Small Engine Repair

[Jim Koepke]

My rototiller has a 6HP Briggs & Stratton engine that is acting up. This is a Sears sold item that is about 15 years old.

My guess is it has a stuck valve. When trying to start it it turned over a few times, then froze solid. Removing the air filter exposed a lot of liquid. My first thought was some how water got in, but that didn't make sense being it was stored in a dry place. Removing the spark plug allowed the motor to be turned again accompanied by a shower of gasoline.

My experience with mechanical things is enough to give me confidence to rebuild it myself. That would require acquiring a manual which isn't a big deal and taking the time out of my other activities to do the work. Gosh, if it was clear to me that retirement would keep me so busy it may have been my choice to continue working... I miss the naps. :eek: (that's just a joke, btw, my recollection is of only falling asleep a couple of times once my graveyard shift days were over)

Another option would be to take it to one of the shops in town, most of which are unfamiliar to me.

Finally buying a new rototiller would be the third option.

What ideas do others have?

jtk

[Tom M King]

Might just be the carburetor. Sounds like the float might not be floating, which would not close the needle valve, which would not stop the flow of fuel. I'd check the compression, and spark. You shouldn't need a manual. If those are good, it would be worth rebuilding the carb. If it didn't have good compression, I probably wouldn't bother to rebuild a 6hp B&S, but try to find a Honda to replace it with.

All you'd need would be a carb kit, carb cleaner, and a white dishpan. The first two things would be mandatory, and the white dishpan for obvious reasons. Briggs and Stratton carbs are really simple. All you really need to know, that's not obvious, would be the starting number of turns for the jets, which should be in the instructions with the carb kit, but if not, should be easy to find online.

[Tom M King]

With the engine model, and serial number, you can probably find a carb kit for it on the auction site with free shipping. If you order it from one of the parts replacement specialty houses, it will cost several times that.

[Dave Lehnert]

Not much to a small gas engine. If you have the time it is good experience to work on.
Having said that, Before buying a new tiller or spending a lot of $$$$ on parts I would just go to Harbor Freight and buy a new motor.
https://www.harborfreight.com/65-hp-212cc-ohv-horizontal-shaft-gas-engine-epa-69730.html

My experience with mower shops. It is going to cost $100 to have anything done.

[John K Jordan]

Might just be the carburetor. Sounds like the float might not be floating, which would not close the needle valve, which would not stop the flow of fuel. I'd check the compression, and spark. You shouldn't need a manual. If those are good, it would be worth rebuilding the carb. If it didn't have good compression, I probably wouldn't bother to rebuild a 6hp B&S, but try to find a Honda to replace it with.

All you'd need would be a carb kit, carb cleaner, and a white dishpan. The first two things would be mandatory, and the white dishpan for obvious reasons. Briggs and Stratton carbs are really simple. All you really need to know, that's not obvious, would be the starting number of turns for the jets, which should be in the instructions with the carb kit, but if not, should be easy to find online.

That was my first thought too, gasoline draining into the engine. Might just be gunk on the float valve seat but a carb rebuild it is a no-brainer - inexpensive, quick & easy to install, and likely to fix things. Take the float out - if it's bad you can probably hear the gas inside when you shake it.

JKJ

[Bruce Wrenn]

Karters are now using the HF motor mentioned above. Cost less than 1/3 of what a B&S costs. Only down side I see is metal gas tank. For your engine, look on ebay for either carb kit, or whole carb. Be sure and change oil in engine before starting, and again after a few moments running. Oil will have gas in it, which will wipe out engine quickly.

[Bill Dufour]

flat head engine? If you do have to do valve work a drillpress makes a dandy valve spring compressor. Keep the bad valve someone here mentioned they make a nice bunisher for edge tools.
Bil lD.

[Wayne Lomman]

It sounds like hydraulic lock from stuck needle valve in the carby filly the cylinder with fuel as others have said. Pull the carby apart, clean it and it should be a goer. It happens with gravity feed fuel systems. My '52 David Brown is a shocker for this. I have to make or adapt a new needle and seat as I can't find the original parts anymore. Cheers

[Jim Koepke]

Thanks all for the ideas. Sounds like a good place to start.

jtk

[Nicholas Lawrence]

I have fixed a lot of stuff by typing “broken XYZ” into Youtube. There are a lot of electrician/plumber/auto repair/appliance repair types who have made very good videos showing how to fix the things they know about. I have not needed to do that with small engines, but would be very surprised if someone has not made a video showing how to troubleshoot that engine.

For household appliances there are also companies now who sell repair parts direct to the customer. Some have videos on their website showing how to test to figure out what part is bad, and what to do to fix it. They make money selling you parts, so they make money by showing you what part you need and how to install it. There may be similar companies with small engine repair.

[Robert Engel]

Option #3 :-D

[Jim Koepke]

Option #3 :-D

The equivalent model is on sale now for ~$690 down from ~$998.99.

As folks advised, today the carburetor was inspected. The float seems to be okay. The shaft it was on was kind of sticky and the seat for the needle valve looks like it may have not been sealing well. The rebuild kit has a new needle valve and seat. The kit also has a new shaft for the float but no new float. Guy at the counter in the store said the floats seldom fail. Looks like it needs some cleaning and a few changes of oil to get back to work. May have time tomorrow after going into town.

jtk

[Tom M King]

Probably needs a new fuel filter too. Also, it's probably old enough that the fuel line is rubber. Ethanol may have eroded the inside of it. I'd replace the hose from the tank to the carb, with a new filter.

[Dennis Peacock]

I just rebuilt a carb on an old B&S engine. Total cost of all the parts - $23 + about an hour labor for me getting it done.

You got this John!! :D

[Justin Koenen]

Jim, Go to amazon with your specs for your engine and buy a new carb for around $15 or so. Why fuss with repair? Justin

[Jim Koepke]

Jim, Go to amazon with your specs for your engine and buy a new carb for around $15 or so. Why fuss with repair? Justin

Kind of late now, bought the kit, rebuilt the carb, changed the oil a few times and now it is running fine.

Thanks all for the help and pointing out the likely culprit of the fuel float system not working properly.

My wife wants me to extend her thanks.

For me it has been over 45 years since doing an engine, carburetor or ignition system work. When my skills were getting good at rebuilding and modifying carburetors everything changed to fuel injection. When my knowledge of voltage regulators got good enough to repair a dead one, everything switched to alternators. At least distributors and coils held out for a while before everything ignition when electronic.

After learning a bit about vacuum tubes it occurred to me transistors were a better investment in education. Now even the world of tech where my living was made is way out ahead of me.

Thanks to all again,

jtk

[Tom M King]

Turned out to be a Lot cheaper than buying another tiller.

[Jim Koepke]

yep

jtk

[Mike Cutler]

Jim

I use SeaFoam, added to the gas with all my small engines, and when I put them away for the winter I run some SeaFoam through them, and then run them dry. Keeps everything clean for spring.
Speaking of which, I need to do my snowblower,:eek:

[Jim Koepke]

Jim

I use SeaFoam, added to the gas with all my small engines, and when I put them away for the winter I run some SeaFoam through them, and then run them dry. Keeps everything clean for spring.
Speaking of which, I need to do my snowblower,:eek:

One of the local dealers is selling a gas mix from Stihl which is supposed to help keep two stroke engine carburetors from clogging. It seems to have been effective on my weed eater over the winter.

That thing has been a carburetor clogging PITA!

Unfortunately the stuff isn't cheap.

jtk

[Nicholas Lawrence]

When I bought a new mower and weed eater last year they threw in a gallon of that pre-mixed stuff for the weed eater. I did not think much of it, but have been surprised how little of it I have used. I think I filled the tank twice last summer?

Same with my mower. I bought a two or three gallon can (regular gas for the mower) filled it at the beginning of the summer, once over the summer, and just refilled it for this summer. Both the weed eater and the mower seem to be a lot more fuel efficient then what I remember as a kid.


One of the local dealers is selling a gas mix from Stihl which is supposed to help keep two stroke engine carburetors from clogging. It seems to have been effective on my weed eater over the winter.

That thing has been a carburetor clogging PITA!

Unfortunately the stuff isn't cheap.

jtk

[Tom M King]

I've had no trouble with any of the small equipment since running non-ethanol gas. It's available at almost every gas station around the lake now. Some years ago, the one place that was selling it stopped without putting up a sign that it now all had ethanol in it. Most of my Stihl equipment was bought before 2000, so not made for ethanol.

It was never a worry sitting for months with no ethanol in it, but since I had run it in everything without knowing it, I ended up changing something like 8 carburetors the next Spring. Fortunately, they're pretty cheap on ebay w/free shipping.

At that point, I started removing the ethanol from premium gas, but after another season, other marinas here started selling non-ethanol, so I quit mixing water in the gas to get the ethanol to settle to the bottom of my still, and just went back to buying it.

We run 10 to 15 gallons of non-ethanol here, every week, just keeping up our place, so someone who runs a couple of gallons through newer equipment a year, might think that ethanol doesn't matter, but the situation might be different for the engine.

The Stihl synthetic 2-stroke mix (silver bottles)is good stuff. I've never scored a cylinder on anything running it, even being years old, and some of it getting run all day long at least once a week in grass growing season. The Stihl Dino mix, in the orange bottles, runs dirty, and will clog up the exhaust screen in a small motor in just a few gallons. If you run as much as we do, it's cheaper to buy it in large sizes than the little bottles.

[Jerome Stanek]

I haven't had any problem with my Stihl trimmer with regular gas and their oil

[Tom M King]

It matters both when they were made, and how much fuel gets run through it. Since they started using synthetic rubber, especially for contact with ethanol, it shouldn't matter. I don't remember what year that was. But if it's an older one, like most of my equipment, it does matter. Most of mine were made before the year 2000.

If you run a couple of gallons of fuel, mixed with the Stihl dino oil, in the orange bottles, through a string trimmer, or small chainsaw, the spark arrester screen in the muffler will need cleaning, or the engine won't rev up. You don't have to take my word for that-just check on pro small equipment forums. edited to add: It might be more than a couple of gallons, but I do remember that it's not a whole lot. I haven't run their dino oil since the 1990's.

I've had zero problems of any kind running the synthetic oil, in the silver bottles, and the amount of fuel run through something doesn't seem to matter. Stihl's automatic extended warranty is if you run their synthetic oil.

Even my newer stuff, including riding mowers, gets fed nothing but non-ethanol, and I've not had any sort of problem with them, other than just plain wearing out mechanical parts, and belts.

[Bruce Wrenn]

One of the local dealers is selling a gas mix from Stihl which is supposed to help keep two stroke engine carburetors from clogging. It seems to have been effective on my weed eater over the winter.

That thing has been a carburetor clogging PITA!

Unfortunately the stuff isn't cheap.

jtkBe sure and buy non ethanol gas, and add Staron to the can on fill up. Seafoam is a mixture of methanol (wood alcohol,) naptha (lighter fluid,) and light oil (diesel fuel,) according to the MSDS sheet.

[Nicholas Lawrence]

I just looked using one of those online locators. The closest station that sells gas without ethanol is an hour away. Don’t think I’ll do that to buy a gallon. The Stihl pre-mixed stuff is starting to look more reasonable, especially since I use so little.

Spent some time on the Stihl website. They double your warranty if you buy their pre-mixed ethanol free fuel, and the warranty is void if you use more than 10% ethanol fuel. It looks to me like they think ethanol still matters, synthetic rubber or no.

[Tom M King]

I have seen that high dollar mixed fuel on sale in Lowes, but don't remember how much it was, only that it was a lot less than regular retail.

I've been afraid of the Seafoam stuff because I remembered it's mostly alcohol, and solvents. Back when I was removing ethanol from gas, some tolulene had to be added to re-up the octane. I didn't want to put more alcohol back in though, so stayed away from Seafoam. Fortunately, replacement carbs are cheap for Stihl equipment if you don't buy them from a dealer-off the auction site.