Lower Unit Trouble

FasterDaddy

Seaman Apprentice
Joined
Oct 12, 2005
Messages
33
It's a '71 Chrysler shortshaft 8 HP Model: 82hb Serial 11034 .<br /><br />I went and got Clymer's service manual and started to winterize it last weekend. All was going well until I found only water, about two cups worth, draining out of the lower unit.<br /> :( <br />I've read and re-read the lower unit section of the the Clymer book and have concluded that I am probably not mechanically inclined enough to diagnose and repair this. And I don't want to make it worse.<br /><br />So what now? Is there amyone willing to work on it out there? I live outside Washington DC. I often go to upstate NY and could drop it off<br />between here and Syracuse. I suppose I could also ship it, since it weighs less than 50lbs -- which is one of the reasons I want to get it fixed!<br /><br />Backgound on this thing:<br />This spring a local O/B mechanic brought the little motor I bought as a teenager back to life, after long term storage. He had to do a complete tune up and he rebuilt the recoil starter. I dropped +$400.00 in getting this "Little Guy" (as my daughters now call it) running again. The mechanic says he pressure tested the lower unit and changed the lube oil. He said it didn't leak, and also said that it was a good thing b/c he would not be able to fix a lower unit leak on this motor. After all this was done, my daughters and I repaired the cracked cover and repainted it.<br /><br />My daughters have learned how to navigate around the lake on their own with this motor on our little aluminum boat. And it's running great. <br /><br />But, as far as I know the lower unit on the Little Guy has never been touched. What should I expect to pay to tear down and rebuild a lower unit on a 35 year old 8 hp?<br /><br />It may sound silly to spend more $ on a 35 year old motor, but WE really like the fact that it weighs less than 50lbs! New motors of this power seem to weight between 75 and 100 lbs, and I just can't see us putting that kind of weight on the back of this boat. <br /><br />Finally, Why have small outboards gotten to be WEIGHTY pigs in the last 25 years???<br /> DHALLIS@HOTMAIL.COM
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: Lower Unit Trouble

Hello fasterdaddy and welcome to Iboats. The first thing I would do is get some lower unit oil and fill it up as soon as possible. You dont want rust forming in there and the oil will protect it from doing that. Parts and mechanics are going to be tough to find. It is a lot easier to find parts for a bigger motor say from 20 HP and bigger then the one you have. Keep an eye on ebay. You might find a motor that has a trashed powerhead and get the lower unit for cheap. I would fill the unit and watch it for a couple of days and see if you can see it leaking. After each couple of times out re drain and refill the unit. Most chryslers lower units leak. Because of extensive wear on the prop and drive shafts they become pitted or grooved and dont hold a seal very well. My 1967 needs to be re filled every couple of months because water gets in there and I have gotten to the point where I dont worry about it any more. A note on pressure testing. A pressure test is usually non revealing on a drive or prop shaft leak. When motor is not running the seal is usually pretty good. When the motor is running any imperfection in the areas where the seal comes in contact with moving parts can create a leak even after it has been pressure tested.<br /><br />Good luck
 

FasterDaddy

Seaman Apprentice
Joined
Oct 12, 2005
Messages
33
Re: Lower Unit Trouble

Thanks Eurolarva... <br /><br />I wish I knew that the little bugger had a tendency to leak last spring. We probably put between 30 and 50 hours on it this year and I never checked it. Is it likely to be trashed? Does it matter that I looked for and found NO metal in the water that drained out?<br /><br />So if I can't get it fixed, then I keep putting lower unit oil in and watch it. Sounds like the rear differential of my 1994 Jeep. This I can do. <br /><br />One last thing... why are new motors so much heavier... even the two cycles!
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: Lower Unit Trouble

My 45 HP chrysler leaked real bad around the prop shaft for 3 years. I repleced the oil almost every trip. When the last of the water came out was there any rust? I cant remember if those gears are iron or aluminum. After each trip let motor sit for about a day and remove the drain plug and see if water comes out or the oil comes out. After awhile the water will settle to the bottom and it will come out first. If after being on the lake for an hour only water comes out then you have problems. If only a couple drops of water comes out dont worry about it. Try and find another lower unit on ebay. A seal kit costs about 30 bucks if they are still availible for your motor. It is not a real complicated procedure however kind of scary doing it the first time. I would get another lower unit if you can find one then take the old one apart using your manual. You have nothing to loose cause you have a different one If you get it apart and have problems post here and someone will help you.
 

FasterDaddy

Seaman Apprentice
Joined
Oct 12, 2005
Messages
33
Re: Lower Unit Trouble

There is a cheap 6 HP Chrysler of the same vintage on e-bay. Would it fit my 8 hp?
 

eurolarva

Rear Admiral
Joined
Jun 24, 2003
Messages
4,182
Re: Lower Unit Trouble

You will need to measure things like the mounting holes, how many splines the drive shaft has, and ask the seller to measure these things for you. Some lower units are one piece and some are two piece. If yours is one piece you will want to buy a one piece. Because of the age of your motor it is hard to cross reference part numbers to verify if it is interchangable or not. Also look at the water tube. Some are straight and some are bent. These things will determine if the other unit will work on your motor.
 
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