Penetrating oil

I've got some tough rusted nuts and bolts I am trying to bust loose on a 71 Evinrude 50hp long shaft, and trying to bust loose the engine from the exhaust shaft with little positive results ----- Ideas?.

This may be a losing deal for me.

I really do not know how long this outboard has been sitting in the weather, but I have to guess it's been a long time.

[Nomad55]

Love the foil on what is likely a blown fuse in #3 photo.

Your best bet is to use a little heat,plenty of your favorite penetrating oil and copious amounts of patience. Don't be in a hurry as this could take awhile but drilling and taping is not a pleasant experience. In tight spots I use old license plates to keep heat from delicate items. The plates bend and cut easily.

[Tim McCrain]

What I've had the best luck with is a combination of penetrating oil, heat and cool cycles and lots of patience. I'll apply penetrating oil liberally, let it soak in over night, heat the area the bolt threads into really well and let it cool, repeat oil, heat and cool, etc.

I've found that the number of bolts I break off is directly related to how patient I am, more patience equals fewer broken bolts.

Good luck!

Tim

[Straycat]

One word Kroil or 2 words Aero Kroil ...................

Nomad55 --- I thought someone would appreciate the foil, kind of reminds me of my youth and junk cars.

Straycat and Tim McCrain I will give both ideas a try.

One of the other issues I have is trying to get the engine case separated from the exhaust case. I've smacked it a few times with a drift and hammer but she just won't budge. Tried using a wood chisel between the the cases to see if that would split it but it still hangs on. Maybe a little heat would do it.
I guess I might have to get real aggressive with it and give it the ole smack down.

[Tim_Mattson]

Turn it Over!

Looks like a tough one,rusty bolts into the powerhead isn`t a good sign.
Looks to have overheated good a few times,not much paint left on the Head seam.
Time to turn it upside down and wait for gravity to help that penetrant.
Use something thicker with the Aero-Kroil alternated.It is runny and the Tri-Flow or Fluid-Film will corral it and keep it in the seam.Watch as you heat it and you`ll see rusty leach out of the bubbling gap.
Heat the block,cool the bolt with spray.....repeat as needed ,with a break or breaks as you are patient.
Also get the lower unit shaft moving south before moving to the powerhead seam.....you`ll need all bolts freed before that one will come apart.
Once you turn those until loose , lay it on it`s side so the weight of the powerhead is now going to help.
A prybar at the rear and another under the intake can be pried on and a quick yank on both will usually break that gasket seam,though if prying ,I`m doing it upright and on the stand or boat.
You`ll need to roll that block around as you heat and turn those head bolts if you are to save this engine......gasket wil be cooked by the time you get there if not already.
My Two word answer is Mapp Gas.........
Tim M

[ChuckB]

Les:
MAPP gas, not your typical propane torch. But... you have one of those dreaded electric shift lower units if it is a '71. Don't put a whole lot of $$ into that motor as parts and qualified techs to fix the old lowers are expensive and hard to find. I'd look for another 2 or 3 cylinder JonnyRude of '75 or later vintage.
ChuckB

Les:
MAPP gas, not your typical propane torch. But... you have one of those dreaded electric shift lower units if it is a '71. Don't put a whole lot of $$ into that motor as parts and qualified techs to fix the old lowers are expensive and hard to find. I'd look for another 2 or 3 cylinder JonnyRude of '75 or later vintage.
ChuckB

Of course that's what I really didn't want to hear Chuck but it is what it is.
Not ever owning an outboard it's all new to me and I really do appreciate all the great feed back.
Why MAPP gas -- what makes it the better choice?

I think at this point I will continue to mess around with the 50hp but have my eyes and ears open for a '75 and newer.

I wonder how many thought ----- boy is he in for a rude awaking about that '71 50hp.

...Why MAPP gas -- what makes it the better choice?

Much hotter flame.

[Brian]

Hey Les,

You may be in for quite an ordeal with an engine in that kind of shape. But in the end, its a battle of will, determination and complete suspension of common sense. It may cost you your family, your career and even body parts, but it can be done.

Everything above is very sound advice, but I'd like to add a couple pointers from hard won experience:

1.) Never even attempt to use an 'EZ-out' on an engine block. They are extremely hard but also brittle. Which means they snap off in the hole. You wind up having to remove the hole to get the EZ-Out, out.
2.) If all the above fails and you have to drill, try to find left handed drill bits. They cut in reverse and if the bolt/screw does start to loosen, often it will back right out with the drill.
3.) Further on drilling, if the head snaps off, try to file it a little flat if possible and strike a precisely aimed divot with a center punch. Start there with maybe a 1/8" bit, and progressively get larger.
4.) If you are at the point where the shaft of the bolt is gone and all that remains are threads in the grooves,... a) Pick out the threads with a dental pick, b) Tap new threads where you are, or c) Keep drilling and use a helicoil insert.

Well, that's all for now, gotta hobble back down to the on-ramp. Sometimes my son drives by and he'll throw me a pack of smokes. Just remember, every engine has its breaking point.

[Robby321]

Plus I would just about bet the driveshaft into the crankshaft is a corroded into one piece too. If that Leg don't come off, all is a wasted effort.

Engine pronounced DEAD --- sad face

Ok I gave up ----- after 5 days trying to get the head off (first -- with penetrating oils and heat ---- then using the hammer and wedges) I have thrown in the towel and and called it a lost cause. I did get the head off but the damage to the block was server. To bad because the piston sleeves where nice and smooth.
I will concentrate all my efforts on finding a better one. Now how would one make an anchor out of a 71' Evinrude 50hp.

[Lootas1]

You take the Evinrude to the scrap dealer and then, with the money you get for all that aluminum, you buy a good anchor. In Bellingham, we are fortunate to have the scrap deal right behind the Pacific Marine Exchange where you can get anchors both new and old. Sorry about your loss. I love my Evinrude 50.

[Captain Jack]

RE: Comparison of penetrating oils

Found this on one of the Jeep forums. Good stuff.

I have shamelessly copied this from another site:

*Don't forget the April 2007 "Machinist's Workshop" magazine comparison
test.*
**
*They arranged a subjective test of all the popular penetrants with
the control being the torque required to remove the nut from a
"scientifically rusted" environment.*
**

*Penetrating oil ..... Average load*

None ..................... 516 pounds
WD-40 .................. 238 pounds
PB Blaster ............. 214 pounds
Liquid Wrench ..... 127 pounds
Kano Kroil ............ 106 pounds
ATF-Acetone mix....53 pounds

*The ATF-Acetone mix was a "home brew" mix of 50% acetone - 50% automatic transmission fluid.*
*Note the "home brew" was better than any commercial product in this one
particular test. Our local machinist group mixed up a batch and we all now
use it with equally good results. Note also that "Liquid Wrench" is about
as good as "Kroil" for about 20% of the price. *

What is this? Replacing marketing hype and the way it has always been done with test data?

They didn't test spray silicone oil. I like it as a non gumming lube, and go ahead and use the same thing as penetrating oil.

Heat and quench works. For a time I worked in a brake shop. We salvaged many calipers with a broken bleed screw with what the owner called the heat wrench. It is much easier to reach for the torch before you bust something off.

Out in the field, a little gas may help. A good hammering does too. I usually give things a squirt of silicone and then hammer away.

Those are some impressive results.
I tried the heat and quench along with using PB and liquid wrench. I lubed and let it sit for a day then heat and quench and repeat. Then I used several wedges and tapped them until I felt strong resistance then sprayed, heated and quenched. This went on for several days until I finally got the head to open up to the point that I could get a saws-all (with about 1/2" of bolt showing between the head and block) in there and finished it off by cutting the bolts next to the head. I figured I could bust the bolts out of the head better with a drift then continue to bang at it with a hammer and wedges.
Well the damage had already been done to the block because a few of the wedges had dug into the block and left several deep groves all the way and into the cylinder.
So now it's time to look for another rebuild-able unit, after all I'm still working on the Tollycraft and it will be a long while before it's water ready and I can work on an outboard in my shop in the fall/winter months.
I can't wait to put in at Fernridge lake down here in Eugene.
I am currently working on replacing the transom then I will start on the hull, re-glassing and painting. The side rails and bow need fixing also and I am thinking about adding a cabin to it. So I've got alot to do before it's water ready.