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Old 09-09-2003, 07:22 PM
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Default Briggs and Stratton 14.5 HP Newbie Question / Story


"Jay von Rosen" PleaseReplyToGroup wrote in message
...
Hi all -

First, I'm new to small engine repair - I'm learning as I go, but I
really want to figure this all out. Quick description of the engine in my
lawn tractor: Briggs and Stratton Twin Cylinder "L" Head, 14.5 HP.

So here's what happened. While mowing my lawn one day, I hear what
sounds like a rock. It turns out that a piston connecting rod broke,
shattering the crankcase cover. So I think to myself that I need to take
this opportunity and learn how to service this thing. I go out and buy a
new connecting rod, a new piston assembly (piston, rings, etc), and a new
crankcase cover, and I set to work.

I replaced all of these pieces, and put everything back together. I
tried to start it, but got nothing at all. I tried to turn the flywheel

by
hand, and couldn't. After a little guesswork, I realized that I tightened
the connecting rod on the crankshaft too much. I got that torqued
correctly, put the crankcase cover back on, and tried again. Everything
turns over, but it never sounds like there's ever any ignition.

By this point, I start the whole troubleshooting routine - check for
spark, and it looks good. Check for gas, and there's gas. I tried

putting
a little gas in the cylinder, and then cranking it just to doublecheck

that
it's not starved for gas. Everything there looks fine.

So then my hunch is that I messed something up putting things back
together, and that I'm not getting good compression. 1 don't have a
compression gauge, and the manual says that Briggs doesn't publish
compression pressures, so I went forward on the hunch without proof,
especially since I realized that I did not replace the head gaskets when I
pulled off the cylinder heads.

I bought new head gaskets, and replaced them. I have to mention that

I
did not torque the heads correctly when I first put them on. I didn't do

it
in the right order, and I didn't get the correct torque on the bolts. So
just tonight, I pull off both of the heads again and put them on the right
way - everything in the right order, torquing in 40 in. lb increments up

to
160 in. lbs. At any rate, I'm still in the same situation. Everything
spins, nothing sounds like it catches.

So here's what I'm thinking - first, I need to replace those head
gaskets and do it right, since I could have messed those up putting them

on
wrong and then taking them off. The second thing is that my flywheel key
could have been bent. I haven't checked this yet, since I haven't bought

a
flywheel strap wrench yet, but, as I understand, this could throw off the
timing, and I could be getting spark and compression, just not at the same
time. Other compression related issues, like bad valves or whatever, just
don't seem likely since the engine was running like a champ right before

the
connecting rod... exploded.

My questions to anyone who was able to endure this long post: am I
missing something simple? Do my current hunches seem probable? Any

advice
to a newbie who's hell-bent on fixing this himself? Also, feel free to

make
creative jabs at me for just torquing everything wrong, like calling me

"Mr.
Torquey" or something.

I apologize if this is posted to the wrong newsgroup - I saw a lot of
mower related questions in here.

TIA,

JvR