Not sure I understand carbs well enough!!

[lkaskel]

Hi Everyone,
I have a Husky 18 ton log splitter that has a Briggs 110412-0158-E1 engine on it. It may not be the original engine because it has a Yard Machine label on the rewind pull starter. I bought it used a few years ago and it has never run great but it does start every time and it runs well enough to split wood. The main issue is that it surges very dramatically. I decided to really look at it today. I checked the valve lash and it was close but I did adjust it with no change to the performance. I then took the air cleaner/housing off and ran it with a wide open carb. It ran great!!! Ok, so why? I started with installing the filter housing (no filter) and it did not run as well. Not awful but there was a difference. Now, what am I missing? I noticed that on the face of the carb there are 2 bolt holes for mounting the filter housing to the face (with a gasket) and 1 “passage” hole into the guts of the carb. With the housing installed it blocks that hole about ½ way. There is no passage into the housing. This hole is unfiltered to the atmosphere. Does that make sense? Is it possible that this setup is incorrect? Did the previous owner combine parts and he created this issue? Are there other reasons that the engine would run so great with no filter/housing but not so great when installed? The filter housing type and carb face example are shown below.

 

[Auto Doc's]

Hello L.,

That hole is supposed to get filtered air if it has the correct air filter. Your parts picture is the wrong one according to parts tree:

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The air cleaner housing should have a matching hole to the carburetor. The carburetor has to have an atmospheric balance vent to compensate for the difference of an external and internal atmospheric.

I have also seen housing gaskets that were wrong block this hole before, and the same thing would happen.

A couple of pictures of you actually assembly would greatly help figure out this situation.

 

[Scrubcadet10]

This is the O.E. base and gasket set up. how does it compare to yours?

 

[ILENGINE]

View attachment 72272 This is the O.E. base and gasket set up. how does it compare to yours?

The diagram also shows the one in the OP picture on another page of the IPL. I suspect that the carb has been replaced at one time. From a low vent style to the high vent style, and I suspect the OP has the low vent air cleaner base with the high vent carb, which don't work well together.

 

[Auto Doc's]

The diagram also shows the one in the OP picture on another page of the IPL. I suspect that the carb has been replaced at one time. From a low vent style to the high vent style, and I suspect the OP has the low vent air cleaner base with the high vent carb, which don't work well together.

One thing is for certain; they are choking off the air flow to the bowl vent from the sound of the situation.

I have run into this a couple of times with engine swap situations where parts were mixed up in the process.

 

[StarTech]

Using the model/type it looks like the hi rise cleaner base does not match the carburetor based on the image of the 693458 gasket. If the image of the carburetor is what the OP has it is not the 694112 carburetor as its setup is different. Now I am not to find an image of the 694112.

Now what Scrub imaged would be the correct flat panel just air filter base for the carburetor shown.

With that it appears that OP needs either 591306 or 697030 hi rise filter base.


But this is just a hunch so take this with a grain of salt.

 

[lkaskel]

Hi Everyone,
Thanks so much for your replies!! Here are some pics to help you understand this setup...

 

[lkaskel]

Using the model/type it looks like the hi rise cleaner base does not match the carburetor based on the image of the 693458 gasket. If the image of the carburetor is what the OP has it is not the 694112 carburetor as its setup is different. Now I am not to find an image of the 694112.

Now what Scrub imaged would be the correct flat panel just air filter base for the carburetor shown.

With that it appears that OP needs either 591306 or 697030 hi rise filter base.
View attachment 72273

But this is just a hunch so take this with a grain of salt.

You are correct that the filter base you show is what this engine has but it does not have the inside notch for the hole in question. The gasket at the top is one they used. I am assuming that I have mixed parts that do not work together. Let me know your thoughts once you see the pics I posted. Thanks soo much!!

 

[StarTech]

You definitely the air and gasket for the carb involved,

 

[Auto Doc's]

Maybe an Amazon or previous DIY repair attempt strikes again scenario. Gasket is correct but housing mount area is wrong.

The example that StarTech provided is what should be on this.