Restoration of a 1987 Bertone

Revving the motor does not make the needle move at all. I held it at 3,000 RPMs for a while and the needle didn't move. I know the gauge works because when I put a battery charger on the battery, the needle jumps up to mid range. I guess I need to check some voltages.
 
Revving the motor does not make the needle move at all. I held it at 3,000 RPMs for a while and the needle didn't move. I know the gauge works because when I put a battery charger on the battery, the needle jumps up to mid range. I guess I need to check some voltages.

Adding or subtracting load (headlights, heater blower, etc.) should make the needle move, which would at least verify the gauge is detecting a variance in voltage, which I guess is a start.
 
So the real arbiter is a multi meter. On my 85 which I am driving with regularity, the gauge always reads at half or below.

So does this mean that the alternator is not putting out what it should?

No.

On my car, after the timed lights go out and the car is revved to excite the alternator and I check the battery posts with the car idling I get 14.06v. This is with the gauge showing about 1/2 way or maybe a little below.

Turn on the lights and rev the car to 2500rpm, 14.2v, turn on the high beams and it drops to 14.06v again but the gauge throughout this is now at the 1/4 mark.

On my car the idle sometimes drops a bit more than it should so with the lights on and the idle low it will drop to below 13 with the gauge showing about 1/8.

So the moral of this is, use a multimeter to find out what is really going on and calibrate in your mind what the gauge is telling you, the absolute position of the needle relative to the gauge face is not indicative of the exact voltage that the car actually has available. If you really want to know I would suggest adding a digital gauge in place of the clock (or get Bob Brown to help you put one in the instrument panel) and run the wires to the actual battery where the load is being drawn from and replenished by the alternator.

The multimeter will tell you if you are running at a lower voltage than you should. If you are, I would measure back at the alternator to verify what is actually being output. If that is good I would measure back at the starter to verify a good connection between the alternator, the starter post and the main battery cable. Once you know those are good then the issue is back at your battery connections be it the positive or the negative. Taking each one off, cleaning it and applying dielectric grease and reassembly wouldn't be a bad idea.

Hope that helps at least a bit. The gauge lies, all gauges lie. They are just indications of what is really going on.
 
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Okay this is weird. If I rev it to 4,000 RPMs then the gauge moves up to half way where it should be. But as soon as I hit 4,000 RPMs the engine starts running rough and acting like it's missing. Even when I drop back down to idle, the gauge continues reading but the engine continues running rough and won't even out.

Shut it off and start it back up and it runs smooth but the gauge is barely in the white. Rev it back to 4,000 RPMs and repeat.
 
Whoa! Now that really is odd... Is this a new alternator or the one that came on the car?

New alternator from MWB. I played around with the timing and have it running better now but still not perfect. Put a timing light on the bellhousing opening and timed it to exactly 10 degrees btdc and then tweaked it from there. It now runs very smooth except when I rev it up and hold it, I can hear little backfires. But at least I know it's charging so that's one less thing to sort out now.
 
So if it isn't charging related, then my next go-to is the vacuum line between the manifold and distributor. Next the actual diaphragm inside the distributor. Both of them go bad and then you get weird behavior at one or the end of the RPM spectrum...
 
So if it isn't charging related, then my next go-to is the vacuum line between the manifold and distributor. Next the actual diaphragm inside the distributor. Both of them go bad and then you get weird behavior at one or the end of the RPM spectrum...

I know the vacuum line is good, I tested it with a gauge. Could be the vacuum advance, I'll have to test it. It seems to run exactly the same whether the vacuum advance is hooked up or not. That's probably a good indication of a bad advance diaphragm.
 
I know the vacuum line is good, I tested it with a gauge. Could be the vacuum advance, I'll have to test it. It seems to run exactly the same whether the vacuum advance is hooked up or not. That's probably a good indication of a bad advance diaphragm.

Bingo.... You can also use the timing gun and see if the timing advances or not as the RPMs go up... Much easier than taking apart the distributor...
 
Advance diaphragm appears to be good. I can apply vacuum to the line and hear the mechanism moving. Also the timing light shows it advancing when revving. I was wrong about it running the same whether the vacuum was hooked up or not -- if I keep it at a higher RPM and unplug the vacuum, it definitely changes for the worse.

It starts fine and idles nicely. Now that I have the timing dialed in, the throttle seems quite responsive. However, I can hear the small backfires (poof poof poof) when I hold it steady at a higher RPM. If it was a points-based distributor, I would swear the condenser was bad but that can't be the case here. Weak coil? That seems unlikely. (cap, rotor, plugs, wires all new)
 
Interesting... My brain goes to fuel supply or spark strength. Does the poof poof poof noise sound like the engine is running too lean?? The ECU apparently uses a couple of inputs to determine the fuel pressure.. One of them it tweaks is the fuel pressure regulator. If that vacuum line is bad or if the supply is restricted it will run fine for a few seconds at a high RPMs and then start missing. I had that issue for a while.. I also had an issue with my coil just being weak after 30+ years. That made the car feel sluggish and I had lots of unburnt fuel, but it was more of a flooding type issue, not a high RPM miss...

Ed
 
I'm going to replace the coil just for grins and giggles to see what happens. Vacuum gauge reads good so I don't think it is a vacuum issue. Fuel pump, filter, and hoses are all brand new. The poof poof poof I hear sounds like a misfire to me but it could be fuel related.

I used basic plugs, I don't recall the brand but maybe NGK? I didn't splurge on any fancy ones.

By the way, is a top end chatter normal? Oil pressure is good and carefully adjusted the valves but I hear quite a bit of chatter coming from the cam housing. Some engines are just chattery so I'm just wondering.
 
Shouldn't that much valve train noise - if your valves are on the looser end of the adjustment range it will be noisier...

Before you replace the coil I would check the voltage to the ballast (and coil) at varying rpm's & make sure it's consistently over 12v (to the ballast) - if the voltage drops to the coil (beyond the normal created by the ballast) you can have spark related issues also...
 
By the way, is a top end chatter normal? Oil pressure is good and carefully adjusted the valves but I hear quite a bit of chatter coming from the cam housing. Some engines are just chattery so I'm just wondering.
These motors aren't especially chattery when the valve clearances are in spec, so if you're nervous it can't hurt to check a few things:
- what values did you use for the intake and exhaust clearances? Some editions of the Haynes manual have values that are wrong, too loose.
- Verify that you're getting oil into the valve area. Easy check, just lift off the valve cover and verify that each bucket is sitting in a pool of oil up to the level of the drain back holes. (I check this when I'm putting a motor together. Install the cam box with the pistons at mid stroke, add oil, spin the aux shaft with a power drill and verify that the oil squirter holes on top of the camshaft bearing surfaces in the cam box are squirting).
 
Car now moves and stops under its own power. But I haven't yet driven it out of the garage.

I have now completed
  • Engine tear down, clean, repair and replace necessary components, paint, reinstall
  • Transmission tear down and reassembly
  • Brakes
  • Suspension
  • Electrical
  • Rust repair
  • Speedo cable
  • Throttle cable
  • Radiator
  • Fuel lines
  • Coolant hoses
Now onto...
  • Body work and paint prep
  • Install new fancy adjustable shocks and get the stance right
  • Figure out why it won't stay in 5th gear !!!!!
 
Car now moves and stops under its own power. But I haven't yet driven it out of the garage.

I have now completed
  • Engine tear down, clean, repair and replace necessary components, paint, reinstall
  • Transmission tear down and reassembly
  • Brakes
  • Suspension
  • Electrical
  • Rust repair
  • Speedo cable
  • Throttle cable
  • Radiator
  • Fuel lines
  • Coolant hoses
Now onto...
  • Body work and paint prep
  • Install new fancy adjustable shocks and get the stance right
  • Figure out why it won't stay in 5th gear !!!!!
How did that poof poof poof misfire thing work out?
 
How did that poof poof poof misfire thing work out?

Oh yeah I forgot to comment on that. I timed it correctly with a timing light from the bellhousing and I replaced the electrical connector to the distributor. I had broken the connector when I dropped the engine and pieced it back together but I suspect it wasn't getting a good connection. Someone here was kind enough to sell me a replacement harness. After those two things, it now runs great.

I still have the odd problem of cold start, but only after it sits for less than 2 days. Since I ran it last night, I suspect it will be difficult to start now. But if I wait 2 days and then start it, it will fire up at the touch of the key. I will track it down eventually.
 
Took it to the end of the driveway and back a few times. Learned a few things:
  1. Clutch is very sensitive
  2. Brakes are weak. I've replaced everything and bled them twice.
  3. Car runs great!!
  4. Neighbors think I'm weird
 
If you installed a new clutch plate it may be after some break in it will feel OK. If you have not driven an X before you will think the brakes are weak since there is no booster. Always takes me a few minutes to get used to mine after not driving it for awhile. The X uses the same rotors and calipers as a 124 spider but a spider has power brakes and they work fine.
 
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