Oil leaking from intake manifold B&S 21R707-0039-G1

jmandawg

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Long story short, i bought this off craigslist, it was missing intake manifold, carb, and air intake manifold and filter. Guy said it ran fine, and I just needed to replace those parts. So here i am 2 weeks later, all parts replaced, i start it up and and it runs, but there oil dripping out of the intake manifold (the one between the carb and the engine block). See pics attached. The blue arrows are where it's leaking from.

Does this mean the cylinder gasket is blown?

Thanks.
 

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ILENGINE

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If there is oil dripping out of there then it looks like the O ring is leaking. the question is where is the oil coming from. Either from the cylinder that is blowing back due to the compression release at startup, or the oil level is too high by either being overfilled, or mixed with gas.
 

jmandawg

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Thanks for the reply, The engine oil is not overfilled. The guy i bought it from also drilled into the engine to try and jerry-rig up an old carb (see pic) hopefully he didn't go too deep..
I need to bypass the seat saftely switch so i can get a better look at it tomorrow. Sorry I'm a total noob to riding mowers.
 

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ILENGINE

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Need to check that. Could of drilled into the push rod cavity. Wouldn't take much to make a mess.
 

Hammermechanicman

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Pull the crankcase breather hose off one end and run the engine. If it blows oil out with a lot of vapor good bet head gasket blown between cylinder and pushrod area. This engine is is pretty famous for blowing head gaskets. If you replace it retorque the head bolt after a few heat cycles.
 

bertsmobile1

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Adding to Hammers reply.
I have a large flat oil stone that I use to stone the cylinder before refitting the head.
The head gats a lap on a sheet of 800 wet & dry on a sheet of glass.
Those engines go hollow between the bore & the push rod tunnel.
They really need anothe bolt inside the tunnel.
 

jmandawg

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So bad news, i was able to get a better look at it today, and the oil is blowing out of the hole the guy drilled into the engine to jerry-rig the carb. The worst part is he drilled right in between the head and the engine block (right where the gasket is).

Is there anything i can do or is the engine toast?
 

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Rivets

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Engine is toast, only thing you can do is go after the guy on Craig’s list with the biggest hammer in your toolbox.
 

StarTech

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A real intelligent guy wasn't he.

It might take someone Tig welding it and machining both the head and block back to flat. There might be some redneck repair ideas offered too.
 

Hammermechanicman

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What a D-bag. I would go back on the guy and show him the hole and ask how it ran just fine. Amazing how many unscrupulous retards inhabit the planet.
 
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