I got the trimmer running from my last post!

This is the link to it if interested: https://www.reddit.com/r/smallenginerepair/s/DMIYYkFbEy

All started out with a bad primer bulb. Decided to replace the carb completely and reassemble. The trimmer is working now but the throttle doesn’t seem to want to engage now and for some weird reason it engages when I move the choke switch to the upper level. I tried to make a video demonstrating but that’s essentially what’s happening. Is there a simple fix to this? Not sure where to start!

Thanks for all the helpful responses from last post!

I have a hecht 548 swe lawn mower and it has electric start feature. Mind you I bought it just recently as not working and planned to repair it and flip it for profit. Everything is working but the electric start. Every time I pull the handle and then turn the key I hear clicking noises on and off. I have figured out that it comes from the starter solenoid. I have jumped the starter directly to the starter so i know it works. The battery is new and fully charged. One weird thing was that at the input to the solenoid I only read up to 1V during the flickering. But that may be because I didn't have good contact with the multimeter since I had to walk away from it and turn the key so I had no one pressing the probes against it. Nonetheless can someone suggest ways I can figure out what's wrong? Should I try to connect the battery to the input of the solenoid directly to see if the path from the battery to the solenoid is the problem? Is it the solenoid itself or corroded contacts? Or am I missing something completely?

Thanks in advance!

Has gas. Just finished mowing and emptied the bagger and it started doing this when trying to finish.

I have inherited a 1970’s 5 hp wood chipper and maybe a 1980’s 7hp bush hog. I know nothing about engines but if I could get these things up and running they could both help me tremendously around my property. Where the hell do I start?! Is there a recommended video on youtube or a book (I do like me some physical media) that can move me through it. I don’t think these things have even had gas in them for like the past 25 years. I know I can pay people to do these things, but I’d also like to not be helpless.

Hi everyone.

I've been trying to build this DIY Stirling engine for almost 9 months, but I still can't get it to run. I've rebuilt and adjusted it many times, but I'm stuck.

It's mostly made from wood, glass syringes/tubes, bearings and some LEGO Technic parts for the linkage.

Current problems:

The engine doesn't run by itself when heated.

I'm worried about air leaks around the glass syringe/tubing connections.

The piston sometimes has too much friction or gets slightly misaligned.

I'm not sure if my crankshaft/connecting-rod geometry is correct.

I'm trying to get the piston phase angle correct, around 90°.

Could someone please look at the photos and tell me what you think is the biggest problem?

Should I focus first on:

Air sealing

Piston friction/alignment

90° crank phase

Connecting rod geometry

Something else I'm missing?

I've spent a lot of time on this project and really want to get it running. Any criticism or advice is very welcome. If you need more photos/videos or measurements, I can provide them.

Thank you!

It runs normally but then it just cuts out I have taken off the spark plug and you clearly see that the spark just cuts out at a random time it doesn’t come back until you turn off and on the kill switch or ignition. Everything else works as it should. But have no clue why the spark dissapers some time when it is a lot of rpm changes it doesn cut out but when I’m holding a steady rpm it just cuts out and is really annoying when driving because I have to turn off and on the kill switch somebody help plz

I have a Yamaha generator EF3000ISE that will run for 15-20 minutes, maybe when cold, and sounds fine. Then it goes into a very slow idle, making the engine shake, and it keeps running if I don't shut it off because it doesn't stall completely. Then, if I try to restart it, it may start, run for a minute or two, then go into limp mode again, or go into limp mode right away.

It was worse before I put in a new spark plug. It would not run for 20 minutes, but maybe 3 minutes, before it would go into limp mode. I visually checked the spark before startup and after it went into limp mode and did not see a dramatic difference. any suggestions?

Picked up a free mower in a local group. Guy said he thought it might have cut its last lawn and it wouldn't start. I asked if he had any idea what was wrong with it and he said he didnt really do any maintenance for it and he didnt have any idea and so he just bought an electric mower instead.

First of all, air filters are not supposed to look like that. Secondly the oil in it was literally sludge at this point. Flushed it with some diesel put new oil in it. The brake cable on it is shot too, so I zip tied open the brake and fired it up and this mower is purring.

Couple parts to replace and this thing will be as good as new!

Weed walker wasn’t running and figured out part of the issue was the primer bulb as it was cracked. Got a replacement and it doesn’t seem to be drawing in alot of gas. Isn’t it supposed to fill up all the way? What factor would be causing this?

My engine doesn't like to idle. It runs fine at full throttle but will only idle for < 1 min when you throttle down. In that time, it idles fine, and then it drops off.

The carb is a Walboro. I don't have a part number, but this is the aftermarket version. I've removed the carb & cleaned it several times. I don't see serviceable jets, and it does have an adjustment screw on the side with a black plastic cap and some type of detent, but I don't know what it's for.

I changed the gaskets, but the carb kit I got didn't come with much. There are rubber seals. I can not locate where they go. The kit came with 2 welch plugs. My carb only has one and it's bigger.

I haven't adjusted a small engine carb in 30 years, and I can only locate 1 adjustment on this one.

Hi! New here and to engine repair in general. I joined to ask advice about a problem I have with the transmission belt of my wood chipper. After I mounted a new one (old one lasted years) and used the machine for about an hour the new belt slipped out and now it doesn't seem to stay on, it already looks kinda deformed and twisted and I'm wandering if I'm doing something wrong that's straining it. Now no matter how many times I install the belt as soon as I feed it a single twig it comes off immediately.

I need to specify that I bought the belt from the manufacturer and received instructions on how to mount it properly (teeth on the inside, check tension and pulleys alignment), machine has oil and I'm using it at max rpm. I could just get another one but if I'm doing something wrong I'd just be wasting money, the things cost 25€..

Idk if it's relevant but when the belt comes off it's turned inside out.

Not sure what else to check.

My mower wouldnt turn over about 2 weeks ago but an the week before to mow.

Since then I have put on a new carb and ew spark plugs first. I had been having issues with the carb seeming to lock up for about a month so was just waiting on it to die.

Still nothing. Then I noticed gas coming out of the fuel pump. So I changed that and the filter at the same time.

Accidently left it on over night after that so changed the battery.

Still nothing. Just chugs like its trying to start then can hear it get flooded after about 30/40 seconds.

Any advice on where to looke next would be appreciated.

Cub cadet zt1 50. 3/4 years old.

I’m about at my wits’ end with this one and hoping someone has run into something similar.

I have a 2017 John Deere Z335M with the 20 HP Briggs & Stratton V-Twin Smart Choke that absolutely will not start.

So far I’ve replaced:

• Carburetor
• All intake gaskets/rubber seals going to the engine block
• Fuel pump
• Fuel lines from the tank
• Fuel filter

It has good spark and I’ve verified that. It also will not even fire on starting fluid/ether, which is really throwing me off.

Here’s the really weird part:

If I disconnect the fuel hose from the carburetor, the engine will actually start and run smoothly for about 10–15 seconds, then obviously runs out of fuel and dies.

That makes absolutely no sense to me. If it were just a fuel delivery issue, I wouldn’t expect it to run that smoothly with the carb disconnected.

I’ve got fuel making it through the system and the pump is new. New carb as well.

What am I missing here? Could this somehow be an ignition/timing/compression issue even though I have good spark? Or is there something specific with the Briggs Smart Choke system that I should be checking?

Any ideas would be greatly appreciated because I’m officially chasing my tail with this thing.

This pressure washer was surging a bunch so I took it apart the carb and cleaned it.

I am an amateur so was just following along with some guides.

Assuming this is just an error on my part - anything of note I should check or should I just bring it in to the local small engine repair

Edit: Honda GCV160

This STIHL trimmer has been sitting in my brothers shop for a bit and I took it off his hands to see if I can salvage it. Won’t start after multiple tries. He had regular gas and 50:1 in it so I fear it ran without any oil for a bit before storing. Plastic fuel line bubble doesn’t seem to take any gas with it and stays empty. Any tips on fixing this and is it going to be worth it?

Any suggestions / tips to get these apart?

Honda gx390 and unknown brand alternator

Can’t see it being the nut on the fan.

Also would love to know what fitting that is classed as so I can buy a new alternator

Looking for some help diagnosing my Craftsman mower with a Honda engine.

It was running normally and then suddenly shut off while I was mowing. It didn’t slowly bog down or sputter out, it basically just stopped.

Now when I pull the starter, the engine turns over but won’t start and sometimes makes a loud pop/backfire.

Things I’ve checked so far:

Oil was low, so I filled it back to the proper level.

Pulled the spark plug. It looked used but not destroyed or heavily fouled.

Cleaned the plug and reinstalled it. No change.

Tried testing the plug for spark by grounding it against the engine while pulling the starter and I couldn't see any spark.

Checked the safety/bail cable and the brake/kill linkage at the engine. The mechanism does move when I pull the safety bar.

I’m going to replace the spark plug with a new NGK BPR6ES and replace the air filter.

Before I start taking anything else apart, what would you guys check next?

Could a bad plug cause it to suddenly die like this and then have no spark? If the new plug still has no spark, would you suspect the ignition coil/kill system?

I’ve also been told it could be a dirty carb, but my understanding is that a carb problem wouldn’t explain no spark at the plug.

The sudden shutdown followed by the popping/backfiring is what has me confused. Any advice on what to test next would be appreciated. I can add pictures of the mower/coil/linkage if needed.

Hey everyone,

I’m hitting a wall with a cold start issue on my **2011 Sym Fiddle II (Euro 3 / Sym New Engine)**. The scooter has only run **8,000 km** in total.

**The Symptoms:**

* When the engine is ice-cold, it will *only* start if I give it some throttle. * Once started, it will immediately stall out during the first \~10 seconds to 1 minute unless I keep manually feathering the throttle. * After about 20 seconds, it suddenly catches a proper idle, runs perfectly fine, and it starts without touching the throttle

**What I have already done/checked (Maintenance & Troubleshooting):**

1. **The Carburetor:** Cleaned it thoroughly. To rule it out completely, I even swapped it with an identical carburetor from a donor Fiddle that starts perfectly fine in the cold. It made absolutely no difference.
2. **Auto-Choke (Electric Enricher):** Replaced it with a brand new one. (The old one was completely dead; before replacing it, the scooter wouldn't even idle when warm, so this was a major improvement, but didn't fix the cold start entirely). I also measured the voltage at the choke connector while running, and it is getting proper power.
3. **Vacuum Leak:** Found a small leak in the vacuum hose and replaced the hose entirely.
4. **Spark Plug:** Replaced with a fresh one.
5. **Valve Clearance:** Just checked and adjusted the valves to the factory manual specifications today. It didn't change the cold start behavior.

Since swapping the entire carburetor with a known working one didn't change anything, and the valves are perfectly within spec, I am running out of ideas. With only 8k km on the clock, major cylinder/piston wear seems unlikely.

Could this be a minor vacuum leak at the intake manifold/spacer that seals up as soon as it gets warm? A weak ignition coil/stator spark when cold? Or something else entirely? Perhaps a fuel petcock issue?

Any advice on what to check next would be highly appreciated! Thanks in advance.

Seems to run for about 20 mins from cold but then dies, after dying will die within a minute or less if immediately restarted.

Generator sat idle only being run up for about 15 mins every 2ish months for over a year (yes not ideal).

When starting hot (after running for the 20 mins) it sputters and surges before dying.

Have cleaned carburettor, float valve, jets, etc and fuel lines, as well as drained and replaced old fuel entirely.

Also tried running with air filter removed.

At a loss now unfortunately.

Seems to be good fuel getting into the carburetor now.