200hp Mariner/ Power Loss

[Fred Reed]

90 model 2.4 , Carbs

Lost 1000 rpms on top end. Motor starts and runs but lacks the normal torgue and power.
Weak hole shot and top speed is off 10 mph.
The problem occured all of a sudden. Power loss seems like a plug is fouled. Plugs are oily but this seems normal for my motor.
.Checked out the plug firing / good
.Changed out Plugs
.Fuel is fresh and filter is clean.
Need help please.

[blackvector]

I would check your compression on all cylinders if thats fine I bet you lost spark on one or more cylinders. Check with a spark checker, DVA tester, or timing light.