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Timing marks

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davebonacker1
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Timing marks

Post by davebonacker1 » Thu May 30, 2019 9:08 am

I recently did a 283 to 350 upgrade. The 350 I started with were new 350 long blocks that someone else started to convert and lost interest. I have fintshed the conversion and have the motors running. The problemI I am having is in using a timing light I can not find the timing mark. When I advance the light to 30 degrees the mark comes into site. The starboard engine has an L stamped by the timing mark. Could it be possible the engines have the the wrong flywheels on them. What degree setting should I use to check the timing? Thanks Dave

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Bilge Rat
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Re: Timing marks

Post by Bilge Rat » Fri May 31, 2019 7:27 am

How do they run and start? Any backfire? If the timing is that severely off I would think there'd be obvious issues. Might be the flywheel is incorrect or miss-marked. Might be what someone thought was number one top dead center isn't because the flywheel is forward not aft and the cylinder numbers are different? You may have to confirm that number one cylinder is really top dead center and the mark is at the pointer.
1966 Lyman Cruisette 25 foot "Serenity Now!"
1953 Chris Craft Sportsman 22 foot "Summerwind"

jfrprops
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Re: Timing marks

Post by jfrprops » Fri May 31, 2019 8:48 am

huuummm…..did rotation figure into this timing …??

John in Va.
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jim g
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Re: Timing marks

Post by jim g » Sun Jun 02, 2019 7:12 am

davebonacker1 wrote:
Thu May 30, 2019 9:08 am
The starboard engine has an L stamped by the timing mark. Could it be possible the engines have the the wrong flywheels on them. What degree setting should I use to check the timing? Thanks Dave
The L means left hand. So I would guess you have the flywheels on the wrong engines.

If that is the case you will need to bring the engines up to top dead center and make a mark on them for timing.

What distributors are you using. If they are original's to the Chris Craft engines. I can probably give you the measurement for the timing mark after TDC and the max advance at the RPM it happens at. Which you can set timing that way if you have a timing light that advance's.

davebonacker1
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Re: Timing marks

Post by davebonacker1 » Sun Jun 02, 2019 1:59 pm

Switch flywheels is what I was thinking. I am using Deleo-Remy 1110630. The engines start and sound good but will not run on the factory timing mark. I have an adjustable timing light, when the factory timing mark is insight it is reading 30 degrees at 600rpm. I was wondering what the degree difference between the standard and opposite rotation motors would be. Would like to be able to use the mark on flywheel with my variable degree timing light. Seems like it would hard to find exact top dead center at this point. Thanks for the help.

davebonacker1
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Re: Timing marks

Post by davebonacker1 » Wed Jun 05, 2019 10:22 pm

Pretty sure the flywheels are on the on the wrong engines. They start on sound good,but not sure how to get a accurate timing. When I have the engine idling at 500 rpm my adjustable timing light is reading 25 degrees. Can rev engine and get 40 degrees . I know the advance isn’t that high just what it takes to read factory mark. Any suggestions on what to use as base mark, or should I just tune by ear. Thanks Dave

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