Lauson T-600

[outbdnut2]

I just got my first Lauson, a T-600, for $30 at a garage sale. The recoil rope handle is missing and maybe the rope too, but I was able to turn the prop (with difficulty) and verify it is not seized up. The decals are all worn to be totally unreadable (probably bounced around the trunk of somebody’s car for years). At the rear of the tank, the casting has a chunk cracked off, but it appears this only affects its stability when set down horizontally on the ground. I know nothing about Lausons except what I found in The Old Outboard Book. OK – so I know it’s a 1948 or 1949 6 HP 4-stroke, air cooled, essentially a lawn mower engine on a outboard lower.

What oil should be in the crankcase? What is the recommended spark plug? Gap for plugs and points? I’ve learned they are known for overheating and damaging coils – I haven’t checked for spark or anything else yet. I learned the lever under the throttle lever is a choke. Before I tear into it, what else are these known for?
Thx,
Dave

• This topic was modified 5 years, 8 months ago by outbdnut2.

[outboardnut]

Don’t quote me but if I remember correctly You need the lower cowl to cool properly

[frankr]

Points 0.020″, plugs 0.025. Surprisingly, book says SAE 20 oil. Beginning in 1950. it says SAE 30.

[Buccaneer]

I have a newer, 1951 Lauson T-651 to start on some day. Not sure how similar the T-600
is, but if anyone has any digital owners or parts manuals for either, I’m sure we’d
be interested. 🙂

Prepare to be boarded!

[outbdnut2]

Thanks guys for the info on points, oil, etc……. and it does have the lower cowl.

Now all I need is time to get to it, and several other motors I’ve put a higher priority on, but I’m anxious to see and hear this old 4-stroke run, so the priority may move up some.
Dave

[jcrigan]

They had an earlier design where the parts did not interchange with the newer design. I think the did this in the first year of manufacture. Give us the serial number and we can tell what it is. Use non detergent oil on this. The sump holds about 20 ounces of oil. Sometimes the valves and valve guides have problems. I will try to scan the manual o n this model maybe tomorrow when i can make the time. I sent you a pm.

• This reply was modified 5 years, 8 months ago by jcrigan.
• This reply was modified 5 years, 8 months ago by jcrigan.
• This reply was modified 5 years, 8 months ago by jcrigan.

[outbdnut2]

The first digit of the serial number is either damaged, or it has been stamped over with another character. It looks like it originally may have been a 9, but I can’t tell for sure, as there is what looks like a short 1 or a T stamped over it – this may be a nick from damage, although it’s centered well over the original number, and there is no other damage anywhere near it.

Assuming the first digit is a 9, the serial number is 94910433. Note that first digit is not shaped exactly like the other 9 in the number.

Thanks for the PM – I sent you an E-mail.
Dave

[PM T2]

This is a really old thread, so this response may be useless but I’ll write it anyway.

I recently worked on a Lauson that is really a T-600 but is ID’s as an S-300 going by the tag on the motor. Irregardless, its a 6 horse twin. My motor was also stiff to turn over when acquired. Oiling the cylinder walls did not help. The problem turned out to be a seized upper crankshaft bearing. The bearing is shielded on both sides. Its been so long since this motor was used that the grease in the bearing solidified, making it impossible to turn. I removed the shield from one side of t he bearing and soaked it in lacquer thinner overnight to soften and wash out the dried up grease. The bearing spins easily now, and so does the engine. Might be something to check for if you haven’t done so nearly six years later, lol.

BTW my coil was no good due to the tar-like insulation either leaking out or being melted out. I replaced it with a John Deere pony engine coil that was available on Ebay. It works fine after altering the Eisemann laminations to make it fit. 

Best.
PM T2

He's livin' in his own private Idaho..... I hope to go out quietly in my sleep, like my grand-dad did..... and not screaming, like the passengers in his car...

1 user thanked author for this post.

outbdnut2

[seakaye12]

PM T2 wrote:

This is a really old thread, so this response may be useless but I’ll write it anyway.

I recently worked on a Lauson that is really a T-600 but is ID’s as an S-300 going by the tag on the motor. Irregardless, its a 6 horse twin. My motor was also stiff to turn over when acquired. Oiling the cylinder walls did not help. The problem turned out to be a seized upper crankshaft bearing. The bearing is shielded on both sides. Its been so long since this motor was used that the grease in the bearing solidified, making it impossible to turn. I removed the shield from one side of t he bearing and soaked it in lacquer thinner overnight to soften and wash out the dried up grease. The bearing spins easily now, and so does the engine. Might be something to check for if you haven’t done so nearly six years later, lol.

BTW my coil was no good due to the tar-like insulation either leaking out or being melted out. I replaced it with a John Deere pony engine coil that was available on Ebay. It works fine after altering the Eisemann laminations to make it fit. 

Best.
PM T2

Thanks for posting Chris.  I saw your pictures on FB.  There is only one variety of the “John Deere Pony Coil”?  I see them on e-bay and I should assume that the ones they have up there for sale listed as “John Deere Pony Coil” will be the one?

[Tubs]

 

Interesting that the bearing had shields. I would suspect that was a replacement at some point. You removing the other side or is that shield keeping oil out of the ignition? Don’t know anything about these.   

A "Boat House Repair" is one that done without having tools or the skills to do it properly.

[Author]

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