# mini tiller - tillotson / tecumseh - won't run



## rubantin (Jun 24, 2007)

I just bought a troy-bilt mini tiller. It started and ran... but would kill when I opened the throttle. I bought a rebuild kit and rebuilt it this afternoon.

After the carb rebuild, I couldn't get the primer to prime... weird primer... one line and just sucks and blows...

Anyways before the rebuild i could see gas from the primer squirting in the top of the carb... 

So I poured a little fuel in the carb and cranked er up... ran for about 5 secs then died...

repeated the process about 10 times with the same results...

Took the carb back apart and blew air through it... some places i was not sure if I should get air out of...lol

BTW... the valve in the rebuild kit was the wrong size but everythig else matched up... it is a tillostson carb (HU)

Could the "lever" that pulls the needle valve that works with the diaphram be a different size in the kit and cause the valve not to seat proberrly... ok... here is my theory... the primer must use the valve as a check valve in order to prime the carb? i dunno... anyways if the needle valve was not seate properly would that cause the primer not to work...

HELP!!!


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## ajmartin (Oct 18, 2004)

*Same tiller and motor...*

That's quite the unit isn't it.... mine just won't idle... runs fast. Can you tell me if the throttle plate on your carburetor is "flat" or does it have a slight "bend" in the plate that allows air to pass by the low speed ports in the throttle body?


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## dawgpile (Apr 28, 2008)

rubantin... When you rebuilt the carb, did you clean the fine mesh screen under the pump diaphragm? I'm not sure if the rebuild kit came with a replacement for this. Obviously if it did and you replaced it, this is a moot point. Also, did you replace the diaphragms and their gaskets in the proper order? On the main diaphragm side, the gasket goes against the carb first, then the main diaphragm, then the cover/primer assy. On the other side of the carb which houses the pump diaphragm, the pump diaphragm goes against the carb first, then the gasket, then the cover.

I'm not sure why the needle valve would be the wrong size so I'd be inclined to put the original needle and control lever back in. Chances are good these are probably OK(this carb uses a rubber tipped needle). In other words, I'd just replace the two diaphragms and gaskets, and make sure the balance of the carb is clean, paying particular attention to the inlet screen.

Finally, have you examined the fuel lines and fuel filter in the tank to make sure they are OK. Pulling everything apart for the rebuild could have caused a crack or break in a dried out fuel line.

You can download a service manual for this carb from the Tillotson site here:
http://www.tillotson-fuelsystems.com/manuals.html

aj...I doubt the throttle plate is 'bent'. While I don't know this for a fact with this specific carb, I've never seen one that was. The plates are designed to close and the idle passage allows fuel to enter the carb. The service manual has great color photos to show fuel flow at various stages. If yours is bent, I'd suspect it was done either accidently or intentionally but I'd consider straightening it out. This could explain why yours won't idle. If the throttle plate isn't completely closing off the venturi, there would be little vacuum to suck fuel through the idle passage. Just a thought...

Let us know how you do...


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## ajmartin (Oct 18, 2004)

Thanks a lot for your comments Dawgpile, I also have never seen a "bent" throttle plate like this one, so I'm thinking (like you) that it must have been done intentionally at some point in the past. I removed the carburetor again yesterday and removed the throttle plate. I was waiting for responses to this forum to see if there was any "possibility" that the plate had been manufactured this way. Your comments support my "thinking" that the plate should be flat, so I'll try straightening it and see if it works.

It may however be a few days before I get around to it as the weather here in Manitoba, Canada is forecasted to be less than ideal for the next few days and I don't have a garage to work in. :-(

I'll keep you posted... thanks again.


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## ajmartin (Oct 18, 2004)

*It works...*

Hi again Dawgpile, well I flattened out the throttle plate and I can now get it to idle. I do however notice that this unit "smokes" a little more than I'd like it to. Recommendation is for 24:1 mixture but I read in one of your earlier posts that you suggested using Echo Power Blend oil at a 50:1 mixture for ALL 2 cycle engines. Do you think I should try that on this engine?

Sure appreciate all your help Dawgpile.


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## dawgpile (Apr 28, 2008)

Yes, I would recommend the Echo Power Blend. Just remember that you need to mix it with premium fuel, not regular. You should see some reduction in the smoking. Give it a try.

Glad to hear you got it running!


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