OutdoorKing Repair Forum Forums Repairs and Maintenance Questions on Engines Questions On Briggs & Stratton Engines Briggs 375

I am messing with a Briggs 375 on a mower, Drill starting it is fine, (takes a few revolutions to get it to fire) It runs nicely, no rattles or smoke it is just that I can't get enough revolutions out of it on the pull start to get it going. I was going to scrap it but it runs fine once started. Any thoughts? I have changed the coil and that made no difference and neither did swapping the plugs around. I'm guessing maybe a valve problem as this motor has been sitting around for many years. I'm thinking that if I use it to mow my lawns the valve problem may seat itself down properly? I wanted to try that today but we keep getting this rain

Hi Norm,

I've been caught out so many times changing coils from one motor to the next and they don't work ,so I always like to
take a coil from a good running motor when looking for problems but you don't seem to have as many mowers as I've
had with coils not working.


The first thing I usually do is check the compression so it's at least 50 psi.You could check valve clearances.

If it's low make sure the head gasket isn't leaking.

I've had a lot of motors do what you say they need a lot of spinning to start when they have very low compression but you can
feel that when you turn the motor over.

If it's a valve problem it could come good again after using the mower under load to cut grass.

You could also look for a broken or split or leaking intake manifold and check the carby O ring ,I'd check the exhaust isn't partially blocked.

Cheers
Max.

Hi Max,
I have a mountain of coils and unless the motor has a rod through the side I spin the motor up and check for spark so all the ones I have here have been tested so I am always sure they are ok. Motor runs very well once it fires so it is a bit of a mystery to me

Hi Norm,

Have you tested the magnet on the flywheel with a screw driver as sometimes they loose a little magnetism and you only
get a stronger spark the faster the flywheel spins.

I've had a ton of coils break down once they get warm so I don't trust a coil test when the coil isn't under load, also had
a lot of old coils that have weak spark and the engine gets a popping noise (like a miss fire) out the muffler.

Cheers
Max.

Just note that if this is a side valve engine they do tend wear the valve clearances to to zero. This will cause hard starting as the clearance approaches zero. Usually it is the exhaust but can be the intake too.

Hi AVB,
yes it could be valve clearance, but these motors are not worth spending time and money on because you will never get your money back. 50cents a kilo is what the scrap man pays for them

I've had a few of the sprint 375 motors that after checking most of the usual things and not finding anything wrong ,I've
ended up throwing them out as scrap but have taken the lower case off first to have a look and the motors have been
run with low oil at some stage as the plastic cam has very worn lobes.

I've scrapped a lot of good 4 stroke motors Norm ,not worth spending time on them it's quicker to pick up
another free mower and fix that ,a couple weekends ago I picked up a few mowers with nothing much wrong with them
and only put new oil in one ,after the weekend of getting them working they were advertised and 7 mowers sold in 7 days
and the lowest I got for a mower was $100. ,summer isn't too bad for selling but any other season I'd have to sell at $50 a mower
also didn't spend a cent to fix them apart from a little oil and fuel.

Normally I wouldn't bother picking up mowers for free but I saw one that looked way too new and went back to pick it up
an hour later and it was still there and kept finding more on the way home.

Cheers
Max.

Have to agree as most consumers here are just too cheap to repair them. Besides bewteen the parts costs and my labor they can buy a new Walmart mower for less.

Yes that is the way it goes. People moved in next door a couple of years ago, biggest block in the estate and they bought one of those 16 inch Yardking Chinese mowers. I used to hear the poor mower slogging its heart out for hours on end and constantly stalling. The other day I saw the Jims man there and he was there for hours, can't imagine what that cost. If they spent the dollars and bought a Honda they would have it for years to come but they always want to cheap out

This is something i have wondered about. Why such small width mowers? Here the common size is 21 inch. Even with a 21" it seems to take a long time to cut a half acre lot.

Hi AVB,
here with all the new housing estates the front and rear (if you get one) yards are so small that the nature strip in front of the house is often bigger. I also delivered one of these small mowers to a newish house that had no way into the back yard so the mower had to be carried through the house

Otherwords you guys are packed in like sardines in a can. I would have thought being as big as Aussie land is they move apart more. But of course something like just kill you too.

I would go completely bonkers if I lived like that.

Hi AVB,
it is all the grubberments fault, they just keep bringing in thousands of people every year and dumping them into the cities. Still plenty of bigger housing blocks in the inner suburbs but as the people in them die off they are snapped up and blocks of units are built on them. Australia is a big country but the major part is desert type outback. Most population is along the east coast and along the south east

Sorta what they doing here lately. They use to buy up farms and convert them into subdivisions. But lately it is no longer single residential housing but is multi story apartment complexes. Either way I hate seeing highly productive farm convert to buildings and parking lots.

Just simply too many people for the land to support food wise. And we here do have a problem in immigrates too. They just coming by the millions every years. It would be nice if all the warring fractions would just stop and learn how to live together peacefully then there would be this migration problem.

Well I mowed my lawn with the Briggs today, and it runs fine, but I can still only drill start it so looks like the scrapper for it

Hi Norm,

Sounds like there is a mechanical problem as all the good ones I've had you push the primer bubble when cold and they all start first go
after a service.


Cheers
Max.

Might just keep it to mow my lawn, but I usually am always looking for a lawn to mow so I can test a mower