Intermittent thumping sound when in reverse

[chris650]

Good morning everyone! I have an issue with my 1978 alpha one. When the throttle is in forward position, everything seems fine. But when I shift into reverse, im getting an intermittent clanking or thumping sound . Prop turns. Can anyone lead me in the right direction? IM thinking could be throttle cable, but am wanting to hear all possibilities.

thx

 

[achris]

Re: Intermittent thumping sound when in reverse

Get outside the boat and lift the drive, like the thrust of the prop would if it was in reverse... Can you feel any significant movement, particularly in the lower swivel pin? Or the trim ram anchor pins?

If so, there's your thumping noise.

Chris....
BTW, 1978 is an MC-1, not an Alpha...