XR2 Lower Unit Problem

[SlalomSkier01]

Hi, I have a 1985 Mercury 150hp XR2. Everything is stock with no modifications. I put it in the water for the first time this and instantly had problems putting it into forward or reverse. I have had the problem before, but have been able to fix it in the past. After taking the cowling off I adjusted the little brass nut of the gear shift cable across the whole range of adjustment twice and have not been able to make it work properly. The place I have settled on has allowed me to shift into reverse with no problems, I can also shift into forwards with no problem at an idle. When the motor is in forwards everything is good until I accelerate and there is 2 LOUD chunking noises as if not properly in gear. Once I have shifted in to forward, then accelerate and it makes the 2 chunking noises everything is good. I can bring the throttle down to an idle and as long as it never comes out of gear it will not make any chunking noises no matter how much i accelerate. As soon as I take it out of gear and put it back in forwards and try to accelerate it will make the 2 chunking noises again.

As I said before I have gone through the complete range of adjustment on the cable end at the motor with no success. Even If i adjust it all the one way I can not get the forward gear to work properly. Is there any adjustment in the actual lower unit itself? What does this problem sound like to you guys? Thanks,

[flabum1017]

Sounds like a bad shift cable.... disconnect the cable at the motor and shift it by hand at the motor. If it shifts nice and easy at the motor then you probably have a bad shift cable. They usually get rusted and split open somewhere....... usually at a bend or at a chaff point

[KeninSC]

Don't forget to check if the bearing retaining nut has backed out or strippped out. This is a preload case...not the strongest out there.

[SlalomSkier01]

Don't forget to check if the bearing retaining nut has backed out or strippped out. This is a preload case...not the strongest out there.

Thank you for the input, but what is the bearing retaining nut? I am assuming that once the prop is off and you use that special tool to pull all the guts out of the bullet shaped portion of the lower unit casing I'll find a nut against a bearing that holds everything together in there? Is there anything I should know about taking that part of the lower unit apart? Are there seals and such that should be replaced when I am in there? Ive searched but can not find a guide to taking the lower unit apart of google or this forum, does any one know where I might find one that I may have missed? Thanks, also I have checked the cable and everything seems to be good, no cracks or rust spots and functions smoothly.

Thanks for all the replies

[KeninSC]

The piece that you use the "special" tool to tighten and remove is the retainer. If this is your problem you should be able to see it visually and you will be able to physically move the propshaft back and forth with your hand. (more than a few thousands of an inch). I hope this is not the problem.

Good Luck