reverse knocking
 

took my boat out today and ran great except when i put it in reverse the motor would bang sometimes like it was slipping in and out of gear
anyone know what that could be
I have a 1988 150 mercury o.b it never did that before
is a loud bangging noise

Re: reverse knocking
 

I have a Merc. 200 Black Max.
Let me know what you find out.

Re: reverse knocking
 

Better have it looked at soon...sounds like one of those things that could cause more damage if not fixed ...could be a bad ''clutch-dog''... ::)...

Re: reverse knocking
 

that happened to a Mercury I had, the forward and reverse gears were fine but on the back of each gear are the clutch dogs, and in forward, just a bit over idle speed it sounded and felt like I was driving the boat over a bunch of rocks....not a good feeling. Step20, I hope it's the case, but , if it is, you already need a lower unit [ the reverse gear, that is]

Re: reverse knocking
 

I've got the same 88' merc 150. Drain your lower unit lube and look for metal particles / chunks. The bottom screw is magnetic so you may have some gunk stuck to it. When my lower went bad, I caught it before it "blew", that gear lube looked like it had glitter in it.

Good luck,

Airslot

Re: reverse knocking
 

It is possible the linkage is off and its not going FULLY into reverse?? They will knock in that situation.

Remember, think simple..FIRST. ;D

Re: reverse knocking
 

your right Stinkman, I would check the lower unit oil like Airslot said, then look at the linkages and cable adjustment for the reverse....hopefully the damage has not already been done

Re: reverse knocking
 

yep oil then linkage

Re: reverse knocking
 

ooops, sorry Step, I meant to say " I hope it's NOT the case"....good luck

Re: reverse knocking
 

how do you check the lincage
because i clean the motor this year[should have left it dirty] and it seemed hard going in reverse and then the banging

so i thought mabe i have to put grease somewhere but where

Re: reverse knocking
 

Hmmmm.....Hard shifting....maybe you've got a cable bound up. To check, pull the cowling off the motor and find where the shift cable hooks to the linkage. Remove the cable from the linkage. Now, try shifting from the helm and see how much effort is needed.

Now, for the more important part, operate the linkage by hand on the motor. Shift into both reverse and forward. When in gear the prop should spin about a half a revolution and then lock up.

If your lucky something is out of adjustment or you need a new cable.

Let us know,

Airslot

Re: reverse knocking
 

phester no problem i knew what you meant

Re: reverse knocking
 

i took off the cowl and greased all the points that neede to be greased, i started the motor with the ears on and put her in reverse and there was no knocking but it might only do it under a load
I dont know i want to put it in the lake by my house and try it before i go out again but the water is low in the lake so ill have to figure out something else

Re: reverse knocking
 

you definitely have to check it while you're under way. Do what Airslot said...drop it in gear, grab the prop w/ two hands and try to turn it..[make sure the key is off or pull your spark plug wires.......unlikely, but you don't want to start the motor by accident, then you'll have a REAL problem] if you can crank the prop around w/ "medium" effort it's probably the clutch dogs, Did you check the lower unit oil??? That should be step # 1. Keep us posted

Re: reverse knocking
 

i didnt check the lower unit oil yet but i will let you know how it turns out

Re: reverse knocking
 

i just put the engine in revese gear and turned the prop gut it only turns one way and makes a clicking sound
when i put the gear in forward it turns the other way and makes the same clicking sound
i thuink its good not the dog[am i right]

Re: reverse knocking
 

That sounds normal, if you have a big garbage can or similar you can fill with water and put a light load on and operate the the gear shift from the motor you might find like has been said that you are not getting a full engagement with the controls from the helm.

Re: reverse knocking
 

I like using my foot ::)