McCulloch 7.5 and Chrysler 8HP

[leathwood]

Hi im new to boating, i just got a 12 foot aluminum boat that came with 2 motors.
The McCulloch 7.5 turns over and feels like it has compression but im not getting any spark.
I am having trouble finding any info on this motor. Serial # 65300750-C

I also have a Chrysler 8hp that i am waiting on parts for(its a 1971 i believe) the gear that turns the motor over is broken.

if anyone has any info on either of these motors that would be awesome, as I've never had a boat before.
thanks
Dylan

 

[leathwood]

[No message]

 

[RCO]

The Chrysler is actually a pretty decent motor. A lot of parts are still available from Mercury dealers (Chrysler was bought out by Force, who was bought out by Mercury), and some of the more common parts are available aftermarket. The McCulloch low profile motors had troublesome water pumps, and parts are mostly unavailable. They are a bear to work on also.

 

[F_R]

Your McCulloch is a 1965 model. google laingsoutboards for possible parts (both motors)

 

[leathwood]

Hey thanks for the reply guys. Is there any chance anyone would know where i could get a technicians manual for either of these motors? I am not used to gas engines and this is my first time ever looking at a boat motor.
Thanks
Dylan

 

[flyingscott]

I would like to know why the 7.5 low profile mcculloch waterpumps are troublesome. The only thing I would say about the McCulloch is make sure which set of points you have. There was a change around 1965 and the later points are hard to find. I run several of the 7.5 low profile motors and they have been very reliable motors for me. Your mcculloch has the more desireable lower unit. Does that have the silver kill switch in the front if so make sure it is not shorted. Waterpumps and gaskets are avialable new for the mcculloch.

 

[leathwood]

It does not have a kill switch on it. I took the fly wheel off to look underneath.... My guess is the points are bad. Is there any easy way to tell which ones i have?
thanks

 

[flyingscott]

Put up a pic of the magneto. I would clean them up and reset them to .020. I would also clean up all the connections. Those are very good magnetos and usually need to just be cleaned to work again.

 

[leathwood]

the condensers(i believe they are called) had 0.8 resistance(they were both the same so im guessing they are good. Im trying to find out how to test the coils and trying to find out if they are adjustable. im confused because i have absolutely no spark on this motor

 

[flyingscott]

Those are the old style points available new. The coils on those motors do not often fail. They are a much better quality than those used by Evinrude and Mercury in those yrs. Clean them up and see if it runs. Carb kits are available for that motor also. But make sure it at least fires and runs before buying anything. To replace the fuel pump diaphragm the power head must be removed from the motor. Not an easy thing to do. I would choose between the 2 motors as to which one will be cheaper to make run.

 

[leathwood]

What is the powerhead exactly? I have lots of tools.... the chrysler has no spark but if i turn the motor over i can feel a spark while holding a screwdriver in the plug... it just is not making spark on a good plug... i think its weak. i will try cleaning up and re-setting the points tomorrow and see if i can get this one sparking.
Thanks for the help

 

[flyingscott]

The powerhead is the engine itself.

 

[leathwood]

Hey so I have a bad coil. The secondary I beliven from the plug wire to the coil. On the top cylinder. Are these still available ?
thanks

 

[F_R]

A bad coil will not affect both cylinders. Make sure the problem isn't in the spark plug boot.
0.8 resistance in the condensers makes no sense at all. Recheck your work
Those points look scungy when I enlarge the picture. Take them apart and polish each contact individually.

 

[leathwood]

i cleaned the points set them to .020. i have spark on the lower cylinder the top cylinder has no spark. i had resistance from the good coil to the plug boot. the other coil is showing its not connected. i checked to make sure the plug boot was connected to the wire coming right out of the coil, and it is good. i have seen some coils online but they do not look the same.
thanks
dylan

 

[flyingscott]

You can buy a whole magneto assembly off of ebay for cheap.