Dusty and Dirt

[SkidTracks]

Are any other Bobcat R-series owners having issues with dust and dirt as follows:
1) Under cab, dust and dirt covering most horizontal flat surfaces. Dust and dirt building up to 1-1/2" deep on floor pan; after only a few days of being cleaned and partial day usage.
2) Primary engine air filter requiring cleaning every few hours of use.
3) Exterior cab air filter requiring cleaning at twice a day, sometimes three times.
4) Interior cab air filter requiring cleaning daily or every other day.
5) Air plenum behind interior cab air filter randomly filling up with water. Even though drain flapper is not plugged. Shutting off A/C fan allows water to drain. Water splashing on to filter causing severe air restriction (aka minimal cab cooling).
6) Interior of cab being infiltrated with dust. Needing to be blown out with Leaf-blower.
7) A/C air vents showing dust build-up. Dust accumulating behind digital touch display and overhead panels on either side at front.

Never saw such an extreme level of dust and dirt problems with old Bobcat M-series.

R-series cab is supposed to be independent box (or chamber); unlike old M-series which semi-sealed against chassis (or frame). Which has me puzzled as to how so much dust is getting into cab.
R-series appears to have better sealing where hydraulic hoses for track motors go thru chassis. Leading to puzzle of, how dust and dirt are entering and building up as quickly and abundantly.


Chassis

Primary Engine Air Filter

Can't play basketball, but I can dribble an air filter.

Interior Cab Air Filter

 

[mrbb]

IMO< it sort of comes down to the environment your working in and there condition's,
I know in my area this yr has been extra dry and dusty, and things have gotten covered with dust in short order due to conditions

But if your machine itself, seems extra dusty, I would maybe suggest looking for HOW the dust is getting into places, are there any covers missing, or, gaps, dusts is getting thru, that maybe you could close up
I know I have seen some track model machine where the tracks would throw dirt into places, thus, also blowing dust into them

seen some so bad they damaged parts as dirt build up happened, or in winter time when they shoveled snow into same places and things froze, ice is powerful stuff and can bend metal,
I seen a guy with a CAT brand track machine, he had snow,(which melted) then turned ice built up in a pocket , and before he noticed it ended up bending the lift cylinders , as an example
so again, Id be looking at where the dust seems to travel and see if adding some sort of cover or?? could help you

 

[foton]

I assume that you have heard of newer bobcat loaders having air filter issues,it seems that they have engineered a fan to blow somehow thru a new part to seperate dirt and air before hitting the air intake to the air filter. seems like b s to me ,they put the intake cone in the wrong place and want to fix it on the cheap. to have you buy a kit to take care of thier f u . it seems to me.

 

[foton]

I believe there is a you tube video showing the installation of the kit.

 

[SkidTracks]

Follow-up:

Found what I believe is root cause of all dust and dirt in chassis, cab, engine air-filter, cab internal & external air filters.

T86 engine cooling fan is running opposite direction from normal. Air is being pulled through louvers of rear door, and exhausted out perforated grill located on top of engine area.

Checking another T86, the air is pulled through perforated grill located on top of engine area, and exhausted out rear door louvers.

Result is some of fan's intake (as reversed) air is being pulled from front part of chassis below cab area. With cab sitting on top of front part of chassis, a small amount of air is being pulled in through cab too.

Instead of cab having positive pressure as designed, cab has negative pressure with engine running. Put another way, cab is under a slight vacuum as well as front part of chassis. Resulting in dust and dirt being pulled into chassis and into cab.

Testing: With right cab window slightly open and a trash bag taped around window:
When engine is running - trash bag is partially collapsed and sucked up against right cab window (cab is under a vacuum).
With engine stopped - trash bag is puffed outwards from cab window (cab under pressure, as it should be).

T86 came this way brand new from dealer.

Now to get dealer to take problem seriously. On three previous occasions when I inquired and reported there being a severe dust and dirt problem; I was rebuffed with comments like: Dryer than usual. Usage of T86. R-series accumulate dust and dirt worse than M-series. Or some such. Even with pictures and video, there was rebuff as to problem.

After reading about engine fan operation in manual; I do wonder what long term effects on entire machine are going to be, once problem is fixed.

 

[SkidTracks]

Update to my post above (#5): T86's engine fan is running correct direction. Thus, fan is not connected up backwards or fan blades flipped. My confusion on fan comes from Bobcat having reversed air flow direction with newer models (T86) vs. older models (T870).

Still not sure what went wrong with checking cooling fan air flow of another T86.

Bobcat's new models suck air in through slats of rear door, across engine, and up into engine cooling fan above engine. Engine cooling fan then blows air upward, out through radiator and protective grill. Which is reverse of air flow of older models (T870).

New normal - In rear door and out protective grill.

Regardless, result of new normal air flow is as described above in my post above (#5). Cooling fan is also trying to pull air in through front chassis, upon which cab sits.

 

[SkidTracks]

I assume that you have heard of newer bobcat loaders having air filter issues,it seems that they have engineered a fan to blow somehow thru a new part to seperate dirt and air before hitting the air intake to the air filter. seems like b s to me ,they put the intake cone in the wrong place and want to fix it on the cheap. to have you buy a kit to take care of thier f u . it seems to me.

I agree. Engine air intake is located next to protective grill on top of engine compartment. Where some of dust and dirt entering chassis is blown by engine cooling fan upward through radiator and out protective grill. Engine air intake needs to be further away (isolated) from protective grill.

 

[SkidTracks]

After Bobcat failing to fix dust and dirt problem, and trying a couple of my own unsuccessful workarounds; only viable solution I came up with was to replace T86, which I did.

As a heads up: If you live/work in sometimes dusty area and are looking to buy a Bobcat T86, S86, T76, or S76 ** - make sure to test cab for air leaks and cab has positive pressure.

Checking for positive cab pressure: Plastic sheet (garbage bag) taped over a 1/2" cracked open window should blow outward from cab when engine cooling fan is turning (normal direction). Should bag collapse, be pulled inward to cab, cab is not pressurized and is under a slight vacuum.

Checking for air leaks into cab: Where dust and dirt is sucked in at, requires mechanics smoke machine or fake fog machine (often used on Halloween) and helper. Someone in cab watching for smoke / fog, and person moving smoke / fog machine around cab, staying clear of cab's external air filter intake. First place to check is by cab's headlights.

** I know of another T86 which had same dust and dirt problem. According to PPM air quality meter, air inside was dirty than outside. Like mine, dust and dirt which had been sucked in to cab had gotten into A/C ducting and vents, despite internal cab filter.

 

[fortworth-cowboy]

After Bobcat failing to fix dust and dirt problem, and trying a couple of my own unsuccessful workarounds; only viable solution I came up with was to replace T86, which I did.

As a heads up: If you live/work in sometimes dusty area and are looking to buy a Bobcat T86, S86, T76, or S76 ** - make sure to test cab for air leaks and cab has positive pressure.

Checking for positive cab pressure: Plastic sheet (garbage bag) taped over a 1/2" cracked open window should blow outward from cab when engine cooling fan is turning (normal direction). Should bag collapse, be pulled inward to cab, cab is not pressurized and is under a slight vacuum.

Checking for air leaks into cab: Where dust and dirt is sucked in at, requires mechanics smoke machine or fake fog machine (often used on Halloween) and helper. Someone in cab watching for smoke / fog, and person moving smoke / fog machine around cab, staying clear of cab's external air filter intake. First place to check is by cab's headlights.

** I know of another T86 which had same dust and dirt problem. According to PPM air quality meter, air inside was dirty than outside. Like mine, dust and dirt which had been sucked in to cab had gotten into A/C ducting and vents, despite internal cab filter.

I hate to tell you that, and I worked on these machine for a long time, the R-Series is garbage compare to the M-Series machines.
How many hours you have on your T86? We had big issues with machines passing the 500 hour mark.

 

[SkidTracks]

I hate to tell you that, and I worked on these machine for a long time, the R-Series is garbage compare to the M-Series machines.
How many hours you have on your T86? We had big issues with machines passing the 500 hour mark.

Hours got to roughly 110. Problem with dust and dirt was there from start. I just didn't know it till usage in dry weather. I inquired several times about problem, but dust and dirt problem was dismissed by dealer's people.

Took a while for me to connect dots as to cause. By design, Bobcat had reversed engine cooling fan air flow between M-series and R-series, without relocating fan. At first, I honestly thought dealer had installed Auto-reversing fan cooling option wrong, connecting hydraulic hoses backwards.

(see pic - fine arrows are my attempt to show how cab air is sucked down into chassis and pulled into engine area through chassis - fat arrows are Bobcat's showing main airflow of R-series)
(see video - fog in cab being sucked out into chassis, finally fog from cab being blown out grill above radiator)

Bobcat on their M-series talked about how they got engine cooling fan correct compared to their competitors. At one point, Bobcat joking about recognizing one their competitors brand by a dust blown Rooster tail. Ironically, Bobcat ended up reversing air flow, without moving cooling fan to back door, which resulted in R-series doing a Rooster tail. Bobcat's backdoor intake fins point at ground, their competitor's point toward sky.

To best I know, (being Bobcat would not converse with me), all large engine R-series (T86, T76, S86, S76) will suffer same dust and dirt cab infiltration problem. And there is no solution to dust and dirt problem, while front part of chassis has negative air pressure, resulting in cab having negative air pressure. (I did verify chassis and cab air pressure was negative with engine cooling fan running).