More details needed.-----Where is this " fuel return line " on this motor ?

It appears there is a manual choke lever.----Try using that.----Or have an assistant hold choke closed.

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The lower shift rod must be fully screwed into the lower unit.----Propeller must be turned when shifting on dry land with motor not running.

How did it run for you last season ?-----If this motor sat for any length of time the carburetor may be gummed up.-----Is fuel fresh and mixed at 50:1 ?-----Does bulb on the hose go hard ?----Try...

Find your local Suzuki dealer.------They may have more experience fixing these motors.-----So what is your motor doing / not doing??

Serial # of this motor ?

Agreed---no fit.----Just rebuild the 1988 model 90 HP.-----With 4 new o/s pistons it will be good for many years.

Good eye.-----That red / orange goop should not come within 10' of a carburetor.------So this carburetor and the 2 others need some proper attention !!

Not possible to leak after proper repairs.-----Lots of used carburetors available for those.----Easy solution for you.

Switch the orange / striped wires and report test results.----Test spark that way as motor will not run.

It is still leaking so revisit your work.----Used factory repair parts on it ?

Inspect / repair / replace the float valve.

Is the tapered friction piece installed inside the tiller grip ?-----The rotation of the flywheel would rotate the magplate and SLOW the motor down would it not ?

Check for loose wristpin / rod bearing.-------Recheck location of the coils.-----Not sure how the rotation of flywheel can cause magplate to rotate and open the throttle.

Gasket behind the carburetor on the right way ?

Some will argue.-----There is something wrong with #4 cylinder.

But you say you have low compression on #4 cylinder.-----So something is wrong with piston , rings or cylinder wall on #4 I say.

Rotate the flywheel and see what #4 piston and rings look like.

I had a motor overheat once.-----I replaced entire stator and it worked great after that.