600HRS on 365 Mags...Rebuild heads, leave them alone?
12-01-2010, 07:25 PM
#12
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Location: Sarasota, FL
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I agree, those valves are time-bombs
I would atleast do the valve springs on it, it will be alot cheaper than when it drops a valve at 3500rpm.
But most will tell you at 250 hours on that eng. do the valvetrain then at 500 do the whole eng. rebuild.
Now everybody has to adjust to the way you use your boat, most people with 1075 Mercs. dont need to rebuild at 100 hours but if you race or only do poker runs and run up front you need to rebuild. Engines dont know hours they know RPM so if you are 6000rpm most of the time the engine wont last as many hours as at 3000 rpm.
My buddy had the same motors in his boat never ran hard took care of the boat with service stuff like oil and filters spark plugs but never even took the valve covers off. At almost 1000 hours he broke a valve spring took out the whole engine this was years ago but I think he spent like 6500 for a new long block and then 4000 to rebuild the other plus all the little thing he spent over 14k and missed a season of boating. Then sold the boat for 28k a year latter.
But most will tell you at 250 hours on that eng. do the valvetrain then at 500 do the whole eng. rebuild.
Now everybody has to adjust to the way you use your boat, most people with 1075 Mercs. dont need to rebuild at 100 hours but if you race or only do poker runs and run up front you need to rebuild. Engines dont know hours they know RPM so if you are 6000rpm most of the time the engine wont last as many hours as at 3000 rpm.
My buddy had the same motors in his boat never ran hard took care of the boat with service stuff like oil and filters spark plugs but never even took the valve covers off. At almost 1000 hours he broke a valve spring took out the whole engine this was years ago but I think he spent like 6500 for a new long block and then 4000 to rebuild the other plus all the little thing he spent over 14k and missed a season of boating. Then sold the boat for 28k a year latter.
12-02-2010, 07:56 AM
#14
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Location: Stafford Va.
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Pretty much the same motor (rebuild time wise) with a smaller cam and weaker bottom end. Anybody can do what they want but I have yet to save any money by cutting cost or not doing work that should be done.
