Tcheairs38655

Finished the front end rewiring of my 66 project car. There are a few firewall clips (3) which I'm not sure of their use. There are 2 (bendable) clips about midway down the firewall underneath the heater fan duct. Would these be for the ignition harness to the starter? There is also a clip in the bottom of the recessed well where the wiper motor/washer resides. Would this be routing for the ignition harness? I'm assuming that the speedo cable is clipped somewhere after it comes out of the tunnel, but I don't see a clip for it.

And finally, what is the correct routing for the battery cables (from the battery to the starter) and exactly where does the ignition harness drop down from where it is strapped to the hood release cable?

All of this is applicable to the 66 427/425 L72 engine.

Thanks very much

DansYellow66

The drawings in the AIM are probably your best source of information. From memory there's a clip below the heater case for the positive cable to the starter. The other one is probably for the speedo cable.

I can't remember the one under the windshield wiper recess off hand. The ignition harness drops down to the distributor/ballast pretty much from where they exit the main bundle wrapping.

Again the AIM is the best source, but if it's not clear posting a few pictures of the clips in question would probably get the best responses.

Tcheairs38655

Thanks Dan, I do have the AIM. I'll try again to decipher those drawings (more like sketches)...TC

DansYellow66

I can't remember who I made this sketch for once. Could have been for you TC. It can at least get you to some of the correct page numbers in the AIM for engine bay clips.



I don't remember that clip in the windshield wiper motor recess - maybe it's missing on my car. It would almost have to be to secure the wiper motor wiring. Nothing original about my car anymore but here is where my TI wiring came off down to the distributor.


From memory I think the pink and green wires in this clip run to the back up light switch.

NightshiftHD

Attaching a couple to help you. The first is from my L72 and I've marked on where the battery cable to starter clips and the speedo. Note in this picture my battery cable clip needs to be rotated so the closed part of the loop is pointing to about 10 or 11 o'clock (instead of 6 o'clock in this pic). Also this clip is pop riveted on, not a crushed aluminum rivet like all the rest.

The 2nd is a scan of UPC L72-D6 which shows how the battery cables and starter wiring drops down. Use this in conjunction with your UPC12-A9 page.

The top center clip above the wiper motor is for the harness to cross over to the right side of the engine bay. Hope this helps. Bill

Tcheairs38655

Thanks again guys...all very helpful. What pages in the AIM cover the L-72? I'm having trouble finding it in mine. Don't see anything on the index page.

TC

NightshiftHD

TC, there are several pages on L72 in the Options section at the back of the AIM. All the options are listed there alphabetically by option code. Also look at pages K66-A2 and K66-A3 as they show more wiring info related to our TI.

The way the AIM works is this ... the front section is how the "base" cars were assembled (ie: with no options). Then there are specific "options" pages in the back section of the AIM showing any differences from base cars which are listed by option code ... K66 is before L72 for example. Cheers, Bill

DansYellow66

TC - most of the page numbers in the AIM with clip location info are written down on that drawing I posted above.

NightshiftHD

Unfortunately Dan those page numbers do not necessarily relate to anyone's copy of the AIM unless they bought it from the same supplier. What would be more helpful that works for everyone's copy of the AIM regardless of supplier is to indicate the actual AIM reference numbers ... ie: UPC12-A9 or L72-D6. Bill

DansYellow66

OK - wasn't aware of that.

block66

Question on fan shroud and fan blades.. I have a 427/425 1966 coupe..how many blades on your fan...do you have overheating problems,,, thx

block66

Question I have a 427/425 66 coupe... how many blades on your fan...do you have overheating issues.. did you install an electric fan... radiator shroud configuration .. I have lota of space between motor and radiator..

NightshiftHD

My L72 in stock form (5-blade clutch fan, BB copper rad & shroud) will run quite hot everywhere except the open highway. I does not like stop and go city traffic (for long). After much experimenting, I find a 6-blade or 7-blade clutch fan with a properly flushed stock rad & shroud, and the gaps filled between the shroud make it very usable. I also added the stock BB A/C rubber flapper to the top of the rad support to help force even more air thru the rad. I have since added Vintage A/C so now have a condensor in front of the rad and even with the A/C on, it usually will not go over 210 on a hot day. I have not found any need for an electric fan. Those draw a lot of current and you may need to increase your alternator size if you go that route. Bill

block66

thank you.. I changed out to mallory electric ignition and this may be causing vacuum issues, not sure. I do have a 5 blade fan and changed out to an alum. radiator by Dewit.. At this point I am going to change to air condition car shroud to create more air flow to the block. ( I do not have air conditioning). This should help. To be continued....I do run very hot in traffic..

NightshiftHD

The main thing with ANY big block car in particular is to take the necessary steps needed to seal off all gaps between the rad and the shroud, and secondly any frontal gaps anywhere else allowing air flow over or around the rad. Air will flow in the path of least resistance, and this really becomes a problem in slow city traffic because you lose airflow through the rad. Proper shrouds with no gaps really help, but keep in mind all BB rad supports are not as effective as they could be simply do to the larger rad size which caused engineers to kick out the bottom a significant amount away from the fan. So your fan needs to be positioned as designed in the shroud to be as effective as it can.

Another suggestion you should consider if you have not done already is CONFIRM your temp gauge and sending unit are calibrated. By that I mean confirming when your gauge says its 210, that it actually is and not 20-30 degrees hotter or colder. Many sending units sold over the past 50 years do not send the correct signal to have your gauge read accurately. In my car I actually tested 5 or 6 sending units with my gauge before I found only 1 that allowed the gauge to read 210 when it was really at 210. I tested these all with a pot of boiling water and just changing the sending unit would throw the needle 30 or more degrees either way ... mostly higher.

So once you know your sending unit/gauge combo are reading correctly at the middle of the scale (you don't need any accuracy below 160 (the minimum operating temp), you could experiment with removing the t-stat which is really only there to allow for faster warmups (BBs warm up very fast as you know). The t-stat creates a restriction in the water flow back to the rad for cooling and by removing it, you open up the flow considerably. In fact with your properly calibrated temp gauge you may find it operates closer to 160 than 180 or more. Just make sure if you run without a t-stat that you allow the engine to warm for a couple minutes and avoid the heavy foot until it comes up to operating temp. Bill

block66

thank you..

Mike Greeley

i use a spark plug wire protectors to enclose the battery wiring on top of the solenoid. not original but it protects the wiring
nothing more exciting than a shorted positive battery cable..