2002 Tige 21i Type R 5.7 SKI carb engine knocking sound.

[Ulrik]

I have a video of one side and pictures of two port from the other side. I have cleaned it all so cant take new pictures.

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[Ulrik]

I want to buy all new valves because a mechanic told me some of my old exhaust valves was getting too thin. How do I know if I get the right size and quality?
Edited: When i look up my engine serial number i get these dimensions. Exhaust HEAD 1.500", LENGTH 4.923", STEM .3410" Intake Head 1.940, Lgth. 4.879, Stem .3410
Still I cant seem to find many with these exact dimensions :/ Any suggestions please
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Block cleaned.
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[wired1236]

Have you tales to these guys? www.marinepartsexpress.com

I know you're not in the US but...

[Ulrik]

Mercruiser Part number: 824317 1 and 809992 50$ x 16 VALVES is this for real? There must be another solution either aftermark ones or clean and reuse the old

[boatwakes]

Yes there is, we have everything you need but who is prepping and assembling the heads? Have you had the exhaust seats in the heads replaced yet? What, if any, machine work has been done? Please store the crankshaft standing up so it doesn't bend.

[Ulrik]

I have been getting prices from machineshops on testing + prepping + new valves in the two heads and test + hone cylinders + prep the block. But not on changing exhaust seats? Is this really necessary cant i just clean it good.
The cheapest price so far was 1250$. Right now i'm wondering if I should just save the money and do the things i can myself and reassembly it again. Then I can buy a rebuild engine if this one explode

[boatwakes]

The exhaust seats are the reason for the failure. As the sea water starts to pit and corrode the seats and the valves, they lose their ability to seal against the valve face and your compression stays low and the same thing happens again. $1250 for all that is actually a pretty good deal. You can do whatever you would like, ask questions along the way and I'll answer them. There's a motto we follow and my employees live by it too; "We only do things one way and can always explain why if you ever have a question." I'm here to help.

[Ulrik]

Well I'm going to try and do it all myself with help of a mechanic friend or two. I got it all cleaned up pretty good already, gonna give it a clean again in a few days before the reassembly starts. I know its not the ideal solution but i'm fine with it

[Ulrik]

I finally finished the partial rebuild of my engine. Compression is back on all cylinders and i'm happy again

[IDBoating]

Nice purr at the end. An accomplishment to be proud of! Great work!

[Stingreye]

I am always impressed when an owner tackles a job like this!

[boatwakes]

Nice job dude, sounds good!