fix the Mercury or Johnson

[Kevin W]

I am also weighing my options.
basically i had a bad day Saturday and hit a rock with my lower unit and it is still in the pond.
Like i said bad day.
I have a 79 merc 70hp with good compression but the lower end is in the pond.(it broke above the lower unit )
I have a brother in-law that has a rot box boat with an 85 Johnson 70hp VRO engine that has been sitting for at least 5 years.
I belive the Johnson has low hours so it may just need carbs cleaned, water pump and tuning etc..
Would it be wiser to take the Johnson and run with it or fix the Merc?

 

[jtexas]

Re: fix the Mercury or Johnson

dang, sorry to hear about your troubles. the boat's still in the pond or you knocked the L/U clean off? sounds like quite a jolt. Wonder if it damaged any engine internals (drive shave, crank, ???).

With the johnson, it'd be pretty easy to check compression, maybe even pull the cyl head before committing any cash...I see it as a purely economic decision. Age difference wouldn't matter, 20 years old vs. 25. Hundred or so for carb kits, water pump kit, spark plugs, etc. plus whatever the BIL wants, vs. a rebuilt merc gearcase.

good luck.

 

[Kevin W]

Re: fix the Mercury or Johnson

dang, sorry to hear about your troubles. the boat's still in the pond or you knocked the L/U clean off? sounds like quite a jolt. Wonder if it damaged any engine internals (drive shave, crank, ???).

With the johnson, it'd be pretty easy to check compression, maybe even pull the cyl head before committing any cash...I see it as a purely economic decision. Age difference wouldn't matter, 20 years old vs. 25. Hundred or so for carb kits, water pump kit, spark plugs, etc. plus whatever the BIL wants, vs. a rebuilt merc gearcase.

good luck.

Basically it snaped the lower collum at the bolts and away went the lower unit, driveshaft,and everything attached.
The powerhead was still running after i hit it so i don't think it has any issues.
My trolling motor got us back. (thanks Minn-Kota)
If the water was clearer water i would go back and attempt to recover whats left but i think that lower unit is hopeless.

Currently i think the Johnson is my best bet.

 

[mkrupp]

Re: fix the Mercury or Johnson

i would agree i would go with the johnson, you know what youre getting, just some tuning up and you will be ready to go, unless your a die hard merc fan.

 

[Kevin W]

Re: fix the Mercury or Johnson

No, i am not commited to the Merc.
It was most definately a very good engine and i am pretty sure it is still a good powerhead but i am thinking it may be cheaper to fix the Johnson and either part out the merc or find parts for it.
Just in case i have another bad fishing day.

 

[cobra 3.0]

Re: fix the Mercury or Johnson

The Johnson has 5 years of sitting around? That's a long time for rust to settle into the cylinders, pistons and rings...You may be changing out for more troubles. Check it out real well before you decide.

 

[mkrupp]

Re: fix the Mercury or Johnson

well what did you decide upon?

 

[Kevin W]

Re: fix the Mercury or Johnson

I will have to fully inspect the jonny to make a full decision.
I am most definately leaning toward the johnson unless i suddently find good priced parts for the merc.

 

[Kevin W]

Re: fix the Mercury or Johnson

Well the Johnson is on the boat!
Its in even better shape than i imagined.
before storing the motor my brother inlaw fogged the engine, drained the carbs.
i bought carb kits and a water pump to get started with the restoration and the carbs where Very clean inside.
basically i only needed to clean the bowls out.
the rest was Dry.
I drained the lower end and the oil was still clean.
It appears like it has an updated VRO on it. maybe VRO2?
The only thing that i would say needs TLC is the shock absorber.
i have a feeling water has got into it because it creaks something wicked both up and down.
i tried penetrating oil around it with no luck.
Are they pressurize inside ? are the seviceable?

 

[SeaKaye12]

Re: fix the Mercury or Johnson

Hey Kevin,

I suppose that the BIL also had the controls for the Johnson and the cables were the right length and all that?? If so, you're lucky there too...

I bet you can get the Merc back in the running fairly easily too...I would imagine that there are a lot more older Mercs around with powerhead issues than lower unit issues. You can probably find a complete engine with a weak cylinder or two on the cheap and just switch over the bottom half and you'll have a strong back-up motor for yourself or you can put it up for sale...since you also have the controls for it.

No more bad days now....ok??

BTW...did you ever find out what it was that you hit?? Tie a bouy marker to that thing...whatever it is.

Chuck

 

[Kevin W]

Re: fix the Mercury or Johnson

Hey Kevin,

I suppose that the BIL also had the controls for the Johnson and the cables were the right length and all that?? If so, you're lucky there too...

I bet you can get the Merc back in the running fairly easily too...I would imagine that there are a lot more older Mercs around with powerhead issues than lower unit issues. You can probably find a complete engine with a weak cylinder or two on the cheap and just switch over the bottom half and you'll have a strong back-up motor for yourself or you can put it up for sale...since you also have the controls for it.

No more bad days now....ok??

BTW...did you ever find out what it was that you hit?? Tie a bouy marker to that thing...whatever it is.

Chuck

Yep the johnson has controls, and its about the same size boat too so the cables should fit easily.

I do plan on fixing the Merc.
It was a really good motor until the big bang.
i figure i can scrounge up parts over time or find an engine with a smoked powerhead.

I fould out after telling the story to several people that that area of the pond is loaded with rocks.
(alot of good that does me now)
I am pretty sure I hit either a big mutha rock or the last guy with bad luck's motor.

No more bad days planned anyway.

 

[jtexas]

Re: fix the Mercury or Johnson

you didn't mention in your original post that the BIL knew what he was doing...makes a difference, eh?

you can find the parts catalogue/schematics for your new motor including the TNT unit at
http://epc.brp.com/default.aspx?brands=ej&lang=E

Drill down to your year/model.

Also OEM shop manuals are available at marineengine.com

 

[Kevin W]

Re: fix the Mercury or Johnson

My BIL is most definately my new Fishin buddy.

I have seen the parts breakdown but my engine is a manual tilt and the Shock has seen better days.

i was planning on taking it apart but was not sure if it is Gas charged or spring loaded etc..

 

[rogerwa]

Re: fix the Mercury or Johnson

Did you have insurance?? Doesn't that cover this sort of tragedy?

 

[Kevin W]

Re: fix the Mercury or Johnson

Did you have insurance?? Doesn't that cover this sort of tragedy?

It most likely insurance would cover it if i had it...but i don't.
maybe i should get some.

I also have an update on my shock problem.
it was not the shock that was binding it was the top pin in the eyelet of the shock binding.
I removed the pin (it wasn't easy) and polished it and greased it up and the motor raises much better now.

 

[Kevin W]

Re: fix the Mercury or Johnson

Update:
the johnson is on the boat and 99% ready to go.
i had a small issue with the primer ...i broke one of the primer nipples when replacing the fuel lines.
I have to say this johnson is much easier to work on than the Merc.
its built tougher too.
I hope it runs better too.
all i need now is anti rock sonar...LOL

 

[papasage]

Re: fix the Mercury or Johnson

i have a merc. that might have a good ft. on it . the power head stops at half turn . don`t know anything else about it . would sell cheep as i don`t need it . got it in a trade . if you wer comming south anytime you could pick it up . think it is complkeat motor . would have menny good parts

 

[Kevin W]

Re: fix the Mercury or Johnson

i have a merc. that might have a good ft. on it . the power head stops at half turn . don`t know anything else about it . would sell cheep as i don`t need it . got it in a trade . if you wer comming south anytime you could pick it up . think it is complkeat motor . would have menny good parts

Thank you very much for the reply!!
If i did not get the Johnson going i would be much more interested.
I also would be more interested if you was not 1200 miles away.

I had a very successful day of reviving the 70hp Johnson
It actually sounds better than my 70hp Merc did.
I still need to pond test it but it runs good on Muffs and in a barrel
Thanks again for the reply.

 

[papasage]

Re: fix the Mercury or Johnson

they alwayes sound good on muffs . pull plugs and see if all plugs are firing . or lay hand on side of each cylinders and see if one is colder than the others .
if you ever come down this way let me know and i may still have the motor . got several i need to git rid of . i have 8 motors and 6 run good . have several old junks and a bunch of parts . they are taking up space in my shop storage room .

 

[Kevin W]

Re: fix the Mercury or Johnson

Well a bit of an update on the Johnson.
I took it for the water test ride today.
The only issue that came up was a low idle when cold.
once warm it ran like a top...even better than the Mercury did.
I would say i made a good choice to change over to the Johnson.
The Merc is for sale or still looking for parts to fix.