'83 70hp johnson gear case leak

[xxlostinthoughtxx]

I just purchased a boat with the 70 johnson and i hooked it up to the flush muffs and after running it found that the engine raced as soon as starting. I found that the linkage and adjustments were all out of wack. So I was starting and stopping the moter trying to figure out the problem but i left the hose on. it was only a few minutes each time. While i was running the motor i noticed a pile of gear oil under the motor. It is coming out where the prop is. maybe only about 200ml or so was on the ground. but after turning off the motor and water, a little more slowly leaked out as the water exited the motor. I see its pretty clear that i have seal issues. I am going to do a whole seal kit on it. My question is how much oil does it hold and what if any special tools will i need. also if theres anything else i should look out for while im at it

 

[SigSaurP229]

Re: '83 70hp johnson gear case leak

It may not be a gear case leak it may be unburned two stroke oil. Check the gear oil first if it is white or creamy/milky then you have a gear case leak.

 

[edfishing2]

Re: '83 70hp johnson gear case leak

It is around 32 oz of gear case oil. And yes to rebuild or reseal the gearcase you do need some special tools. The main non-standard workshop tool is a huge pair of snap ring pliers. Like for 3in snap rings. I think the over all length on the snap ring pliers is like 15 or 16 inches. While you are there look at the shift dog (splined id that rides between the forward gear and reverse gear. The tips of the front and/or rear of the shift dog engage in grooves milled in the face of both the forward and reverse gear. These TEETH are worth looking at if you dig that far. They get kinda rounded over sometimes and can be resurfaced at a good machine shop but they are hardened steel.

 

[xxlostinthoughtxx]

Re: '83 70hp johnson gear case leak

thanks for the info. I guess im going to invest in those snap ring pliers. i have plenty of time to get them while i wait for the kit to come in. Would you know where abouts i might look for the pliers? Auto store maybe?

 

[AlTn]

Re: '83 70hp johnson gear case leak

use the search box <upper right>..type in "snap ring pliers"....

 

[SigSaurP229]

Re: '83 70hp johnson gear case leak

thanks for the info. I guess im going to invest in those snap ring pliers. i have plenty of time to get them while i wait for the kit to come in. Would you know where abouts i might look for the pliers? Auto store maybe?

To just reseal you don't need the snap ring pliers. All you need is a way to pull the Bearing carrier, go to autozone and rent a harmonic balancer get some threaded rod to feed into the bearing carrier. Then you use a puller to pull the bearing carrier the rest is easy going.

 

[xxlostinthoughtxx]

Re: '83 70hp johnson gear case leak

awesome. the simpler the better. unfortunately i have discovered that im only firering on 2 cylinders. i pulled the heads to take a look at the pistons and walls and i found that the top and middle cylinder were wet with gas/oil mixture (i was checking compression just prior). the bottom cylinder was near bone dry. i have compression across all cylinders and spark. is it safe to assume my problem lies in the carb? i can actually get the third cylinder to fire by finagaling the choke once its running on the 2..