'74 C160 Tecumseh engine tractor. Let's put it to use!

[oliver2-44 9,726]

Those 2 choke screws are different colors, me thinks someone has tinkered with that carb before you EB. Maybe the choke plate is upside down or even the wrong one. Seems like I’ve seen where the choke plate has a notch out for that little nubbie. 

Edited September 9, 2022 by oliver2-44

[Horse Newbie 7,066]

Perhaps the brass choke flap needs to be taken out and reinstalled with the flap “above” the nub … maybe the choke flap won’t open as far, but the engine should get enough air… and it would close all the way.

Edited September 9, 2022 by Horse Newbie

[ebinmaine 67,397]

6 hours ago, oliver2-44 said:

Those 2 chicken screws are different colors, me thinks someone has tinkered with that carb before you EB. Maybe the choke plate is upside down or even the wrong one. Seems like I’ve seen where the choke plate has a notch out for that little nubbie. 

 

Interesting little trinket of information isn't it?

I've seen other carburetors where the screws were distinctly two different colors because one rusted and the other one didn't. Don't know why that happens.

I am fairly sure that this is not the original carburetor for this engine because the color wasn't right.

I'll have to take a minute and check my other Tecumsehorse to see how that one looks.

[Handy Don 12,204]

9 hours ago, oliver2-44 said:

Seems like I’ve seen where the choke plate has a notch out for that little nubbie. 

I concur about the notch. I'm fairly sure the purpose of the opening in the body is to let the engine pull air through a fuel vaporizing passage so it needs clear access.

[ebinmaine 67,397]

On 9/9/2022 at 9:05 AM, Handy Don said:

opening in the body

This one?

 

 

Edited September 15, 2022 by ebinmaine

[ebinmaine 67,397]

@Handy Don

 

Also interesting about this particular carburetor is that I don't think it has any internal plunger.

It's obviously a very different shape from a Kohler carburetor but it's a much more simple design than a normal Tecumseh carburetor.  

 

It appears that the three holes behind the Welch plug are for additional air flow?

 

It's going to be a bit before I get time to mess with this thing but I'm looking forward to seeing if it runs better now that it's been cleaned out.  

[Handy Don 12,204]

7 hours ago, ebinmaine said:

This one?

Yes. 👍🙂

[ineedanother 1,369]

11 hours ago, ebinmaine said:

 

It appears that the three holes behind the Welch plug are for additional air flow?

 

I've never known drillings to be designed for anything other than fuel flow. 

[ebinmaine 67,397]

16 minutes ago, ineedanother said:

I've never known drillings to be designed for anything other than fuel flow. 

I'll get some better pics in a day or three. 

Interesting setup.   

Certainly could be drawing fuel up through the bowl.  

 

[Handy Don 12,204]

On 9/9/2022 at 9:13 PM, ineedanother said:

I've never known drillings to be designed for anything other than fuel flow. 

Some drillings that enter the main bore are there to detect high or low air pressure at different points in the airflow which then affects fuel flow.

Edited September 11, 2022 by Handy Don

[ineedanother 1,369]

1 minute ago, Handy Don said:

Some drillings that enter the main bore are there to create pressure or detect low pressure that affects fuel flow.

Interesting. I never knew that. It's a good day when I learn something new 

[ebinmaine 67,397]

@oliver2-44 @Horse Newbie @Handy Don

 

So those screws in the choke flapper .... I agree they've been out/replaced/moved/changed

 

This evening I spent a minute with this carb and discovered that the screws in the choke flap were moved at some point in the past. 

Why so I figure so?

As soon as I loosened the silver one the flapper moved. 

For the rusted looking screw I did the @Pullstart advised tighten slightly then loosen method.  

I got all 4 screws out so it can be cleaned better when I have more time.  

 

Now about the air holes/galleys behind the Welch plug...

there are 3 or 4.  At least one - I believe - was closed. Then another was pretty schmutzzy. 

I bit of itty-bitty wire helped.  

[Pullstart 62,831]

2 minutes ago, ebinmaine said:

schmutzzy. 

Hate when that happens!

[Jayzauto 89]

2 hours ago, ebinmaine said:

Now about the air holes/galleys behind the Welch plug...

there are 3 or 4. 

 

So those holes behind the plug are transfer ports..... Generally there will be 3 on most carbs.  If you look closely, there are usually located at the throttle plate, and they act as sort of an accelerator pump, because most of these carbs do not have that pump.  They are located just after the throttle plate when closed, so when the throttle is cracked, there will be fuel enrichment for accelerating up to high speed...will prevent a stumble when throttle opened.  they are tied into the circuit for low speed idle mixture.  That circuit is 'vented through the face of the throttle bore.... if you look head on at the carb, it's usually the smaller hole, with a small brass insert in it, on the same side as the welch plug.  So after I boil out a carb and clean those transfer ports, Replace the welch plug and spray carb cleaner through that vent..... Look through the carb at the throttle end, with the throttle open and you can verify 3 small streams of spray (the low speed jet should be installed).  Then your sure to be ready for action..

 

 

GLuck, Jay

[oliver2-44 9,726]

36 minutes ago, Jayzauto said:

 So after I boil out a carb

Not to steel EB’s thread, but share with us how you boil out a carb

[Jayzauto 89]

45 minutes ago, oliver2-44 said:

Not to steel EB’s thread, but share with us how you boil out a carb

 

 

Rite, sorry about the side track, wanted to explain the transfer ports..... And it's not exactly 'boiling it out', just a name i gave it.  It's actually just an ultrasonic cleaner.  But I scored a large one, 30 L ??  not sure exactly, but price was rite.  The guys at the shop call it a 'Hot Dog Cooker' because of the size, and the temps it runs at.   I normally use Pine Sol and water mix, 50/50, since it won't discolor the aluminum carbs.   Worx well, and its large enough to clean engine parts.

 

GLuck, Jay

[ebinmaine 67,397]

6 hours ago, Jayzauto said:

That circuit is 'vented through the face of the throttle bore.... if you look head on at the carb, it's usually the smaller hole, with a small brass insert in it, on the same side as the welch plug

 

On 9/9/2022 at 9:26 AM, ebinmaine said:

This one?

 

 

 

Jay is that the vent hole?

 

Doesn't appear to be a hole at all though I wondered if there should be.  

[Oldskool 6,643]

I don't want to hi-jack your thread but while you are on the subject or carburetors..........Is there a welch plug assortment pack worth buying? One that won't leave the biggest part of it unused.

[ebinmaine 67,397]

7 hours ago, oliver2-44 said:

Not to steel EB’s thread, 

 

17 minutes ago, Oldskool said:

I don't want to hi-jack your thread

 

Folks, don't ever get worried about hijacking or stealing or borrowing one of my threads. If the information you're looking for is related to the subject directly, that's awesome.

Both of the above inquiries certainly are.

 

Even if it's a little sideways or off topic, the entertainment value is often worth it.

 

 

19 minutes ago, Oldskool said:

.....Is there a welch plug assortment pack worth buying? One that won't leave the biggest part of it unused

 

I appreciate you bringing this up in particular because I was wondering the same thing and forgot to post it. 

[ineedanother 1,369]

13 hours ago, Oldskool said:

I don't want to hi-jack your thread but while you are on the subject or carburetors..........Is there a welch plug assortment pack worth buying? One that won't leave the biggest part of it unused.

Thanks for your spirit @ebinmaine, that's one of the things I really like about this group  I'm not an expert but I've rebuilt many carbs. @Oldskool, I would say no, assortments will just clutter your shop with plugs you'll never use unless you do it for a living. Most of the Walbros that I've rebuilt use (2) 3/8" plugs and that's it. You can get packs of 10 for less than $15. Cross-reference part numbers to verify what you're getting but Kohler is pretty standard more often than not.

 

I would say too, there's no need to get "kits" for removal and installation either unless you're working with 2s and a bunch of specialty plugs. Waste of money. Removal is easy by drilling or driving an awl in and a drift punch works just fine for setting round plugs. A 4" or 6" vise and a headlamp are better investments, as is an ultrasonic cleaner if you can justify one with enough usage. 

[ebinmaine 67,397]

2 minutes ago, ineedanother said:

ultrasonic cleaner if you can justify one with enough usage. 

Yeeesh. 

I been mulling that one over too.   

 

[ineedanother 1,369]

9 minutes ago, ebinmaine said:

Yeeesh. 

I been mulling that one over too.   

 

Jewelry cleaner for BBT that you just might keep in your shop? 

[ebinmaine 67,397]

4 minutes ago, ineedanother said:

Jewelry cleaner for BBT that you just might keep in your shop? 

In principle it's an interesting idea.  

Fact is she owns near zero jewelry so I'd have to word the "gift purchase" carefully.  

😅

[ineedanother 1,369]

1 minute ago, ebinmaine said:

In principle it's an interesting idea.  

Fact is she owns near zero jewelry so I'd have to word the "gift purchase" carefully.  

😅

 Sound like my wife and that somebody needs to come up with plan B 

[Handy Don 12,204]

My wife is a calligrapher and I've been slowly introducing the idea of an ultrasonic pen cleaner but getting nowhere.

Maybe I should go the other way--I'll get this shop gadget that you can use to clean your pens quickly!

Edited September 16, 2022 by Handy Don