Duffy's 1/71 Series 1 240z build

[duffymahoney]

Having some running issues. My vacuum advance wasn’t operating correctly. 

Took it apart and cleaned it and the breaker plate. It didn’t move freely at all. It’s now moving nicely and lightly greased, vacuum holds fine  so it’s good. 

So It was affecting me tuning my carbs. 

Then my stupid flow meter broke.  I need to send it back. But I also bought a unisync. 

I am running lean. White spark plugs and intake backfire. 

I decided to do a compression test  numbers aren’t as close as I would like  

Compression

1-155

2-160

3-162

4-164

5-158

6-153

 

 

 

 

 

[duffymahoney]

Next is a leak down. I am at worst 8% off on my compression.  So for now that is fine, I’m sure the valves need adjusting.

I also bought a colortune spark plug (clear spark plug to see combustion color)

 

[Captain Obvious]

Work looks great and I'm no engine expert, but I wouldn't be too concerned with that range on the compression results. Certainly nothing that you would need to address in any hurry.

I do have a question about your alternator output though. That looks like a lot of charging... Does it make sense for your alternator to be pumping out 35A under whatever the drive conditions were at the time? Seems like a lot to me.

On ‎5‎/‎13‎/‎2018 at 11:26 AM, duffymahoney said:

 

[duffymahoney]

2 minutes ago, Captain Obvious said:

Work looks great and I'm no engine expert, but I wouldn't be too concerned with that range on the compression results. Certainly nothing that you would need to address in any hurry.

I do have a question about your alternator output though. That looks like a lot of charging... Does it make sense for your alternator to be pumping out 35A under whatever the drive conditions were at the time? Seems like a lot to me.

 Honestly don’t know! Seems odd for sure. This was cruising at 35 mph. Head lights were on. It’s the stock alternator 

[Captain Obvious]

Well the headlights should be drawing less than 10A total (probably around 8-ish), and all the running lights should be at less than that. I'm thinking you should have been around 15A plus whatever the battery was pulling. Maybe the battery was pulling a bunch? I'm thinking maybe the batter was partially discharged since it's not getting a lot of running time?

You running the heater fan and defroster too maybe?

Just seems odd to me... Most times I don't see an alternator needle swung that far over. Now of course, I've got the voltmeter on my later 280, so what do I know?

What say you 240 guys? Does it seem odd to see the alternator needle swung over that far?

[SteveJ]

Yes, it is unusual. The typical suspects are a battery going bad and loads added to the wrong side (battery side) of the ammeter.

[duffymahoney]

1 hour ago, SteveJ said:

Yes, it is unusual. The typical suspects are a battery going bad and loads added to the wrong side (battery side) of the ammeter.

This was after a full day of trying to start it.  So battery was most like dead.  Well hopefully.  I will check next time I try and run it.

 

I found my carbs were empty of oil.  I don't know why I assumed that the past owner shipped them with oil.  So that is my next step.

 

I will also make sure that TDC is 0 on my crank pulley.  Then work my way forward from that.  But I assume the carbs being out of oil is what was causing my tuning to be so incorrect.  Thanks! 

Edited May 15, 2018 by duffymahoney

[7tooZ]

Well the headlights should be drawing less than 10A total (probably around 8-ish), and all the running lights should be at less than that. I'm thinking you should have been around 15A plus whatever the battery was pulling. Maybe the battery was pulling a bunch? I'm thinking maybe the batter was partially discharged since it's not getting a lot of running time?
You running the heater fan and defroster too maybe?
Just seems odd to me... Most times I don't see an alternator needle swung that far over. Now of course, I've got the voltmeter on my later 280, so what do I know?
What say you 240 guys? Does it seem odd to see the alternator needle swung over that far?

Seems to me there is a big difference between a Volt meter reading and an amp meter reading on an early Z that is using a voltage regular.
My 240 commonly will kick up high on the scale and then will settle back down to a level more consistent to what I have turned on. I run a stock 71 alternator and regulator, relays to headlights and cooling fans and a gel battery.

I would put a full charge on the battery and the watch it on a long run of 10 miles or more while turning on different accessories.

Nice looking engine bay.


Sent from my iPhone using Classic Zcar Club mobile

[Zed Head]

I thought that the very high current was the reason it's not recommended to jump start a car with a completely dead battery.  The abnormally high current and subsequent heat can damage the alternator.  Not uncommon to lose an alternator after jump-starting a very dead battery.  Makes for some of those odd coincidental failure charging system stories.

[Patcon]

I thought your compression numbers looked good, well below 10%...

[duffymahoney]

Ok ran into tons of issues!

 

First was my vacuum advance was frozen.  So I took that apart and cleaned the crap out of it.  It's now greased and moves nicely. 

 

My biggest issue was the dizzy counter weights have these pins that slide into slots on the ears.  Well for some reason the previous owner thought it was smart to not have that hooked up correctly.  So everytime you stepped on the gas the timing would retard a lot!! Thus causing so many terrible issues.  It's now fixed and working like it should! The engine sounds night and day different!

 

Also go all my carpets bound to mass loaded vinyl.  The interior is night and day more quiet.  

 

 

[duffymahoney]

I put some holes in my carpet for my straps. I always thought they looked cool!