73 chrysler 857he low rpm eont go over 4 mph

rotik1

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May 24, 2015
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We recently bought a 1973 Chrysler 857he . i have personally never worked on a boat. We got it i. The wter this weekend nd we could not get it to go. We adjust carbs did nothing. Any ideas? It does bogg out or die seems to be getting good fuel. Hope some one can help
 

mfkadz

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May 26, 2015
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What do you mean by could not get it to go? Would not start. Ran rough, slow speed at wide open throttle? When does it bog down?

Need input...

Mike
 

rotik1

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Ok in neutral rpms go to 2000 when we put it in foward it drops to 1100. And wont go no faster than 4mph.
 

mfkadz

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May 26, 2015
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Sounds like a cylinder or two are out. I would pull a plug wire, run the motor to see if it runs differently. Do that for each cylinder. I expect there are one or two cylinders not working. You will know which when you pull a plug wire and nothing changes. Do the pull and plug with the motor off to avoid a jolt.

From there you will need to determine if it's fuel or fire.

Have you pulled the plugs to check for fowling and proper gap?

Mike
 

rotik1

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We just replace them before we took it ro rhe lake. But we will try that.
 

firstboat2015

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I had a motor that was doing this as well. The spark plugs would be a good place to start. Something else you might want to do is flush your carberator. That seemed to solve one of the issues I had with my new used motor.

It's a different size and manufacturer but it's worth a try.
 

rotik1

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Copy. Well we just did a compression test it good. But we started to clean the 3 carbs. Two have been dirry so far . so hope fully that helps
 

mfkadz

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May 26, 2015
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If it had been sitting that should help.

I would remove the bowl from each carb and flush the carb good with cleaner. All the holes as there are a few passages. Make sure the float sits level when full. No tipping. You should be able to remove the idle screw and hi speed jets also. Flush both those out too.

Best bet is to get the kits and rebuild each of them. There should be clean out caps that can be removed for cleaning the passages. And then replacements should be in the kit.

mike
 
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