old johnson yr

[popsmazz1]

can someone tell me what yr a 7.5 model# ad-10 serial 1374625 is?

 

[tashasdaddy]

Re: old johnson yr

1956 manuals here: "http://www.outboardbooks.com/index.cfm?fuseaction=models.main&year=1956&ID=55223"
oil mix is either 16:1 or 24:1 not sure which.

 

[popsmazz1]

Re: old johnson yr

thanks for the info, I picked up this motor for free, but its been sitting for 25 yrs. its froze up, is there some way to break free?

 

[tashasdaddy]

Re: old johnson yr

not to optimistic, on it. the parts to repair that motor would be more than it is worth. you can drop the lower unit and see if the power head or the lower is froze up.

 

[Scaaty]

Re: old johnson yr

Pull it fer the parts..TRY and ebay..7.5 are few and far between..most bought the 5hp, or 10hp. Have a AD11 here with a tossed rod ...darn near wet broke with ebay fees listing parts..zero buyers...
Think yer dealing with junk on a 7.5 AD10.
Lower unit works with a bunch of years though..

 

[popsmazz1]

Re: old johnson yr

well I took the head off and layed the motor down put some 2 cyle oil in the cylinders and turned the flywheel with a rachett and it broke free, still a little tight but its getting better, the cylinders are smooth no scratches. do you think theres any hope for it?

 

[tabbott]

Re: old johnson yr

Who knows it may actually work. I wonder what froze it in the first place. Alot can go wrong and be damaged beyond the pistons, cylinders, and rings. What the heck at this point. See what happens.

 

[Scaaty]

Re: old johnson yr

Well, long at its free, yank the carb, clean it out, and go for fire at the plugs. BUT, I'd pop the point plate on the flywheel, and look at the coils (new are $20 each)..99% are cracked with age..but ya might get lucky. I've got a good recoil here if ya need one, plus some other stuff (not much)...and also most parts available anyway ..and..(can't remember, but pretty sure)..but the impeller is probably toast, and ya need to pop the powerhead to get at it to remove the top shift linkage..then drop the leg..
Mess with it, maybe we can get'er running again..

 

[wbeaton]

Re: old johnson yr

If its spinning there is hope. I'd want to know why it froze before I started it up. Maybe just lack of lube made it tight to turn or perhaps it was something worse. If its still tight to turn I'd say you still have some cause for concern.

The good thing is that you can tear that powerhead down and reassemble without much trouble or expense. Those motors are great, but they are also known for connecting rod problems. I had one that acted exactly like yours. It turned out that the con rod shifted slightly and was contacting the crank. I dismantled the motor, honed the cylinders and reseated everything. Now it runs great.

Change the coils (if they need it), install a new impeller and clean the carb. You have the makings of a great motor there. Most 5.5 hp parts will fit your motor. Only the powerhead is different. Also, there is a seal that sits on top of the driveshaft that you'l see when you go to change the impeller. Replace the o-ring and cork washer when you have it apart. Parts are still available.

Shoot me a PM with your email address and I'll send you the parts manual for your motor in pdf format.

 

[popsmazz1]

Re: old johnson yr

yes the coils and wires are cracked, gets spark to top cly. not much on btm. I am not going to spend any money on unless I can free it all the way, I am going to keep at it, I dont have a manual on it so I am not quite sure how to get it apart, my email is popsmazz@comcast.net thanks

 

[Scaaty]

Re: old johnson yr

yes the coils and wires are cracked, gets spark to top cly. not much on btm.

Ha, seems the last 4-5 old small Johnnys that made it my way did the same thing...no bottom spark! Also what parked a lot of them.

A little story on the AD 11 I picked up some other stuff.

Had the broken connecting rod tied to the handle. Got home, was looking it over...(it was froze too). Pulled the hat, looking it over, and it hit me. THE WHOLE THING WAS TOGETHER!. I figure they said the "heck with it, lets try it on just one piston!"..so would that be a AD 5.5?, ...3 3/4 hp?...(not a good idea it seemed!!)

 

[wbeaton]

Re: old johnson yr

I figure they said the "heck with it, lets try it on just one piston!"..so would that be a AD 5.5?, ...3 3/4 hp?...(not a good idea it seemed!!)

LOL - don't you wish you could have been a fly on the wall for that one! What a shame.

You can completely dismantle that motor and reassemble it without any additional costs. Only the price of any broken parts and head gasket in most cases. Its a very simple motor and worth the time.

 

[popsmazz1]

Re: old johnson yr

what is an ad11, ? mine is an ad10 i have the whole winter to mess with it.

 

[samo_ott]

Re: old johnson yr

an ad11 is 1 year newer, a 1957. if you have the whole winter then tear it down... it's relatively quick and easy and you learn lots along the way As WBeaton said, all you'll need is a head gasket and some goop to seal the 2 halfs of the crankcase together.

 

[Scaaty]

Re: old johnson yr

Yep, yank the head..(maybe on this.. HOPE no bolts twist off..one breaks ..stop!!!!!!..if its a salt water motor..don't even attempt it..and don't force it to begin with, and post it)
It has potential, but do it slowly, and let us know..simple motors...

 

[F_R]

Re: old johnson yr

A broken shock absorber in the lower unit will also make it stiff, even if you have the powerhead freed up.

 

[Scaaty]

Re: old johnson yr

A broken shock absorber in the lower unit will also make it stiff, even if you have the powerhead freed up.

Not to question, as ya know yer stuff, but my AD11 was F/N/R..nothing else in the DS system..? Correct me if my brain aint working again (aint the first time)

 

[popsmazz1]

Re: old johnson yr

head came off easy, still a little tight, may be able to save, whats the best way to clean ouy gas tank? has alot of crud in it.

 

[wildmaninal]

Re: old johnson yr

I personally have used pebbles or stones along with some gas to clean gas tanks of many types. Take a good bit of stones/rocks and load it into the gas tank along with some gas then slosh it around every which way you can. The rocks will help break loose any grime and dirt. Now keep in mind that the stones can be hard to get out of the tank. I also have used a pressure washer, but you must let it dry out before you use it again, don't want to get the water and gas mixed together. What size tank is it?

P.S.

If you have a plastic tank and you decide to use the pressure, use the pressure washer on low you don't want to blow it apart.

 

[wbeaton]

Re: old johnson yr

The 5.5 - 7.5 hp (both FNR) had a shock absorber in the lower unit to lessen the impact from hitting objects with the hubless the prop. If that shock absorber breaks it will make turning the driveshaft next to impossible.

You should separate the head from the lower unit to be sure the problem is in the powerhead as TD and FR have mentioned.

PS. Parts manual should be in your inbox.