'95 Crownline 5.7 Mercruiser Rebuild Part 7 -- Valve Stem Seals and Piston Ring Groove Cleaning

In Part 7 of this series, I show how to clean piston ring grooves on a 5.7 Mercruiser 350 SBC. The pistons are being reused so they have a bunch of debris built up behind the rings. I use a piston ring groove cleaning tool to remove this debris quick and easy. I also go over the head work that was done on this boat engine. The heads were trued up and reassembled with new valve stem seals. I went with positive style valve stem seals rather than umbrella style valve stem seals. These are a more modern and high performance design but the heads did require some machining to make the upgrade. I also installed new Z/28 valve springs.
To purchase the Lisle Ring Groove Cleaning Tool used in this video:
amzn.to/3JzqhCx
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#350Rebuild #Mercruiser #SBC

[@brianshangle3866]

What shop did you send the heads to?

[@605BOLT]

Just a local machine shop. L&L Machine Shop in Yankton SD.

[@brianshangle3866]

Do they have a contact you know of? Or the cost

[@605BOLT]

Their phone number is on Google. Really anyone can do the job. Nothing special about these heads compared to a Chevy truck of similar vintage. Installing new seals, machining the guides down and milling the head flat was like $300. Idk if that was a good price or a bad one but they are local and easy to work with and quick turnaround so that's what I did.

[@EEI605]

Very informative 👏

[@605BOLT]

For the grease monkeys.

[@PhillyDee215]

Cool 😎

[@605BOLT]

Thanks man. These are kind of boring vids I think but I hope they help someone if the get in a bind with a boat.

[@TheDjCarriere]

Thanks a lot for the video! What’s the manual that your using to look at the specs of the compression ring?

[@605BOLT]

All the ring end gaps are taken from the SELOC sterndrive service manual #3206 section 5-40. The height of the rings was measured with a caliper so I knew which rings to order. It is based on their thickness.

[@Gridlock71]

So what z28 valve springs?

[@605BOLT]

This is what I used.
www.speedwaymotors.com/Speedway-Racing-Valve-Springs-1-25-Inch-O-D-Set-16,88.html