1992 Johnson 200 cyl heads

houndawg

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Anyone know how much the cyl heads on a<br />1992 johnson 200 can be cut? They are<br />casting #333809-4,just trying to up the<br />compression all cyl's but 1 has 85psi,<br />1 has 90psi.
 

rodbolt

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Re: 1992 Johnson 200 cyl heads

cut about 1/2 inch off them and you will be fine.<br /> actually no.<br /> your numbers look good<br /> dont cut the heads thats about where the numbers are supposed to be. try decarbing once or twice and run carbon gaurd for a few tanks.
 

DHPMARINE

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Re: 1992 Johnson 200 cyl heads

Well said rodbolt ! I actually limit it to 3/8 inch.<br />I wonder what the other 4 cylinders read?<br /><br />Let us know houndawg ! !<br /><br />DHP
 

houndawg

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Re: 1992 Johnson 200 cyl heads

5 of the cyl's have 85psi, 1 cyl has 90 psi.<br />I would have figured this engine should have<br />around 100psi,i have been a auto technican for<br />16 years & dont have not owned a boat until<br />recently but these compression numbers just <br />seemed very low to me,just looked like there <br />is alot of room for improvement there.
 

DHPMARINE

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Re: 1992 Johnson 200 cyl heads

houndawg,<br /><br />your readings are fine.I have never seen over 100 psi in these engines.It's the way they are.I think part of it is their slow cranking speed.<br />The good part is your readings are close to each other.<br />Do you have a specific problem with this motor?<br /><br />DHP
 

houndawg

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Re: 1992 Johnson 200 cyl heads

Not really,just a speed freak i guess..I have a<br />22 pitch renegade on this motor on a 20 foot <br />stratos bass boat,the engine turns 6200 at wot<br />at 66.8 gps mph,was just trying to get to 70..<br />Thought if i could get more on the bottom to<br />get it on plane i could go to a 23 pitch prop<br />& hopefully see around 6000 & 70 mph.
 

rodbolt

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Re: 1992 Johnson 200 cyl heads

hello<br /> there is a lot that can be done on that 200.repost and ask for Dhadley's attention. he seems to know a lot of speed tricks on the big loopers. I quit years ago. parts and diapers got to expensive :)
 

Dhadley

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Re: 1992 Johnson 200 cyl heads

Actually youve got a great combo there. Good baseline info. The Renegades are pretty good props. There are some others to try in this area.<br /><br />Do you have a jackplate? If so, manual or hydraulic? Is the gearcase stock?
 

Dhadley

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Re: 1992 Johnson 200 cyl heads

BTW -- the large exhaust port and port timing has a lot to do with the static compression numbers. As long as they're within 15 lbs youre good to go. Youre numbers are fine.
 

houndawg

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Re: 1992 Johnson 200 cyl heads

That sounds good,just seemed low to me,boat has<br />a manual jackplate,I have played with heights but need to do some measureing to see how high its setting,water pressure gauge still not working correctly so I dont want to go too high,thinking<br />of trying the boyseen reeds also,I have tried a <br />renegade 23 & 25 pitch on this boat but had <br />weight locations,23 pitch at that time turned<br />around 6200 rpm but I didnt have gps at that time,<br />25 pitch turned around 5500 but only went 63mph on<br />gps,but I have moved most of the weight to the back of the boat since then & gained 2 mph with the same raker prop.
 

houndawg

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Re: 1992 Johnson 200 cyl heads

I had meant to say I'm running a 22 raker,not a<br />renegade.
 
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