Ford A/C :: 1977 F150 - Compressor Really Vibrates At Low RPMs
Aug 11, 2006
I bought a 1977 Ford truck a couple of years ago. It has factory air, but the compressor was removed and the hoses were capped and/or poorly taped off when I bought the truck.
I got the bright idea, I'd try to get the air going, but I didn't know anything about a/c systems. I bought a York type (same as what it would have had originally) compressor from Autozone. They told me it was for r134. I put it on the truck along with a new filter/dryer and new expansion valve.
I took the truck to the local shade tree mechanic and he stuck a el cheapo vacuum pump on it for a little while and threw some oil and two or three cans of r134 in it. Well... since then, two summers have passed and it has never worked right.
The compressor really vibrates at low rpms. The air is just barely cool enough to tease me into thinking I have air conditioning. I know this sounds odd, but it seems to work best after I've sat at a stop sign and then take off. It's like idling the engine allows it to "catch up to itself" and then when I drive about 30 mph after a stop sign it actually blows pretty cool for a couple of minutes. But at highway speeds it isn't cool at all. This seems to be the opposite of what I've read. I had the heater & a/c box all apart changing the heater core and all the doors and seals are in good shape inside it. I don't think I'm getting outside air in. At least not in any quantity.
Last summer a friend tried to had one of those cheap gauges and he tried to put some r134 in it but it didn't accept much at all; and it didn't work. I've had about as much as I can take. I need some air conditioning. Should I try to flush out the system, install a new filter/dryer, and get a fresh charge of r12? I'm concerned about trying that because the kid at Autozone told me the compressor was for r134.
I'm pretty confident I don't have any leaks in the system.
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I got in my 1977 f150 V8 windsor the other day and headed down the road. All of a sudden I started to hear this sound that only way I can describe it is a big log chain moving around or a box of washers being moved around. I got out, popped the hood and thought at first that it was a pulley somewhere on the front of the engine, perhaps water pump pulley or something like that. The closer I got my ear to engine though I think it is coming from the back passenger side of the engine, not the front. I could be wrong about that, but I do know it is coming from the passenger side of the engine. Sometimes it will go away for 1/4 of a mile and then come back. I also noticed that it gets faster when I give it gas and slower when I don't, which is why I was thinking it had to be one of the pulleys going bad. I'm not so sure though because I think it may be coming from the passenger back part of the engine.
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I have been fixing up my 77 F150 since I got it in January and it's really starting to look nice! I love this truck, but I have noticed a clunk sound when I put it in reverse and also a same if not similar sound when I'm driving and slow down. It makes a clunk sound when it shifts to a lower gear, (automatic). Now, I was thinking it was a U joint at some point and crawled under there and started to grab them and see if there was any play in any of the spots but found no play. I checked it a few times, thinking well it could be just the point the U joint stopped and that would explain no play but after a few times of crawling under I still never found any.
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Ok, I have a 95 F150 5.0. It's sat for 6 months with the engine taken apart. I just finished putting everything back together with a new alternator. Well, I pulled a bone-head move and forgot to connect the harness when I fired the truck up. Other than not charging though, it ran fine. When I connected the harness, it began to chirp and shudder at low RPMs and squeal and vibrate at higher RPMs and it over heated VERY QUICKLY.
So hot the case was too hot to touch and the pulley smoked the belt. The engine didn't even have time to get up to operating temperature. I've had the alternator replaced twice, and this last one tested good putting out 14.5 volts. The work I did on the engine was to replace the valve springs, install a direct drive timing gear, replace a spun harmonic balancer, bypass the smog pump because it froze up, new distributor, a new ECU and O2 sensor.
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I've got a 1991 Ford F150 Super Cab, 351 Windsor 5.8L V8, 2WD with 177000 miles on it. It rocks, I love this truck. But above 60 miles an hour I start to get a horrible vibration throughout the cab, mostly under the seat. It gets worse the faster I go to the point the whole cab vibrates. The challenge is that it only occurs when I'm on flat interstate, with just enough gas to maintain speed. If I accelerate, it goes away (or subsides quite a bit). If I let off the gas, it goes away completely. I had a transmission diagnosis from a local, reputable shop, and they said the tranny was fine. They said it was something in the engine, but I'm baffled that something in the engine could cause such a vibration all over the cab. Any thoughts on what this might be?
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I have a 2007 Ford F-150 small box bought new, now has 80,000 miles. The rear end started to make a slight roaring noise that started to turn into a vibration. That turned into a major vibration (windshield wipers would hop). I figured a bad U-joint, but it had no "clunking sounds". I took it to a non-dealer mechanic and he said the "rear end is shot, and also a bad leaf spring..." I do not tow with this truck, or go off road, but it does have a Tommy lift installed. Does this sound normal for the miles and usage of the truck? Any recalls for this model that effects the rear end?
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I have a 2000 F-150 4.3l and a/c compressor will not come on. I checked the pressure on both high and low side, low side is sitting at 90# and high side at 100#, with nothing engaging on clutch. I turn the fan to max a/c and fan to high and light comes on on dash for a/c, but I can't hear anything engaging on compressor and clutch looks like it is standing still while belt is rotating on engine. Had to check here to get fuse schematic and check fuses, but beyond that not sure what to do next.
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1992 f150 4.9L, bought it a couple of months ago knowing the ac wasn't working PO had it converted to 134, said it worked great until they put on the bodylift. Compressor clutch is working, I'm sure I have some blend door issues but I've bypassed the heater for now.
AC on max, outside temp 85*, engine off high/low at 100psi, engine at idle low 55psi high 125psi, center vent reads 93*. When engine at apox. 1800-2000 rpm, low 35, high 180, center vent reads 85*.
My guess is the compressor is worn out. Is there another way to test? If I do replace what else do I need to replace? I'm hoping there's something else I can do/check before replacing the compressor.
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2007 Ford F150 half-ton. No cooling of air at the outlet of the ductwork. Freon charge is good, I watched the tech pull the system down and hold it for the prescribed time period. Compressor will not start. I am being told that this means a failed compressor, but I am of the idea that the pressure switch for low pressure must have failed, or the orifice is stopped up. I am also being told that the compressor, evaporator, and orifice tube needs replaced in order to remedy this issue. The counter man at my local parts house cannot find in his computer any pressure switches, kinda making me think that everything is in the unit. In short, if I can avoid buying the compressor, I would like to.
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The Truck: 94 F-150 XLT 5-speed 300-I6
The Problem: AC blowing hot air.
What I've done: Start the truck, look at the compressor, (looks like it's spinning to me), engage the AC, look again (yep the pully on the compressor is still spinning).
And that's pretty much where i stopped, cause i don't know what i'm looking for, should i be seeing it not spin if it where seized, and whats next on the list to check.
I assume that it's not seized at this point and it must be something else, like a control, keeping it from working.
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Have and intermittent condition with my 1996 F-150 4.9. AC runs and then cuts out (compressor not turning). I lose 12v to both side of high side switch. I tried to troubleshoot using a schematic in Haynes Foprd Pickups and Bronco for 92 and later F-Series/Bronco, but the color code for the wiring doesn't match up.
On my truck, there is 2 wires from the low side pressure switch which mates to a socket with only 1 wire. I have 12 volts at switch terminal on dash control, and it seems that I have an broken wire behind the dash, as I can get it to operate again when I move the harness around. Where can I get a schematic of this part of the circuit?
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I got an old 1989 F-150, manual, in-line 6 engine, with an 8-foot bed. I use it for hauling landscaping equipment, as i am starting a business. i will likely start hauling trailers with it this summer, but I also just want the engine to give me more power.
What are some things I could do to up the HP, or a better truck in general. I'm not looking to make it into a 350Hp monster, just get a little more out of it. What can I replace or add that would do this?
First, the idle dies on me when i put it in neutral, or gets stuck at 2500rpms. is this a vacuum leak, or the idle-air control valve?
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I just bought a 1991 F150 with a 302 (5.0). It idles at around 2600-2800 RPMs. The previous owners replaced the TPS and IAC, but it still idles fast. Ford dealership told them it was a vacuum leak. Are all the vacuum lines close to each other? How easy is it to locate/fix the problem?
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I got a 99 jeep sport straight 6. AC works fine after topping off. Pressure 32 l/s 210 h/s could still be a little low but air is very cold. Problem is while drive compressor shuts off. I thought it may have been too low causing it to kick off. while in park & holding rpm's at 2k everything seem to be ok.
It cycled on/off at times as normal but then compressor stopped & didn't come on again. shut the engine off checked the fuses restarted & the air is back running like normal?? so whats going on do I have a bad l/pressure switch or may be a relay sticking??while at 2k rpm's l/side 25 h/side 250 then at idle 32 & 210. I don't think its low enough to cause the shut off but.....
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I just changed my 77 truck over to a Serpentine belt set up and used parts from a 90 F150. I didn't flush the system, but I did replace the drier and added oil the way that was suggested in another thread (by measuring what came out of the York). I pulled a vacuum for 40 minutes then let it sit for 30 minutes and it held just fine, so I went ahead and started charging the system. My pressures seem to be right with the low side about 50 and high side 175 with it about 85^ outside.
The air isn't blowing very cold, it's more cool, and the low side fitting doesn't feel cool to the touch the way it did when I had the York compressor on there. So I'm confused and wondering if the compressor I took off the 90 is bad. One thing I noticed is when I shut the truck off was that the pressures equalized almost instantly, when the York was on there it took it a while for the pressures to equalize. Is this a clue that the compressor is bad or is that how newer one's work?
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I have a 77 F100 2wd 302/c4. I recently replaced the rear plate to my gauge cluster after it crumbled to pieces. I swapped all the gauges to the new plate minus the fuel gauge since it decided it couldn't live if livin was without the old plate. I have a gauge cluster out of my 75 and decided to swap in my fuel gauge from that one. I put the cluster in the truck and fire it up for 10 mins or so and everything is working great except the temp gauge isn't moving. I figure it romeo and Juliet with the fuel gauge so I just swap all gauges from the 75 into the 77 cluster except the speedo. Same result.
So I figure its the sending unit now and maybe both gauges were fine to begin with. I put in a new sending unit and now the gauges works but the needle sits on the P in the word TEMP on the gauge which makes me uncomfortable. That's about 1/4 inch or so from being past the end of the gauge. I don't believe the truck is running that hot. The gauge was more or less straight vertical before the swap sitting right at the end of the E on TEMP. Did I get a bad sending unit? Is it a bad ground on the gauge? Was I supposed to take off the teflon tape that came on the threads of the sending unit? I'm gonna try removing that first and see if it lowers the needle.
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The battery light in my well used 1997 Ranger came on a few weeks ago. Only use the truck on the weekends. Battery reads 12v. Alternator putting out 14v. Replaced terminal clamps as they were in bad shape. Light is still on.
Weak battery possibly? Does it need to read higher than 12v for the light to be off, I wonder?
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I have a 77 F250 with a NP 205, when I lock it into 4H the 4wd works, when I lock it into 4L it goes into low range but the 4wd does not work. What the problem could be?
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I just had a former Ford tech rebuild my motorcraft 2150 2v on my '77 F250. I took it home, put it back on the truck and it ran kind of rough. I then went ahead and screwed both idle mix screws in untill seated, then back out two turns. The truck ran great, turned off truck then when it the house for dinner. Half an hour later I come back out...truck will not start, just sits and cranks. Finally got it started and it ran good, but crapped out after it warmed up. I have made sure there were no vac leaks when truck was running the first time. Did I adjust the mixture right?
The truck is a '77 F250 400/C6
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Have a 1977 ford f150 with 351m with a motorcraft 2150. Had ( who I believe was a reliable source ) rebuild carburetor for me and after putting back on I can only keep engine running with foot on pedal. I turn idle mixture screws all way in and then proceeded to back out equally. This does not appear to be doing anything. I did turn the choke 2 notches to lean and was able to get it to idle but it wasloping so bad i shut it down and put the choke back to the middle setting.
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I noticed last night while messing with my truck that I have a constant small spark on my throttle linkage on my carb. BTW, it's a 77F250 with a quick fuel Ethanol carb with an electronic choke. That really probably don't make a difference anyway. Is this a common thing and do I need to run a grounding wire from the carb to the rest of the engine?
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