DynoDave
CO-ADMINISTRATOR
Motown Mopar-Wizard
Posts: 11,163
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Post by DynoDave on Jul 9, 2019 7:40:02 GMT -5
YUP, Dave. Just pulling at straws like we all are when noting makes sense. Keep in mind the OP said it happened on a long drive so over time it is feasible for a high resistant short (very low curent) to heat up a larger chunk of metal. Yeah, it's a weird one for sure. I think 71 thru 74 are all basically the same ignition switch set up. The lock cylinder is coupled to the actual switch right there in the upper column. All of the wiring exits the column just as it goes under the dash. Will be interesting to see what the final discovery is. Thanks for that...seen too many columns on old cars over the years, and couldn't recall how this one was set-up.
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Post by Charlie on Jul 9, 2019 11:22:58 GMT -5
Turns out, as someone mentioned there is no rag joint. Also, there is no u-joint (unless it's inside the column and I cant see it). All I see under the hood is one solid piece. So with that in mind, and since it's only 2 or 3 inches from the exhaust manifold, I could see how the heat transfer could take place. However, I still haven't determined that is the actual cause of this.
Last night, I spent quite some time out there in the driveway with the engine running and charging the A/C. Let's say I was out there for an hour with the engine running. I started to smell just a very light hint of something burning... but not like electrical burning. I grabbed the steering column just forward of the wheel, and everything was okay there. Then went further down and was looking around with a flashlight when I noticed one of the body plugs in the firewall just outboard of where the column goes thru looked kinda funny. Turns out it was starting to melt! I pulled back the top of the carpet a little bit and noticed there was no insulation under it, and the glue on the backside of the carpet was starting to stick to the firewall behind the gas pedal. Now... for the dumb part... guess what I did? Yes, I put my finger on the firewall! Know what happened? I got a good freakin burn! I don't know why melting glue and distorted body plugs didn't clue me in NOT to touch the firewall. But I did. I'm an idiot... I know.
So then I went for a drive to test the A/C on the road (which really isn't working that great but that's for another thread) and was out on the highway for a little over an hour. Never once did the steering column get hot. Everything was just fine. The other day, it only took an hour for me to notice the heated column. The only difference between last night and the other day is that last night was about 77 degrees outside and the other day was about 95 degrees.
After realizing how hot that area got at the firewall just for running the car in the driveway for an hour, it made me look around under the hood. Since the firewall electrical connection is right there, it's no surprise to me that these are often in poor condition. My wiring harnesses are new, but I think that I will get a closer look at where wires run behind the engine. Seems I recall seeing two or three wire that ran between the exhaust manifold and firewall.
When I got home last night, I did not think to check on the heat behind the gas/brake pedals to see if things had cooled down since more airflow while moving should have lowered temperatures. Although I do recall noticing that I could feel the warmth on my feet while having my foot on the gas, and figure that an insulating pad under there will certainly be beneficial to helping the A/C work easier.
I will just continue to monitor the column and report back any findings.
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Post by goldrush on Jul 9, 2019 12:49:42 GMT -5
I believe you are a lot closer to resolution than a couple days ago Charlie. Stagnate air instead of moving air can make a big difference. Even at upper 80s ambient temps that engine bay has got to really be heating up.
Sounds to me like a layer of DynaMat/DynaLiner/DynaPad or a combination of them would make your feet a whole lot happier.
I'm trying to wrap my head around why things are so hot there. Are you running advance timing or a lean air/fuel mixture? What is your engine temp gauge reading?
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Post by 71se3834v on Jul 9, 2019 20:36:32 GMT -5
Exhaust manifold leak?
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DynoDave
CO-ADMINISTRATOR
Motown Mopar-Wizard
Posts: 11,163
|
Post by DynoDave on Jul 10, 2019 21:56:25 GMT -5
Turns out, as someone mentioned there is no rag joint. Also, there is no u-joint (unless it's inside the column and I cant see it). All I see under the hood is one solid piece. So with that in mind, and since it's only 2 or 3 inches from the exhaust manifold, I could see how the heat transfer could take place. However, I still haven't determined that is the actual cause of this. No rag joint, check. It doesn't have a joint like this one? EBAY LINKLast night, I spent quite some time out there in the driveway with the engine running and charging the A/C. Let's say I was out there for an hour with the engine running. I started to smell just a very light hint of something burning... but not like electrical burning. I grabbed the steering column just forward of the wheel, and everything was okay there. Then went further down and was looking around with a flashlight when I noticed one of the body plugs in the firewall just outboard of where the column goes thru looked kinda funny. Turns out it was starting to melt! I pulled back the top of the carpet a little bit and noticed there was no insulation under it, and the glue on the backside of the carpet was starting to stick to the firewall behind the gas pedal. Now... for the dumb part... guess what I did? Yes, I put my finger on the firewall! Know what happened? I got a good freakin burn! I don't know why melting glue and distorted body plugs didn't clue me in NOT to touch the firewall. But I did. I'm an idiot... I know. Oh, I would totally do that. So then I went for a drive to test the A/C on the road (which really isn't working that great but that's for another thread) and was out on the highway for a little over an hour. Never once did the steering column get hot. Everything was just fine. The other day, it only took an hour for me to notice the heated column. The only difference between last night and the other day is that last night was about 77 degrees outside and the other day was about 95 degrees. You are going to HATE me for this, and I am NOT trying to be a smart . But is it possible that the day that it got real hot, it was baking in the sunlight? Either way, something not right about body plugs melting. And carpet insulation is a huge YES. Even good A/C will struggle if your engine if throwing that much heat at the interior.
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Post by 71se3834v on Jul 11, 2019 7:44:49 GMT -5
Yes that is the joint that is used. Kind of a slip joint with 2 pucks that attach to the column that can move up and down in the cup, filled with grease, which is attached to the steering gear. Interesting that they went to a rag joint in '73? in the cars but I remember rebuilding that joint on my '79 W150 4x4.
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Post by Charlie on Jul 11, 2019 9:17:08 GMT -5
Okay- was gone a couple of days. Had to make a trip to Mississippi. Holy crap- the rain I passed thru in the Baton Rouge area yesterday was intense!! Made that trip in my 77 F150. Was a nice drive once I got out of all that rain!
Yes, I do have the coupler shown in that ebay listing. I never really thought of it as being a rag joint... but I guess it could be a type of rag joint. Didn't realize there was grease in there. Makes me wonder if it's still got grease in it after 48 years. As far as placement goes, the steering shaft is still close to the manifold even once you're past the coupler.
Now if you look at where the shaft enters the column, there is a round nylon piece (I guess it's nylon) that looks like it clips into place. It goes around the shaft and attaches to the bottom of the column. There's a gap between the nylon piece and shaft... which makes me wonder if hot air can make it's way up the column. I will try to come up with an idea to experiment with that thought for later.
Temperature gauge on the highway with AC running and 95 degrees outside damn near makes it to the center of the range... but not quite. I've felt very comfortable with where it reads.
Yes, I will soon be investing in insulating material of some sort to go under the carpet. That would help on SOOO many levels!
Dave, I kinda thought about the baking sunlight idea a few days ago as well. On that particular day, the car had been outside all day long. I sure did wonder if it could have been something as simple as that! All this worry over something as crazy as direct sunlight! I will have the car out an about later today and will look at how the light comes in. We're about to be dealing with a generous amount of rain soon, so hopefully I will get to drive and observe what happens under those conditions. I guess I could also just back the car out of the garage and let it sit for a while... come out later and start feeling around.
The first time I noticed it (back in January) wasn't hot outside by any stretch of the imagination, but it was a nice, pretty sunny day.
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Post by brigond on Jul 14, 2019 18:58:01 GMT -5
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Post by Charlie on Jul 15, 2019 22:04:48 GMT -5
Unfortunately, I've been called back to sea a little earlier than expected and had to drop everything to prepare to leave. I'll be back around the first of October and will continue this at that time. Thanks to those that have provided ideas and insight.
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Post by 71se3834v on Jul 15, 2019 22:10:34 GMT -5
That's a long time to ponder it!
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