Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

[Pmccraney]

I have a question for the knowledgeable folks on this form.

I am looking to purchase a boat this weekend, which is going to be a winter project.

It's got an 85 hp Johnson with model No. 85ESL74B. In doing some research on the internet, it appears that this is a 1974 model. Is that right? See picture below.

I've got a decent deal on it, and I am primarily interested in the hull and trailer as I will probably re-power the boat one day with a more modern set-up. Nonetheless, I am told the motor is a reliable runner (to be confirmed on lake test), and I would like to get a reasonable amount of use out of it until it craps out or starts requiring expensive maintenance or having to deal with NLA parts, etc...

In doing some further research on this model year, I came across some info that has led to some questions.

1. It appears that Johnson o/b s had the dreaded "electric shift" (or hydro-electric shift) from the mid 60s to 72. It appears that this set-up was widely hated and so they phased it out in 1972. Is this correct?

2. It appears that from approximately 73-77, Johnson switched over to a mechanical/hydraulic shift, and then in 78 went to a full mechanical shift. Again, is this correct?

If so, it appears that my motor falls in this "tweener" stage between electric shift and full mechanical shift. I have read that the lower unit gear assembly is "reversed" for motors with this set-up and thus makes simply switching out a lower unit problematic.

My primary question: Other than the above (the reverse gear box) what is the primary difference in terms of function, use, maintenance, etc... between a "mechanical/hydraulic" shift and full mechanical shift? This may be a dumb question, but do you have to use special hydraulic fluid for the shift mechanism?

Any other particulars or nuances that I should be aware of if I want to use this motor for a couple of seasons before I repower?

Thanks very much,
Patrick

 

[crb478]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

If it is a 74 115 then it is not an electric shift, but
The hydro mechanical which is fairly trouble free. That motor is easy to work on and the lower unit drops simularly to later models. It is a basic crossflow design and you may not wear it out for years to come if at all. Parts are readily available and exchangable between the 73-77 models. Check the compression and see how it runs you might not need to repower.

 

[TrueNorthist]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

What crb said... But for what its worth I know a fella up the coast that has run one of those motors from new and it still scoots around nicely. And he runs the snot out of it yearly. Simple design and relatively bullet proof. Depending on how well it has been cared for, I can see you running it for quite a while before it packs it in. No worries on the gear-case front if it shifts smoothly and you continue to maintain it well. Hint: Use nothing but the recommended OMC Gear oil and replace the water pump, just for peace of mind.

 

[Pmccraney]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Thanks guys, I really appreciate the feedback.

Couple of quick follow-up questions:
1. What is a typical/acceptable compression level/range on these?

2. What should I be looking for in terms of rpms and temp assuming the tach and temp gauges work?

3. On the gear oil, i read that the electric shifts require what I believe is a 90 weight? Is the OMC recommended oil the same for these?

Thanks a bunch; the info you gave above has already been very very helpful!

 

[TrueNorthist]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

You should not use anything but the recommended Evenrude gear oil in that gearcase as regular 90 is too heavy. I believe the OMC stuff is about a 75(?) and also has additives to keep foaming down etc. It is such a small added cost that it just makes sense to follow OEM specs with those gear-cases.

Edit. Sorry... Johnson.

 

[Daviet]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

1. They do not list compression ratios, but if you have anywhere from 100-125, and within 10% of each other, you are good. If the engine has been sitting for awhile it might be on the low side.
2. Without looking for a manual, the RPM at WOT should be somewhere around 5500-5700. Temp should be around 125-130, Could be a little of on specs, don't have a manual in front of me.
3. You do not have an electric shift, they use type "C" oil, yours is hydro-mechanical and use premium lower unit oil, available at your dealer or from sierra.

 

[Pmccraney]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Great info, thanks guys!

I've got the manual on order, but this helped me get some quick answers. Appreciate the guidance.

 

[Daviet]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Wise man, hope you ordered a factory manual.

 

[Pmccraney]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Yes, factory manual... Just wanted to follow up and say thanks again, and show you a few pictures.

Compression was an even 120 on all 4 cylinders: Actually, 1 cylinder was a about 10 psi lower, but I sprayed some fogging oil in the cylinder and it jumped right up to 120 on the next test:

Here is me checking the gear oil... No metal shavings and no foul odor... Nothing looked or smelled burnt. However, it did look a little milky/watery - the P.O. said he had not changed the gear oil in the 5 years that he had owned the boat... Luckily, he only ran it about 4 times during his ownership...

I changed out the gear oil with the Manufacturer recommended gear oil that I bought from my local dealer; She ran like a top on the lake test (this is a video - you can click on the picture to view it):



I did go ahead with the purchase, because the hull and trailer were in pretty good shape, and the motor ran like a top - cranked right up, idled well, never died at idle, etc...

However, I have a couple of questions for you guys:

1. Absence of Tilt and Trim assembly is bugging me... I know I am going to want it. This may need to be posted on the electrical forum, but how big of a pain is to hook up one of these, in terms of bolting it up, hooking up the relay and necessary controls (or do you have to upgrade change your existing controls?).

2. There are no gauges in this boat -- weird. How difficult is to hook up the necessary sending units and wires for temp, tach, etc... Are there any good threads on this board or stickies up top that show this?

3. The starter works/fires great, but the key hole for the starter is a little worn/loose... The key wants to start backing out of the key-hole once you get underway... It will literally fall out if you don't keep an eye on it... Is it possible to fix this, or should I just ditch the whole control unit anyway since I want t & t set-up?

Thanks again!!!

Patrick

 

[glnbnz]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Hi Patrick,

I am signing on to your Motor thread also as I have a 1975 85HP Johnson strapped on the back of my boat.

I am a little worried about the milky color of your gear oil. I changed mine once when I bought the boat...then I took it out once and then I changed it again. It didn't look like that so I am curious to what the experts have to say.

Also check out the sticky thread called Top Secret File UPDATED 8/1/2012 there is a lot of great information there

 

[royal0014]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Sounds like you got a great 'ol engine! Now to take care of it......

The milky oil is from water intrusion. Time to drop the lower unit and replace the seals. As long as you're there, replace the impeller, it is way past due.......The manual is a good start, anything else is right here on iboats.......

Good Luck!

<<)))(((>>

 

[Pmccraney]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Thanks royal... I've already purchased the new impeller from local dealer... They did not have the water pump kit in stock, but I have one on order.

I will order replace the seals while I am in there... Building an ouboard stand this evening to house the motor while I do some work on it and the boat.

Thanks!

 

[crb478]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

The origional tilt n trims are hard to find and pricey. You can buy a new cmc tilt and trim for a little more. Neither are hard to hook up nor are any gauges. As said before milky means there was some water intrusion.

 

[McGR]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

I used to run a '76 Johnson 85hp on my old rig. It was a real solid motor that always impressed me with its performance and reliability.

If I were you, I think I would put a few $ into the 85hp and plan on running it. As others have mentioned, you could do a lot worse with a newer "better" motor. These V4 OMCs are really good motors that are relatively easy to work on. If you give that one some TLC, it might give you better service than one of the "new and improved" models.

I'd also recommend the addition a CMC aftermarket power trim unit, I had one on my 85hp and it worked great.

Anyway... regarding the lower unit lube. The original factory recommendation was to use the lower viscosity "OMC Premium Blend/Type C" lube. However, OMC later changed their recommendation to use Premium Blend only for electric shift models and all other motors to use "Hi-Vis" lube. Basically, OMC Hi-Vis is your typical 90W or 80W-90 lube. In short, you don't need exotic lube for this motor most of the l/u lubes you'd find in your local auto parts, marine or department stores will probably work fine in your lower unit. See attachment:

http://forums.iboats.com/attachment.php?attachmentid=64146&d=1281901066

 

[TrueNorthist]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Great to see ya havin some fun out there in yer new boat! I can see you running that motor for a long time judging by your dedication to detail. I just wish I could hear the motor better. (Mechanic pron ) As far as the milky gear-oil goes... I have a leaky seal on both of my motors, and as I am incredibly lazy with my own stuff I just change the oil every couple of trips. But I would definitely heed the advice of the other more clever fellows above and find the source of the water intrusion and fix it asap.

I will also second (third or fourth) the CMC power trim kit. Really easy to install, and like your "new" motor, also very stout. Gauges etc are fairly simple to install so go nuts and make a whole panel! I made a teak panel myself and installed a whole whack of idiot lights and stuff to draw attention away from any driftwood or other such annoying hazards. Loads of fun.

Good to see you are getting a new water pump kit. I usually do the whole works on something that has been in there for more than 5 years, rather than just the impeller. The water pump is all that lays between a good, running motor and an anchor. On the key front, I would replace just the key switch assy. That too will be easy. No need to replace the whole remote.

 

[jbcurt00]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

As it may come up again, I'll post this here too:

Dood, check under that cowel, have ya got a lifting ring mounted on block there? That might have made your life easier. Some have em some don't.

Seems like part # 69 is a lift ring:

#69 — 318485 — 318485 — LIFT BRKT., CYLINDER (1 required per assembly)
	0318485	0318485 - Vintage, BRACKET Replaces OEM # 0318485			$6.00	$6.00	4 in stock.

From here

 

[mark1961]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Also visible in the top left corner of this pic.....

 

[rrumba]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

nice catch there mark. Looks like you are all set there PM

 

[Pmccraney]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Thanks everyone.. Glad the forums are back online... The UPS guy brought me a little happy yesterday....

Already a good learning tool!

 

[jbcurt00]

Re: Questions about 1974 Johnson 85 hp (outboard newbie - please help!)

Looks like your service manual is a water survivor too

That manual & the parts diagrams w/ part#'s are great!

Welcome back :facepalm: glad you & your's are high & dry