# Tecumseh AV520 Carburetor



## RKDOC (Jun 20, 2006)

This is on a Earthquake post hole drill. Tecumseh AV520 Spec 670127S DOM 8334. Does anyone know about this engines carburetor? I can make it run after I have pushed the primer button several times. It stops when the prime is burned out. This carb is different than any I have seen before. It has a diaphragm on the bottom and two adjuster screws on the side. I can not find any parts brake down or anything about it on the web. Does this have a main jet? will I destroy the diaphragm if I take it apart? I can not find any rebuild kits. I don't want to waste the guys time if it can't be fixed without a kit. Thanks for any help you can give me.


----------



## usmcgrunt (Sep 16, 2007)

These diaphragm carbs were typically used on old Toro S-200 snow blowers and others using small Tecumseh two strokes.Here is a link to the carb manual,if you don’t already have it.Pay attention to page-33. Some of these carbs have an “F” stamped near the carb throat and require the diaphragm,then gasket,then cover plate be installed.Without the “F”,the gasket,then diaphragm,then cover are installed.
Here is also a link to the carb kit and part number.Hope this helps.

http://www.barrettsmallengine.com/manual/tecumsehcarburetormanual.pdf

http://www.ebay.com/itm/TORO-TECUMS...301?pt=LH_DefaultDomain_0&hash=item4146725935


----------



## paulr44 (Oct 14, 2008)

1. If it has 2 mixture screws, those are the jets!
2. If you take it apart, no the diaphragm won't be damaged BUT the diagphragm gasket MAY tear during disassembly. The fuel inlet needle SEAT is brass, and requires a special socket to remove, which you can make yourself by grinding a "shoulder"/reduction/step around the *top lip *of the socket (thus making a thin-wall socket). I believe it's 9/32". If you don't grind the socket down, it won't seat fully and you'll probably round the corners off the jet assy.

To get any Tecumseh carb. kit, you FIRST have to get the carb. part number, then USE THAT like an engine SPEC number, and you'll get the IPL for it.

The kit may still say it on the backside as it did for years, if the carb. has an "F" stamped into the body, the diagphragm goes first, else it's diaphragm gasket goes on first as indicated in the IPL screenshot attached.

631720B is carb.
631893A is rebuild kit. (my distributor has roughly 250 on-hand...how many do you want!?) cost will prob. be about $11


----------



## paulr44 (Oct 14, 2008)

WE WERE TYPING AT THE SAME TIME!! ha ha ha!



usmcgrunt said:


> These diaphragm carbs were typically used on old Toro S-200 snow blowers and others using small Tecumseh two strokes.Here is a link to the carb manual,if you don’t already have it.Pay attention to page-33. Some of these carbs have an “F” stamped near the carb throat and require the diaphragm,then gasket,then cover plate be installed.Without the “F”,the gasket,then diaphragm,then cover are installed.
> Here is also a link to ther carb kit and part number.Hope this helps.
> 
> http://www.barrettsmallengine.com/manual/tecumsehcarburetormanual.pdf
> ...


----------



## usmcgrunt (Sep 16, 2007)

Hey Paul,good to SEE you again.Glad your business is doing well and appreciate it when you do stop by.


----------



## paulr44 (Oct 14, 2008)

usmcgrunt said:


> Hey Paul,good to SEE you again.Glad your business is doing well and appreciate it when you do stop by.


Thanks...been extremely busy lately, not much time to contribute here...will do so when possible.


----------



## RKDOC (Jun 20, 2006)

Thanks for the replies. The info and links were great an will help a lot. Thanks again.


----------

