Tecumseh hs5

[Joe90]

I know nothing about these engines. So here is my question. The engine I am looking at has a square exhaust, is it easy to put the old style round exhaust on this engine?
I remember my old original engine had the exhaust port on the left and the carb port on the right. On the engine that I am looking at it is opposite. Can this be flipped or exchange with diffrent manifold and exhaust? Thanks Joe

 

[capguncowboy]

H engines (H25, H30, H35, H50) have the exhaust on the left. HS engines (HS40, HS50) have it on the right. It's easy to change out the muffler/exhaust. you just have to make sure the one you're trying to put on is compatible with that engine.

 

[markus]

You cannot swap the intake/exhaust around, your stuck with it in the configuration that it is. On an HS50, if the engine is roughly 1974 or newer, there will not be threads in the in the exhaust port to install the 45 degree street elbow and round thread in muffler like what was the standard in the late 60's on mini bikes.

Tecumseh did make a threaded flange, its part number 730165. They of course are NLA and the ones that are floating around for HS50's run about $40 for NOS and Repro. The HS50 also has a larger port and even the flange is the larger thread so if you did go that route, you would need a 3/4 male to 1/2 female 45 degree street elbow to use the small round screw in muff. It would of course have to exit out the right side, which they did in fact do on HS40's before they came up with the bolt on headers.

 

[Joe90]

Thank you for the information it is very helpful. Might pt the newer HS on my 68 fox trail bug. Still looking for the correct engine but for the moment.....

 

[markus]

Thank you for the information it is very helpful. Might pt the newer HS on my 68 fox trail bug. Still looking for the correct engine but for the moment.....

Well, since you mention trail bug, fox actually used a box muffler on those with an angled round tube outlet. Probably worked with the chrome accessory extension pipe they had on the campus bikes. That could be replicated pretty inexpensively, those rear exit muffs are still available new, and would just have to have a short piece of tubing brazed or welded on the outlet.

Heres about he best shot I can find of that muffler:

the thread with more pics of that bike:
http://www.oldminibikes.com/forum/mini-bike-discussion/87232-fox-survivor-barn.html

 

[Davis]

Well, since you mention trail bug, fox actually used a box muffler on those with an angled round tube outlet. Probably worked with the chrome accessory extension pipe they had on the campus bikes. That could be replicated pretty inexpensively, those rear exit muffs are still available new, and would just have to have a short piece of tubing brazed or welded on the outlet.

Heres about he best shot I can find of that muffler:

the thread with more pics of that bike:
http://www.oldminibikes.com/forum/mini-bike-discussion/87232-fox-survivor-barn.html

So in 1968 Tecumseh made two different h35 motors mine is an original lighted h35 off of my bonanza bc1200 it has a 5/8 keyed untapped shaft and my exaust is on the left side of the carb.

 

[markus]

So in 1968 Tecumseh made two different h35 motors mine is an original lighted h35 off of my bonanza bc1200 it has a 5/8 keyed untapped shaft and my exaust is on the left side of the carb. [/url]

Yes they made 2 different versions of the H35, side and rear exhaust-both on output side of engine.....Neither of which we are discussing in this thread though :wink: We are talking about HS engines, the HS40 was introduced for the 1968 model year, exhaust port on right side of engine. the bike pictured has a first version HS40 on it.