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Wedge TR8 Charging Voltage at 15.9

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Randy, Lots of questions and much to say about your pic.
Tomorrow as I have had way to much wine to type all of it
 
Started off with an inexpensive table wine to help in the pre dinner manufacturing and finished with a nice Rose as it was a warm day yesterday and a Rose is perfect for that.


InsideBatteryCableterminal.jpg


Todd, when I run my new cable I want to eliminate this connection an put it in the engine compartment with a better terminal. Is there a way to do this? Where do those brown wires go? To the fuse box?
 
you could do what I did. I ran the battery cable directly to the starter and then ran one from the starter to a fuse block I installed in the TR7 battery tray to fuse and divide out the major branches. One to the original fuse panel, one for fog lamps+fans (a trouble shooting aid), one for the auxillary fuse panel I installed and one for the electronic ignition. I paid about $15 for a fuse block out of a Mazda with 5 fuses. Leads are screwed into the block and wont come loose. I had photos somewhere but can't find. one day I'll drop by and show you.
 
Phil, Must have been the wine last night. I need a map!

Also is your battery in the trunk
 
That is the factory splitter for the brown(constant power) wires. There is suppose to be a black plastic cover that snaps over it. It works well, I wouldn't mess with it, unless you do run the new cable to a junction point inside the engine bay. There is a bundle of white wires(switched power) above the fuse block that most people don't know about. If you do away with the brown junction, you will have to run wires back to each one of those smaller brown wires anyway. I'd leave it be and would even try to cut it into the new cable if possible. If you are missing the black cover, I could dig thru my stuff and see if I have one. In the mean time, cover it with electrical tape before you short something/everything out.
 
No I have the cover on mine as does Randy. what do people do who run a new cable?

Though if you look at Randy's photo I don't have that clear or white junction thingy.

I also don't have the brown wire out of the bottom either. My bottom wires run to my before talked about fuse panel to power the relay for the fuel pump
 
I don't know of anybody with a TR8 running a new cable, seeing how it is already there. On a TR7, when you are relocating the battery to the trunk, a similar junction is located in the engine bay since that is where the battery was located. Hypothetically, if I were to run a new cable using an otherwise stock TR8 wire harness, I would reuse the factory splitter in the original location before heading to the starter with the new cable. I would also take off an additional wire to supply power to a secondary block in the engine bay.
 
So instead of my Terminal like this
pdb4.jpg


in the engine bay, put it in the passenger foot well and then run another off of it to the starter?
 
My plot thickens. I have not replaced the alternator yet....

Just for kicks I checked the voltage at the battery again. 15.9 volts

I turned on the headlights & fog lights and checked again. 13.4 volts.

If the regulator was bad, wouldn't I get 15.9 volts with everything running?
 
GBRandy said:
If the regulator was bad, wouldn't I get 15.9 volts with everything running?
Click to expand...
At idle or at cruise rpm? Even alternators don't necessarily keep up with the headlights at idle; especially those old Lucas alternators.

PS, I would still expect the voltage to drop somewhat with the headlights on, even with the engine at 3K rpm and the (failed) regulator calling for full output. 15.9 means the battery is being WAY overcharged, so anything that reduces the amount of charge (like some of the current being diverted to the headlights) is going to drop the voltage.
 
Oh, one other point, your battery may well be toast by now as well. That kind of charging is NOT good for them! If your new alternator still acts funny, it may be the battery.
 
It was at idle....700 rpm. I did not have a helper to rev the engine so I could see if it jumped back up to 15.9.

I am going to replace the alternator...but the car is acting oddly on occasion and I need to get this sorted as I am concerned an larger underlying problem is at hand.

I moved the key into the "run" position (just prior to starter engage position)and for a brief instant it seemed like the starter engaged. It has not happened in many re-tries....but....

How about this: Car running. Radio on. Turn ignition key off. Radio shuts down. Power antenna retracts. Take key out of ignition and place in pocket. Push power button on radio. It turns on...WTF.
 
GBRandy said:
I moved the key into the "run" position (just prior to starter engage position)and for a brief instant it seemed like the starter engaged. It has not happened in many re-tries....but....

How about this: Car running. Radio on. Turn ignition key off. Radio shuts down. Power antenna retracts. Take key out of ignition and place in pocket. Push power button on radio. It turns on...WTF.
Click to expand...
These both sound like ignition switch problems to me. I've had a more severe form of the first happen on my Stag : driving down the road and the starter came on! Applying just a little pressure on the switch away from the 'Start' position let the starter relax even after the pressure was removed; but jiggling the switch in the other direction would cause the problem again. Replacing the switch solved the problem.

Second problem sounds similar, too, but an unintended connection to the 'accessory' pole instead of the 'start' pole.

So I'd pull the switch out and examine it. Might just be a tab broken or some other problem that could be fixed without replacing it. But I'd deal with the alternator first, unless your switch symptoms become more severe (like finding a dead battery in the morning).
 
GBRandy said:
I moved the key into the "run" position (just prior to starter engage position)and for a brief instant it seemed like the starter engaged. It has not happened in many re-tries....but....
Click to expand...

Randy -

Mine did that a while back, and it was due to improper wiring of the oil pressure sending unit. There are three wires there, and if not correct, the starter will have a mind of its own!

But yours is FI, correct? Not sure if it has the same sending unit....
 
TR3driver said:
These both sound like ignition switch problems to me. I've had a more severe form of the first happen on my Stag : driving down the road and the starter came on!
Click to expand...

My car did that as well about 4 year ago and I replaced the switch assembly. Guess it is happening again. Thanks for the reminder as I was focused on what I might have done during my interior refresh.

Coincidence or not, but new carpeting has cost me an alternator and an ignition switch. :crazy:

I won't have much time between now an Sunday to look at things so I'll report back then.
 
GBRandy said:
I did not have a helper to rev the engine so I could see if it jumped back up to 15.9.
Click to expand...
BTW, here is my favorite electrical "helper":
https://www.radioshack.com/product/index.jsp?productId=2062661
Use them to make your meter connection, and bring the meter out so you can see it from the driver's seat (or wherever).

I actually went a step further and made up a length of lamp cord with quick connects and alligator clips at one end; and pin jacks at the other end for the meter leads (one of my sets of meter leads are designed to mate with pin jacks). That makes it trivial to connect the meter semi-permanently, bring the lamp cord out from under the hood and locate the meter inside the cabin so I can take a drive with it connected. Very useful for troubleshooting intermittent problems!

Looks like pin jacks have become obsolete, though, I couldn't find a photo on the web. So maybe today it would make more sense to use banana plugs (assuming your meter will take banana plugs).
https://www.amazon.com/Parts-Express-Banana-Plug-Red/dp/B0002KR39O/ref=sr_1_72
 
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