The Stovebolt Site Forums The Shop Area The Electrical Bay Rewiring instruments without removing the dash on an AD

Is it possible to install new harness behind the dash without removing it? I have lots of light, mirrors and short tools but can't even get my hands in there never mind my head. Is it possible? The manuals seem silent on this subject. (I did a <search> here but came up blank)

Andrew 1433,

It has to be possible because the dash is not removable. Would it be easier to remove both gauge clusters and wire them hanging out, then stick them back in? My '51 had a custom dash and I did it your way, with a pillow, mirrors and a 1/4" drive socket set.

Stuart

I would think removing the dash would be a real pain. The dash is welded not bolted in. The Gauges and speaker grill are out of my 52. It looks like there would be plenty of access through those openings. I am sure there is someone who has changed the harness and will have more wisdom than I have. If your gauges are still in it seems that starting with the glove box and working your way across makes it easier. It is not all that bad if you spray the nuts with liquid wrench. Hit the threads with a wire brush if they are real rusty first. The studs will break if you aren't careful. Make sure to take note of the wire locations. I removed the speedometer nuts through the speaker hole then worked across th the gauges. You can remove the gauge wires and oil tube once the cluster is loose working through the hole it was mounted in. The gauge cluster wires would be the hardest to get to and I would hate to try it from under the dash. I had the glove box, speaker and gauges out in an hour or so. The bolts on the gauges and speedo wil require a 1/4" drive socket, an extension and a swivel. Hope this helps. If all of that is already out and you still can't do it you could try training a 7 year old with little hands.

Good luck Neil

It can be done but you have to be a slender person, be able to contort in all kinds of positions, have tolerance for pain in your back and leg joints. Or find a man, woman, or child that is under 5 feet and direct them on what you want done. Cecil.............

Removing the seat helps.

They forgot to mention a sore neck!

My suggestion is to remove the speaker grill, then working across, remove the speedometer and then partially remove the instrument cluster. Also, you should remove the headlight switch and also the ignition switch.

I'm pretty slim but over 6' so the joints in my arm are too far apart. Perhaps I'll try to train a child. It sounds challenging no matter what but the pillow, remove the instruments and the 1/4" drive with swivel sound like good suggestions. I used my digital camera to get photos of what I couldn't see and that helps. Thanks for the suggestions.

They covered this in the June issue of Classic Trucks. The only point in technique that I thought was interesting was that they removed the steering wheel to provide room. That is quite prctical. Oh, and they have a photo under the hood that shows one of those new alternators made to look like an original generator.

Andrew, post back and let us know how it goes.

Neil

I second the recommendation to remove the steering wheel. also, remove the radio grille, radio, ash tray, and all the chrome stuff you can. I removed the gauge clusters as well, and it wasn't that difficult, except in a few spots.

Don't forget the Ben Gay.

Good luck.

Somewhere on one of these forums, I saw a picture where someone had lain a piece of plywood over the seat riser extended out to the firewall. You'll need to put a couple of supports for it towards the front equal in height to the seat riser.

It formed a nice flat surface from the back of the cab to the front on which to lay while working up under the dash. Having rewired my '49 a long time ago, I remember thinking it was a truly outstanding idea that would make the job a BUNCH easier.

I don't find the steering wheel to be a problem (in fact it's handy to grap hold of to pull yourself out of there).

Thanks for this. Sounds like a complete teardown and not worth the effort for a few runs of wire. All things considered I think I'll replace all the wiring while I'm in there. (aside - on my '49 Stude truck all the wiring is right in front of you on the firewall. Dead easy.)

I followed truckernix suggestion (right to left) and so far so good. Removing the speaker grill and radio blank gave adeqaute access to the ignition switch. I can feel the nuts which hold the speedo on so I'll remove it next, then on to the gauge cluster. So far the pillow, a selection of stubby screwdrivers and the 1/4 drive with flex head and extension have been my tools of choice.

Hello,

I know this is an old thread but I though it would be better to ask a question here rather than to start another thread.

I need to remove my gage cluster on my 55.1, and I am wondering how the oil pressure tube and temperature wire hook into the back of the instrument. Do they just unscrew from the back? Is it better to drop the instrument cluster first?

Thanks,

Joe

The oil pressure line can be unscrewed on the back of the gauge but the temperature gauge has a capillary tube that can't be disconnected. To remove temperature gauge you need to unhook it from the engine and then remove gauge and line as a unit.

Joe -

Another one of my long answers to a short question -

Disconnect the battery. Label all wires and bulbs as you remove them from the housings and gauges.

Remove the speedo first. It will make removing the gauge cluster housing MUCH easier. You may need to remove the ignition switch.

The oil pressure tube is held to the back of the gauge by a compression fitting. You can remove the tube before you remove the gauge or gauge cluster.

You cannot remove the tube from the temparature gauge. It will be easiest to remove the gauge cluster with the temp gauge attached. Be careful not to kink it when you pull it through the firewall.

While the speedo and cluster are out, lube the speedo.

Also while everything is out, you can spiff up the gauges, housings, and routing though the firewall ...

Reface the gauges if needed. New chrome bezels are worth the cost, too. If you are really anal, then paint the clusters in and out to match the original. The bulbs for the high beam indicator and the turn signal indicator are shielded by cardboard tubes. Be gentle with them. They will be old and dried out and will easily break off (if they are still attached to the inside of the cluster.) They should have red (hi beam) and green (turn signal) plastic covers on the ends. The plastic is often burned or broken off. You can try to find a suitable substitute. I painted my bulbs red and green instead.

When you run the speedo cable, and temp and oil pressure lines throught the firewall, note that they go through the grommets a little differently than earlier model trucks. '54/'55.1 trucks had the speedo cable, oil pressure tube, and temp tube in a 3-hole grommet in the firewall. The choke and throttle were in a two hole grommet. Don't know if anyone has found a source for the two hole grommet. A speedo grommet from most suppliers can probably be drilled to make a 3-hole grommet. The routing is noted in Sect 1, Sheet 3.19 in the FAM.

I believe that the speedo cable for a 55.1 should be a metal sheathed cable instead of vinyl.

A dual clip holds the speedo cable and wiring harness onto the firewall, as seen in Sect 12, Sheet 1.001 (left page) of the FAM. An alternative clip is shown on the facing page of the FAM (same Sect and Sheet number).

> Jeff Erickson's Lube and Reface Tech Tip
> John "53John3100" Rooney's Gauge Refurbish Tech Tip
> My gauge reface saga
> 70" metal case speedo cable - American Classic Truck Parts part #SPC-2
> Dual clip for mounting speedo cable and wiring harness onto firewall - American Classic Truck Parts part # FA-113
> Grommet thread with pics of the grommets.

Good luck,

- Lonnie

Thank guys. I know I would have screwed up the oil pressure capillary. My guess is its already kinked up but here's hoping. Lonnie, I will have your post next to me as I pull the gages. :-)

Joe