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Discussion Starter #1
I picked up a 80s sears snowblower to fix up and the last thing is to get it running good. Its got an 8hp tec and it will fire up and run but dies once it runs out of initial prime. If I pump the primer it will keep running. I have completely cleaned the carb. I ran some safety wire down the passages an everything is free now. I replaced the fuel line. There is no in line fuel filter and the in tank filter is clear. If I hit the bowl drain I get a nice stream of fuel. I haven't replaced the intake gasket which is a paper. Is this model particularly sensitive to not having a new intake gasket? all the Briggs I've ever worked on didn't seem to care along with the various S-200s I've fixed up over the years. So I'm open to ideas
Thanks
 

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Sounds like the holes in the bowl nut are clogged. Did you clean all 3 of them? There should be 1 big one on each side by the nut end and 1 tiny one on the thread end. Did you remember to open the adjusters out 1.5 turns on the bottom and 1 turn on the side?

Disassembly of Tecumseh (Lauson) Series 3 Carburetor 632334a
 

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Sounds like the holes in the bowl nut are clogged. Did you clean all 3 of them? There should be 1 big one on each side by the nut end and 1 tiny one on the thread end. Did you remember to open the adjusters out 1.5 turns on the bottom and 1 turn on the side?

Disassembly of Tecumseh (Lauson) Series 3 Carburetor 632334a

+1 on the nut. That small one near the top is hard to see and if it is clogged it will play havoc trying to setup up the carb.
 

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Discussion Starter #4
Its a different carb than that one. Its a Walbro with LME, 872, and 54 stamped on it.
I made sure when I screwed out the main jet that the air and fuel holes where all clear.

 

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Its a different carb than that one. Its a Walbro with LME, 872, and 54 stamped on it.
I made sure when I screwed out the main jet that the air and fuel holes where all clear.
I think there's an apples/oranges going on here. I have some carbs that look similar but not exactly the same so here goes based on what I suspect. Sounds like you looked at the main jet on the bottom of the bowl. There is a hole in there if you remove the main jet, that needs to be clear. On the top of the reservour above the float, there is a plug about the size of a dime. There's a small hole there by the edge so fuel can enter it. On the enter of that area, there are 3 tiny holes by the choke plate that connect to this area. The holes are the size of a piece of strand phone wire, those holes need to be clear and open. They should be on the right side as you look past the choke blade. IIRC, there's another hole on the bottom of the throat on the throttle blade side that connects to the main jet area.

Everything has to be free and open that supposed to be or it will not run correctly.

Hope that helps, good luck.
 

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Discussion Starter #6
Got the Beast going some today. I cut an intake gasket out of a 12 pack box then and it starts and runs but it won't hold a load very well at wot. I found a diagram and I think I have the float needle gasket in upside down. So I'm going to flip that and check my float level and gas flow throw the needle valve since its acting starved for fuel. It will run with part choke wot all the time loaded or unloaded. Though it leans to much and die without the choke. I've got a couple rabbit trails to chase tomorrow and I'll let everyone know what I find out.
 

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Carb

If you have a 8 HP Tecumseh, here goes. Needle valve seal is small white one. Take the old one out using something like a dentist pick and hook the hole in the seal to remove it. Easiest way I've found to put the new one in is to start it by hand with that little ridge going in first. I then use the butt end of a drill bit (the end that goes into the drill chuck) and use that to push the seal down into the opening. The Tecumseh manual tells how much drop to have on the float (can't swear to it but IIRC it's something under 1/4", but it's in the manual). I bought a drillbit that size just for that purpose. When you put the float on , looking from the bottom on the hinge side, the wire from the needle valve to the float, open end on the right (it does make a difference in some carbs). Start your rough adjustments at 1 turn open on the main jet and 1 1/2 on the intermediate jet.

Now for fun stuff. I found that two of the smaller engines I have don't like summer alcohol added gas. The 7 & 10 hp ones seem to tolerate it but the smaller ones don't like it. Consider getting some non-alcohol gas if you can to try if you still have issues with the governor, loss of power, etc.

Hope that helps.
 

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Discussion Starter #8
Right now I've got 100LL in it so there is no alcohol in the gas. Though I'm sure its more octane than this things ever seen before. I think part of the problem is the bowl isn't also aligned where it should be and thats not helping the issue. I haven't gotten back to it yet and won't till Sunday. Though hopefully then I can finish getting it sorted.

On the needle gasket I ended up using the low needle to push the seat back into place and that worked great.
 

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Bowl

I think part of the problem is the bowl isn't also aligned where it should be and thats not helping the issue.
Remember when putting the bowl onto the carb, the flat area aligns with the float hinge. When putting the highspeed jet in, turn it out a couple of turns first, put the main jet body and jet on, tighten it up then turn the jet in. Remember the main jet has a seat in there and if it's turned too tight when you install it, you may be pressing the jet against the seat before the bowl is tight to the housing.

Hope it all works out for you. Good luck.
 
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