How to test run an engine on an engine stand ??

[HAS]

I would like to run my 1984 50HP 4cylinder MERCURY engine on an engine stand. I will connect the black (ground) cable to the engine block and the red (hot) cable to the battery side of the solenoid, if I jump across the solenoid will the engine run? My wiring diagram shows the orange (E) wire and the black (D) wire connected in the off position, the orange wire is the wire to the mercury switch. If I ground the wire to the mercury switch will it stop the engine? My engine wiring harness colors dont match the wiring diagram.
The wire to the mercury switch on my engine is black.



HAS

 

[CharlieB]

Re: How to test run an engine on an engine stand ??

Engines can be test run on a sturdy stand using a garden hose and flushing muffs. You must be sure that the stand is sturdy enough to withstand the rotational torque when the motor fires.

Grounding the wire to the mercury switch will kill the ignition, but beware, there is sufficient voltage that it WILL BITE if you are not careful.

It is not unusual for the prop to turn while in Neutral, but beware of any turning prop as starting a motor without the control box connected it is very easy to start in gear, a spinning prop will cause significant injury.

 

[HAS]

Re: How to test run an engine on an engine stand ??

CharlieB

Just had a successful 15 minute run on my homemade engine stand. I
thought that grounding the mercury switch wire would stop the engine, but
I always think is there anything else that needs to be done so I dont cause
any damage? If I had not decided to replace the damaged transom bracket,
I would not have removed the spark plugs and found that water was getting
in the no.2 and 4 cylinders.
It cost more in time and money then I thought it would but I was lucky
that I found it before any major damage. I now have a good used transom
bracket, a new exhaust plate, engine mounts, water pump and lower unit
seals, the carbs. and fuel pumps were overhauled last year along with new
fuel hose, primer, fuel filter and a 6gal.fuel tank. I hope the engine will be
OK for a while, now I will put some oil in the cylinders, run some anti freeze
through it and put it in the shed for the winter.
I thank you for the info. abont the exhaust plate, and I thank everyone
that was kind enough to help me.

THANK YOU...........HAS