I have a wm7 Super 10. I can't find service or exploded view docs with speed. Therefore I am uncertain of what to expect when I gut the motor.
a detent to secure flywheel (crank nut) or does one use a strap wrench?
to remove lwr cowling does powerhead come off also? 3 studs per side under lwr cowling hold tiller bracket and 2 fasteners for fuel connector. is the power unit then free? is there a spline coupling between vertical drive shaft and crank at top or bottom> or what?
is water pump in vertical shaft housing or lower unit? it looks as if lower unit unbolts and slides out from vert shaft housing. Again, is there some splined coupling.
What is point gap at TDC? Plug Gap? What type of ignition wire do I buy to replace? Is there a fuel pump rebuild kit? Any merc point set drop in?
What SUPRISES should I be aware of before they happen???? firstname.lastname@example.org
Hi Roger. I will comment on your questions:
Is there a detent to secure flywheel (crank nut) or does one use a strap wrench? Use a strap wrench to hold the flywheel while unscrewing the nut. If the nut is the cog type that no wrench will fit, wrap a piece of web belt or leather belt around the nut and remove it with a pipewrench. Standard lefty-loosey thread. Then you will need a puller to pull the wheel. You can make one or buy one at Harbor Freight.
to remove lwr cowling does powerhead come off also? You should be able to unscrew the fasteners that hold the lower cowl and work it off of the powerhead. It was designed to be removed to clean or replace the plugs frequently, as we used a lot of 30 wt motor oil in those days and the plugs fowled often. That's the reason those lower cowls are so scarce - most people, me included, just left the things off and they eventually disappeared. 3 studs per side under lwr cowling hold tiller bracket and 2 fasteners for fuel connector. is the power unit then free? Yes. is there a spline coupling between vertical drive shaft and crank at top or bottom> or what? The driveshaft couples into the bottom of the crankshaft. NOTE: there is a square nut under the front of the powerhead that must be removed - find a socket that fits the thing. Notice how the aquare nut is "clocked" - must be in the same position on reassembly. Removing the sq nut and the 7/16" nut on the bottom of the tower allows the "foot" to be removed. Sometimes the water tube is stuck and must be levered a little to drop the foot. Be gentle,
is water pump in vertical shaft housing or lower unit? WP impeller: remove the prop; then you will need a spanner wrench to remove the disc that has two holes for the spanner pins. You can make a spanner out of a large crescent wrench or buy one a Harbor Freight that "might" be strong enough to do the job, but the crescent wrench is more likely to work. Those discs are usually a booger to remove - and NOTE - it is Left Hand Thread= Righty-loosey. looks as if lower unit unbolts and slides out from vert shaft housing. Yes, after you remove the sq nut and the small nut. Again, is there some splined coupling. Yes, see above.
What is point gap at TDC? When you get the wheel off I think the gap is marked on the mag plate. 0.018" I think but not sure. Plug Gap? 0.025 - 0.030".What type of ignition wire do I buy to replace? Real wire type at any auto parts store. NOT resistor wire. Is there a fuel pump rebuild kit? Yes, that is a common Mercury item still available at most dealers. Any merc point set drop in? Depending on the make of the mag points may or may not be available. Bendix are NLA. You may be able to carefully clean the points. Conds are available. Coils also. When you get to that point come back to us.
What SUPRISES should I be aware of before they happen???? Bendix coils are about $50 each. Phoelon are less. WP impellers are in the $30 range. Be sure the motor has decent compression, bearings, etc before investing in parts. Most probably you will end up with more in the motor than you can sell it for. Old motor restoration is mostly a labor of love, not profit. Good luck. email@example.com
I am not yet up to speed on the later Kiekhaefer made
(Mercury or Wizard) but I am into several. Big problem is the effect of decades of crud and corrosion...expect all fasteners to be difficult
and all parts to be joined more by C & C than by
nuts and bolts. Do a little research on line and
at your local library...mine has lots of old manuals
mostly wrong vintage or brand BUT you might find
a generic manual with Wizard or equivalant Mercury
model...a couple hints on removing flywheel...
1) do NOT screw the three screws beyond inner surface
of flywheel to avoid damage to coils
2) go to hardware store and buy a) 7/16 x 20 fine
thread nut and a 1/2" x 20 fine thread nut
Use them to protect threads on crankshaft (1/2)and
propshaft (7/16) I recently had a very difficult
flywheel...it finally released after I let some
solvent soak joint overnight, warmed up with
gentle use of torch and barely applied the puller
when flywheel came off with a "BANG"
3) Use your digital camera to take lots of pictures
and transfer to computer for review and help in
4) Flywheels go on DRY...no oil or lube at all AND
use torque wrench to refasten nut to spec...too
much and you risk splitting hub of flywheel...
ham fisted types please take note...also take
note...although a sharp rap on end of forcing
bolt of flywheel puller will usually cause
flywheel to release (and is an accepted proceedure) HAMMERING will only lead to battered
threads and a bent crankshaft.
5) Take your time and do it right or break
something hard to find and expensive.
Working on old outboards is different than working
on new ones...a careful patient approach is needed.
More than a few of my early projects suffered
until I learned this lesson and still do if I
get in too big a hurry.
First and foremost, thanks jw in dixie.
the previous owner raced this in some stock class that only allowed modifications such as polishing ports, balancing and other such sundry items. It hasn't been raced for 3 decades. It seems to have very good compression based on pull starter. Under the hood, it looks like it has/was maintained but has that oil film/dirt crud from storage.
I had problems getting my big hands between powerhead and cowling and wanted it removed for access. This is my first foray into Mercs. I have several old/older OMCs but I was lucky enough to purchase 2 which required nothing other than maintenance. The merc seems to be a simpler design than the omc (excluding that 2 cycles work in the same manner). I am relatively new to outboard restoration and I have learned I can disassemble with the best of 'em, it the reassembly that I struggle with but that is a lack of experience.
I didn't/don't want suprises the hard way. Can't beat a digital camera for documentation.
I have 3 issues: the engine swivel is frozen, the prop is locked on the shaft and the tilt pin has corroded. I recently acquired a 1909 seneca falls 12" lathe that I used a borax washing soda/water solution and 12 volt dc to remove rust (there wasn't much) that did an excellent job to the extent it would remove rust whereby frozen/stuck bolts and screws could be removed. I have concerns about doing it with dissimilar metals.
I may be better off parting it or selling it to someone who has more experience and a greater need than I do. I still have 2 OMCs to restore.
Thank you louis for your input.
(see above reply to jw)
In the last 55 years I have gained much "experience" and in many cases the lessons were hard ones. This is a relatively new arena for me and I wish to avoid hard lessons the best I can while I get experience.
This is my first merc, before it has been OMCs. When I was a kid we had a Merc powered runabout (1966) but my father worked on it. knowing what I know now, I would have paid more attention (Dad was Port engineer for a major marine transportation company).
Part availability is a concern. From my due diligence, this engine shares bases with 2 earlier mercs- one powerhead and one lower unit. I figure if I could look at electricals, I may have a better answer to the Go or No Go equation.
I have built several wooden boats and thought a hydro or speedster type boat and this engine might be fun (many state parks cap HP to 9.9)- more fun if I dropped 50 lbs.
Thanks for the help. I would email you but we have a desktop with "issues", one of which is it isn't opening microsoft programs.
Your first move is to diagnose the patient's illness(es)
1) turn engine over and listen and feel what is going on
with bearings and crankshaft...abnormal noise and
roughness may mean internal rust...and a teardown
2) check compression...a worn out motor or stuck rings
will give low readings...one you can fix the other
you can not..
3) stuck saddle pivot and prop indicate storage in a
damp location to me...what does appearance of motor
tell you? Good care or Not?
4) Water pump impellers never live long enough to
qualify for a pension...always factor in replacement
5) Coils frequently bad but not always...the difficult
flywheel when removed revealed like new looking
Bendix coils...don't buy coils or water pump impellers
until motor is back together and ready to run...if
it gets that far.
6) The later Kiekhaefers are not something I feel strong
on at this point. I am aware of your feeling that
these may be a little beyond your reach...if you
have little money in it and you work carefully
you can do it no harm...price out bearings,
seals and save all gaskets to use as patterns
On line, bearings can be significantly less expensive
than some less competitive suppliers...same bearings
can vary widely in price.
7) Worst case is you wind up with a pile of parts that
someone may need to finish theirs and recover a
portion of your out of pocket...Best case you
gain new skills, confidence and a runner!
I have 3 issues: the engine swivel is frozen; Look for a tension-adjustment screw on the saddle. Try loosening it and see if that releases the swivel.
Prop is stuck: lay the motor on its face and drip your favorite solvent into the gap between the prop and the shaft. I use a mix of ATF and diesel fuel. Put the propnut back on all but two threads, to leave a little slack, and while your helper holds the weight of the tower off of the floor by the prop blades, tap gently a few licks on the nut (or a temporary nut is better) and see if the thing comes loose. Don't go overboard and ruin the shaft threads. Some garage engineers rig a puller using clains and clips - think about how you might do that.
Tilt pin corroded; if it is too far gone you may have to cut it, drive the pieces out and find a good one.
Merc easier to work on than OMC? Well, some Merc guys will agree with you - most won't. And I doubt if any OMC guys would agree, but what do they know? They're so stuck on OMCs that they won't even look at a Merc. That's okay - more good ol' Mercs for us!
Here's a picture of the home-made spanner wrench for removing the impeller cover. Good luck. JW in Dixie
I have a Mercury KE7 powerhead torn down at moment...the
Mark 25 is a developed version. I also have a couple
KE4/Mark 7/KE7 gear cases torn down. They are less
developed version of KG7 gearcase. If you think worth while
I will set up and take pictures...
My email is LouD31M066@aol.com Let me know where to send
If someone can post on this site let me know.
There is a tension adjustment...have you released?
If that does not cure stuck pivot...
remove powerhead to access saddle and pivot
pin...if you are lucky inside of hollow pin is threaded
so you can use a bolt,nut and washer scheme to pull it
out...may need to assist with solvent and torch...
I have found at least one pin that defied removal so
I cut the pin with hack saw to remove saddle...not pretty
I believe you are correct on the damp storage issue. It was in the garage when I saw it and began barganing. Here is a link to pics of it which I took. I had not removed the cover so what you see is what I saw. No cleaning took place.
It had what I though was very good compression via pull cord. I removed plugs and top of piston had basic 2 cycle carbon on it but I could see what I thought was aluminum or steel. My guess is it was stored with oil cause it seemed gummy and not dry. It has not been run in 3 decades.
once i get the flywheel off, I believe I will know what to do.
On a note, I dont see how I can remove the lower cowing since the block sits on top of it and the vertical lower unit below. it looks as if it goes full circle. I have 2 more nuts to remove but on 3 of the previous 4, the enite stud came out- a typical to an auto stud, threaded on both ends. They must screw into the powerhead and if I am right, then what exactly holds the powerhead on? So confusing without a drawing(s).
I had to repair some other small internal combustion engines and bought a package of assorted gasket sheets. My father had a set of gasket punches I now have so I can make 90% of my gaskets. Do you know where I can find out which type of gasket material is used where on an engine?
I believe you had posted (or someone) that these wizards were a previous generation of mercs so the wouldn't outclass the current years models. I believe it was stated that the engine aspirated with a smaller carb and 4 reed plates rather than 8. Know how I could find the info to weak this up for higher HP and rpms? the seller said they balanced the pistons, flywheel and whatever they could/were allowed under that class he raced in.
thanks again. It is generous of you to share your experience to someone who is a neophyte. Hell, a man's gotta have a few hobbies....right?
I got to thinking....dangerous process...I have a
KF3 and a KF5 gearcase torn down AND they are same
layout except on a smaller scale as the KE4 thru KG? gearcase series and so for Wizard eguivalents
getting late will get back to this tomorrow.