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b99 Johnson 70hp lower unit

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ptownbubba

Contributing Member
"Well it happened, my '96

"Well it happened, my '96 70 hp Johnson made a rattle noise, and then just quit spinning the prop. The motor runs, no prop spin. Instead of hauling the whole pontoon boat to the boat-motor doctor, I was just going to pull lower unit and take it to him. Any secrets to doing that, or just put in neutral position, remove bolts and slip it off ?

I assume it is in the gearbox,,,, not much chance the downshaft spline in motor would fail is there ????? I will check lower unit oil for debris,, or other signs."
 
"I removed the lower unit bolt

"I removed the lower unit bolts [ 6 ] it will slide out about 1/2", then stop,, is there a shift rod disconnect, or does the lower unit just "pop" off shift rod ?"
 
On my motor the bolt that hold

On my motor the bolt that holds the shift rod is up under the carbs. It doesn't "pop" off.
 
"Thanks Ned,,,, do you have a

"Thanks Ned,,,, do you have a 70HP 3 cyl Johnson ?

I can see the shift rod, but can't see any bolt,,, do you need to remove carb to get to it ??? Also,, the rod up there has a "z" shape to it,,, doesn't look like it would go through the grommets on the way out ?????

I did screw up,, the motor is a 96 not 99"
 
i do and yes there is a screw

i do and yes there is a screw under the carbs you have to unscrew to disconect the shift rod.
i have quite a bit of experience with them considering i rebuilt my own.
any other questions about it feel free to ask.
 
"Thanks for the quick response

"Thanks for the quick response,,,, I think my lower unit died yesterday on the river,, rats,,,,,,,,,, rattled then nothin' spun. The motor was fine but no prop spin,,,, Not sure why, did not hit anything.

So,,, somewhere under the carb there is a bolt I need to remove.... wow looked a bunch of times,,, can't get a good look up in there,, plus this is on a pontoon so it is tough to see up in front of motor. and the z shape in rod at top or motor end,,,,,,,,,,,, that will make through shift rod tube ???

1996 70 HP Johnson 3 cyl
J70TLEUM"
 
"ok,, now I am scared,,,, I un

"ok,, now I am scared,,,, I unhooked the linkage at the motor,,, that let lower unit drop out a little farther,,,, from the linkage side I can see where the rod hooks to the pivot,,,,,,,,,,, but,,,,,,,,,,,,, it is not a cap screw or a slotted screw head,, in fact no head,,, unless this is not a threaded pin, but like a push pin , but how does it stay in ??? ,,,,,,,,,,,,,,,,,,,, or,,,,,,,,,,,,,,,,,, oh my God,,, the last guy who did this,,,,,,,,, [ had lower unit worked on before a few years ago at a boat shop ] twisted the head off the cap screw when he tightened it,,,,,, how screwed am I now !!!!!!!!?????????????????


"IF" that bolt or pin is a cap screw, with the head twisted off, I may be able to drill a large access hole near the fuel line connector of motor housing, and with a long drill, drill out the cap screw and replace it when I re-assemble. Unless I am all wrong,,, is that a pin or a bolt that connects shift rod to the linkage pivot ????

----- Original Message -----"
 
"Greg,
the lower motor housin

"Greg,
the lower motor housing should come off as well. I think they are held together with a few bolts. Might be worth looking into.
Good Luck"
 
"Thanks,,,,,,,, I was lookin

"Thanks,,,,,,,, I was looking at that shrowd or housing,,,, was not sure it would come off with powerhead on,,,, what do you think about the shift rod connection to shift linkage at powerhead,,,,, is that a cap screw,, or does one side "flip" away to let rod unhook ?"
 
"Based on the model # you prov

"Based on the model # you provided your motor is a 97 not 96.

Here is a link to a diagram of the lower motor cover. if you study it you might be able to figure out how to get it apart.

you might find something on the shift rod there as well. You might want to get a manual it make this alot easier. Links are at the top of the page

http://ishopmarine.com/ishop/jsp/AsplIsmCcatViewBase.jsp?reqFor=29&req4Browse=1& lvlCode=5&pCode=C0257168&path=BMC~A0000022~M0013367~M0013692~M0013696~C0257168&d ocId=&docName=&isForSupStore=false&cCatFilter=&eCatSupFldr="
 
"Thank you very much,,,,,,,,,,

"Thank you very much,,,,,,,,,,,,on the motor it had those numbers, with 1996 as I assume the date mfg.,,

J70TLEUM
G04221341"
 
"I am really thinking the last

"I am really thinking the last guy who repaired the lower unit ,,, spun the head off the bolt, cap screw, or whatever off the the shift rod to remote control bracket,,,,,,,,,,,,,,,, that really puts me in a bind,,,,,,,,,,,ugh !"
 
"Have a look at the starb side

"Have a look at the starb side of under the carbs where the shift shaft comes from the linkage. If not mistaken it should be like a big paper clip going though the shaft. If so, pull out the clip, push the shaft to port and the pin gets released from the shift rod."
 
"Not really seeing a "pape

"Not really seeing a "paper-clip" looking thing,,,,,,, what a God awfull place to have a disconnect point,,, both ends of the so-called pin look smooth, so don't know if head is broken or sheared off, could be some sort of flip up holder or something,,,,,,,,,,,,, driving me nuts whatever it is. Looking from the shift linkage side [ right/starboard ] there is a black plastic part of the shift linkage that pin is in, maybe it pops over and off ????????? on the fuel filter side, it is metal, either way it is tucked under so far you can not really see what is going on from either side . ARGHHHHHH !!!!!"
 
"Greg,
I feel your pain! Are

"Greg,
I feel your pain! Are you sure your looking in the right area? On the front side of the motor the shift rod will come straight up throught the gromet and connect to a lever. That is the connection you want to disconnect."
 
"Got It !!!!!!!!!!!!!!!
The s

"Got It !!!!!!!!!!!!!!!
The shift linkage rod goes under the motor, on the end of that is where there is a "pin" connect or coupler that hooks to the shift rod. What you have to do, is take the hair pin out of the linkage rod, which is right out there in plain sight,,, then push the rod "in" all the way,,, that pushes connecting pin out of the connector and the shift rod end. Now that I got it off the instructions from here are right on,,,but I kept looking past the hair pin/paper clip,,,trying to somehow disconnect under the motor, maybe I am too stupid to work on motors,,,,,,,Now off to the Motor Doctor and big $$$$$$$$

Thank you so much for all the help,,,,,"
 
"Start at the shift cable atta

"Start at the shift cable attachment point (cable end stb side. Follow the linkage system forward.You will find a lever going 90 degr under the carbs through some bushings and end at where the shift rod comes up. On the stb side of the bushings a clip goes straight through the shift lever. Clip looks like a big 'R' Pull it out! To be able to push the shift lever far enough to port to get the pin free, You may have to remove the lower carb! You even better start with the gear housing tightened up (use 2 screws only)
The older version of the 3 cyl had a screw that went through the shift rod from the port side."
 
"yes that was what i was think

"yes that was what i was thinking of the older model, so it is a hair pin now well its pretty basic then. so i presum you have it off now.

good luck"
 
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