Air Inlet Pipe Deformation?

[jcpawlak]

Question for you all regarding my B2650. Was snowblowing again today here in northern Michigan, just a few inches of light fluffy snow. About 15 degrees F. About 45 minutes in, and on my last pass down the driveway, all of a sudden I started blowing very black smoke out the exhaust and lost power. As soon as I backed off, the smoke disappeared and everything appeared to go back to normal/idle. I slowly resumed and things behaved normally for a short while but then again got the same smoke/power loss. So I eased it to its parking spot and started to take a look under the hood. It appeared to me that the air intake pipe was deformed/collapsed, and restricting incoming air flow. There was no obvious blockage that I could see, but with the engine running it definitely wasn't "round". After shutting the engine down, it appeared to go back to what I recall as being a more normal shape. I took pictures to try and show these two scenarios.

Am I on the right track here as a possible root cause of my issues, or way off base? It seems to me the lack of air would cause the engine bogging down and black smoke. Any reason why I would be seeing this deformation? I've run in colder temperatures than this and not had a problem before.

Also, is the air cleaner body supposed to be clamped down? Mine is just sitting semi-loose in the U-bracket.....but I honestly don't recall if that is how it has always been, or if maybe a clamp has fallen off somehow/sometime. Maybe this movement is causing the pipe collapsing?!?

Any thoughts/comments would be greatly appreciated. Happy to take more photos and provide more information if it would be useful.

-Jonathan

 

[85Hokie]

My first thought is that the air filter is clogged with snow or has become wet - thus creating a vacuum in the hose that is being collapsed.

Check that air filter - if it has an inner and outer - check them both

 

[JimDeL]

For the airway to collapse like that there must be a restriction (like a clogged air filter) in the intake stream. If the air filter isn't clogged, check for some other restriction in the line.

 

[North Idaho Wolfman]

Snow / moisture in the air filter.

 

[jcpawlak]

My first thought is that the air filter is clogged with snow or has become wet - thus creating a vacuum in the hose that is being collapsed.

Check that air filter - if it has an inner and outer - check them both

I can confirm you are correct. Even before seeing your message I went back out to further investigate and found some snow/ice on the air filter. No idea why it built up this time and not over the past several years, but sure enough it was there. So currently clearing all that out and will see if that solves the problem.

I also saw some documentation that I should remove the air pipe leading to the filter body (see diagram) during winter/snow. I've never done that before, and not had issues, but is that the recommended procedure to avoid this from occurring to begin with?

 

[jcpawlak]

For the airway to collapse like that there must be a restriction (like a clogged air filter) in the intake stream. If the air filter isn't clogged, check for some other restriction in the line.

You are spot on....some snow/ice had gotten in there. So weird that after so many years this is the first time I've experienced this happening.

 

[jcpawlak]

Snow / moisture in the air filter.

You nailed it.

 

[GreensvilleJay]

'weather related event'. Roll of the dice but this time engine was hot enough, moisture at dew point, cold air temperature... I found out why small airplanes have 'carb heaters' one winter day.......
BTW , you really don't 'need' an air filter in winter (hint: check EVERY gas powered snowblower ) !

 

[bird dogger]

Question for you all regarding my B2650. Was snowblowing again today here in northern Michigan, just a few inches of light fluffy snow. About 15 degrees F. About 45 minutes in, and on my last pass down the driveway, all of a sudden I started blowing very black smoke out the exhaust and lost power. As soon as I backed off, the smoke disappeared and everything appeared to go back to normal/idle. I slowly resumed and things behaved normally for a short while but then again got the same smoke/power loss. So I eased it to its parking spot and started to take a look under the hood. It appeared to me that the air intake pipe was deformed/collapsed, and restricting incoming air flow. There was no obvious blockage that I could see, but with the engine running it definitely wasn't "round". After shutting the engine down, it appeared to go back to what I recall as being a more normal shape. I took pictures to try and show these two scenarios.

Am I on the right track here as a possible root cause of my issues, or way off base? It seems to me the lack of air would cause the engine bogging down and black smoke. Any reason why I would be seeing this deformation? I've run in colder temperatures than this and not had a problem before.

Also, is the air cleaner body supposed to be clamped down? Mine is just sitting semi-loose in the U-bracket.....but I honestly don't recall if that is how it has always been, or if maybe a clamp has fallen off somehow/sometime. Maybe this movement is causing the pipe collapsing?!?

Any thoughts/comments would be greatly appreciated. Happy to take more photos and provide more information if it would be useful.

-Jonathan

Hey Jonathan,
Here's my solution for my B2650 operating in our cold North Dakota weather. I don't have the front mount snowblower but had a few other issues with operating in temps near and well below zero. I make these Weather Front Kits for our B2650 and some other kubota models as well. (Happy reading )

An unintended benefit that I wasn't aware of at the time (since I use a 3 pt blower) is that the covers seem to all but eliminate the snow being sucked into the air intake and air filters. Here's one user's comments and pics of his B2650 having the same issues as you:
Air Filter Clogged With Snow

The covers are custom made to fit each model and require no tools or alterations to your tractor. Easy on/off in a minute or two. If interested in a set.....start a conversation and I'd be happy to answer any questions. I try to keep a set on hand for some models for quick shipping.

Great tractor, by the way!!!!

David

PS If anybody is interested in a set for their model....see the listing of models available in the Classified ad. If you don't see your model listed, we could work up a set of patterns for your particular model hopefully.

 

[nbryan]

Question for you all regarding my B2650. Was snowblowing again today here in northern Michigan, just a few inches of light fluffy snow. About 15 degrees F. About 45 minutes in, and on my last pass down the driveway, all of a sudden I started blowing very black smoke out the exhaust and lost power. As soon as I backed off, the smoke disappeared and everything appeared to go back to normal/idle. I slowly resumed and things behaved normally for a short while but then again got the same smoke/power loss. So I eased it to its parking spot and started to take a look under the hood. It appeared to me that the air intake pipe was deformed/collapsed, and restricting incoming air flow. There was no obvious blockage that I could see, but with the engine running it definitely wasn't "round". After shutting the engine down, it appeared to go back to what I recall as being a more normal shape. I took pictures to try and show these two scenarios.

Am I on the right track here as a possible root cause of my issues, or way off base? It seems to me the lack of air would cause the engine bogging down and black smoke. Any reason why I would be seeing this deformation? I've run in colder temperatures than this and not had a problem before.

Also, is the air cleaner body supposed to be clamped down? Mine is just sitting semi-loose in the U-bracket.....but I honestly don't recall if that is how it has always been, or if maybe a clamp has fallen off somehow/sometime. Maybe this movement is causing the pipe collapsing?!?

Any thoughts/comments would be greatly appreciated. Happy to take more photos and provide more information if it would be useful.

-Jonathan

It's snow and ice crystals getting sucked into the air filter housing.
My fix for 7 winters now hasn't failed:
Spring/Summer/Fall mode:

Winter Mode:

Tabs are cut and bent down to prevent any possible intake air restriction in winter mode.

 

[jcpawlak]

Hey Jonathan,
Here's my solution for my B2650 operating in our cold North Dakota weather. I don't have the front mount snowblower but had a few other issues with operating in temps near and well below zero. I make these Weather Front Kits for our B2650 and some other kubota models as well. (Happy reading )

An unintended benefit that I wasn't aware of at the time (since I use a 3 pt blower) is that the covers seem to all but eliminate the snow being sucked into the air intake and air filters. Here's one user's comments and pics of his B2650 having the same issues as you:
Air Filter Clogged With Snow

The covers are custom made to fit each model and require no tools or alterations to your tractor. Easy on/off in a minute or two. If interested in a set.....start a conversation and I'd be happy to answer any questions. I try to keep a set on hand for some models for quick shipping.

Great tractor, by the way!!!!

David

PS If anybody is interested in a set for their model....see the listing of models available in the Classified ad. If you don't see your model listed, we could work up a set of patterns for your particular model hopefully.

Those look great! And sound like they get the job done as well. I will ponder and let you know if I decide to go that route, appreciate the response and info

 

[jcpawlak]

It's snow and ice crystals getting sucked into the air filter housing.
My fix for 7 winters now hasn't failed:
Spring/Summer/Fall mode:
View attachment 120595

Winter Mode:
View attachment 120594
View attachment 120593
Tabs are cut and bent down to prevent any possible intake air restriction in winter mode.

Clever solution!

 

[DeepWoods]

I remove the intake during winter months, as well as installing a set of covers from bird dogger, and I no longer have any problems with ice build up in the filter, and the covers keep my tractor at the proper operating temp to keep me nice and warm in my cab. Unfortunately I have yet to use my tractor for blowing snow this year as we have only enough snow to cover the ground.

 

[Donystoy]

I remove the intake during winter months, as well as installing a set of covers from bird dogger, and I no longer have any problems with ice build up in the filter, and the covers keep my tractor at the proper operating temp to keep me nice and warm in my cab. Unfortunately I have yet to use my tractor for blowing snow this year as we have only enough snow to cover the ground.

Exactly! This is a well known issue when blowing snow. As soon as I installed the blower last winter I removed this pipe. Never had any issues. It is just part of my blower install and remove procedure.

 

[Anvil HB]

My 20 year old B2630 has a collapsed / deformed air intake going on 10 plus years. No snow...... just Fl. sand from mowing my grass and fields short. From day one I would blow out the air filter and the tractor at the end of the day. The collapsed area is at the bend in the tube going down to the filter, after an hour or more at times mowing I will get the smoke and power loss. Heat is the issue here, I cut the tube and installed a thin wall metal tube, back to mowing...

 

[SDT]

Snow / moisture in the air filter.

Bingo.

 

[SDT]

I can confirm you are correct. Even before seeing your message I went back out to further investigate and found some snow/ice on the air filter. No idea why it built up this time and not over the past several years, but sure enough it was there. So currently clearing all that out and will see if that solves the problem.

I also saw some documentation that I should remove the air pipe leading to the filter body (see diagram) during winter/snow. I've never done that before, and not had issues, but is that the recommended procedure to avoid this from occurring to begin with?

Double Bingo.

This is recommended when blowing snow and in all circumstances in cold weather for the B3350.