Vintage Briggs mower starting problems

[Hollywood]

I have an old Briggs mower, I'm assuming from 1963. I have to start it by putting gas into the carb. Once started, it has to run on full throttle otherwise it'll stall, it also wants to stall when mowing at a sloped area of the lawn. So today I mowed the lawn and ran out of gas. I put in fresh gas and now it doesn't want to start even though I put fresh gas into the carb. Can someone please help me figure this out as I wanrt to restore this mower.

[Luv2Wrench]

Please excuse the obvious question, but have you been using Ethanol free gasoline?   If not, then you might need to rebuild the carb as that alcohol will have dissolved anything and everything rubber. 

The issue on slopes (and possibly your current issue) is a plugged bowl.  Have you checked the float in the fuel bowl (bottom of the carb)?

[MCHinson]

Regardless of what type of fuel you are using, you need to rebuild the carburetor. Carburetor kits are probably still available and the job is not too difficult (although it has been a few decades since I have rebuilt one of those).

[Bill Harmatuk]

Change the rubber diaphragm between the carburetor and gas tank.

Its a simple job.

Remove tank and disconnect throttle linkage.

Use a phillips screw driver to disconnect carb from tank.

The rubber gasket has an indentation where a round ring and spring sit. This acts as a fuel pump that works off of vacuume from the motor.

Good luck.

Put the whole mower on a table to work on it. It will save your back and knees.

While you have the shroud / recoil starter off.... Clean the flywheel outer surface with fine sand paper. Clean the coil surfaces also.

Gap the coil to flywheel with a paper match book flap.

 

Bill H 

[Bhigdog]

That looks exactly like one I had that had the same problem. Always stalling and hard to start. The fix was pretty simple. I put it at the edge of my woods, reved it to full throttle and shot it in the head with my 270 Winchester. Then I bought a new Honda mower. End of problem............Bob

[JACK M]

I would bet that your local mower shop will have a kit for that carb.

As stated don't forget the fuel pump. (probably in the kit).

[bob staehle]

X2 what Bill H said, my $.02 check the screen on the bottom of the carb pick-up, clean the sump in the bottom of the gas tank .   Bob

 

[cutlasguy]

I always add Stabul to my gas can when I fill it up! This gas goes in my sno blower and lawn mower and I never had any problems. Most people forget to change the oil in both items. The manufacturer gives you break in oil when new with the intention that you drain it after 10 hours of operation and replace it with new 30 weight. Do it!

[TerryB]

Years ago I shared a large farmhouse rental with another engineer from where I worked.  We were both car guys and rented the place as it had a huge garage and gave us a place to work on our auto and motorcycle projects.  Part of the rental agreement was to cut the grass on the property.  We bought some really old cheap push mowers to do the job.  One was similar to the mower pictured here except it was self propelled but that feature did not work so well.  After using that hard to push mower one day I shut it down

using the metal tab it had to short out the spark plug as the normal shut off on the speed control no longer worked.

 

As the engine died out it gave a backfire through the carb which caused the carb to catch on fire and the mower burned to the ground.  I rushed in to the house to tell my friend the good "bad" news that the mower we hated had finally died.  We later celebrated its demise with several cold adult beverages and pizza!

 

Thank you you for posting your mower picture and reminding me of that great day long ago.

 

Terry

Edited August 19, 2016 by TerryB (see edit history)

[JamesBulldogMiller55Buick]

rebuild the carburetor and fuel pump as described above

use non-ethanol gasoline

and that mower will last another 52 years

[c49er]

Rebuild the carb . Easy.

I have a couple mowers with that engine and I just use std every day gas.

No issues at all. I did finally have to rebuild one carb about 5 years ago. 1/2 hour later all was well again.

[Dandy Dave]

Those Diaphragms in the Carburetor use to be about .25 cents for a new one at our local NAPA when I was a young pup.  Cured many a hard starting mower with those years ago. Some of them you could either adjust it to idle, or to run full open when the diaphragm was on it's way out. Those were the days. Dandy Dave!

[Hollywood]

I recently had the carb redone and I've used this mower all summer, but I still have problems getting this mower started. Sometimes it'll start within two or three pulls, but for the most part it'll take a lot of pulls and sometimes it won't even turn over at all. I think it's a gummed up fuel line, because the mower will eventually start and once it does, it purrs like a kitten and it no longer leaks gas from the tank. I hope I can get this fixed. I also think that the ignition coil might need to be replaced, it's loosely connected.

 

Edited December 29, 2017 by Hollywood (see edit history)

[Larry Schramm]

Points need replacement or cleaning or adjustment?

[Ivan Saxton]

A number of those little B&S engines that I have seen have no threaded valve clearance adjustment; and the valves recede into their seats until there is not enough compression to run.  You can shorten the valve stems slightly to restore tappet clearance by carefully grinding the tips on a bench grinder with suitable care and suitable fine grit wheel if your hand and eye are good and steady enough.  You can build up the valve faces with cobalt  "Stellite" rods, using an acetylene rich feather on the flame  to "wet " the valve face with the filler rod when it starts to "sweat".  Then you have to grind the face to the correct angle.  Or you can make, fit, and face new valve seat inserts from something like 4140 steel.  It depends how much you love your mower.

They were built a bit like a cigarette to burn hot for awhile, and then  throw away..   Later mowers are bigger and last    better.   

[Uncle_Buck]

5 hours ago, Ivan Saxton said:

A number of those little B&S engines that I have seen have no threaded valve clearance adjustment; and the valves recede into their seats until there is not enough compression to run.  You can shorten the valve stems slightly to restore tappet clearance by carefully grinding the tips on a bench grinder with suitable care and suitable fine grit wheel if your hand and eye are good and steady enough.  You can build up the valve faces with cobalt  "Stellite" rods, using an acetylene rich feather on the flame  to "wet " the valve face with the filler rod when it starts to "sweat".  Then you have to grind the face to the correct angle.  Or you can make, fit, and face new valve seat inserts from something like 4140 steel.  It depends how much you love your mower.

They were built a bit like a cigarette to burn hot for awhile, and then  throw away..   Later mowers are bigger and last    better.   

 

"Later mowers are bigger and last    better"   

 

Yes and no.  They are bigger in price now that OSHA and EPA mandated regulations have been heaped on all the manufacturers.  And they are bigger in weight and complexity as a result.

Since the fall of 1963, my family has owned this 1964 model Lawn-Boy.  It has been in continual use ever since.  Soon, the 4th generation will be pushing this oldie but goodie around the yard.  Lawn-Boy was owned, then, by the Outboard Marine Corporation.  It was a well engineered product that may be to rotary mowers as the Model-T was to automobiles.  A magnesium deck, unique aluminum alloy 2-cycle engine provided lightness in the decades before OSHA/EPA regulations.  In fact, there are no cable controls to cause breakdowns and/or down time.  Turn the valve on at the bottom of the gas tank, turn the on/off switch to on, prime 3 times, then pull the starter (which pulls straight up in a more natural movement - clever).  Sure, we have maintained it over the years, but it has never hard failed in 54 seasons of use !!  I'll wager not over $100 has been spent on parts in those years and any and all mechanical work has been done at home.

 

"Last better" ?  Thats not been my experience, at least with this swell mower.  Some things mechanical are just a pleasure to own and use.  Period.

 

Sadly, you can no longer buy a Lawn-Boy or any other mower today with the combination of lightness, powerful - easy to maintain 2-cycle engine, wheels that last and sturdy - rust proof deck.  Lawn-Boy today exists in name only.

 

Take a gander in ebay for Lawn-Boy mowers.  You'll see that they are still sought after with prices varying accordingly. 

 

With a little larceny from the movie 'Apocalypse Now', I can honestly say, 'I love the smell of a 2-cycle engine mowing grass in the morning' 

[Bleach]

[Frank DuVal]

Yep, the local dump container ddeicated to lawn equipment is full of dead* new-fangled stuff that people gave up on.

 

I also still use the 60s era Clinton and B & S  engined mowers. Not an issue, besides cleaning the carb, since I use pump 10% fuel in them.

 

No way, no how am I buying one of those overweight over-safetied new mowers. 

 

*probably just a carb cleaning would get 90% of the dump's intake back in use.

 

SO, Hollywood,  have you unscrewed the plug, laid it against the head or other metal surface while still attached to its wire and see if it sparks when the cord is pulled?

[Bhigdog]

After I shot my B & S engined POS in the head (see post #5) I bought a Honda 21" push type mower. Used it for for maybe 10 years before buying a zero turn. The entire time I used it I'd put it away in the fall and in the spring add gas, pull the cord and it started on the second or third pull. Never drained the gas. never changed the oil. I don't think I ever needed to add oil. After I bought the zero turn I stuck the the Honda in the corner where it sat unused for another 10 years or so. Never drained the gas. Just parked it.

Last year a friend said she needed a small push mower. I said "I have an old Honda you can have". I pulled it out of the garage. checked the oil, yup still full, added gas to the dry tank, pulled the cord and it started on the fourth pull. Ran like a clock.

I sharpened the blade, gave it to the friend and she's been using it ever since. Says it starts on the first pull every time.

No moral to the story. Just telling it like it is for whatever worth it is.............Bob

[old car fan]

A good carb cleaning will do,and still out last the Honda,heck already did.

[Alfre]

Check the flywheel key B&S use a soft key and it will ware of sided.

[Frank DuVal]

Right, the soft Woodruff key on the flywheel was to lessen the tendency for the flywheel weight to bend the crankshaft when the blade hits an immovable object.

 

I have replaced several over the years. Typically it just won't start because the spark timing is so far off when the key gets twisted/shorn. The plug will spark, but not fire the engine.

[SMB]

clean the air filter.   Add an electronic ignition module.

[John_S_in_Penna]

It's always interesting to see old equipment well preserved

or restored.  You'll have something different after you restore

your antique lawn mower.

 

At the national Reo Club meet held this year in Pennsylvania,

along with 50 or more cars, there were some restored

Reo lawn mowers.  I had never seen or heard of them before.

[Frank DuVal]

Wow. Reo mowers were seen around here in the 50s. I used a reel type Reo to power my go-kart back in the early 60s. Dad sold the mower attached to the go-kart body when I out grew it.

 

Oh, Man, does this bring back memories: