Funny how this thing sounded rich and lean
Yes at the start it ran ok then started flooding itself after heating up.
@@BrucesShop I know I heard you say that you replaced the carb, the tank as well? Seems like the valve adjustment is OK, compression seems normal, flywheel key OK. hmmmmm
OK, got excited when I saw those cheesy plastic cam gears, thought that might be the issue. The piston does look strange, but who know what they are made of these days... You mentioned the ring gap looked OK, I was thinking perhaps someone ran the engine for awhile with no air filter, or didn't oil the foam properly, letting the dirty air wear down the cylinder. When did Briggs start using the internal governor instead of the old vane style? Guess I have been out of the game for awhile....
Hi Bruce....lawn mowers being strange beasts is hitting the nail right on the head!!
I like the air compressor trick to add air!
I love these little engines almost as much as I love the Quantums....too bad it didn't end up like the Pastor's Craftsman.
Right on I thought it would be fun to show.
@@BrucesShop
It was fun and educated to watch.
Interesting stuff, never seen a blackened piston before. I thought it was rings when you couldn’t find a fault anywhere else. Got shown a picture today of a utterly smashed piston from the engine of a fishing boat. Engine was recently rebuilt, whoever rebuilt it got the timing wrong.
I wonder if this piston has pin holes in it I will check.
Wow that's something different how it blue up. thank you for the video
Thanks for watching!
That vernation in RPM is a classic sign that the diaphragm is being sucked in on the inside of the carb .
Thanks Chris.
Bruce, I once had a quantum that was all coked up on the head and had a real bad ridge on the cylinder also. The person had the wrong plug with wrong heat range and wrong gap. Was incomplete burn and caused the bad running and the coking. Cleaned it up, new plug and it ran fine.
OK Thanks that is a great point.
Very interesting Bruce! Never seen that before.
Glad you enjoyed it
Lawnmowers I get free always have too much oil or not enough & always dirty! Great video Bruce!
Thanks for sharing!
Very nice Autopsy! Thank you!
Thanks for watching!
Interesting tear down Bruce
Thanks. I always learn from them.
Listening to that engine running bruce my 1st job (after changing the d&g) would of been checking the air intake tube for cracks or damage, everytime i service 1 of these old briggs classics i always tighten the 2 bolts holding the tube on as they tend to vibrate loose
You are right to look at the intake tube. If the intake tube was cracked or loose it would be running lean by letting in more air. I did checked it to see if it was plugged. Sorry I did not show that. I thank you for joining in.
Wow great detective work on isolating the trouble. I would have been scratching my head for sure. Hopefully that kind of trouble isn't very common.
I hope so too
Good day Bruce Very interesting video. I could not figure out, but piston does look very dark
Thanks
Thanks 👍 I have had a lot of comments on this one.
Very thorough inspection. I think if I would have gone that deep into an engine I would have rebuilt it with a new brand new piston and rings possibly new valves. I also would also seat the valves to be sure of a perfect seal. It would probably be as good as new. If that didn't fix it I would get a brand new carburetor and diaphragm. It would be extremely hard for me to take an engine down to the crank and not put new life into it. Couldn't do it.
Right on. I was worried that the cylinder was toast as well.
@@BrucesShop true hmmmm maybe try a new set of piston rings. That is probably what I would try and if the cylinder was lightly damaged I would maybe try my luck with a cylinder hone to smooth it out best I could. I have seen it work beautifully with two strokes. Not the same as new but close to it.
Time to ask Santa to bring you a leak down tester while your in Mexico. This helps pinpoint internal engine issues without teardown. It is almost like someone opened the get in the carb and it is flooding with too much fuel and it got better when you provided more air to balance it out.
Right we talked. it runs good for 30- 45 seconds then floods after it warms up.
Good autopsy Bruce!!
Thanks!
So insufficient compression lead to incomplete combustion, didn’t see that one coming.
At the begining it ran ok for 30 seconds or so.
That does look like it got hot. Maybe it had the wrong oil in it. Great video Bruce.
Could be. It may have no oil at one time. After the video i said to myself. "That is why it was found at a dumpsite."
I'm glad you did the autopsy cause it would bug you not knowing what was wrong. Too bad, looked like a nice mower. Thanks Bruce. Stevo
Thanks again
I think you mean the carburetor is on top of the gas tank 😂 I believe that Murray is owner by Briggs and Stratton now
If I said ti wrong sorry. Thanks for keeping me on my toes.
@@BrucesShop anytime Mr Pender 😎👍👌
I would bet on the piston having a pinhole(or a dozen). The other thing I was thinking about was the little ridge you mentioned at the top of the cylinder... Maybe the entire bore has changed over the years and the rings aren't as tight as they could be?
I wondered that as well. I think the cylinder got hot as well. I have the block and will have a closer look. Thanks.
Tighten the head bolts
Good point. when it was cold it mamaged to have a bit of compression. Thank you!!!
😊👍
Mange tak, sir, jeg håber, du nyder min kanal
I had one do that and a littl screw had gotten stuck or sucked down the carb through the intake and clogged the intake tube
You are lucky it didn't make into the cyyinder
Do you happen to know where I can get one of these carburetors? Thank you
Just google this. Lots of choices Briggs classic carburator
are you sure it didn't have to do with intermittent spark? coil or plug?
Good point. As it ran OK for 30 secondes. The piston was burnt though. I thank you for helping me to look back on this one.
no doubt you are right , but a lot of the time if the rings etc are shot there will be a lot of blue smoke black is usually gas. @@BrucesShop
Such a shame on that classic engine. Usually they are bulletproof engines never seen a piston that dark on there.
Yes I was surprised as well
Coil or plug was your problem. K.i..S.S..
OK