All-Terrain Lawn Tractor Forum
Would you like to react to this message? Create an account in a few clicks or log in to continue.

All-Terrain Lawn Tractor Forum

Like riding lawn tractors through mud, woods, rocks, and snow? Then this is the place for you! Share your ideas, Post your projects and more!
 
PortalHomeSite RulesEventsFAQSearchRegisterLog inBuild-Off

 

 Briggs 14.5 high compression problems

Go down 
+3
B440
Doc Sprocket
Mark288
7 posters
AuthorMessage
Mark288
Member
Mark288
Member


Age : 27
Join date : 2013-01-20
Points : 4351
Posts : 48
Location : Southern Wisconsin

Briggs 14.5 high compression problems Empty
PostSubject: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeNovember 29th 2013, 10:57 am

I got a 97 or 98 mtd for 30$ motor was said to run and tranny case was cracked..ditched the vari drive and made it into a mudder with a dofferent tranny. Well the motor doesnt run for me..the 3 strokes turn fine but as soon as it gets to the compression stroke it is so hard to turn over, even a truck battery wont do it. I dont know what the problem seems to be..i looked at the valves they seem fine. Its a 97or 98 briggs 14.5 hp ohv the model number is 287707 and i have the manual for it. Anyone got any ideas what it is? Thanks
Back to top Go down
Doc Sprocket
Site VIP
Doc Sprocket
Site VIP

2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016

Age : 51
Join date : 2013-04-21
Points : 7270
Posts : 2914
Location : Ontario Canada

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeNovember 29th 2013, 11:05 am

Did you look at the valves, or did you actually measure valve lash? Insufficient lash very commonly cases what you describe.

Also check all your wiring connections including grounds. Failing all that, your starter may be going...
Back to top Go down
Mark288
Member
Mark288
Member


Age : 27
Join date : 2013-01-20
Points : 4351
Posts : 48
Location : Southern Wisconsin

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeNovember 29th 2013, 11:12 am

Doc Sprocket wrote:
Did you look at the valves, or did you actually measure valve lash? Insufficient lash very commonly cases what you describe.

Also check all your wiring connections including grounds. Failing all that, your starter may be going...
I dont think its my starter but ill try n measure the valve lash its got to be something with the valves unless its a thrown rod bearing
Back to top Go down
Doc Sprocket
Site VIP
Doc Sprocket
Site VIP

2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016

Age : 51
Join date : 2013-04-21
Points : 7270
Posts : 2914
Location : Ontario Canada

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeNovember 29th 2013, 11:16 am

If you look in our engines section, you will find links for service manuals. Download yours for specific instructions on checking and setting valve lash.
Back to top Go down
B440
Member
B440
Member


Join date : 2014-01-22
Points : 4156
Posts : 226
Location : Thompson, CT

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 25th 2014, 3:19 pm

It's possible that the valves have been adjusted wrong. It's common practice to adjust valves with the engine at TDC (top dead center), but on these (and most other OPE) engines the engine needs to be 1/4 past TDC. This allows the built-in decompression to work properly after valves are adjusted.

I did this the wrong way once; I couldn't get the motor to crank over even with a truck battery jumping it. Readjusted the valves at 1/4 past TDC and it cranked over fine with just the mower battery.

The Briggs & Stratton website mentions this for valve adjustment.
Back to top Go down
Lawren Wimberly
Established Member
Lawren Wimberly
Established Member

500+ Posts
500+ Posts
2014 Build-Off Entrant
2014 Build-Off Entrant

Age : 57
Join date : 2013-12-21
Points : 4757
Posts : 744
Location : Salem Illinois

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 25th 2014, 4:22 pm

B440 wrote:
It's possible that the valves have been adjusted wrong. It's common practice to adjust valves with the engine at TDC (top dead center), but on these (and most other OPE) engines the engine needs to be 1/4 past TDC. This allows the built-in decompression to work properly after valves are adjusted.

I did this the wrong way once; I couldn't get the motor to crank over even with a truck battery jumping it. Readjusted the valves at 1/4 past TDC and it cranked over fine with just the mower battery.

The Briggs & Stratton website mentions this for valve adjustment.


I agree definitively. This is the most common prob with an OHV. They will need to be adjusted just about yearly. Dunno why they go out of adjustment, just know they do.
Back to top Go down
Doc Sprocket
Site VIP
Doc Sprocket
Site VIP

2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016

Age : 51
Join date : 2013-04-21
Points : 7270
Posts : 2914
Location : Ontario Canada

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 25th 2014, 4:26 pm

No argument here.

As for the adjustment... Wear. Cam wear, lifter wear, rod wear, etc etc etc. Normally, these things would go completely unnoticed, if not for the very obvious effect with the compression relief.
Back to top Go down
Lawren Wimberly
Established Member
Lawren Wimberly
Established Member

500+ Posts
500+ Posts
2014 Build-Off Entrant
2014 Build-Off Entrant

Age : 57
Join date : 2013-12-21
Points : 4757
Posts : 744
Location : Salem Illinois

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 25th 2014, 4:31 pm

unscrupulous mechanics will often tell you they had to replace this or that, and charge you a lot of money, when all they did was adjust the valves... 15 ninute job. I caught someone locally pullin that crap on the old ladies next door... I demanded the old part... He brought out a part FOR A COMPLETELY DIFFERENT ENGINE! (the governer for a flathead) I busted his chops, called the owner in, got the man fired (this was a reputable place, the guy was skimming the extra)

JB_4x4 likes this post

Back to top Go down
the54
Member
the54
Member


Age : 30
Join date : 2014-01-12
Points : 3978
Posts : 51
Location : Ontario Canada

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 25th 2014, 6:03 pm

B440 wrote:
It's possible that the valves have been adjusted wrong. It's common practice to adjust valves with the engine at TDC (top dead center), but on these (and most other OPE) engines the engine needs to be 1/4 past TDC. This allows the built-in decompression to work properly after valves are adjusted.

I did this the wrong way once; I couldn't get the motor to crank over even with a truck battery jumping it. Readjusted the valves at 1/4 past TDC and it cranked over fine with just the mower battery.

The Briggs & Stratton website mentions this for valve adjustment.


Buy 1/4 past TDC I hope your referring to 1/4 INCH past TDC. Not a quarter rotation. The book calls for 1/4 inch past TDC.

JB_4x4 likes this post

Back to top Go down
Doc Sprocket
Site VIP
Doc Sprocket
Site VIP

2500+ Posts
2500+ Posts!
2018 Build-Off Entrant
2018 Build-Off Entrant
2021 Winner of Winners
2021 Winner of Winners
1st Place Build-Off 2016
1st Place Build-Off Winner 2016

Age : 51
Join date : 2013-04-21
Points : 7270
Posts : 2914
Location : Ontario Canada

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 25th 2014, 6:30 pm

Isn't it funny how we all just ASSUMED that he MEANT 1/4" and not 1/4 turn? Very Happy
Back to top Go down
MowBandit
Member
MowBandit
Member

2014 Build-Off Entrant
2014 Build-Off Entrant

Age : 28
Join date : 2013-03-16
Points : 4701
Posts : 477
Location : Haddock,Georgia

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 25th 2014, 10:45 pm

if i was you i would pull the intake off remove the valve inspection plates turn the engine over by hand and make sure all the valves move if one dosent i suspect the cam might have a broken lobe
Back to top Go down
B440
Member
B440
Member


Join date : 2014-01-22
Points : 4156
Posts : 226
Location : Thompson, CT

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 26th 2014, 12:03 am

Hmm. You're right. What I said could be interpreted both ways. I wonder what would happen if you went 1/4 turn?
Back to top Go down
the54
Member
the54
Member


Age : 30
Join date : 2014-01-12
Points : 3978
Posts : 51
Location : Ontario Canada

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 26th 2014, 12:35 am

B440 wrote:
Hmm. You're right. What I said could be interpreted both ways. I wonder what would happen if you went 1/4 turn?

It would probably have very little compression.
Back to top Go down
the54
Member
the54
Member


Age : 30
Join date : 2014-01-12
Points : 3978
Posts : 51
Location : Ontario Canada

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 26th 2014, 12:37 am

Doc Sprocket wrote:
Isn't it funny how we all just ASSUMED that he MEANT 1/4" and not 1/4 turn? Very Happy

Lol for a second I thought a quarter turn but then I re read it and knew what he meant. Just a clerical error Razz
Back to top Go down
TroyBilt Pony
Established Member
TroyBilt Pony
Established Member

500+ Posts
500+ Posts
2014 Build-Off Entrant
2014 Build-Off Entrant

Join date : 2013-06-01
Points : 4762
Posts : 578
Location : West Virginia

Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitimeJanuary 26th 2014, 1:31 am

Is it hard to turn 5-10 revolutions by hand? If not then your starter is croakin
Back to top Go down
Sponsored content





Briggs 14.5 high compression problems Empty
PostSubject: Re: Briggs 14.5 high compression problems   Briggs 14.5 high compression problems Icon_minitime

Back to top Go down
 
Briggs 14.5 high compression problems
Back to top 
Page 1 of 1
 Similar topics
-
» Raising Compression Briggs 12.5 HP
» Briggs 12HP Compression Leak?
» Briggs high rpm screamer
» briggs high performance 16.5 hp
» Old Style Briggs Carb problems...please help

Permissions in this forum:You cannot reply to topics in this forum
All-Terrain Lawn Tractor Forum :: Technical Forum :: Engine Tech :: Briggs and Stratton-
Jump to: