1989 johnson 70 hp

I was hoping I could get some opinions from everyone here on a possible rebuild. The motor is a 89 70 hp vro. I have an opportunity to buy a boat from a friend for a 1000 dollars, but the motor needs to be rebuilt. The boat itself is a 1650 wahoo center console in ok condition, I really like the style of it, but it does need some work and has been neglected. The major problem is that the engine only has 60lbs on compression on the middle cylinder and approximately 110 on the other two. The motor runs but won't idle. I pulled the head and there is scoring on the cylinder walls and some piston damage. I think they will need to be bored. Do you think it would be cost effective to buy and rebuild or let it go on down the road and find something that is in running condition? Any input would be appreciated.

Re: 1989 johnson 70 hp

mcgyver6857 said:

I was hoping I could get some opinions from everyone here on a possible rebuild. The motor is a 89 70 hp vro. I have an opportunity to buy a boat from a friend for a 1000 dollars, but the motor needs to be rebuilt. The boat itself is a 1650 wahoo center console in ok condition, I really like the style of it, but it does need some work and has been neglected. The major problem is that the engine only has 60lbs on compression on the middle cylinder and approximately 110 on the other two. The motor runs but won't idle. I pulled the head and there is scoring on the cylinder walls and some piston damage. I think they will need to be bored. Do you think it would be cost effective to buy and rebuild or let it go on down the road and find something that is in running condition? Any input would be appreciated.

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This totally depends on what parts need replacing and who will be doing the work. If you are going to pay a mechanic to rebuild the no. Not a chance it will be worth it. If you are going to do the work and buy the parts..maybe.

Any scoring on the cylinder and it will need to be rebored. Factor in the cost of reboring all 3 cylinders, or at least honing the other 2. The killer will be the crankshaft condition. If it's reusable then that will save you a lot of bucks on parts. Plan on 3 sets of rings, at least one new piston for the overbored cyl, new lower crank bearing, new connecting rod bearings, possibly new center main bearings on the crank, and possibly new upper main bearing. Also needle bearings on wrist pin may need replacing.

As usual powerhead gasket set, gel seal and gasket sealing compound will be needed.


Then you have to look at the condition of the boat...does it have rot in the floors or transom? Boat restoration is a whole new ball game.


Cheers and good luck~!

Re: 1989 johnson 70 hp

Thanks for the quick reply the boat itself seems ok, no soft floors, I haven't taken the transducer off yet to see if there is water in the transom. I will be doing the work myself as the local marina's want upwards of 2800 for a rebuild on this motor . I have never rebuilt an outboard before but plenty of dirt scratchers. I see they have kits online that come with everything including bearings for around 450, seems reasonable. Or complete reman powerheads for around 1500. Wondering if that is too much to spend on a boat like this. I will take some pictures of the package tomorrow if you think that will help determine if it is worth the money to fix it up. Thanks again.

Re: 1989 johnson 70 hp

mcgyver6857 said:

Thanks for the quick reply the boat itself seems ok, no soft floors, I haven't taken the transducer off yet to see if there is water in the transom. I will be doing the work myself as the local marina's want upwards of 2800 for a rebuild on this motor . I have never rebuilt an outboard before but plenty of dirt scratchers. I see they have kits online that come with everything including bearing for around 450, seems reasonable. Or complete reman powerheads for around 1500.

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Yeah there are some good kits available if you live in the states. My advice is if you buy the boat, tear the motor down before buying any parts to see if it is worth rebuilding. You may find that it's not worth it in which case you can part out the old motor and shop around for another project motor.

#1 thing to do..get a factory service manual for the motor. Not seloc or clymer but factory OMC.

I recently rebuilt at 1995 70hp evinrude. Might find some useful info on this post http://forums.iboats.com/showthread.php?t=361179.

Re: 1989 johnson 70 hp

sorry edited my last post before reading yours. I did look at your thread before posting some good info there. I do live in the states so it looks like parts won't be much of an issue as long as the crank in the thing doesn't look like yours did. Do you think any pictures of the package would help determining fix or pass?

Re: 1989 johnson 70 hp

mcgyver6857 said:

sorry edited my last post before reading yours. I did look at your thread before posting some good info there. I do live in the states so it looks like parts won't be much of an issue as long as the crank in the thing doesn't look like yours did. Do you think any pictures of the package would help determining fix or pass?

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Sure pics can only help. The reason I decided to rebuild mine was that the electrical and carbs were in excellent shape, also the motor itself had no rust or corrosion. I was out driving that motor today, runs like it's brand new for less than 1/4 the cost

Still a 1000 bucks for that boat, trailer and motor is cheap. Cheap if the boat isn't rotten, the motor is fixable and the trailer isn't rusted out.

Re: 1989 johnson 70 hp

Depends on how much you are prepared to do and how long you want to spend before you take it out and have some fun. A little more investment could well get you something that you can tow straight to the ramp. I also do not like purchasing from "friends" as it can cause bad blood down the road.
Just my 2 cents though.

Re: 1989 johnson 70 hp

Well after pricing everything today I am almost ready to go ahead with this. It will be a good learning experience. Is this a project you would all like to see documented here and provide help as needed? Also does anyone have experience with the rebuild kits that are available, which have been used? Seems they are a good value, but are they quality parts or bottom of the barrel to match their prices?

Re: 1989 johnson 70 hp

your crank is probably fine as long as the motor wasnt blown up,sunk and forgotten about,.Do the work yourself,the hardest part will be removing the powerhead mounting bolts .If the boat was used in saltwater alot,they may be a bit stuck.I go a few tricks ,so if they are stuck,let me know by private message BEFORE you snap off the heads.As for the rebuild,you need a good machine shop that does outboards.After the machine work ,you should have it back together in a few hrs.Your a mechanic on bikes,this will be easier.Im pretty sure those wahoo boats are foam core ,correct?Like a boston Wahler .I dont think they have wood in the transome,or at least not the one Im thinking of.For $1000 ,its worth the gamble ,especially if you like the boat.So for about $2000 or less ,you have a rebuilt outboard and a decent boat.I will say this though.I live in the Fl.Keys .Down here and the whole state for that matter ,there are deals all over.But you got to be there.Be sure to rebuild the carbs,good chance that was the problem,fuel starve one cylinder ,and you got not lube and a lean out problem.

Re: 1989 johnson 70 hp

That 70 is known as one of the motors that are worth rebuilding. Also, being a popular engine, you might find a parts motor and swap out the block, etc.

Take a good look at the power trim tilt assembly; the motor will swell and rust and you have to take the motor off to get to one screw. So if yours is funky, think about upgrading while you have it in pieces. also the little tube at the bottom went out on mine and it's an expensive part for what it is.

After my 1988 70 got salt water in it, I got an 86!

The wahoo is a whaler clone, so unless the transom gives when you pull on the motor, it will be fine. Some get waterlogged if there is a leak between the hulls, but some whaler guys maintain that the extra weight won't matter that much.

$1000 seems a little high for a neglected mid-tier brand boat with a bad motor. But it's a popular hull and a popular motor. And you didn't say if it's a salt water boat.

Be sure to replace the water pump while you're at it.

There's a lot of debate about disconnecting the VRO but the part you need if you do is pricey. Keep an eye on the oil and its line and be sure your alarms work. It doesn't have that gravity tank back-up that new motors have.