"New" '57 Lark Update w/pics

[Mas]

Hi,

Things are going well with removal and cleaning. I was able to free up the starter motor armature, clean up the commutator, clean the bearings and shaft. I put it all back together...and it works! But, not strong enough! The starter will easily turn the motor with the plugs removed..but not the other way around. Hopefully a weak battery is the issue!

I dropped the LU from the leg to get an inspection done & some cleaning. I feared the worse realizing the leg was submerged in a 55 gal drum for years. My hopes increased when ALL bolts came out easily and the drive shaft and water tube just slid out! This seemed beyond belief. I expected several snapped bolts, a seized shaft in the crank, and a water tube giving me fits! None of these reared its ugly head. The shaft seemed brand new with minor wear and cleaned up nice with a shine using WD 40. The exhaust cavity and pump also cleaned easily. The impeller has taken a set and will need to be replaced...as always expected. The drive shaft pinion splines were perfect with no rust. Though I have not disassembled the gearcase, this gives me hope that it is not a bucket of rust.

It took a bit of doing to pop the flywheel off...but I got it. I now know why I do not have spark in at least one cylinder...toasted coil. The other coil looks to have been replaced recently. Maybe just cleaning the points will get one cylinder to fire. Anybody know a replacement part number for the coil and where it can be had? Hopefully I just need one.

Anyway...all is moving forward and this motor still has hope.

See pics below,

Mas

Drive shaft crank spline

Drive shaft pinion gear spline

LU cleaned up

Pump impeller plate

Pump impeller

Coils

 

[1946Zephyr]

Re: "New" '57 Lark Update w/pics

Yea, things look pretty good. Hopefully the inside of the gearcase looks good

 

[samo_ott]

Re: "New" '57 Lark Update w/pics

Looks good. That LU looks the same as my '54 25hp. I believe they're the same.

The coils are a dime a dozen. Any OMC dealer or after market place will have em. iBoats should have em. vintageoutboard.com, etc.

 

[lindy46]

Re: "New" '57 Lark Update w/pics

Coils maybe not a dime a dozen - more like $15-$20 apiece, but they were the same from early '50s thru mid '70s. No problem finding them - check Ebay, they're always on there.

 

[tmcalavy]

Re: "New" '57 Lark Update w/pics

You can also get coils for a pretty good price right here in the Iboats store.

 

[Texasmark]

Re: "New" '57 Lark Update w/pics

Must have been used in fresh water and kept in a garage. Cannot believe the condition of the alum after all those years. The shaft is a no brainer as it is SS, but cast aluminum on an outboard is quite another. Looks like you got yourself a find and I wouldn't call the job finished till you had a look at the lower unit and I would probably dismantle it and redo the seals and sealant.

Mark

 

[jay_merrill]

Re: "New" '57 Lark Update w/pics

I agree that the coils should be easy to find - iboats, OMC/BRP, Sierra, Sea-Way Marine, etc.



???

 

[Mas]

Re: "New" '57 Lark Update w/pics

Must have been used in fresh water and kept in a garage. Cannot believe the condition of the alum after all those years. The shaft is a no brainer as it is SS, but cast aluminum on an outboard is quite another. Looks like you got yourself a find and I wouldn't call the job finished till you had a look at the lower unit and I would probably dismantle it and redo the seals and sealant.

Mark

Believe me...I'm a bit baffled because the motor was not in a garage...but left outside in a 55 gal drum for years sitting in rusty water. Before I spruced up the outside with SOS pads, the entire leg & LU looked exactly like the prop in this photo. I basically thought I was buying a parts motor...go figure! I'm wondering if somehow the steel drum was acting like the weaker sacrificial metal and preserving the alloy aluminum. The transom clamp screws were totally eaten away! Or maybe a layer of oil on the top of the water's surface somehow helped??

Mas

Look at the prop in this pic:

 

[1946Zephyr]

Re: "New" '57 Lark Update w/pics

Wow, that is amazing, that the lower unit is in this good of shape. Have you torn down the gearcase yet? That's the part that has us all in suspense.

 

[Mas]

Re: "New" '57 Lark Update w/pics

I'll try to get to the gearcase tomorrow...I'll send some pics as soon as I get it opened.

Mas

 

[1946Zephyr]

Re: "New" '57 Lark Update w/pics

Looks good. That LU looks the same as my '54 25hp. I believe they're the same.

I think you're right Steve. Notice the channels that run along the rear perimeter of the housing? In your '54 (and prior years) these were the water tubes that went from the pump, to the powerhead. The upper water tube was more integrated in the leg and you only had to make sure the shaft was stabbed right. I believe it was 1955, when the tube connection was added to the impeller housing. In the older motors, 54 and older, you basically had to apply a bead of sealant to the seam of the lower unit and motor leg, to prevent water loss. I see in the later motors, like the one pictured here, they just left the mold unchanged.

 

[Mas]

Re: "New" '57 Lark Update w/pics

Should there have been any gaskets between the impeller plate, the pump housing, and the LU? Seems like there should have been...but none was to be found.

Also, there are two additional non-threaded holes around the same perimeter as the pump housing (say at 4:00 & 7:00 o'clock) that are plugged with crap. Are these to accommodate various pump housings...or are they part of the water passages and need to be cleared?

Mas

 

[1946Zephyr]

Re: "New" '57 Lark Update w/pics

Should there have been any gaskets between the impeller plate, the pump housing, and the LU? Seems like there should have been...but none was to be found.

No, actally there isn't. You could put a light coat of sealer where the housing sets on the stainless plate, to eliminate any water loss.

Also, there are two additional non-threaded holes around the same perimeter as the pump housing (say at 4:00 & 7:00 o'clock) that are plugged with crap. Are these to accommodate various pump housings...or are they part of the water passages and need to be cleared?

Mas

I'm not sure what those holes are for, but it would be a good idea to clean them out, just for good measure. They could possibly be for drainage. Your impeller housing only had three hold down screws?

 

[Mas]

Re: "New" '57 Lark Update w/pics

Yup...just three screws for the housing.

Mas

 

[Huron Angler]

Re: "New" '57 Lark Update w/pics

Good work, that's a nice surprise to find if you thought it to be a parts motor.

My girlfriend's grandfather has the same OB sitting in his basement that looks in about the same condition minus the 55 gallon drum treatment. Seems to have worked in this case pretty well though.

If it was in the thread I missed it, is that Lark a 35hp?

 

[Mas]

Re: "New" '57 Lark Update w/pics

Yup, 1957 35 hp lark.