71K5 - BP71K5's Just for fun build

[bp71k5]

So instead of just watching TV while I figure out my storage issues, I started to tackle the TBI ECM that has just been sitting on top of the AC box unsecured.

The glove box seemed like the best spot for it since under the dash is already clogged full of stuff. The stock AC unit is kind of unweildy and I'm thinking of replacing it with an aftermarket unit, but that may not be for a while.

Here's how the ECM ended up after being secured with a parts yard platic ECM holder and the stock cardboard glove box liner installed. I simply cut the back out of it to let the ECM stick through a bit. It does intrude into the space, but it's actually not that bad. I can still keep my registration, insurance, and other documents in there with no trouble.


And here's the junkyard bracket I modified (cut stuff off of) after being screwed down to a custom metal bracket.


And here's a shot of the metal bracket I plug welded onto the back of the glove box. It's just a bent piece of 16g steel with some screw holes. The blanket all around it is a welding blanket to keep the rest of the dash from catching fire.


Also was able to start grinding out the welds on the glove box door and used some filler to fix a couple dents that were hiding under the paint. the right edge is where the mods were done and I need to feather that edge out a bit since my weld joint was not completely flush. It should be almost unnoticable when done.

 

[vtblazer]

Good idea/nice work.

Where did you stuff all the other TBI electrics?

I put mine in the same spot but put 'all' of it back there.
Also modded the glove box liner by making it shorter.

 

[bp71k5]

Thanks, the only other thing in that area is the ESC module and it's just wire tied to the harness. I can get to it by sliding the ECM out.

The rest is in the engine compartment except for egr which I just removed.

 

[bp71k5]

Update: Glove box door completed

So while I was goofing around with the glove box, I thought I'd finally mount the ALDl connector and the main switch for the ARB compressor inside. The switch is use to to disable the compressor and both lockers from accidental engagement so it can be easily hidden and then activated when I need that capability.

Here's a couple of the final interior of the glove box.



The switch panel also doubles as a cover over a hole I can use to reach in behind the dash to access the radio and AC dict connections in the future.

And here's a shot of the epoxy primer drying after removing all the old paint and rust and a final bondo coat. It's upside down so you get an idea of the new shape.


And everything installed back on and "done" for now.

 

[bp71k5]

Once the glove box was done, I was pulling the truck out the garage to go on a joy ride and started to smell electrical burning and then saw smoke coming from under the dash near the headlight switch.

After a brief panic and shut down over everything, I disassembled the dash bezel and discovered that the wiring harness had been leaning on the edge of the metal portion of the headlight switch. The old headlight switch was toast, but the wire that had it's insulation rubbed through just had a minor abrasion on it and no signs over overheating so I taped it all back up.

The spot that shorted is below the green dot in this picture.


So I found a new light switch and got it back in. Then found a nice metal flange in that area that I was able to drill a hole to mount one of those wire clamps onto to keep the harness away from any metal. I also wrapped that area of the harness with extra tape to make sure.


While that was out, I might as well organize the wiring mess under there to prevent any more fires. Still not perfect, since I need to organize the left side a bit more. I was also able to replace the windshield washer pump while I was under there since that hadn't ever worked.


And technically I did this before the light switch, I welded up the trim holes in the passenger fender (came from a truck) and finished off my can of expoxy primer to finally keep the rust off of it.

 

[mnstrburbon]

Such a clean intall nice job.

 

[bp71k5]

Small wheeling carnage update

Small wheeling carnage update

For those that didn't see the pictures in the garage of my short trip to Hollister last week, here's a few pictures of what we did.

http://coloradok5.com/forums/showthread.php?t=262523

After hosing off the mud for several days, it's still not totally clean. I've got a weird starter noise (sounds like a gear grinding) that occurs after the motor starts, my throttle position sensor died, and my power steering pump is now constantly reminding me to replace it.

First one, the front diff cover received a pretty good gouge on the underside from that big rock. Nothing the 3/8" plate steel couldn't handle.


I also had issues with my front locker not working sometimes and then just turning on unexpectedly. After cleaning things off, I found that I had not fastened the relay down to anything and just tucked it behind the battery for testing and forgot about it. After the giant mud bog and water puddle fun, the relay was sitting in a puddle of muck inside the fender. My battery was really low and I could hear it clicking on and off and see it smoking while the truck was off. I haven't tested to see if it's dead, but I suspect it is. This was a practically new relay and "copper rust" has already started forming.


And if you saw the motor before, here it is cleaned up as best I can. The exhaust manifolds have this baked on layer of mud I can't get off without scraping. I may have to leave it there as a rust preventative coating.


I also didn't like stopping on a big hill for lunch without the parking brake. I had a clearance issue caused by the doubler pushing the transfer cases back and interfering with the cable. The transmission will hold the truck ok on a hill, but it feels kinda sketchy without the brake. I had hooked up a new parking brake "intermediate cable" that is 3" shorter than stock and it still wasn't holding very well. Here's an overall shot of how it's setup.


Here's where it rides up over the output shaft housing.


After adjusting it once again, it's finally working well enough to keep the truck from rolling out of my driveway, but just barely. I now just have to remember to unlock it before driving away. I keep forgetting and realize it after driving for several miles wondering why it feels so sluggish.

 

[doonjumper]

subscribed

 

[bp71k5]

Small Update: Heated O2 Sensor

Heated O2 Sensor

I've been making the k5 earn it's keep lately by hauling a ton of furniture up north to San Jose. I'd been keeping track of my mileage and was not happy with the 8mpg I was getting around town up until now.

When I last did a tuneup, I noticed the spark plugs appeared to indicate the motor was running a little rich even though my BLM numbers appeared to be ok after some talking to Brian at TBIchips. He recommended a heated O2 sensor to try and get more accurate readings and a possible mileage improvement.

Nothing fancy but since I was going the heated O2 route, I could move the sensor farther back in the system to catch exhaust gas from all 8 cylinders rather than the 4 I had before.

Nuff said, here's the pic of the new location.


I am now measuring a mileage improvement and am averaging about 11.8mpg without any change in driving habits. Most of that has been freeway driving so it's hard to compare the results with my mostly city driving earlier, but I could barely break 10.5-11.0 in the past if I drove perfectly. So with the winter gas formulation, it's looking like I may have achieved an optimistic 1 mpg improvement. I'll take anything I can get.

On another note, I did some auto swapping to consolidate our family vehicles from 4 down to 2 and now am the owner of a 1996 4Runner with a 277,000 miles on it! The 3.4L v6 has been overhauled by a dealer, but I haven't been able to find any docs on that. Runs pretty good, passed the smog test, and should be fairly reliable for my wife and kids. She might even follow me out to Moab and do some wheeling in September.

 

[StevoandaRedK5]

my grandmother has one almost exactly like that. been driving it for i know at least 10 years. still runs great. and they're fun vehicles to drive.

 

[onetonbb74]

sweet! digging the heated o2 sensor, I just may have to get one of those if it improves the mileage. Nice clean Toyota btw.

 

[BGKYK5]

On another note, I did some auto swapping to consolidate our family vehicles from 4 down to 2 and now am the owner of a 1996 4Runner with a 277,000 miles on it! The 3.4L v6 has been overhauled by a dealer, but I haven't been able to find any docs on that. Runs pretty good, passed the smog test, and should be fairly reliable for my wife and kids. She might even follow me out to Moab and do some wheeling in September.

So when are you going to start the SFA swap?

Did you just run the power to the O2 sensor to a hot-in-run source?

 

[bp71k5]

So when are you going to start the SFA swap?
Did you just run the power to the O2 sensor to a hot-in-run source?

This one will stay as-is. It just needs to stay reliable. I got the heated o2 from tbichips. It has a 3-prong weatherpack connector so I got a matching pigtail from the parts store and wired the heater into a "hot while running" spot on the fuse panel along with a new 10a fuse. I'm going to keep track of the mileage to see if it changes over time.

 

[bp71k5]

Update: Comfort improvements

Update: Comfort inprovements (noise, heat, and oil leaks)

I've been trying to make some minor improvements in comfort and the three biggest "comfort offenders" were the noise, the heat, and the leaks of both water and oil.

The noise was loud enough that I can't have a conversation with my wife without yelling and that makes for tough 1000 mile trips to Moab so I need to address that as much as possible. I removed the filthy dusty firewall insulation and cleaned up everything enough to lay down some sheets of butyl rubber mat to both cut down on resonance and keep a bit of the heat out. I don't like the look of it so I just applied it behind the firewall all the way to the top and down enough so I can either spray more liner up to it or run some floor mats.



Also did the underside of the trans runnel cover. I have tons of manual drivetrain noise from that spot.



I also used a marine urethane sealant on some of the sheet metal floor joints before a final coat of spray liner. Somehow dirt, oil and grime just seemed to collect in those crevices and it is tough to clean. It only comes in white.


I also replaced the leaky power steering pump, but that's not fun enough to post pictures of. But I did pick up an ARB tire inflation kit which turned out to be pretty useful. It comes with some quick disconnect fittings.



And this neat little end that will snap onto the tire valve with a little clip so I can just walk away while it's filling the tire and not have to hold it on the entire time. I've been using a football inflation adaptor end to blow out all the dirt and mud that seems to get inside the truck.

 

[GRINCH]

Great idea with the sealer. I will be spraying mine in a few weeks. Thanks for the idea.
Did you get a chance to test out the effects of the mat yet? Where did you get it?

 

[oldtoyboyd]

Where did you get the inflation tip from?

 

[bp71k5]

Great idea with the sealer. I will be spraying mine in a few weeks. Thanks for the idea.
Did you get a chance to test out the effects of the mat yet? Where did you get it?

The mat is called "hushmat" and is one of many that is supposed to cut down resonance from sheetmetal. It only needs to be applied to a portion of the panel, but I figured it couldn't hurt to try it as a thermal barrier as well. It also doesn't soak up water and dust like the stock jute padding up there and since the truck leaks water too, that's important.

I did add a piece above the exhaust pipe on the floor (under the truck) to see how much it did. With the truck just sitting and idling, the floor was surprising cooler than normal. I figured it would help, but not that much. :hmm:

So I did do some testing and discovered the primary source of heat from the floor is caused by the electric fans blowing hot radiator air through the engine compartment. So now I need to do some driving tests to see the real effects. I'll let you know.

 

[bp71k5]

Where did you get the inflation tip from?

It comes with the inflation kit from ARB. You can get it at any 4wp store.

 

[bp71k5]

Update: Noise and Insulation test, Mythbusters style

Finally got a test drive in and the noise reduction from the mat is pretty good. I can't hear the electric fans anymore when they come on and the noise is now primarily audible in the rear muffler area. I'm happy. What was not expected is that I get almost no heat insulation at all! In fact, I think the metal layer on top of it makes it feel even hotter than the areas without mat. Bummer!

After some research about the three different modes of heat transfer: convection, conduction, and radiation, I speculated that because a huge source of heat transfer in that area is from convection, that the rubber mat is not a very good insulator. The heat is transfered right from the metal floor through the rubber mat and onto it's aluminum skin. Conduction is also a factor, but since the exhaust pipe isn't touching the floor, convection is a much bigger factor so there's not much point in going after that.

But what about radiated heat? I've seen lots of infrared camera's and thermometers used to read engine heat, so maybe I can affect some of that? How effective might the reflective side of the mat on the other side of the floor be at reducing the interior temperature?

So I conducted a little test like you'd see on Mythbusters. It might be tough to see, but I added a section of vinyl mat to the underside of the floor right above the exhaust pipe.


I didn't cover the entire area under there for two reasons:

1. The stuff is expensive and I don't want to waste money adding it there if it doesn't do any good or the heat makes it fall off.

2. I wanted to test the temperature difference in different areas to see the effects.

Once that was on, I took it for a drive to get things all warm and toasty inside and found the area above the mat was noticably cooler to the touch than the other area. Cool! So I got out a thermometer to see what the real difference was. I measured in three difference places. One in the center of the area above the mat, the second in the area in front of that without any mat, and the third up next to the mat on the firewall. Ambient temperature was 86 degrees.

In this pic, I've labeled each test spot with the temp I measured after about 10 minutes in each spot to let the thermometer stabilize and make sure it wasn't changing.


I've got about a 13 degree lower measurement in the area above the mat. That confirms there's quite a bit of radiated heat that I can effectively reduce. I measured the same areas on the passenger side and there was no measurable temp difference in those areas, although it was cooler over there since there's no exhaust pipe running through.

So there you have it. I'm going to keep an eye on the mat and see how it holds up under there, but it appears like it will be ok. This also means that the heat from the firewall will need to be attacked from the engine compartment side. I've found some glass microspheres that are supposed to be a good paint additive that I might try in that area (similar to LizardSkin).

 

[Greg72]

Brian,

Before you get too obsessed with applying that stuff underneath, consider the following idea as well:

Most modern cars use a metal heat sheild as a barrier for exhaust heat. Since air is a lousy conductor of heat, even a thin layer of metal between the exhaust and the body creates two separated air zones that will cut down the heat transfer.

Adding a simple curved heat shield would be a simple test to perform, and of course you could do variations on the test where you add a "jet hot"-style coating to the shield, or apply that same metal foil matting (though I'd put it on the up-facing surface to there's no chance if it melting and falling down onto the hot exhaust pipe)

This subject is of great interest to me as well, my K5 had all the same heat soak / comfort issues even before I started my new build...and I know that if I don't do something similar I'll be cooking my sneakers just like the old days.