loss of rpm - Another question for Dhadley

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Hooty

Rear Admiral
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Oct 2, 2001
Messages
4,496
Re: loss of rpm - Another question for Dhadley

Test it on the trailer. Put just enough boat in the water to submerge the cav plate, be sure it's tied good and the bow is against the stop. Power up slow and it'll be fine. Some guys use a old cutdown prop but I use whatever happens to be on it.<br /><br />c/6<br />Hooty
 
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codkiller

Seaman
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Apr 25, 2004
Messages
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Re: loss of rpm - Another question for Dhadley

RetNav, The coils never came in on Friday so looks like I will have to test out the boat this coming weekend.
 
R

RetNav

Senior Chief Petty Officer
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Aug 14, 2003
Messages
758
Re: loss of rpm - Another question for Dhadley

codkiller, thanks for keeping us updated. <br /><br />I went out this weekend and just got back from the dealer informing him of the results and his response was "I can't believe that motor won't turn any more than that!" Sort of burns my a$$.
 
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codkiller

Seaman
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Apr 25, 2004
Messages
54
Re: loss of rpm - Another question for Dhadley

RetNav, Installed the new coils and took the boat on the lake yesterday. The motor runs great but still only get 5200 rpm max. Don't know what else to check. The whole ignition system is new, timming is on , compression is 90 psi on all six.<br /><br />anybody?
 
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Daniel Beckman

Petty Officer 2nd Class
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Jul 8, 2002
Messages
171
Re: loss of rpm - Another question for Dhadley

Sorry, maybe a dumb quest is the engine mounted exact the same as before?
 
C

codkiller

Seaman
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Apr 25, 2004
Messages
54
Re: loss of rpm - Another question for Dhadley

Dhadley, I used the boat on the lake in a three day salmon fishing derby. The motor ran great. Started right up, good idle and great acceleration (still only getting 5200 rpm max after replacing all the coils). What has me concerned is I am getting a lot of soot build-up on the transom. It does not seem to be smoking and oil consumption seems normal. I pulled the plugs to inspect and they look normal to me. I never had this problem before the rebuild.<br /><br />Any ideas?
 
D

Dhadley

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Re: loss of rpm - Another question for Dhadley

When the motor was rebuilt did they rejet the carbs?
 
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Dhadley

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Re: loss of rpm - Another question for Dhadley

Actually, I went back and read your first post that says you got 5500 in the beginning and it slowly declined to 5100. That may not have been due to poor compression. <br /><br />Its natural for a boat to get heavier with age. Trapped water, added gear, hull distorition (certian kinds of trailers) -- things like that. Rebuilding your prop could account for some also. <br /><br />So if we use 5100 as the baseline, youre 100 above that now. If you can use all of your trim range now, raise the motor up a hole and see what kind of gains you see.
 
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codkiller

Seaman
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Re: loss of rpm - Another question for Dhadley

I'm not sure if they did. Boysen reeds were installed to replace the stock reeds. I heard that you need to rejet the carbs after installing Boysen reeds and I would think that they would know that. I can not get any info from the rebuilder so I am gonna have to determine myself if in fact they were rejetted. Would you happen to know what the stock jets would be for this outboard (model # E200TXES serial# G02496101) and what jet would need to be installed after changing to Boysen reeds. How would I know what jet is installed in the carbs?
 
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Dhadley

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Re: loss of rpm - Another question for Dhadley

The only jets involved with the Boyesens should be the idle jets. If the motor doesnt "sneeze" at idle you dont have to worry about it anyway.
 
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codkiller

Seaman
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Messages
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Re: loss of rpm - Another question for Dhadley

No sneezeing what so ever. So what do you think would be causing the soot build up on the transom? Is this something to concerned about?
 
D

Dhadley

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16,978
Re: loss of rpm - Another question for Dhadley

Soot is unburned fuel. Some causes are; the carbs are not jetted right, the floats are not set right, there is a fuel leak, a weak ignition component, improper timing (very unlikely but possible) -- things like that.
 
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codkiller

Seaman
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Messages
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Re: loss of rpm - Another question for Dhadley

Ok the ignition system has all been replaced with all new componets so I guess the problem is fuel related. Do you know what size jets should be installed in the carbs? I will check the size tonight as well as the float level.
 
D

Dhadley

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Re: loss of rpm - Another question for Dhadley

The jets depend on what the carbs came off of. There were different calibrations for different years and things like airbox configurations (using the inner airbox or not), air nozzle sizes, throttle body sizes, venturi size and more.
 
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codkiller

Seaman
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Apr 25, 2004
Messages
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Re: loss of rpm - Another question for Dhadley

This may be a stupid question but I have to ask. I always used Evinrude / Johnson TC-W3 2 cycle oil, when I went to purchace oil from my dealer all he had was Evinrude / Johnson XD25.<br />Would this oil burn different than TC-W3?
 
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