Tinkering with a 10 HP Tec snowblower engine

[MFDAC]

My MF8E has had several engine swaps through the years. Around 10 years ago I put a 10 HP Tecumseh on it that came off a monstrous snow blower . It runs great, BUT the carb has always leaked when the engine isn't running. No fuel shutoff so pinching a fuel line was the shutoff. Several new carb needles and a new float never fixed it.

Mt question is, since this carb has that primer bulb to fill the float bowl, can I just plug off the primer port on the carb and eliminate that darn setup completely? I'll try to make time to pull the blower housing off tomorrow night to look at how that is plumbed in to the fuel line. I can't help thinking that there's a leak in the primer setup that just lets fuel keep flowing into the carb. I don't know if that is the only vent to the float bowl either. On the "normal" carb there doesn't look to be anything different to vent the float bowl.

The carb pic shows the primer port on the left carb and a "normal" carb on the right. Then there's a pic of the primer hose hanging out of the engine and then a pic of the stuff I'm working on to get the old tractor running again. A new muffler setup being one of them.

Any advice is appreciated!

DAC

 

[Toomanytoys84]

I don't think it would matter if it was blocked off or not. Only one good way to find out.

I swear the only Tecumseh I had with a primer bulb didn't have a choke?

 

[MFDAC]

I don't think it would matter if it was blocked off or not. Only one good way to find out.

I swear the only Tecumseh I had with a primer bulb didn't have a choke?

Thanks Aaron. This engine came off a walk behind Craftsman snow blower. It had not been modified. I will just give it a shot!. Got plenty to do first.

DAC

 

[MFDAC]

I have had no luck doing searches on the numbers from the blower housing in an attempt to know what I have. I'm calling this engine a 10 hp because the snow blower I took it off of had 10 hp stickers on it. If an HH100 looks similar to an HH120, this engine is a whole different type. Nothing fancy with the primer bulb setup, so I will just eliminate it and try it.

Would anyone know this number? 143-686102 SER 8157D

Here's a couple more pics.

DAC

 

[ol' stonebreaker]

I believe the primer bulb just shoots a shot of air into the float chamber which forces gas up through the main jet into the venturi.
Mike

 

[KennyP]

I have had no luck doing searches on the numbers from the blower housing in an attempt to know what I have. I'm calling this engine a 10 hp because the snow blower I took it off of had 10 hp stickers on it. If an HH100 looks similar to an HH120, this engine is a whole different type. Nothing fancy with the primer bulb setup, so I will just eliminate it and try it.

Would anyone know this number? 143-686102 SER 8157D

Here's a couple more pics.

DAC

I recognized that #. It's Sears to Tecumseh. Here's what the manual shows:


Here's the whole page:

 

[Jazz]

I’m no help. I have the 11hp Tecumseh on my 16 year old Craftsman blower and only issue ever was electric starter broke. Those starters are not up to starting engine at -30
I keep snowblower and tractor blower unit in garage during winter since that episode

 

[MFDAC]

I believe the primer bulb just shoots a shot of air into the float chamber which forces gas up through the main jet into the venturi.
Mike

I appreciate the response, Mike. It does look like that is about all that bulb can do since it doesn't have any way to pump fuel. When I was using this tractor regularly it wasn't very often I even used the primer. I would just un-clip the little pair of vice-grips that I used for a fuel shutoff and use the electric starter!

I recognized that #. It's Sears to Tecumseh. Here's what the manual shows:
View attachment 7039

Here's the whole page:
View attachment 7040

Thanks Kenny, HM100, that is the kind of info I was looking for, now hoping to find out a rough age of the engine. Yes this engine was on a Craftsman snow blower. 32" if I remember right.

I’m no help. I have the 11hp Tecumseh on my 16 year old Craftsman blower and only issue ever was electric starter broke. Those starters are not up to starting engine at -30
I keep snowblower and tractor blower unit in garage during winter since that episode

Thanks for commenting Jazz. We approach -30 here but not very often. This may be the winter though since summer was cooler than normal! We had -28 for several days 2 years ago, along with a very high water table---nearly ground level. It froze, heaved up and broke up the concrete patio.
I had that snowblower for about 20 years and it beat the holy heck out of me when I would use it. The axle was "locked" so turning that thing was brutal! I like using a plow blade much better here where the wind never seems to stop. I have never tried the snow blower for my MF12G. My equipment is in the shop too.

DAC

 

[MFDAC]

I got to work on a different air cleaner setup today, but only after helping my wife get a bunch of her halloween teacher supplies down out of the loft so she could go through them. Thankfully she threw a good amount of it in the garbage!

Since this is a snow blower engine it never had an air cleaner on it. When I put the engine on the MF8E, I rigged up an old K&N race car breather for that purpose. I had some extra parts after the engine swap on the MF12G so I used it to build a "real" air cleaner setup. Not real pretty but functional at least. Now it uses the same paper elements as the 12G.

I also ordered a couple of control lever/cable setups, some fuel line and shutoff valves. Also got a little tool coming that's supposed to make bending the "double 90*" bends easier. I think it was 5 bucks so what the heck.

Nice afternoon out in the shop with a race on TV.

Pics of the air cleaner setup being mocked up.

DAC

 

[ol' stonebreaker]

I think that air filter will go a looong time before needing replacement!!
Mike

 

[MFDAC]

I think that air filter will go a looong time before needing replacement!!
Mike

That setup is just the stock air cleaner for an HH120 Tecumseh engine so it's cheap and easy to get filters for. I'm going to lower it a ways, a 4" nipple is all I had laying around the shop. Need to make a hardware store run. I just don't want it TOO close to the tire.

DAC

 

[MFDAC]

I worked on the exhaust a bit today. The reason I'm going through all this work is that the stock muffler blows straight at the grill and right headlight-first picture shows how that is affecting the inside of the hood and grill. I have the wire harness for the Tec engine to use the headlights, but didn't want to install it until these problems were fixed.



I built a flange for the exhaust port today, to give something to work with for routing and attaching a muffler that exits outside of the hood area.
I didn't like the idea of it just being black pipe all the way but I may have to use a black pipe 90* elbow, didn't get that far yet.



I forgot to take a pic after cleaning up and de-burring the inside of the pipe. Welding both sides partially was needed as the allen head bolt barely have clearance as it is.



It's probably time to take the homemade hydraulics off and use the original lift lever, possibly to adapt a fairly heavy duty craftsman blade I have laying out back. The lift lever needs a bit of welding but should bolt right back in.
No original MF8E parts will be harmed during this, I just need to make it more useful since there's no way for restoration.



Now tomorrow I go on call at work for a week so there may not be much progress.

Thanks, DAC

 

[ol' stonebreaker]

With intake tube made of black pipe I hope you have some sort of brace to support it near the air filter housing. With that much weight you may wind up with a broken carb. Might be best to find a lower radiator hose the right dia to fit over the pipe and a right angle molded in it. The exhaust probably will need bracing too.
Mike