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Timming advance question 1976 Evinrude 75643D 75hp Outboard

See the 3 plates / housings that make up the exhaust manifold on the port side of the block. ????------Take them off and look for bad gaskets / warpage there.-----A leak there can be a major issue.----Lots of those motors have developed water leaks in there.----Could be a hole in the crankcase too from a piece broken off a piston.
 
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Ya need to replace the #2 reed box if ya want it to stop spitting fuel.

Thanks for that added thought. Thinking and hoping now the absent of the water will allow the reed to still work. Water in the import side was a compounded leverage weight against the reed to open when it should be closed. Now the water is gone maybe its ok. You may be right it did affect it with strong pressure but not by full head pressure. That reed is a harden tempered spring steel. I’m leaning it’s more likely to break than bend. You do have me worried if it’s fatigued and bent a little open or broke. Thanks for this thought. The more I think about it the more I worry and will be looking at it soon. The reed may need to be replaced.


Any thoughts on installing a new head gasket? I installed it text book tight and started from middle out. Why it didn’t seal? The head was dished but I think it should have still worked. Apparently I was wrong.

The block is straight. The head only is dished Check post #51 video
 
See the 3 plates / housings that make up the exhaust manifold on the port side of the block. ????------Take them off and look for bad gaskets / warpage there.-----A leak there can be a major issue.----Lots of those motors have developed water leaks in there.----Could be a hole in the crankcase too from a piece broken off a piston.


The head had clear marks around the center cylinder wear the water entered. Thanks for the heads upon about the port exhaust plates. I have no evidence of pieces broken off issues yet.
 
See the 3 plates / housings that make up the exhaust manifold on the port side of the block. ????------Take them off and look for bad gaskets / warpage there.-----A leak there can be a major issue.----Lots of those motors have developed water leaks in there.----Could be a hole in the crankcase too from a piece broken off a piston.

[COLOR=rgba(0, 0, 0, 0.87)]Shows were water came in. Head was never shaved enough low in the center[/COLOR]

https://youtu.be/BOCQKs7b16A
 
See the 3 plates / housings that make up the exhaust manifold on the port side of the block. ????------Take them off and look for bad gaskets / warpage there.-----A leak there can be a major issue.----Lots of those motors have developed water leaks in there.----Could be a hole in the crankcase too from a piece broken off a piston.

Sanding with 120 to level head Thanks Racerone

https://youtu.be/pLzas6HJU5k
 
Every outboard cylinder head ( lots of them ) I have looked at has been warped like that.----No surprise at all.----Use a piece of glass and emery paper / valve grinding compound the correct this.

Cleaning it up leveling thanks Racerone

Thank You
 
See the 3 plates / housings that make up the exhaust manifold on the port side of the block. ????------Take them off and look for bad gaskets / warpage there.-----A leak there can be a major issue.----Lots of those motors have developed water leaks in there.----Could be a hole in the crankcase too from a piece broken off a piston.

Stay with me Racerone the bolts are falling off the 3 plates. After new head gasket that showed exhaust marks we find your other advice with these plates. please advise.

https://youtu.be/pTSA4bxkTcA
 
Do you even own a torque wrench? O,thats right,no service manual dont need torque wench.


https://youtu.be/UAvZMihxF6w I have 3 torque wrenches My old dial torque wrench I had when I was a kid. I have an inch pound ratchet from 0-240 inch LB, And I have another bigger ratchet from 20 LB;s to I think 150 or 200 foot LBs’
I do feel I could have done better with this rebuild. I learned where to pay special attention. I went hard to fix it right this second time. I torqued everything by the book the first time with a marine sealer not Loctite on the bolts.
This time I torque by the book and then went back over everything and gave it my own feel to tighten. I used Loctite on the bolts.

I want to thank all who helped on this post to get my motor running. Again Thanks


[URL="https://youtu.be/UAvZMihxF6w"]https://youtu.be/UAvZMihxF6w


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