Carburetor issue?

[somethingabouttheloons]

I really have got to stop watching youtube videos.Thanks guys.

 

[somethingabouttheloons]

I've got a manual coming so hopefully that will detail a good procedure.

 

[somethingabouttheloons]

I am seeing conflicting posts regarding the section on my cam that is stamped TOP
It appears most say to set .020 with rub block aligned with key. Is that actually the high of the cam?
Eyeballing the cam it looks too me that the high is where it's stamped.I am going through and
doing compression check, spark gap and timming today.The manual I just got just says to align
the rubbing block with the high of cam and unfortunately for this rookie doesn't have a nice picture showing
this location on the cam.

 

[somethingabouttheloons]

Also, I plan to use the method I found on the forum using a meter and wire lead to time
the points.

 

[oldboat1]

You can see the high point of the cam by slowly turning the prop slowly with your foot (counterclockwise for the 3) -- watch the points to see where the rub arm is when they open the widest. Take the plugs out.

 

[somethingabouttheloons]

thank you oldboat1

 

[somethingabouttheloons]

Bad news today, I finally got a compression checker and I'm pretty sure I used it correctly but
cannot get more than 15psi in top or bottom! Guess I've got a boat anchor now!!

 

[somethingabouttheloons]

Guess it's time to check gaskets and rings

 

[oldboat1]

just to be sure -- need a screw-in style tester. Make sure the O-ring is complete and in place so it will seal. Hand tighten into plug hole taking care not to cross thread (remove both plugs for testing). Put the gauge someplace in view, and pull the motor over three or four times until the needle stops moving. Record, and move to the next cylinder.

 

[somethingabouttheloons]

Well here is what she looks like, I poked each ring and they all had spring action.
Seems like allot of carbon build up but not experienced with these .Don't see any
real breaks in the gasket. Definitely
old gaskets though.

 

[oldboat1]

Piston appears to be banged up, as if the plug reach was too long. Appears to be a lot of carbon build up. Plug is J4C -- might try some spray carb cleaner to clean up, resurface head and replace gasket -- then retest.

 

[somethingabouttheloons]

I was really expecting too see something very obvious with the readings I'm getting.

 

[somethingabouttheloons]

That's the type tester I have oldboat1. Pretty much did exactly as you described

 

[somethingabouttheloons]

Oh and JC4 are what were in it when I got it. I will try what you suggest.Thanks

 

[somethingabouttheloons]

Should I install head and exhaust gaskets dry?

 

[somethingabouttheloons]

I installed new gasket and got the exact same readings of 15 psi.
Toast I guess.

 

[racerone]

Well, ----I think your gauge is toast.

 

[somethingabouttheloons]

I have a great running Merc 2.5 that I'm gonna use the same gauge to check it's compression.
.

 

[somethingabouttheloons]

Got a different gauge and low and behold I get readings of 70 psi on both cylinders
I know that must still on the low side.My 2.5 readings were just over 100 psi each.
Need to check my spark. Is it supposed to be at least 7/16

 

[racerone]

No----5/16" is plenty on those ultra simple magnetos.