Why does my enfield outdrive knock severely when under load. The engine is fine.?

Question

my boat has an enfield outdrive that works ok when on tickover, but knocks violently when driven under load. I have eliminated possible engine problems The outdrive seems fine when bench tested and the drive shaft and bearing seem ok. Help please, fishing starts soon.

Answer 1

Timing may be off...preignition detonation. Poor fuel quality?

Answer 2

The 90 degree crown gear is climbing over itself due to too much play and rocking the mainshaft, it needs thicker shims.

If it gets too loose it can shatter the bearing housings or snap the mainshaft.

Answer 3

It's not fine, sounds like a big end.  Don't take it out unless fixed properly, or you may not make it back.

Answer 4

Thats a poser. I have found a forum which appears to be dedicated to Enfield outdrives that may be of help, it`s ybw.com

Hope this helps

Good fishing

Answer 5

The universal joints between the engine and the leg need either greasing or replacing, if you have never greased them then they will definately need replacing.

You have to remove the outdrive leg to get to them, on the Mercruiser legs this is fairly easy, the Enfield design is very similar, but don't do it with the boat in the water.

Answer 6

FUEL QUALITY?

OR THE MIX OF TWO STROKE OIL