Our signature vehicle is the Ford Edge with an inoperative A/C and a pervasive burning smell under the hood.
This week, I visited two country shops where I’ve placed grads, and both shops are well-equipped and busy. Elite Automotive is one of those busy country shops where you’re just as likely to have a Bobcat front-end loader in the service bay having the tracks replaced as you are to see a Chevy pickup in for a clutch job or a 2009 VW in for an engine swap. Among the many vehicles waiting for service on the lot was an ancient fire truck that rolled off the line before WWII. One guy had just replaced the engine in a 2009 Jetta with a salvage yard unit (customer’s choice) and it ran just fine after the swap until it started knocking, so all that work would need to be done again.
The other country shop I visited was Bay Springs Auto, another busy country shop owned by Donnie, a friend of mine who has been in business at this same location for seven years, and that’s where I spent yesterday working with and observing Matt, another one of my grads who has been employed there for a couple of weeks. Donnie was just finishing up a vintage 1968 Mustang in which he had upgraded the powerplant from the original hot water six banger to a crisply rebuilt 289, complete with throttle body fuel injection and plenty of chrome.
This is the Snap-On borescope look up through the blower motor hole into the evaporator case – in addition to these leaves, there was a lot of dust clog.
The owner had purchased that 289 engine after having heard it run and had taken it home, planning to bring both the car and the engine when it could be worked into the flow. He called Donnie and asked if it would be OK to replace the oil pan and valve cover gaskets and maybe clean the engine up a bit, and Donnie told him it would be fine. Two months later, with the beautiful freshly painted gold Mustang and the vintage replacement V8 engine finally at the shop, it turned out that the engine was locked up.
Upon interrogating the customer, Donnie discovered that while guy had the engine oil pan and valve covers off, he decided to wash everything he could see with dishwashing detergent and a water hose. The end result was predictable – the engine that was running right before he bought it was now scrap iron in need of reconditioning. Well, in truth that wash job wasn’t such a bad thing, because he did get a fresh rebuild, even if it was a pricey one, and this cream puff of a Mustang deserved it. The guy even got a sequential turn signal kit installed. This was a beautiful machine when all the work was done.
This 2001 4.0L Explorer engine requires a lot of torque-to yield work on the jackshaft and camshaft bolts and a bevy of special tools to keep everything locked in and in line.
Air Flow Issues on an Old C1500
In Bay Springs’ service bay No. 1 sat a faded blue 1988 Chevy pickup with a brand new A/C compressor installed but with lousy airflow into the cab, and another tech, Ben, removed the blower for a rat’s eye look at the evaporator core, which is hard to see without a mirror or a borescope. With Donnie’s Snap-on scope fired up and the probe peeking up through the blower hole into the evaporator case, it was evident that leaves and dust had been making their way into the fresh air vents for decades. There was probably a pound of dust and a cigar box worth of leaves nestled up to that heat exchanger, and it needed hosing.
The good news was that the old truck had rubber mat in the floor instead of carpet, so it was parked out onto the sloping drive where some some creative water work was applied to clear the core and case of dust and leaves, with some of the water going out the evap drain and some running out of the truck’s floorboard and off the edge of the concrete. Farmer Brown couldn’t care less if we got his rubber mat wet, he just wanted to cool down on these humid, 90 degree South Alabama days, even if it has been cooler in Alabama this summer than any in recent memory.
This truck had intermittent oil pressure gauge problems (lifter clatter was never heard even when the gauge was down), and the owner opted to hire the shop to pop a 2-inch lighted gauge under the dash. Donnie opted for an electric one so as not to pipe oil into the cab. The problem with this ’88 Chevy V8 oil sender is that it is mounted near the rear exhaust runner and tends to fail because of the heat, and that may well have been the root of the intermittent gauge anomaly. Donnie opted to fashion a heat shield with a piece of tin, which didn’t hurt a doggone thing.
I don’t have a photo of the tool that locates the crankshaft at No. 1 TDC, but the tool on the left locates the camshafts and the tool on the right holds the gear securely during the torque-to-yield process. The bolt on the right rear gear is left hand thread, by the way.
The 2001 Explorer
As the Mustang job was drawing to a close, the guys jerked the engine out of a 2001 Explorer that had the noisy timing chain syndrome for a partial rebuild. The guy wanted all the chains and nylons plus a total engine reseal, a new high volume oil pump and a fresh torque converter and seal because they were exposed with the engine out anyway.
Matt set up the tools the way I had trained him so as to put the camshafts and crankshaft in time. For those who aren’t familiar with this platform, it has three timing chains, one of which drives a jackshaft that spins in the bores where the old in-block camshaft rides on OHV engines, and this jackshaft drives the two overhead cams via one chain on the left front and another on the right rear. There are no timing marks on anything and you need the special tools to set the chains up. One tool locates the crank at #1 TDC and there is a tool that puts each camshaft at the proper index before the cam gears are torqued, with the camshaft gear holder bolted to the head and pegged securely into the gear that is being torqued.
That being said, if you understand how things line up you might get these shafts pretty close, but the cam gear retainer bolts are all torque to yield and have to go another 90 degrees after initial torque, thus the need for special tools to lock things in place during that torque procedure. More engines than ever are being built this way now, and special tools abound. The timing chain job went on the back burner for lack of a couple of crucial parts that were en route, but the parts did arrive for the ’07 Edge A/C job.
Working on the Edge
The A/C wasn’t cooling on this 2007 Edge, and while there were no blown fuses, the heavy scorch smell in the engine compartment pointed us to a partially shorted clutch coil that had lost its ability to magnetize but was producing enough heat to begin liquefying the rubber parts of the clutch pulley. A new compressor from Ford runs nearly $900, but you can get a new aftermarket unit for just under $500, and that option was pursued on this job.
On the Edge, after recovering the refrigerant, the fascia had to be removed, the coolant was drained, then the fan and radiator/condenser package was removed so as to access the receiver/dryer sock. This is a TXV system, but there was no reason to change it for an external compressor failure.
Some A/C compressors can be replaced in literally 15 minutes, but this wasn’t one of them. Further, we all know it’s a dereliction of duty to replace a compressor without also replacing the receiver/dryer, which in this case was one of those long white desiccant socks that goes in that skinny can built onto the side of the condenser. Because the compressor failure was external and there were no metal particles circulating with the refrigerant, the decision was made to leave the expansion valve alone.
I yanked the plug and changed those desiccant socks quite easily on some other vehicles, but this Edge required quite a bit of work. The condenser has to be removed from the vehicle in order to access the plug on the bottom of the can that houses that desiccant cartridge, that being a moderately major operation that started with coolant recovery. Donnie’s Robinair J2788 compliant machine does a smashing job of that, and it also extracted three of the four ounces of refrigerant oil that were in the system.
Matt delved into ALLDATA, waded past some confusing pictures of bolts that didn’t exist on this vehicle and figured out how to remove the fascia in short order.
Flipping the radiator and condenser upside down, it took a 14mm Allen to get this plastic filter plug out and some mechanical fingers to grab the sock. The new plug looked right but wouldn’t fit, so Donnie used the new o-ring and the old plug. This kind of misfit happens a lot more than it should.
Next, he drained that apple-juice-looking gold coolant, removed the air cleaner and unclamped the top radiator hose, bending it around and away from the work area. Then set about to removing the fan, first disconnecting the shroud-mounted fan controller, then unclipping wire harnesses and whatnot that were attached to the shroud. Within a few minutes the fan module was out and on the floor. There were two more hoses connected to the radiator, one of them the lower radiator hose and the other one the one inch coolant feed hose from the fill tank, which, on this platform, is mounted higher than the engine for easy bleeding. Donnie demonstrated his cabled spring hose clamp squeezer, much to Matt’s amazement (I don’t have one of those in my department, but I should).
He and Donnie unclipped the radiator, disconnected the two plastic condenser line anchors from the passenger side radiator tank and tilted the radiator back so as to unbolt the peanut fittings from the condenser where each line was connected, and then they worked it out of there, bringing the condenser with it.
To remove the compressor, the bottom stud had to be screwed out of the mounting boss and removed with the compressor, which, in this case, showed signs of electrical coil failure. It didn’t blow the fuse, but it got plenty hot enough to do this, and all the customer had was a blower moving hot air.
It was time to replace the desiccant bag by screwing the plug out of the bottom of the condenser with a 14mm Allen bit, then he went to work fishing the old sock out of there with mechanical fingers. Sliding the new desiccant bag back in was easy, but the new plug that came with it actually looked right but wouldn’t fit. The flange on the bottom of it was too big install in the radiator. So Donnie filched the O-ring off the new one, installed it on the old one and had Matt screw the plug back in.
At this point, it made sense to replace the compressor while the radiator and fan were out of the way, and that job went like a song the lower of the three fasteners is. However, a nut and the stud that the nut mates to have to come out before the compressor can be removed. The hex on the end of that compressor retaining stud is a 5 millimeter, and Donnie worked it out of there with his battery cable pliers.
The annoying thing about new compressors is that some of them come with paperwork in the box telling you how much oil is in the compressor and some don’t. We took the plugs out of this one and turned the hub clockwise until we saw oil, then stood the compressor on its nose to lube the shaft seal, and had the burritos and sweet tea Donnie’s wife had brought us for lunch before stuffing everything back together, filling it with new Motorcraft Gold coolant, adding 3 ounces of fresh oil and 1.21 pounds of R134a. Reinstalling the fascia and the right front tire, a cool test ride down the road showed 46 degrees at the register with ambients in the low 90s.
With the fascia reinstalled, the Edge was customer ready two hours before quitting time. It was a good day.
With everything reassembled (new o-rings) a 50/50 coolant mix poured in (no special bleeding necessary because the fill is higher than the engine on this one), a vacuum on the HVAC and the addition of 3 ounces of oil (the compressor had an ounce and a half in it and the total charge is 4 ounces of oil), and after checking for leaks, the fascia was reinstalled, the test drive was cool and comfortable, and service bay number four was ready to take another job.
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