Briggs 5hp assistance

[RitchElbe]

Seeking knowledge assistance ( Meds have my memory flakey ) regarding a briggs 5 hp horizontal.
Friday night.. discovered that some while in dry storage outta the rain.. the engine had water in it..( suspect perv neighbor )
so I drained, flushed with oil twice and suction, then added fresh oil. Fired up and ran like a charm...
Saturday morning.. went out, installed new tines, went to crank.. wouldn't allow pulling..odd...so I threw a pipe wrench to it
worked it back and forth and it started to allow full rotation. Now at one point for a split second.I thought I felt it catch hard
but it kept turning..so now that it's free again I went to crank it.. pulls fine..rotates...but nothing.. I feel no suction in the spark
\plug hole or carb intake but I do feel exhaust thru the carb when I try cranking it... I did remove the head and checked and the
valves are moving freely. Does this thing have some kinda timing I am unaware of or forgotten about?

 

[davesl708]

Sounds like maybe a broken connecting rod.

 

[/pine]

Seeking knowledge assistance ( Meds have my memory flakey ) regarding a briggs 5 hp horizontal.
Friday night.. discovered that some while in dry storage outta the rain.. the engine had water in it..( suspect perv neighbor )
so I drained, flushed with oil twice and suction, then added fresh oil. Fired up and ran like a charm...
Saturday morning.. went out, installed new tines, went to crank.. wouldn't allow pulling..odd...so I threw a pipe wrench to it
worked it back and forth and it started to allow full rotation. Now at one point for a split second.I thought I felt it catch hard
but it kept turning..so now that it's free again I went to crank it.. pulls fine..rotates...but nothing.. I feel no suction in the spark
\plug hole or carb intake but I do feel exhaust thru the carb when I try cranking it... I did remove the head and checked and the
valves are moving freely. Does this thing have some kinda timing I am unaware of or forgotten about?

You might check the key (woodruff etc.) that times the flywheel to the shaft...the water issue may not be related to the later issue...

 

[RitchElbe]

I have broken down all the way to the woodruff...but I popped the head back off and check the positioning of each valve and cylinder.. they seem to be in order of position for intake, power stroke, exhaust.. while I had it off..I placed my hand over the piston itself and it had good suction when I pulled the cord..put it all back together.. gave a pull..nothing.. placed hand over exhaust...lots of out bound pressure.. dropped gas in thru the spark plug hole,,,, replaced pulled several times nothing... which is odd...due to the supper strong spark I had when I have the plug out and grounded against the head bolt.. really odd.

 

[/pine]

have you tried a different spark plug?

 

[RitchElbe]

no need... this one is good. Super strong spark visible in day light as well as feeling it thru the fingers lol

 

[/pine]

no need... this one is good. Super strong spark visible in day light as well as feeling it thru the fingers lol

That is odd...even with poor compression with fuel and spark it should at least pop off...

 

[stuckmotor]

Could there be something wrong with your gas?

 

[stuckmotor]

I didn't quite understand what you meant when you said, " I have broken down all the way to the woodruff." Did you check the aluminum flywheel key carefully? I've been told that sometimes they bend but don't shear completely preventing the engine from cranking.

 

[RitchElbe]

it was a typo///meant have NOT broken down to ... as for gas... fresh real gas...not that ethanol junk
As before.. Friday not it ran like a champ..fired up on second pull to be exact.. 14 hrs later.. nothing

 

[oldnslo]

Do you have compression? Not sure how old of a 5 HP briggs this but possible it has auto decompression and this is reducing your compression to the point it won't fire.

 

[RitchElbe]

I do not have a gauge...no idea who borrowed it.. what I did do was place my hand XXL size over the piston while head was off and pulled.. it was sucking my palm down.. now that said.. There is good exhaust pressure out of the muffler..and at times I noticed it was blowing pressure back thru the carb. Which got me to thinking timing was off or stuck valve.. yet with the head off and pulling several time over 4 mins.. the timing seemed to be in sync for the intake power and exhaust strokes.. with that said.. I have noticed it was bone dry in the combustion chamber. Which tells me it is not getting gas at all.. so I shot some ether into it... but it has a strong spark. Seems crazy since the night before it was running like a champ

 

[oldnslo]

If it is blowing back out the carb your intake valve isn't closing at the proper time. Could be auto-decompression or a piece of carbon stuck on the valve seat. Don't take much to prevent vacuum and compression while starting them.

 

[RitchElbe]

Then I need to break down and break it fully down and check the woodruff.. gonna be fun day for moanday

 

[/pine]

it was a typo///meant have NOT broken down to ... as for gas... fresh real gas...not that ethanol junk
As before.. Friday not it ran like a champ..fired up on second pull to be exact.. 14 hrs later.. nothing

The shaft/flywheel key is the first thing I would check if I had both fuel and spark but no pop...if it's aluminum (or other soft metal which many are to prevent damage) it can be slightly sheared which could also explain what you "felt" (catch hard) when troubleshooting...

 

[stuckmotor]

I've never heard of an engine like that jumping timing but, if you have to go in as far as the timing gears, make sure and see whether the timing marks are lined up BEFORE removing them. It's a mystry to me why you had to put a pipe wrench on the shaft and I would hate for you to reassemble it correctly and solve the problem without knowing what caused it.

 

[Blaneypark]

Had the same problem with an old Briggs. A new shaft/flywheel key and started on the second pull.

 

[5030]

One option is, if you cannot get it running is to replace it with a Harbor Freight Predator of the same size. Cheap and reliable. I've always considered Briggs to be a disposamotor anyway.

 

[KubotainNH]

Definitely check the key but a valve not seating is my bet. I'm thinking it got gummed and stuck which is why it was hard to get spinning and now that sticky stuff is keeping it from moving freely. I've had it happen numerous times on a motor that sat. Sometimes the valve moves but not quickly enough to get good compression because of sludge. The first run of the season may have melted the sludge which reformed into glue when cooled off. Been there....

 

[RitchElbe]

common practice.. unable to get a full turn.. use a pipe wrench to play the shaft back and forth to see if it loosens up any. In this case I could pull the starter rope and get about a quarter pull from it.. thus the pipe wrench it snagged.. done it on several motors that sat for a extend period of years.... and all of those of still running today... this one has chosen to be a challenge