Bad new Carb? Other issue?

PTmowerMech

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Valves are operately correctly. Went ahead and pulled the head to do the gasket. Going to check the compression relief as well while I am already working on it. We’ll see what I find tomorrow....

You should see one of the valves bump a little, just before the compression stroke is at TDC, without having to open the sump.
 

repperl

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These engine are known for blowing head gaskets. If it were in my shop I would order a head gasket kit #794152 and replace the head gasket. First remove the valve cover and plug. Turn the engine over by hand and look to see if the valves are operating correctly. If they are remove the head, clean and replace the head gasket. Reinstall, torquing properly, and adjust the valves. Here is a service manual for the engine. https://docs.google.com/open?id=0B6NaqjIxWV1ybEN0LWo3azl6OUU. How you proceed is this is just my opinion.

Looks like the head has cracks in it...where can I get a new quality head? Worth replacing?
5.jpg

Also signs of cracking in the pan...something to worry about?
3.jpg
 

Scrubcadet10

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looks more like casting marks from the factory to my eye.
 

Rivets

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Right casting marks, nothing to worry about.
 

bertsmobile1

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And for the third time they are shrinkage fins
If you run your finger over them they are raised up off the surface not sunken down into the surface .
When the castings come out of the mould they have a tough skin on the outside but are still partially molten inside
As the last bits solidify it causes the whole casting to contract and those fins are the result from it getting smaller as it cools from 800 C to room temperature.
Bigger flatter ones are defects in the mould surface that have been polished out and strait ones are join lines because some of these moulds are better than 20 little bits clamped together .
It is all about driving down the cost price for the customer .
They could use moulds & a casting cycle that ends up producing smooth surfaced castings but that takes about 5 times longer per casting and halves the service life of the moulds so just about quadruples the cost of each casting.
Way back when people would pay a proper price they polished off all of these but again that takes a long time & pushes up the price .
Ask a plastic surgeon , pretty is not cheap .
 
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