Outdoor Power Equipment and Small Engines - tecumseh engine swap

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View Full Version : tecumseh engine swap


baffled bigtime
07-03-06, 09:02 PM
Is it possible to run a tucumseh 2 cycle engine in any position.I need to replace a verticle engine in an old outboard, and the only motor with the correct exhaust port that I could find was a snow blower motor that is set up to run as a horizonal at about a 15 degree angle.It has a diaphram carb.(S-200 maybe).will these carburetors work in any postion like a chain saw ,or does the diaphram plate have to be down .Please help , thank you.
P.S. The engine looks just like a verticle lawn mower engine,but has an angled intake manufold to position the carburetor at the 15 degree angle.I could add a plate at the carburetor and turn it 90 degrees to get the diaphram at the bottom,but would like to know if it will run with the carburetor on it's side. Is it designed to work in any position.
P.P.S. I just looked at an engine sellers site ,the engine I have appears to be a model THO98SA-1723 ,formerly HSK 635 . The carb on the one pictured at that site is a bowel (float) type .Mine is a diaphram type .


marbobj
07-04-06, 12:12 PM
Baffled B:

To see if the engine would start and run in the vertical position would be simple enough. Start it and tilt it. The internal dynamics of the two engines are probably very similar and obviously lubrication of components wouldn't likely be an issue.

However you could run into problems in application design and component support. If both applications were asking the engine to do nearly the same thing with similar output curves (torque and horsepower relative to rpms) the cross application may work.

The second hurdle may well be component support. Internally, the horzontal shaft engine may have different supports in terms of bearings and thrust washers as opposed to the vertical shaft engine. You may get it all put together and running and find out it doesn't last very long.

If you were going to save a significant amount of money with very little invested other than your time it would be interesting to do this as a project. However, if the main reason to do it was to save a little at the risk of losing a significant investment, I would have to call it iffy.

Hope this helps

baffled bigtime
07-04-06, 06:28 PM
Thank you for your reply.I got the engine and looked it over inside and out .It is identical to the original motor except for the carb.The original had the carb.(bowl type)mounted at the base of the engine.The new one has the carb mounted on the side of the block and has a plate at the base .While waiting for a reply here I mounted the old carb.by removing the base plate an installing the carb.I removed the engines original carb. and sealed the opening with an aluminium plate and gasket.The motor started on the third pull.I found the answer to my original question in one of the locked topics at the top of this web page (the diaphram carb. will run at any angle.I think I will find this site very helpful in the future , as I am always into endeavors that are just over my head .But that is how we learn.


cheese
07-05-06, 01:33 AM
Quote: "I am always into endeavors that are just over my head .But that is how we learn."----------you said it!

Glad you got it!

dave237
07-05-06, 02:33 AM
baffled bigtime,

I think you are on the right track. When you have it going on you have to continue, right? I will add this to Cheese's statement,... two cycles will function in almost any postion as long as the carb receives fuel which suppies lubrication to the crankcase. I suggest giving her a try and lets see your results... I think you're in the know here however, it's at your own risqeee.....!

God Bless,
Dave237

baffled bigtime
07-18-06, 07:07 PM
Well an update on my "snowblower outboard".I had a heck of a time with it.I got ahold of two bad carb's and spent a lot of time working with them .They would run the engine for a short time then quite working.I finally took a third carb apart and cleaned it with industrial solvent. I put it on the motor and it is running fine now.I took it out fishing Sunday an it purred right along .I only caught a few fish as I was testing the motor more than fishing .I was glad to get the outboard back in service as it had been idle in the garage for a few decades .Well thanks again for the help I recieved here .

cheese
07-18-06, 10:37 PM
Thanks for the update. Nice to work on something like that, and then go put it to use, huh?