(UPDATE) My Vintage Briggs Flathead is getting low on Compression.

7394

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
Thanks Bert, I will get with them. That will save me from shaving the head a bit anyhow.

I have copper ones in my 45 Harley Flatty, that I Bored & Stroked to 59"....... Plus about every other mod I could think of.,.
 

bertsmobile1

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
Lanni is a really great person to deal with .
I send him over scans of obsecure gaskets and in a month a perfectly cut set arrives in the post.
Nothing has ever phased him.
HE will go to the effort of working out the maximum number of gaskets he can send without jumping up to the next post price bracket .
 
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7394

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
I think that is the place to get what I want.. Mine may not be so obsolete, but want copper about 1/2 the thickness of the oe ones..

Thanks again for the link to him..
 

7394

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
OK, getting more serious about this Engine, I was assuming it was just valves. Which shows what assuming gets me...

But did cold Compression Test today... Air cleaner off & throttle WFO.

Cold & Dry: 50 psi

Cold & Wet: 80 psi


By wet I mean I added a spoonful of oil in spark plug hole & re-tested.

Quite a Big difference. Rings seem to be getting weak as well.. I know I should have done my testing before I even started this thread. My bad..

Appreciate any & all input..
 
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tom3

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
Hope you don't see this on teardown. I found out the hard way that today's oil is not so good for old aluminum bore Briggs engines. Look close and see that the top where the rings still run is ok. Down lower the bore is not only scored but metal is actually being pulled off from the piston contact. Motor was running decent but using some oil.

briggsoldcylinder 2.jpg
 

7394

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
Yeoww, !!! Thanks for reply & that is shocking ! ! ! Never thought it "might" be aluminum bore. Mine uses "0" oil, but has lost power.

I've only run Castrol HD 30 in it. I'm not sure it is worth total rebuild. It was only a $149. mower when I bought it new in early 2006

It is model: 10T502 0457 E1 & Code: 06053152
 
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Scrubcadet10

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
PartsTree shows .020 rings available but not the piston, Std rings and piston are available $108 for a std ringset and piston.
 

tom3

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
I'd say you got your money's worth on that mower. If really damaged you might do a Surplus Center or Harbor Freight motor swap and get another 14 years?
 

7394

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
Tom- Why do you suspect oil did your damage shown ? I am extremely curious.

Wife hit a rock about 5 yrs ago on mine, crank got slightly bent, I got it straight as I could. I didn't think it would last this long after that.

I wouldn't mind re-powering it tho.. Or getting something w / Honda power.

Scrub- Appreciate the parts & prices, it is not worth a full rebuild.
 
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Scrubcadet10

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  • / (UPDATE) My Vintage Briggs Flathead is getting low on Compression.
Shortblock is available for $158 PN 398210 of course then you have to swap stuff over...
Might look at smallenginewharehouse.com, they have filters so you can search for specific crank lengths, diameter, HP, etc. and they'll show a compatible engine.
 
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