Evinrude 18HP 1960 low power

[fleetwin]

OK, so the reeds look fine, and you didn’t mess with them.  The engine ran OK during your initial run, so it seems as though you had the intake gaskets properly oriented as well.  I’m not quite sure just where the fuel leak is you decribe, almost seems like you are talking about a leak where the fuel hose connects to the carburetor.  If so, replacing the rubber fuel line usually solves this issue.  Or, for now, just cut a little off the fuel line so it fits more securely onto the carburetor fule inlet nipple.

Many of these ebay sellers are less than honest, and want you to assume you are buying OEM parts, when you are not.    The engine ran OK for awhile, and then did not.  So, what changed?  Are you sure this engine is running on two cylinders?  You mention it is low on power, does it run OK/properly at low speeds?  When it misbehaves at high speeds, does it run smoothly (except for the lack of power), or does it sound rich?  If it sounds rich, then perhaps the carb is at fault, or perhaps the fuel pump diaphragm is leaking flooding one cylinder.  If the engine sounds relatively smooth at high throttle settings (just low on power), it would seem as though it is running on one cylinder and probably has an ignition issue.  I would run the engine again using those inexpensive inline neon spark testers to monitor spark while the engine is running.

But again, let’s not overlook the simple stuff.  Perhaps one of you plugs is fouled/bad, even though it might be new.  Perhaps the throttle linkage is messed up preventing the carb from opening fully, or ignition from advancing properly…

[jeff-register]

Another way to check the reed valves is hold the plate up to a light & then you can see how much light comes thru the gap on the seated reed plate & reeds.  Should be iniform light thru all the reeds & figure fuel / oil mix would seal the reed to the plate. I too think your first rebuild kit being faulty. Brings to mind I trouble shot a windshield wiper motor that was a rebuild & it wouldn’t turn off. Did a inspection to find one wire wasn’t soldered in place. Now I never assume the new parts are accurate & comare to parts are removed. Also inspect the neeedle & seat with a magnifier glass for sloppy machining. I have repaired the seating surface using valve seating compound, not the best fix but I couldn’t find a replacement part. Good luck with your project & look at everything closely for fit & finish.

What condition does your spark plugs look like? Fouled plugs tell a good report of events in the combestion chambers, one fouled or different that the other?

[salnaes]

Hi again. Sorry for the long delay. Problem solved. It was only wrong adjustments of the high speed and low speed needles. So when I got it right, my Evinrude 18HP Fastwin 1960 performed excellent.  My 10 feet boat from 1965 made around 30 knots.  So now I’m happy.

[labrador-guy]

sutterhome wrote:

DID THE BRASS NEEDLE SEAT FIT?

The kit I ordered had some bad treads on the needle seat.  I ran a tap over it and it works OK.   Something for you to check.  OMC kits may come from china also.

dale

[crosbyman]

those  cheap kit…. needle   seats  never fit   🙁       what did you retap…. the carb body ??  with what size  tap thread  ??

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[crosbyman]

happy ending… the best   thanks for feedback  !

 

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[fleetwin]

Glad it is resolved, and was a simple fix

[Fastwin18]

labrador-guy wrote:

sutterhome wrote:

DID THE BRASS NEEDLE SEAT FIT?

The kit I ordered had some bad treads on the needle seat.  I ran a tap over it and it works OK.   Something for you to check.  OMC kits may come from china also.

dale

Same here. I purchased a set for my Fastwin 18 and the seat didn’t fit. I tapped new threads on the brass seat (not the carb).
Purchased another setfor my QD19 which fitted perfectly. Now today I overhauled my AD10 carb, and again the seat didn’t fit.

Apparently they either apply different threads, or have different factories producing these kits.

[crosbyman]

so  for referrence  what size  tap was used on the seat

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[Fastwin18]

I don’t remember but I will have a look tomorrow, the carb is still in pieces.

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