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Do 1972 350 A Bodies with AT use these Tabs to Retain the Wiring Harness?

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Do 1972 350 A Bodies with AT use these Tabs to Retain the Wiring Harness?

Old February 2nd, 2019, 12:05 PM
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Do 1972 350 A Bodies with AT use these Tabs to Retain the Wiring Harness?

https://www.ebay.com/itm/352206670563?ul_noapp=true





Inline tube says they are only used on 4 speed cars, not with automatic transmissions. OPGI say nothing about it... My 1972 AT Vista Cruiser didn't have them, but was missing quite a few parts that have to do with the wiring harness. I also have a bunch of fried wires that run very close to the exhaust header where they go to the starter solenoid and I can't imagine that the following tube is all that's needed to fix that problem?...

https://www.ebay.com/itm/1968-72-CUTLASS-442-W-30-W-31-350-455-POSITIVE-BATTERY-CABLE-TUBE-AUTO-TRANS/161938373886?hash=item25b4477cfe:g:VbUAAOSwBt5ZLvR a:rk:4f:1&frcectupt=true




Finally, here are some clips that go somewhere on the spark plug wires although I don't know exactly how or where. Hopefully the assembly manuals that I just bought will finally help me sort through some of these questions, but you guys might be able to help me decide which parts I'll need.

Thanks, Tom


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Old February 2nd, 2019, 01:35 PM
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I don't know the answers but Brandon on this site has a much nicer and authentic battery tube reproduction than the plastic part pictured
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Old February 2nd, 2019, 01:43 PM
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Link to Brandon's Battery tube ad
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Old February 2nd, 2019, 02:32 PM
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Originally Posted by RetroRanger View Post
Link to Brandon's Battery tube ad
Thanks! Wow! That is really nice, but since I need the bracket too and for the price difference I think I might stick with the one from Inline tube for my daily driver car (eventually, once it drives :-)...
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Old February 2nd, 2019, 02:46 PM
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The inline tube one is cheap plastic instead of garolite. If you factor in shipping you'll be close to the price Brandon is asking for his - shipped. You could always PM him and ask if he'll sell for less.
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Old February 2nd, 2019, 06:09 PM
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FYI 350 w AT would have the bracket and tube on the frame not the engine. I sometimes see good used tubes for sale. And you could probably could find a used bracket as well. You can tell I don't really care for that plastic part!

as far as those tabs I took a piece of sheet metal and cut and drilled it once painted it looked no different.
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Old February 2nd, 2019, 08:44 PM
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You said "exhaust header"....are you running headers OR are you running stock exhaust MANIFOLDS?
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Old February 2nd, 2019, 11:54 PM
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Originally Posted by 70Post View Post
You said "exhaust header"....are you running headers OR are you running stock exhaust MANIFOLDS?
Wrong word. I meant manifolds and my starter wiring runs maybe 1/2" away from the back side of the rear part of the hot manifold whereas from the pictures I've seen that garolite tube seems more like a holding bracket than a heat shield. Is there another heat shield for the harness where it's close to the manifold?

It looks like the metal tabs and straps on the left valve cover really were only used on the 4 speed transmissions because the battery cable ran somewhere else on the AT....
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Old February 3rd, 2019, 12:09 AM
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Well....if you're running stock manifold and whatever size headpipes then the ILT setup you show is a repro of the factory setup (other than the plastic vs. Garolite tube). It worked PERFECT. The REAL garolite is probably some sort of heat resistant material.....yes, it's a "holding" bracket BUT the material is very durable when it comes to whatever heat is present down there. I have numerous originals of this setup and many are in super condition so the heat didn't cause the tube to deteriorate, etc.

If it really bugs you then you could get the 4 speed battery cable tube setup - it uses a different metal bracket AND tube VS the auto setup (and the 4 spd POSITIVE CABLE)...this will place/run the cable down the inside of the D side valve cover and then it'll make a "downturn" at the back of the motor and feed the cable/harness down the BACK of the cyl. head/block instead of crossing OVER the exhaust pipe, etc.

On the valve cover tab I think you're correct...at least for the D side valve cover....only used on 4 spd cars to hold the battery cable.
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Old February 3rd, 2019, 12:18 AM
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Also - overlooked one of your questions..."is there another heat shield for the harness..."

No, other than a black "wrap" material the factory installed over part of the battery cable...but I think it was more of a "anti-scuff" type loom material. The wires to the solenoid, of course, were wrapped in wiring harness wrap material..thin stuff.

You probably need to start getting creative if this area of the wiring harness bugs you....if there is "a problem" then figure out something that will protect the wiring and stay hidden (if not seeing something non-stock bugs you). There are all sorts of real nice heat shielding/wire shielding material you can buy in MANY forms (sheets, tubes, etc) from places like Summit Racing. Brands such as DEI, etc. Your options are pretty much endless in that regard.
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Old February 3rd, 2019, 12:20 AM
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When I look at the sketch again the wiring harness that passes through the plastic tube looks very thick. Mine is barely the thickness of a battery cable. Is this just a bad drawing or was there some additional insulation over the original battery cable?


Last edited by tcolt; February 4th, 2019 at 02:22 PM.
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Old February 3rd, 2019, 12:05 PM
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Ok - sounds like a routing problem as you mention.

In the ILT/MotorCity drawing above you can see where the pos batt cable runs over to the block. Right where it meets the block area you can see it disappears behind/to the R side of a bracket. That bracket is a starter support bracket that attaches to the outside of the starter case (on the lower end of the bracket) and then attaches to the block (on the upper end of the bracket - you can see the drawing shows a bolt head at the top of the bracket). The cable (and wires coming down from above) get held in place, in a way, by this bracket....it keeps them tucked up nearer to the block and over the solenoid instead of these wires/cable just flopping around moving in the space b/n the block and the inside-facing surfaces of the exh. manifold.

BUT - to use this bracket your starter case needs to have a small threaded hole in it to attach the lower part of the bracket.

This bracket, I believe, was only used on big block cars but I'm not 100% sure....they may have used a longer/heavier starter. But the bracket should also work on small block cars as long as there is a boss cast into the side of the block to attach the upper end of the bracket and you have a starter with the small threaded hole in it to attach the lower end of the bracket.

Many starters have this threaded hole in the case IMO....here's a pic of a 350 Olds starter I have and the threaded hole is there.

ILT sells the support bracket and attaching hardware or you can probably find a decent used brace, etc on this site:

68-72 Olds Starter Brace INL11094 $22
Starter Brace Hardware INL12199 $6 - (NOTE: the "hardware" is just two bolts and a flat washer...easily sourced locally if need be)

The ILT catalog description does list this as working on 350 and larger motors for those years.

Last edited by 70Post; February 3rd, 2019 at 12:11 PM.
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Old February 3rd, 2019, 12:48 PM
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Patton, the brace for the starter was used on both 350 and 455 engines in 72. This is a file picture from when I rebuilt my starter (72 Cutlass S 350) Here is the brace; It's the curved shaped piece above the solenoid in this picture. Oh, the starter cable tube? The OEM was a phenolic material which is highly resistant to heat. Garolite is a brand name of the product. It's composition is fibreglass epoxy laminate.

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Old February 3rd, 2019, 12:59 PM
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OK. Thank you both. I think this could be the answer. I am missing both parts, but I also feel like the three individual starter wires should probably be inside some sort of rubber sleeving as it passes under the starter bracket. Is that correct?...
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Old February 3rd, 2019, 01:12 PM
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This is the extent of the starter wire protection on my car. It's all OEM. Picture taken just prior to bolting in place and securing the brace. You can clearly see the limitation of the 'rubber protection'. Below picture is before removing the starter. it shows the detail a bit better but with crud on it.





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Old February 3rd, 2019, 01:34 PM
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Thanks for those pictures Allen. Wow! So there really is nothing at that point and the wires simply run within about 1/2" to the hot exhaust manifold. When I had my wagon idling for 1/2 hour the other day my wires just were glowing red hot and the insulation melted away, even with an aftermarket rubber sleeve that covered them. That also got fried and crumbled away. It's possibly that the engine was a little too hot because it was lo on coolant, but obviously that can happen sometimes and shouldn't cause a wiring meltdown.
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Old February 3rd, 2019, 02:18 PM
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It looks like my starter doesn't have the thread, but I imagine the brace would stay there even with just the top bolt, even if it does seem silly to spend $20 for a bracket that's not functional just because it's "correct"... :-)

Happy Superbowl!
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Old February 3rd, 2019, 02:38 PM
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Originally Posted by tcolt View Post
Thanks for those pictures Allen. Wow! So there really is nothing at that point and the wires simply run within about 1/2" to the hot exhaust manifold. When I had my wagon idling for 1/2 hour the other day my wires just were glowing red hot and the insulation melted away, even with an aftermarket rubber sleeve that covered them. That also got fried and crumbled away. It's possibly that the engine was a little too hot because it was lo on coolant, but obviously that can happen sometimes and shouldn't cause a wiring meltdown.
Tens of millions of Oldsmobiles were built with V8s and the same wire routing. There was not a widespread recall for this. It is not normally a problem. The wires only glow "red hot" if there is a massive short.
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Old February 3rd, 2019, 02:42 PM
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Your starter may have been replaced at some time in the past with another brand name one? That may explain why the bracket is missing and the starter housing isn't tapped. I don't know why your wires would be that close to the hot exhaust to glow red, and that's not good because I believe they will lose some of their conductivity due to that condition. My wires stay quite a bit more than that away from the e manifold and exhaust.
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Old February 4th, 2019, 12:39 AM
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I'm certain that my starter was replaced at least a few times, but I still can't see how the wiring would feed in much differently than from the rear of the left manifold and along the starter solenoid to the front of the solenoid where the wiring terminals are. Here are some pictures and you can see that there is probably only an inch between the exhaust manifold and the solenoid and the wiring runs in that space. Allan's pictures seem to confirm this and it looks like there is about 1/2" between the wires and the manifold. I can only think that my manifolds were getting much too hot for the wiring insulation to get burned off like that. And it's not from a short because the starter still works fine and also I'm pretty sure this was not the first time I noticed smoke coming from that area. I could only imagine trying to run the wiring tucked behind the starter solenoid, but that also seems like a Mickey Mouse solution....




Last edited by tcolt; February 4th, 2019 at 10:37 AM.
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Old February 4th, 2019, 12:45 AM
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My best guess would be that my engine is running way too hot and that I need to move the wiring closer to the starter. Obviously, at this point I have to replace the burned wiring. I will also get the tan battery tube even though I don't think that's the main problem.

Does anyone happen to have a cheap used starter bracket as shown in Allen's pictures? I don't think it's really worth putting a nice new $30 bracket in there at this point...

Thanks, Tom
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Old February 4th, 2019, 05:55 AM
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Originally Posted by tcolt View Post
When I had my wagon idling for 1/2 hour the other day my wires just were glowing red hot and the insulation melted away...
Tom, retarded timing at idle will make the manifolds incredibly hot. Is your idle timing Ok?
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Old February 4th, 2019, 08:47 AM
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Originally Posted by VC455 View Post
Tom, retarded timing at idle will make the manifolds incredibly hot. Is your idle timing Ok?
Thanks Gary. I''ll check. All I did from a well running engine to a not so well running engine was switch to a 4 barrel manifold and stock, correct, rebuilt carburetor and I haven't connected any of the vacuum hoses yet, so it's a possibility... Do these cars have vacuum retard type distributors?... I've never touched the ignition yet except for changing spark plugs last week.
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Old February 4th, 2019, 02:23 PM
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Originally Posted by tcolt View Post
When I look at the sketch again the wiring harness that passes through the plastic tube looks very thick. Mine is barely the thickness of a battery cable. Is this just a bad drawing or was there some additional insulation over the original battery cable?

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Old February 4th, 2019, 02:48 PM
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Back to Brandon: he sells many parts and may have the bracket as well. Give him a call and ask. If not you try pacrat for the bracket or you can get just the bracket from other suppliers. Both these guys are gentleman.
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Old February 4th, 2019, 02:53 PM
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Bad drawing. Your analysis is correct - just the width of the cable.
Here is a full page scan from my 72 Cutlass Assembly Manual. Maybe it will help you with your routing and battery tube issue? If I scanned it right, you should be able to enlarge it as needed for better detail.

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Old February 4th, 2019, 03:02 PM
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Originally Posted by zeeke View Post
Back to Brandon: he sells many parts and may have the bracket as well. Give him a call and ask. If not you try pacrat for the bracket or you can get just the bracket from other suppliers. Both these guys are gentleman.
For your convenience I have already linked their profiles to a PM if you want to contact any of these guys. All have parts, and I've listed them randomly as they all are great guys and straight shooters.
Oldspackrat is Scott Winn
442crzy - Nick Z
jensenracing77 - Eric Jensen
2blu442 - John McNeel
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Old February 4th, 2019, 06:02 PM
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Thanks for hanging in there with me on this question. Allan, I'd already asked two of the parts guys that charge less than the regular vendors and am waiting to hear back. Much appreciated a well..
Your drawing is a lot better and if the lower left hand drawing is for cars with AT (AMT?) then I might imagine that the cable comes out of the phenolic tube and to the left, is that the starter bracket that's visible between the tube and the rear edge of the manifold? If so, then it would confirm that my routing was roughly correct although not tucked away from the manifold enough to avoid being incinerated :-)
I also notice what looks like collar or sleeve around the cables, just before the starter bracket. Can anyone confirm that part was really used at the factory?

I had to look up what the timing is for my car (12 BTDC) and which one is the number 1 cylinder on these engines, but it looks like I have to fix my starter wiring before I can check the timing. Is it likely that I can't really check anything right until I have the vacuum hoses on the carb and intake hooked up first?...

Last edited by tcolt; February 4th, 2019 at 06:28 PM.
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Old February 4th, 2019, 06:23 PM
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Originally Posted by tcolt View Post
Your drawing is a lot better and if the lower left hand drawing is for cars with AT (AMT?) then I might imagine that the cable comes out of the phenolic tube and to the left, is that the starter bracket that's visible between the tube and the rear edge of the manifold?
That bracket you're referring to is the bracket that holds the Phenolic tube to the frame. There's a clamp that goes around the phenolic tube that's screwed to the bracket, and the bracket is screwed to the inside of the frame rail. I know it looks different in pictures. This is exactly how my wiring is routed on my 72 Cutlass (TH350 trans). I don't have any clearance issues or heat issues with my wires, or interference from the exhaust manifold.

Originally Posted by tcolt View Post
I had to find out what the timing is for my car (12 BTDC) and which one is the number 1 cylinder on these engines, but it looks like I have to fix my starter wiring before I can check the timing. Is it likely that I can't really check anything right until I have the vacuum hoses on the carb and intake hoked up first?...
The #1 cylinder is at the front of the car on the drivers side. Here's a picture that shows the firing order of the Olds engine.


Note the rotation of the distributor is counter clock wise.
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Old February 4th, 2019, 06:26 PM
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PM sent on starter bracket and original tube and bracket.
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Old February 4th, 2019, 06:29 PM
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Originally Posted by 442crzy View Post
PM sent on starter bracket and original tube and bracket.
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Old February 4th, 2019, 06:54 PM
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[QUOTE=Allan R;1152612]That bracket you're referring to is the bracket that holds the Phenolic tube to the frame. There's a clamp that goes around the phenolic tube that's screwed to the bracket, and the bracket is screwed to the inside of the frame rail. I know it looks different in pictures. This is exactly how my wiring is routed on my 72 Cutlass (TH350 trans). I don't have any clearance issues or heat issues with my wires, or interference from the exhaust manifold.

What is that sleeve closer to the engine?
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Old February 4th, 2019, 07:05 PM
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Originally Posted by Vintage Chief View Post
You're correct about 12 BTDC. But, 12* BTDC is after you've established the dwell angle which should be, I believe, 30* w/ #1 cylinder @ TDC. It's in your CSM or on the radiator shroud tag.
Your starter & starter solenoid need to have the correctly sized wires - hopefully you have the original wires. They're color coded in your CSM wiring diagrams. If you're uncertain about the type of wires, etc. the CSM provides a couple of checks for excessive resistance with the starter motor in the Chassis Electrical system of the CSM.

When you perform your tune-up, you should ensure the vacuum hoses are all connected correctly for optimal performance & tuning.
The correct tune-up procedure is Dwell Angle>Timing>Carburetor. You'll unhook the distributor vacuum advance hose & plug it when setting your timing. If you're setting up your car for a daily driver, you should ensure all your vacuum hose lines are connected correctly while performing the tune-up. If you're more or less a 'work-in-progress' until you get all the hoses in the correct locations, you'll need to ensure at a minimum you have the PCV emission vacuum lines plugged. NOTE: you'll certainly need the vacuum line from the AT modulator connected correctly in order for the car to shift properly. I believe the AT modulator is connected to the intake manifold - I can't recall honestly, it may be connected to a vacuum source on the bottom of the carburetor - look in your CSM.

BTW, do you have the OEM DVCS valve in your car? Was it removed? Was it bypassed? Does a 1972 use a DVCS switch? I have a 1971 sbo 350 but I removed my DVCS and I have it bypassed.
I don't know what a DVCS is, but I think everything is still there. I don't know if it's functional and it's not hooked up to anything. I'm only trying check my timing for now to see it is way off....
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Old February 4th, 2019, 07:39 PM
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[QUOTE=tcolt;1152620]
Originally Posted by Allan R View Post
That bracket you're referring to is the bracket that holds the Phenolic tube to the frame. There's a clamp that goes around the phenolic tube that's screwed to the bracket, and the bracket is screwed to the inside of the frame rail. I know it looks different in pictures. This is exactly how my wiring is routed on my 72 Cutlass (TH350 trans). I don't have any clearance issues or heat issues with my wires, or interference from the exhaust manifold.

What is that sleeve closer to the engine?
The "sleeve" is a tar (or something like that) impregnated loom material that is slipped over the lower part of the battery cable BEFORE and connectors/tabs are crimped on. REPRO battery cables have this loom/sleeve material installed on them (on cables/applications that originally had it which yours likely did). The typical parts store replacement cable will not have this loom/sleeve.

It's not like it's a super heat shield sleeve material...in fact it may be a woven cloth or paper material that has the black coating on it. More likely it was on there as an "anti-rub"/anti-vibration sleeve.

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Old February 4th, 2019, 08:23 PM
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[QUOTE=70Post;1152627]
Originally Posted by tcolt;1152620/

The "sleeve" is a tar (or something like that) impregnated loom material that is slipped over the lower part of the battery cable BEFORE and connectors/tabs are crimped on. REPRO battery cables have this loom/sleeve material installed on them (on cables/applications that originally had it which yours likely did). The typical parts store replacement cable will not have this loom/sleeve.

It's not like it's a super heat shield sleeve material...in fact it may be a woven cloth or paper material that has the black coating on it. More likely it was on there as an "anti-rub"/anti-vibration sleeve.
I don't know why that quote came under my name because it's the OP's question, not mine.

Anyway, here's a better picture of the battery cable and protection


I found this stamped to the boss where the starter bolts up. I have no idea what the numbers mean though. Anyone who knows, it would be a great bit of information I can document to my car


Pictures of the phenolic tube that came out of my car - before and after cleanup.

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Old February 4th, 2019, 09:16 PM
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Originally Posted by Vintage Chief View Post
The discussion of the DVCS (if a 1972 has one) is located in the Engine Cooling section, but you'll also see a picture of it on the top of your intake manifold in the intake manifold section of your CSM. Many owners have bypassed the DVCS. If you're looking for a judging points value restoration you would have one, if you're not interested in a points value competition judged vehicle, then bypassing the DVCS is appropriate. You just need to ensure you have the AT modulator hooked directly to intake manifold (no T-connector off to the DVCS), and the back of the carburetor & front of the carburetor vacuum sources plugged since they won't be feeding the DVCS. If you need more help, we'll get you there.
I actually got my CSM in the mail today and found it. Haven't checked enough yet to find out if it will tell me what color code vacuum hose I have to buy. Basically, I wouldn't mind hooking everything up as it was, but for testing purposes I can also bypass it. Does the car run better without it or does that mostly eliminate the chance of something going wrong when they fail? Of course I also don't know if mine is still functional and the temperature sending switch too. To insure reliable running for now, it's probably better to start off without those components, so I'd appreciate any pointers as to what ports on the carb should be plugged and which will be used.

I just looked at the DVCS and that it's supposed to advance the timing on a hot engine and in third and fourth gear. I'm not sure why or whether I would need that with my 2004R transmission with lockup torque converter?...

Thanks for the description about the wiring loom Patton. It looks like I'll do without that sleeve for a while.

Last edited by tcolt; February 4th, 2019 at 11:59 PM.
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Old February 4th, 2019, 09:38 PM
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[QUOTE=Allan R;1152632][QUOTE=70Post;1152627]I don't know why that quote came under my name because it's the OP's question, not mine.

Anyway, here's a better picture of the battery cable and protection



Is this the positive battery cable with two cables ending in one terminal. It looks like the other red and yellow solenoid wires would be separate or are they packaged into the same harness and through the phenolic sleeve ttoo?
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Old February 5th, 2019, 09:51 AM
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Thanks for the good info Norm! That's what I meant by timing being way off. Still running well enough, but enough to cause it to run too hot. I'm not sure if I still own a dwell meter. I used to use a feeler gauge on my German cars. Does that not work on these?

Thanks for telling me that the purpose of the DVCS and the timing advance is to increase fuel economy. Funny, I always thought that advancing timing does the opposite by increasing performance (within limits...). I should have probably said that the 2004R never originally came with these cars, but was a common "upgrade" from the eighties. So, the question is whether I even have a vacuum output on it that transmission that could tell my DVCS that the transmission is in 3rd and 4th gear. I might be able to take the signal from the lockup torque converter, but I don't enough if that's enough to make the switch operate.... Hopefully Joe and the other 2004R experts can chime in on that. The reason I asked about color coding is because I try to do everything as close to correct looking when it's easy and cheap to do. Maybe these engines only used one color code and that was black with a white stripe? A lot of places sell the color coded vacuum hose, so I thought my 350 should have had some color coding?...
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Old February 5th, 2019, 10:08 AM
  #39  
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A couple of things need to be cleared up in this thread. First, to the original question about the tabs being used for MT cars only, as the PIM drawing that Allan provided in Post #26 shows, that statement ONLY refers to the battery cable routing. As shown, MT cars route the battery cable over the valve cover to keep it away from the clutch linkage. AT cars don't have that issue and route the battery cable along the inner fender. The clips are STILL used on AT cars for the wire harness that runs to the oil and temp senders (and to the alternator on A/C cars). The clip on the center valve cover bolt is also needed on O.A.I. cars to anchor the spring that holds the air cleaner adapter.

Second, the dwell angle in the distributor is completely unrelated to TDC or timing. You can set the dwell with the distributor out of the engine.

Third, the DVCS is part of the Transmission Controlled Spark system. I don't know why, but people are regularly fluxomed by TCS. TCS is an early emissions control system that inhibits vacuum advance unless the transmission is in high gear. TCS is intended to reduce NOx emissions, but at the expense of poor low speed performance and potential low speed overheating. This is why the DVCS also incorporates a temp sensor that allows the system to bypass the TCS (and ported vacuum) and run the advance directly from manifold vacuum. Advancing the timing at low speed helps the engine run cooler and also improves driveabiltiy - which is why many people disable the system. FYI, if you simply unplug the wire from the DVCS, the system defaults to vacuum advance all the time, though in this case it is ported vacuum, not manifold vacuum.
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Old February 5th, 2019, 11:08 AM
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Originally Posted by joe_padavano View Post
Third, the DVCS is part of the Transmission Controlled Spark system. I don't know why, but people are regularly fluxomed by TCS..
Thanks Joe. I'm definitely one of those people since there are a lot of firsts for me with this engine and me being used to only inline 6s.

I'm not interested in reducing NOX or heating my engine up more than it has to. The way I think I understand you is that the system basically is bypassed in the higher gears and the engine would run just the same as it would if it wasn't there at all. At lower speeds/ temperatures/ gears it changes the timing to reduce Nox at the expense of driveability. I'm not sure where the fuel economy gains come in? If there is no real benefit for me nowadays and there is no other gain from the DVCS / TCS at cruise speed, I'd be inclined to hook it all up, but unplug the temperature wire as you said. What about your point of it going to ported, but not manifold vacuum? Do I need to worry about that?

Norm, it seems silly for me to ask about color coded vacuum lines, but I try to do stuff to my car so that it's close to factory when it make sense to me and doesn't cost much money. I've seen all these offerings of vacuum hose kits for GM cars, but so far I can't even tell from the manuals that there was anything color coded on the 350 engine. Maybe you know where to look for that?...

Last edited by tcolt; February 5th, 2019 at 11:10 AM.
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