# Ariens 10M Lauson engines



## motorhead64 (Dec 15, 2013)

These are my 2 Lauson First Series engines, the H45D and the H55A, all rebuilt, painted and ready for reinstall. I have decals to install and some minor touch-up needed because parts always seem to get dinged while awaiting assembly. Note the carbs are not repainted. The paint remaining on them will wear over time and not be replaced. Painted carburetors always seem to lose their paint in a nasty way. The new muffler hookup on the H55A was the closest I could come to original. The H55A must have had the old 12 volt starter at one time as it has the bulge in the blower housing and has a ringed flywheel. The H45D was pull only to start. Also shown is the new brass oil drain on the H45D and its original Gard.n.Yard nameplate indicating serial number 0609. MH


----------



## scipper77 (Dec 4, 2013)

So that is not a Tecumseh? I'm not familiar with Lauson.


----------



## WestminsterFJR (Dec 30, 2013)

Nice job, MH! I like the brass oil drain and would be interested in the parts list. I noticed that the Lauson labeled engines (1960 and 1961) has the thicker base compared to engines starting in 1962. 

I did some research on the Lauson / Tecumseh relationship. Tecumseh purchased Lauson in 1956 to help jump start its engine division. From 1956 thru 1961, their products were labeled as Lauson / Tecumseh to help associate the new Tecumseh engine brand with the well established Lauson marque. By 1962, the Tecumseh brand has gained enough momentum that the Lauson association was no longer required and faded into history.

So technically speaking, the 1960 and 1961 engines were Tecumseh's as well.


----------



## HCBPH (Mar 8, 2011)

*Lauson*

I've got a 7HP Lauson on an old blower in the shed. I had it running last year but shoulder isn't up to recoil starting it. Pretty much any part I needed, a Tecumseh worked fine. This one predates Tecumseh buying Lauson, so it has some age on it but it did run.


----------



## Ray 1962 10ML60 (Oct 14, 2011)

Looks great motorhead. Agree with you on the paint issue, I usually end up scrubbing it off all my carbs when I do a rebuild. Love the orig Ariens tag, they are tough to come by as the fall off over the years. Mine had a hole pinched in it and was wired to the handlebars when I found it. Just a thought, I put a ball valve on the end of that oil drain on mine, makes changing the oil a breeze. No drips till you open the valve.


----------



## motorhead64 (Dec 15, 2013)

The Lauson records are all but gone. Enthusiasts have managed to cobble together bits and pieces. Lauson claimed to be the oldest engine manufacturer in the country. When it was bought out by Tecumseh, its L head engines were adapted and used for Tecumseh's duration. However, the H45 was short lived as was the H55. They had engine-driven oil pumps in the sump...quickly replaced by "dippers" that splash lubricated. Not exactly an improvement there. The decals for the earliest Tecumseh owned engines said "Lauson-Tecumseh." The engine instruction label appears to be a carryover from Lauson, too. I was surprised when I did my valve jobs, the valves had pins that transversed the valve stems instead of the flat, washer-style keepers of today. I replaced the valves with modern (Tecumseh) valves with modern keepers. MH


----------



## WestminsterFJR (Dec 30, 2013)

MH, were you able to get reproduced decals of the "Lauson-Tecumseh" label?


----------



## db130 (Feb 16, 2013)

The thicker base of the Lauson engines would explain why my 10ML has longer studs than my other Ariens.


----------



## motorhead64 (Dec 15, 2013)

Lauson-Tecumseh decals are available on the Bay...even with your choice of horsepower as per originals. They are self adhesive type. I've had good luck with them on my outboard restorations. I search on the Bay "Lauson engine parts." MH


----------



## WestminsterFJR (Dec 30, 2013)

motorhead64 said:


> However, the H45 was short lived as was the H55. They had engine-driven oil pumps in the sump...quickly replaced by "dippers" that splash lubricated.


MH, Is the oil pump driven by a gear internally? Any maintenance or servicing required? How would I know if mine fails, besides overheating? What are the pros/cons compared to the dipper design?


----------



## motorhead64 (Dec 15, 2013)

The pump runs of a gear on the camshaft and provides pressurized lube to the rod bearing, top main bearing and camshaft bearings. It is a positive displacement pump that is submerged in oil. There is no maintenance available since it is internal. When it fails, you only have whatever lube that the crankshaft journal splashing around provides. How long the bearings would hold up under that are anyone's guess. The advantage of pressurized lubrication is that it directs the oil where it is needed. Tecumseh discontinued the pump shortly after taking the reigns from Lauson, probably for cost savings. MH


----------



## mtd1024 (Feb 2, 2014)

motorhead64 said:


> The pump runs of a gear on the camshaft and provides pressurized lube to the rod bearing, top main bearing and camshaft bearings. It is a positive displacement pump that is submerged in oil. There is no maintenance available since it is internal. When it fails, you only have whatever lube that the crankshaft journal splashing around provides. How long the bearings would hold up under that are anyone's guess. The advantage of pressurized lubrication is that it directs the oil where it is needed. Tecumseh discontinued the pump shortly after taking the reigns from Lauson, probably for cost savings. MH


Did the Lawson engine have replaceable rod bearings?


----------



## motorhead64 (Dec 15, 2013)

Neither of mine...H45D or H55D have replaceable rod bearings. They are an integrated part of the connecting rod/cap assembly. MH


----------

