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Discussion Starter · #1 ·
Just purchased a used 2011 f250 6.7 ... My blower motor runs find the vent controls seems to work but little air is making it to the Windshield on defrost and same when switched to heat.. Any ideals
 

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Just purchased a used 2011 f250 6.7 ... My blower motor runs find the vent controls seems to work but little air is making it to the Windshield on defrost and same when switched to heat.. Any ideals
Sounds to me like the vacuum pump, which the HVAC relies upon. When you turn the key to the "ON" position, you should hear the vacuum pump running for a few seconds, then shut off. The pump is located in the engine compartment. If it continues to run for an extended period of time (even with engine ON), or it doesn't run at all, then it's likely the culprit. If you purchased an extended warranty, have them check/replace it. If it's a problem you've inherited, there are youtube videos on how to fix or replace the vacuum pump.

Hope this helps!
 

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Discussion Starter · #3 ·
Ok I will check that. What does the pump control? Vent doors cause they seen to switch zones just not a lot of air output
 

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Yes, the vacuum is used to open or close the dampers as necessary.
 

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The Vacuum pump controls the damper door. But the default is to full Defrost. So if the vacuum pump or line is bad, You should be getting all your air blown up the defrost.

The Vacuum also controls the Auto Hubs. Turn your ESOF switch to 4x4 and see if your front wheels lock in. If you are spinning on the back and the fronts are not turning, then you have a bad pump or line.

A new pump is fairly inexpensive. I think the last one I swapped out was $100 and it's just 2-3 bolts. A 15 minute repair.
 

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Discussion Starter · #6 ·
No my 4wh drive works find .. My oontrols seen to work I can switch from defrost to vents to floor but there is not a lot of air flow. The blower switches from low to high but air is not making to the vents. Exactly where is the vacuum pump on the 6.7..
 

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All the previous Navstar Powerstrokes had an electric vacuum pump. Which is what I had to change on my 6.0. It appears the 6.7L has a gear driven pump on the front of the engine.

From the Ford Coffee Table Book

"The Vacuum pump is located on the upper portion of the front cover and is driven by the high pressure fuel pump. "

Doing a google, I found a youtube video of a mechanic removing to replace a leaking gasket . So unlike the previous versions, It's not a simple 2-3 bolt swap out.
 

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All the previous Navstar Powerstrokes had an electric vacuum pump. Which is what I had to change on my 6.0. It appears the 6.7L has a gear driven pump on the front of the engine.
I'm glad you pointed that out. With the known real-world reliability of of the 6.7L, I would have to assume that this is an improved design. I take it by your post that this is not as simple to fix when failure occurs? Maybe not as inexpensive, either.
 

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Information you've been given is incorrect the 2011 does not use vacuum to control the heater doors it is controlled with electronic stepper motors if you have no air coming out your vents is quite possible your evaporator core is filled with dirt or debris if that's what it is you're in for fun the local Ford dealer wanted $3,000 to remove the evaporator core and put a new one in by the time I was done with the job I wish I had paid it it requires removing the entire dash passenger side seat steering column
 

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Just purchased a used 2011 f250 6.7 ... My blower motor runs find the vent controls seems to work but little air is making it to the Windshield on defrost and same when switched to heat.. Any ideals

If you can hear that the blower fan is changing speed with changes to the setting and you have little air flow then you have a restricted A/C evaporator core. I see this on landscaper trucks on occasion where it is packed with organic material (dry grass and such) and dirt. The only way to remedy this is to replace the evaporator core. You could remove it and clean it however if you are going to take it out it is recommended that it be replaced.
 

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Discussion Starter · #12 ·
The truck was owned by selected energy services well drilling company or something out of Texas very dusty a lot if sand mud undercarriage I'm thinking clog a/c evaporator core...
 

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It seems obvious your truck has an air flow problem the law doesn't limit airflow to the point that hardly blows as you're describing. These trucks from the factory have substantial airflow from the vents the - dash vents floor and defroster vents blow hard enough to make the system work extremely well. If your blower motor is spinning and you can hear it change speeds the most likely cause is the evaporator is clogged. I own several of these trucks we run them for service trucks on the highways and off road in the desert of Arizona the dust in the desert is extremely fine and seems to settle into the evaporator box where there is moisture from the condensation which turns it into mud. The ones we have had to do have been completely plug on the bottom three fourths of the core the longer they operate the higher up the restriction gets due to the settlement of the dust. The first one I attempted to repair took approximately 14 hours the heater and air conditioning assembly literally goes from where your right foot is on the floor board all the way to the passenger side wall of the truck behind the glove box and from the floorboard to very nearly the top of the dash there are studs that go through the firewall one of which is not far from the turbo downpipe and is almost impossible to even touch much less take loosen a small air ratchet and reaching as far as you can is the easiest way to get it loose. It is necessary to drain the coolant from the system and evacuate the air conditioning refrigerant. You also have to remove the battery box the air intake and the windshield washer assembly to access the other bolts you must also remove the steering column and the entire dash assembly to access the unit itself in order to get it out of the cab you have to remove the passenger side seat unless you are very experienced and very patient I would much suggest that you take it to a dealer or at least someone who has worked extensively on these particular trucks from 2011 and newer
 

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Actually you DO NOT remove the steering column or the seat. If done properly you disconnect or remove surprisingly little from the dash itself. Leave both front seats in place and move them back as far as they go and the dash assembly gets placed face down across the seats. And yes, the nuts behind the turbo (if equipped) are indeed a PITA.
 

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Discussion Starter · #15 ·
You mention the battery box needs to be remove? 2011 both batteries are located by the headlights..
I just wonder how much a dealer would charge
Its looks like I will be doing this at home no other way to clean it?
 

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I have done 3 of these jobs. You may be able to avoid removing the seat but for the 4 bolts required it makes the job much easier but I see no possible way to avoid taking the steering column loose and again for the couple of bolts required it is much easier to with it removed especially if you work alone. With only one set of hands it is much easier to with removal of both.
 

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It is much easier to roll access the heater hoses, refrigerant lines and heater case bolts with the battery removed the box included a computer module and the windshield washer tank all one assembly. These trucks are difficult to work on as it is. A few more minutes to remove obstacles is the way to go. My local dealer quotes me 3000 for the job. That may be high but it is a tough job to tackle on your own.
 

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I am not going to get into a pissing contest with you. It is easier and quicker to perform the WSM procedure and leave the dash assembled (steering column attached) and just flip it onto the seats. If you have a reason for doing it by removing things that are not required to be removed then more power to ya but I don't think its sage advice. Maybe that is why it takes you 14 hours to do a 4.5 hour job? :thumbsup:
 
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Discussion Starter · #19 ·
Ok well I removed blower Motor and send my camera in the hole the evap coils clogged so I then cut hole on the glove box side between the heater coils and evap nice and clean shot air and water and then gunk the other side more water and shop vac with small hose replace blower works great down side crack blower fins will order new blower i hope aftermarket blower moter housing is smaller to make install easier
 

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