help...just splashed resto project and have dive issues!

[solar7647]

Ok, I just splashed my project for the first time today. The engine is a 3.7L Merc that was was rebuilt with a new long block and is running awesome. Its super smooth in neutral but when the boat is put into drive it develops a loud knock like metal on metal coming from the rear of the engine. I cant figure it out, its only when under load. The knock is also followed by a bogg in power as rpms increase. When the motor is not in drive its smooth all through rpm range.

Any ideas

 

[solar7647]

Re: help...just splashed resto project and have dive issues!

oh and yes the engine was aligned with the proper tool and slid in super smooth when it was installed.

 

[cr2k]

Re: help...just splashed resto project and have dive issues!

How was your gimbal bearing? U-joints?

 

[solar7647]

Re: help...just splashed resto project and have dive issues!

Well just to close this thread up, I found the issue. The drive gear on the disributor has a flat spot on it that was causeing it to stop rotating and causeing the #4 piston to miss fire. It would run fine at idle with a small miss fire I thought was do to a dirty plug, but when it would be put under load it really miss. so i have a new gear on the way. Lesson learnedm should have inspected it better when it was put in. I know the new cam gear didnt cause the damage because there was no sign of it on it at all. so the wait continues.