21HP V-Twin Head Gasket Repair

StarTech

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Hey, that would make some good content... "Driving my racing mower until it throws a rod" Iol 😉
Well I had a go cart in the shop a few years ago that they putting it up on blocks to start it and rocking it off the blocks to ride it. They took a piece of field fence wire and had crippled the governor. It was the complaint that it in with the kid's father that it could be started without it taking off across the lawn.

The darn kid did it again but this time the governor part was not available. I have no idea has happen to it now.
 

GasGuzler

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Torque specs for this engine can be found online. Always look up correct specs for important parts such as head gaskets, and use a torque wrench. Gradually tightening head bolts in a pattern to correct torque is the right way. Reusing bolts will be no problem. Did you do a leak down test to determine bad head gaskets?
It had no oil in it and I believe it has a sticky valve, so heads will need to come off regardless. And once that happens, I’ll have to do head gaskets anyway.
 

Craftsman Garage

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Was it ran without oil or just leaked out over time? You might wanna crack the sump open and check for damage.
 

slomo

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No oil in a Briggs, she will be fine if you can get her to spin over. Little polish on the crank and such. Good to go.
 

GasGuzler

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Was it ran without oil or just leaked out over time? You might wanna crack the sump open and check for damage.
I’m not sure, the guy who I bought it from said it was in a storage unit he purchased. While spinning it over with the battery, one cylinder makes a loud popping sound through the intake and it feels like it’s pushing air back out through it. I don’t know if the oil was drained for while it was in the unit or if it was going to scrap.
 

Craftsman Garage

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You shouldn't have to rebuild it unless you have low compression on one side. It sounds like it could be a bent pushrod or valves need adjusted. A top end refresh is smart tho. Could only be a carb.
 
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