1988 Force 85hp lower unit assembly????

AWSHUX

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Hello, I am fairly new to working on boats but been working on cars and trucks my whole life. I just recently acquired a 1988 bass boat with the original 85hp Force outboard motor on it. The issue I'm having is that I'm putting the lower unit on it because it was off when I got it due to impeller needing replaced. The guy I got it from took the lower unit off and never put it back on. So I put a new impeller on and bolted on the lower unit but now the gear shifter rod seems to be too long. It won't go into reverse because it's hitting the bottom of the upper unit,,if that makes sense. I discovered that the rod is threaded and I screwed it down as far as it will go but it's still too long. Is there anything that is supposed to go in between the upper and lower units, like a seal, gasket, or something to take up some space? It's only about a 1/4inch off. The model is 856X8B and serial 4550. Thanks in advance.
 

SkiDad

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You might have to adjust the two nuts just under the carbs. If you manualy shift the linkage you will see which ones I mean. They go up and down. If you loosen the top one a turn and then tighten the bottom one it will push the shifter rod down more. Not sure why you would need to do that unless it's not the original lower unit. Sorry it's late. But a picture could help us.

Ps. There are no gaskets.
 
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Frank Acampora

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Like jerry said, A couple of photos would do wonders. You have me a bit confused because down on the shift rod is Forward gear. So unless you are talking about the shift rod hitting the kingpin when moved up, it doesn't compute.
 

pnwboat

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I wonder if the shift linkage pin was accidentally removed and then re-inserted incorrectly so that the shifting paw inside the lower unit is out of whack causing the symptoms that your experiencing?
 

AWSHUX

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Sorry guys, I've been trying to upload a picture for two days with no luck. The rod I'm talking about is the one that sticks up out of the lower unit. It connects to a backward "L" shaped rod sticking out of the bottom of the upper unit. The rod moves up and down as you put it in forward and reverse. It pushes down for forward and pulls up for reverse. The problem is, the rod seems to be too long as it hits the bottom of the upper unit before it can engage reverse.
 

AWSHUX

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Like jerry said, A couple of photos would do wonders. You have me a bit confused because down on the shift rod is Forward gear. So unless you are talking about the shift rod hitting the kingpin when moved up, it doesn't compute.
Yes.....it is hitting the kingpin before it can engage reverse.
 

Frank Acampora

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OH! Then you need to adjust the two lock nuts under the bottom carb to lower the rod a bit. These nuts are difficult to access on the three cylinder engines and you will need a LOT of patience. you need to loosen the top nut and tighten up the bottom nut the same amount. Do it in small increments so that you don't lose forward gear.

Typically, I screw in the lower shift rod all the way then back it out only enough to engage the hole for the cotter pin. Final adjustment for gear engagement is made at the upper rod adjusting nuts.
 
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AWSHUX

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Ok thanks,,, I'll give that a shot. But I even dissconnected the two rods and tried shifting the lower rod with a pair of pliers and it still hits the kingpin. If I hold the lower rod all the way up against the kingpin, I can barely feel the gears trying to touch if I turn the prop but never fully engages. Could it be a different lower unit than what was on it or a sign of being worn out? I know it seems to be a lot of slack in the gears but me being new to the boating world, I didn't know if that was common or not. With the gears fully engaged in forward, I can turn the prop about a 1/4 of a turn before it tries to turn the motor. Does that sound about right?
 

jerryjerry05

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If the PO just changed the imp there should be NO reason to adjust anything.
Those nuts under the carb is one of the last things to be adjusted.
Send me a pm with your e-mail and I'll get your pics and post them.
 

AWSHUX

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Yeah that's what I was thinking. The PO said that it needed an impeller and after taking the lower unit off he discovered that he had ordered the wrong impeller. So he just said forget it and didn't mess with it anymore. So I'm just wondering if that'sa different lower unit than what came on it. I just thought everything would line right back up if it's the one that came off of it.

I'll PM you my email.
 

Frank Acampora

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ALL three and four cylinder lower units on Chrysler and Force engines before the Mercury lower unit have the same length lower shift rod. That INCLUDES the 25 inch extra long engines. Now, if the joker somehow swapped a different shift rod-- that's a different story. It also occurs to me that you are saying the adapter hits the kingpin, not the kingpin mount. If you can see the kingpin sticking down below the mount/clamp then it is either too long or has shifted down.
 

jerryjerry05

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Gonna try to load his pics???
Not gonna load.
Something about Android.I can see them but they won't download or upload.

I see the pics. The problem is in the lower.
Your gonna need to take it apart and fit the shift yoke in right.
 

AWSHUX

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Hey guys, sorry for the long delay. I just went ahead and bought a whole lower unit. It fits perfectly! I have no idea what the lower unit I took off goes to but it definitely doesn't belong on this motor. Now my question is,, what size is the nut that holds the propeller on? The one I bought didn't come with one on it and the one off the old one is too big. From what I can tell by using a tape measure is that it's about a 5/8" fine thread. That sound about right?
 

SkiDad

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I believe you are right on 5/8 but it has to be a special nylon lock nut. There is a thread about this within the last month.
 
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