Nice Job James. I have not ever encountered that problem, it's good to be made aware of it. Thanks for the video.

Had to watch this one, really takes me back to the late 70's. My Dad brought home from the dump a lawn mower that was not working. In short order he had it running, he went on to salvaging mowers from the trash heap, fixing them and selling them. Rarely bought new parts salvage one to make another run. This made for a lucrative way to make a bit of extra cash. Eventually he began repairing other folks mowers all out of the shop behind our house. Eventually he rented a store front , then secured franchises to sell new equipment, and do warranty work. Branching off to chain saws, and other small engines. Moved on to buying some commercial property and building a larger shop, which expanded 3 times. When he retired in 1992 he sold the shop and land for a significant amount of money. Not bad for a guy with a grade 8 education that never made it past corporal in the forces after 25 years service.

James I am 75 now and back in 64/65 I was the one lung king of the neighbor hood , so I thought. I did manage to fix all the mowers I collected on the side of the road. I had a claw hammer, 9/16 and 7/16 socket crescent wrench and a pair of pliers, no ratchet. Hours of fun taking them apart cleaning them put back together and when they started it felt great. Thank you for sharing, would have never guessed that was issue. Back then it was one cast piece.

My late father used to do small engine repair as a side job when I was a boy. I used to watch him and this really brings back memories. Fixing things is sadly a lost art these days. I miss my father.

He's right! I never guessed why. This guys small engine skills are way above my paygrade. I'm jealous.

You'd be proud of me. I fixed the neighbor's garage sale purchase mower with a Honda GCV160 motor. It was surging when warm. I immediately suspected a lean condition. Found fine dirt in the tank. Cleaned it out. Took the carb apart, cleaned it, and found the emulsion tube above the main jet had its little holes clogged with the fine dirt. Used a wire from a wire brush and cleaned them out. Mower runs perfect now.

It’s interesting watching and learning how to repair things especially in our throw away society.

I will say I appreciated the end b-roll of sweeping up & cleaning up after the mower great job diagnosing and fixing it!

This is starting to become one of my favorite channels on KZfaq. Your videos at first start off as a unknown mystery, sometimes with twists and turns and often a happy ending. The well placed shots, clear and concise explanations of how these things work make this a quality channel. Thank you for taking the time to share your talent with the rest of us in a way that is easy to follow and digest.

My grandmother always said; "you learn something new every day. When you quit learning, you're probably dead!" I'm 67, I'm not dead yet and I'm still learning!

Briggs is notorious for those plastic cam assemblies failing, they shouldn't use plastic on the cams.

nice! I got a Craftsman 20" like new from the local thrift shop for FREE. The deck and blade barely had any signs of use at all. They said the engine was seized. I pulled it through at the store, it was very hard to pull, but it wasn't seized. Took it home and saw that the 'safety blade stop' cable had broke down at the lever on the engine. Re-attached it and the mower is running fine! FREE! YAY!

extremely helpful and perfectly filmed

It's a shame so many manufacturers have gone to plastic internal parts, simply don't have the reliability of the old school engines

In the world we now live in where everything is a "throw away" item it`s good to see someone taking time to rebuild. Thanks for sharing.

A ranch I worked for had a lot of Briggs and Stratton motors on irrigation lines they were always failing with the same fault. Its pretty sad that a highly regarded manufacturer like Briggs uses plastic cams that can slip.

My first guess was the aluminum key, but I didn't realize it had tinkertoy parts inside. That was a fun video. I mostly work on older stuff, but I enjoyed watching your careful approach, and I learned a few things!

There is nothing more satifying than to take something that has no percieved value to an average person, and make it like new for a few bucks. Good going! That's probably a $300.00 mower!

A pressed on plastic cam shaft I'm surprised it doesn't have a compressed cardboard deck and bamboo cutter blades , good video and great job getting this thing going

Fun to watch a master mechanic solve a problem. Always a good thing sleep on it.

Nice Save! Im surprised it even half started with that timing problem.

A helpful tip: The gas tank fill cap on this and similar mowers was very poorly designed! Grass and other debris collects on the underside of the cap flange and when you remove the cap the debris falls into the gas tank. As an ex lawnmower mechanic I am very meticulous when it comes to using clean gas so when the carb jet on my Toro kept getting clogged I knew something was up. After discovering the source of the problem I did two things. First I installed an inline fuel filter in the short rubber gas line running from the tank to the carb. Do NOT use the little red plastic style filters sold online as they will not filter out smaller particles. Rather use the round clear plastic filters that contain fiber filters. Due to the short distance between the tank and the carb and the overall length of the filter this requires some manipulating but it can be done. Second, and this is very important, before removing the gas cap run a rag around the bottom surface of the cap flange to remove debris. I haven't had a single clogged carb jet in the two years since I diagnosed this problem.

Thanks for the bonus footage!! That was driving me crazy. Briggs use to make such good engines.

Wow after buying 2 new carbs thinking the first was a bad one, i now realize i could have a broke key or timing is off. Both new carbs would run bout 30 seconds and then shut off. You made a Great Video and showed step by step to help us understand the possibility's we might had over looked. You are my hero of the Day. Thanks....

I have a neighbor that bought 2 of these mowers. Both have a failed to start problem. I suspected a broken cam problem. You have shown how simple it is to repair. Great video. Thank you for posting.

When turned upside down, those engines will typically sit perfectly in the top of a standard 5 gallon bucket. It raises it up off the ground so you can work on it a bit easier and keeps everything level.

A plastic gear forced onto a steel shaft and then soaked in hot oil. Perfect!

I bought a New mower Yesterday. My 14 year old Craftsman has been impeccible. It has started on the first stroke every year. Last year however i bought regular petrol and The gas wire broke. NO repairshop is open. It IMPOSSIBLE to get spare parts in Sweden. I cleaned The AIR filter and plug. Thanks for The video.

I have one in my shed my neighbor owns been trying to get it started he didn't give me good history on it changed all the broken cables and break did spark plug cleaned Carb, checked spark still no start I think I am here or got something with compression this video is amazing I got a lot out of it I only wish to get as good as you.

For anyone wondering, don't get the plastic cam , this may have worked for James, but you're better off getting the all metal cam . Yes , it's interchangeable.

Nice work JC, always a calming influence within the small engine fraternity. No stress, no fuss and no rush. A discerning upload!

You are a great mechanic and I will check the timing after seeing your in-depth demonstration I feel like I can get into the guts of this old mower of my brother in law’s and with the knowledge you have freeing given. Thanks for filming this.

Thanks for your time and your knowledge you know when I was a teenager I had a lawn business and about 10 lawns as far as I got on rebuilds was the timing on the flywheel and the key used had to be replaced because I hit something hard I thought it was really doing something back then but now after watching you I think I can dive into the guts of the engine thanks again

Well done James, you should be teaching a small engine course, you would be a good teacher, thanks for sharing your knowledge , you were very helpful.

It's a pleasure watching such professionalism and expertise in action. I dount I'll be tearing into any small engine motors anytime soon but I enjoyed (and learned from) your video so much, I downloaded it just to watch again sometime. Well done and thank you for sharing your expertise.

Now I'm going to open my machines so I can try to fix them myself thanks God bless you and you family

Man the feeling of seeing someone fix something better than new WoW! love it, Thanks James

Thank you for your explanations and accuracy. Learned some points on checking the timing outside and the compression nob. Very clean video.

Excellent video all the way around ! You did a fantastic job trouble shooting the problem, and explaining why the need to remove the motor. Your knowledge to small engines is wonderful. Thanks for sharing !

I really liked the way you worked, clean and methodical.

Wow that was one of the most satisfying engine build I have ever watched Cleary explained from the start to the end.

Impressed! Very good job. As a fellow Small Engine Repair guy who watches these videos all the time, you are by far a very thorough tech. Kudos to you. Very good job and it started on the second pull. Enjoy the new mower.

Thank you, this was exactly the help I needed. Mower is now running great

"Yes! Plastic cam shafts. You don't want them to last forever do you, Mr./Ms. retailer?" It's not a defect it's a feature! I admire how you were able to zero in on the problem, explaining your reasoning and methodology. I grew up on all metal lawn and garden engines (yes, they are very nutritious with whole milk!) If something was out of time, it was game over. I didn't know until now about the plastic cam so if I had run across the problem from the outside of the engine, that engine would go into the metal recycling pile. Thank you for pointing it out! A repair like this, done by the typical small engine repair shop would have been too expensive to consider for most home owners. And that, sadly, is the plan.

perfect instructions on resetting timing..I recently ran over a rock that knocked the timing off and caused this problem..it started once and belched smoke like a champ.. i shut down immediately and it wouldnt start again so i tore it apart to see what was happening but had no idea what to look for till i got this vid. and it worked perfect... thanks amigo.. good job.

Ugh, I hate how cheezy these engines have become nowadays. This is why I try to save the old stuff. So much better quality! I'm glad you posted this vid. It's good to know what's lurking inside these engines.

Because of watching your videos over the last 6 months i was able to fix my first 2 generators could not have done it with out your videos thabk you so much for all you do

Good job getting it going.,

Plastic gears and lobes on a camshaft? This lawnmower is a complete disposable POS. I'll keep my 1976 two stroke Lawnboy that still starts on the first pull. The only maintenance I've ever really had to do it is adjust the points, which as far as I know, was the first time ever in 40 years. The thing is older than I am.

I get so jealous watching this video. I would give most anything to have the skills and knowledge to take something like that apart, analyze the trouble, repair it and put it back together. It just amazes me. Thanks James.

My father started his career as a machinist in the navy. He taught me how to repair all sorts of small engines and even some car and outboard engines. It is a very useful skill that I have never needed even once as an adult. But I'm glad I learned.

Just here to say thanks from the UK. After watching your video a few times and having a Toro 675 GTS failing to start with similar issues I decided to take apart my first ever engine. Same fault as this one with the camshaft sprocket timing out after shifting on the shaft. Followed your video, replaced the camshaft and fired up on the second pull. Many thanks a mower saved from the clutches of scrap.

Nice to watch people fix small engines. Thanks. It would make sense the larger sprocket gear would break loose considering the torque to shaft size. I may need this video for my Sear's mower I had put aside a few years ago not understanding the insides so well. You took a lot of the apprehension out of what seemed an insurmountable job.

Great video and I like how you showed the entire process with a clean machine, can't work on my projects if it's cruddy, I clean them up and makes less mess overall.

Great video. Informative, detailed, and not overwhelming background music drowning out what you're saying.

Outstanding video, very informative and free from unnecessary intro, music, safety information, tools used, long back story, etc.

its pleasure to see someone do a repair properly. there are so many fools that dont know what they are doing posting videos its not funny

I always learn something watching your videos. There’s something to be said about the way you go about things! Your easy to follow and you don’t rush through anything! So many you tubers rush through there video’s with very little information or show the steps needed to do the job leaving you feeling like their main interest is getting subscribers instead of actually putting out helpful information. Guys…You gotta put in the effort and be more focused on the video and not how many likes you get!

Brilliant thanks, I didn't know that plastic pressed into shafts was hidden in these engines. I think the sound it made like the chuff of a steam engine on starter fluid was an indication that valves were popping at the wrong time. Very helpful to us dabblers!

Good information and takes me to the next step diagnosing my riding mower problem, which started with replacing with a new carb, rather than simply cleaning the old. Now it blows fuel back out of the carb, suggesting a valve problem. But I have readjusted them several times with no improvement, resulting in no compression. You now have a new subscriber.. thank you.

Real good troubleshooting procedure and hands on disassembly. Great Video, thanks.

Another outstanding video!! Thanks much. It seemed evident that it was the gear that slipped even without the bonus footage. The decompressor was now being interfered with by the gear. Since the decompressor is fixed to the shaft, but now binding with the gear, then it had to be the gear that moved.

$20 for part but time invested does not make it worth fixing unless you have time on your hands. Now the money you might make from the video and helping anyone watching is priceless.

I have a small engines certificate from my local community college and I must say, I still have plenty to learn. Subscribed to your channel today and hope to get some repair knowledge from a front line mechanic. Thank you for sharing this. I did replace the crankshaft on one machine and it worked fine for a long time after.

Amazing attention to detail brother ! Nice pride in your work! Thanks

I made thousands last summer flipping mowers with this engine. My favorite engine ever. Never ran into this before. Thanks for the knowledge!

Having the key on the crankshaft shear off is a very common problem with these mowers where the engine's crankshaft has the blade directly bolted to it. When the blade hits something "unmovable", such as a rock, the flywheel continues to turn, shearing off the key. The engine then won't start because the spark timing is extremely far off. While common with push mowers, I've even had it on a John Deere lawn tractor, whose engine crank isn't directly attached to the blades; apparently that problem was caused by a backfire or other issue, but exhibited the same no-start symptoms.

I was hesitant to watch this when I saw it was 26 minutes long. Most videos that long tend to have lots of babbling with little real diagnosis and repair steps. This video was properly detailed. I learned a lot. Thank you.

Thanks for taking the time to show the camshaft failure at the end !

Hello James. This is my first time to see one of your videos and I have now subscribed to your channel. It is a pleasure watching someone work who methodically and properly diagnoses problems. It is impressive to see another person who cleans before disassembling, also. Great job on doing things RIGHT!

Ahhh, bring back the old briggs style...never an issue except for plug fouling from worn valve seats..hand lap reface, good aluminum carbs with brass seats and neoprene seals.. Had this type issue on a brand new 7250w generator..out of box..that was a teardown ! Three day fix, started up, plugged into home power, ran fifteen minutes and utility can back on .ha!

You're right! Out of all of the things that it could've been, I would've never thought of this. Thanks.

Makes sense that the gear broke loose, it has the least amount of surface area in contact with the metal shaft. Without splines, pinning or keyway that is where I'd suspect rotation to have occurred. Great video, thanks.

I've always been a big Briggs & Stratton fan boy, and had no idea that they had sunk to that level of installing plastic cams. This really made me sad.

Plastic cams.... Insane. Seems that every time they stick plastic inside an engine, reliability disappears. Good work.

Another good job under your belt. Thanks for sharing with all of us.

Great Work! Not many folks would have gone to that much trouble with that mower.

Very interesting. I thought it would be the lobes on the camshaft that got loose. Your channel has taught me more about small engines than I ever learned in school.

Thanks for that informative video. I have a 14 year old Toro with basically the same motor. It still runs and starts great. One thing that amazes me is that the oil never seems to get dirty. It always looks new on the dipstick. I have a very small bit of lawn. Only a 20 minute job and I only change the oil every 2-3 years with amsoil even though it still looks good.

Perfect, this is the film I needed to see. I think my lawn mower have the same issue. Thank you.

Great Video . We learn something new every day and this is no exception. Real nice to see someone taking the time to teach others how to fix things especially the lawn mowers and yard equipment. I'm however surprised that a reputable engine builder would use such cheaply made parts in their products. Thank you for your for posting this video.

You're right, James, I would never have thought of the cam lobes moving. Just shows the 'designed obsolescence' in making a plastic camshaft. Ultimate stupidity in my opinion. But if the "design" is to last only as long as the warranty, brilliant idea. Thanks for sharing.

Very good. I would not have recognized that issue, and now I know what went wrong on other machines that I couldn't figure out... . Thank you...

Great job! I wish l had a son like you. You seem to be a very good young man. You cut the grass and clean up after you. Most of todays youth wont cut grass for their parents. God bless you.

This is a very satisfying video from start to finish. Just because you did not skip any of the steps made this easy to follow in fact I think it is genius. Even to the final chapter of demonstrating the reliability and cutting ability make for a complete presentation. I even enjoyed sweeping up the debris in your shop. It shows respect for your craft and pride in your work. Now this is what I call a video! Very well done.

I liked the sweep-up end shot. Smart.

Nice work James. Liked your prep work and use of pre-lube as well. Professional level work.

Well done James, i enjoyed the mower repair, you slowly and carefully carried out this job, which i prefer to do. Greetings from Australia 👍

James, I’ve come across this as my sister hit a water shutoff valve in her lawn. I was able to straighten out the decompression valve and drilled a hole for a spring pin to locate & lock the plastic gear in proper timing. My sister has used it for a couple seasons now with no issues. The air trick is a great way to diagnose what's going on.

Nice fix James. You work and explain everything like a gentleman!

Thank you, I have the same problem and your video was very helpfull. That save my second hand lawn mower. I never did mecanic but your video is so good that I fix it by myself!!

What a great job ! I thought about fixing mine after that but I'm not sure I could do all the fiddly bits !

Where's your son? LOL, he should be mowing that yard. I remember him starting a generator for you once. As soon as it started he ran away! Has he stopped running or is he running like Forest Gump? Another great repair. I enjoy watching you methodically and calmly work on things. Slow and steady, no sledgehammers involved...

James you make a great channel with interesting content. Use to love piddling with small engines.

Sounds great! Runs like a champ.

awesome! got 3 of these in the shop with same problem! FANTASTIC video! thank you!!

Your methodical focused trouble-shooting is enjoyable to observe.

First clue there was a problem, it was exactly full of fresh, clean oil. Especially if the mower is under warranty. I've seen engines with broken connecting rods, but they were full of fresh oil! F.Y.I. always remove the spark plug when Workink underneath the mower, I have seen them start and run with the plug wire over an inch away from the plug!!!

great job.felt like we were doing the job together. nothing like being able to fix things

Incredible video! Absolutely clear explanations and such tremendous attention to detail. Thank you!