Exhaust Leak | Force 125

[Pjrogu]

My current issue with my 88 force 125 is that there is exhaust smoke coming from under the motor when running in the water. On muffs there is no issue as I guess there is not enough back pressure. I've read others on the forums say to check the exhaust boot for tears and mine does not appear to have any damage and is in failry decent shape. When the smoke come on it comes on from beneath the motor both fore and aft so that further leads me to believe it is the power head lower gasket that is the issue.

My question is, does this exhaust leak translate to power loss? I have trouble getting over 2500 rpm with a top speed of ~10mph. I previously believed it was due to ignition issues, but replacing the components did not seem to make difference. I am thinking that the increased back pressure is causing the smoke to come out of the gasket and not have fully "suck" out exhaust. Leading to exhaust in the cylinder during the power stroke and loss of power.

 

[The Force power]

Run it without the Cowl and see if it improves.
Check the compression on all cylinders
Check the Fuel system such as pump /hoses / vent

 

[jerryjerry05]

There might be an exhaust leak on the adaptor plate???
OR?? where the exhaust tube meets the lower housing, the gasket leaks?
Either way the repair consists of removing the block and repairing.
Run without the hood, as you motor along, look at the base of the block and see
if there's any exhaust leaking from the adaptor plate.
If it's leaking on the rear you might get away with covering the area with silicone.
That worked for me for a long time.

 

[Redbarron%%]

Wipe the area clean with some lacquer thinner to clean all of the oil residue so the RTV will stick.

 

[The Force power]

Also...check if the Spring clamp on the boot is tight/in place & boot properly inserted into the leg-cover.
Check the Exhaust-cover plate on the starter side if all bolts are tight & no exhaust fumes leak from between.
A little inspection mirror is nice tool to have for these tasks.
These inspections are to be done in the water & engine running in neutral