So I disconnected the cable between the gorilla knob and the key. I like to pull the key and lock the column so I can leave it running. Not that I'm nervous it won't start again...

With the key off I'm still getting voltage from the alternator or battery, sometimes.

If I press the brakes I loose the fuel gauge and the charge light comes on. If I turn on the headlights I still have voltage and the fuel gauge keeps working. So my charging circuit is still letting a little voltage through? Everything shuts down with the motor. Im noticing my battery is draining a little overnight. Video shows the brakes first then the headlights.

Not a huge issue, but something's up.

Do you guys swap for a bigger alternator? Which one? With an internal or external regulator? Is the stock one really only 35 amps on a 220D? Preparing for this one to die. It got wet once and wasn't charging. I have an extra stock one, but...

If you know international ford diesel, you know what I'm talking about.

Shutting off the key shuts off the accessory circuit, what you are seeing is leakage keeping things going. Idling a diesel long term is a bad thing, it leads to wet stacking.

You think that leakage will drain my battery? Go to start this morning and it was dead. Battery held 12.5 volts so it's time anyways.

I've been reading about that, people skipping the warm up cycle. If it's more than a few minutes I shut it down. And now I'll have a new battery and less concern.

I'll have to start checking for voltage with the key off I guess. I'm not the best with this type of thing. I have a buddy that's an electrician but he's sounding like he went out last night. Lol.

' Wet Stacking'.... would you define that and explain the physics of which idling would cause it ?

I have seen pictures of mountain ski resorts where Mercedes diesels were clearly left idling overnight so they could be started in the morning...no snow on them....
Big rigs with sleeping units do this all the time... to run the ac or heat....

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/showthread.php?t=156207&highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

Oh yeah. Let's get this one going. I used to be the believer in letting it run. Spent some time in Canada in negative 40 F weather. Every truck at the grocery store is running in the parking lot. Everyone has manual shutoff rigged for this purpose.

Your 12.5 V test, was that after the battery was sitting for a few hours not doing anything?

12.66 for a lead acid battery is full charge. 11.70 complete discharge.

As for wet stacking, in the old days starters and batteries were not so good. Leaving them run was needed. If dealing with sub zero temps and no where to plug in over night, then idling is the only option. However, batteries and starters are better now making shut off possible.

Big trucks no longer let idle as this is hard on fuel for the amount of energy that comes off the motor. Large trucks now have a small diesel engine running a generator / AC compressor to provide energy when stopped. It has been illegal in many states to idle a over 5 ton truck more than 5 min for some time now.

Wet stacking occurs due to incomplete combustion ( cold cylinders ) at light loads. This allows carbon to build up in the combustion chamber, injector tips, exhaust valves, manifolds and muffler. You will also get fuel dilution and reduced engine life.

Guys that work on diesel back up generators / portable welders know all about wet stacking as these engines are frequently lightly loaded for extended periods.

12.5 after being on the charger. Either overnight at 2 amps or 10 amp quick charge (I know, but sometimes it has to be done).

I think these old Benz's have got to everyone. A modern car will charge a battery to 13.1-13.4. We checked my buddies toyota and his battery was 13.1

My alternator is charging at 12.65v.

A common thing in old fords is to swap in an alternator from a newer Taurus. 70amp to 135amp. I've been looking for info on this but haven't found any yet.

I'm stopping the rebuild shop next week, and have two alternators. I'm gonna go through their stock and look for something that will fit. If anyone knows what will swap in, I'm all ears. I need over 100amps.

So that's why you shouldn't warm it up? I've been letting it run a min after cold start and then go under light load until the needle starts to move.

We have that rule in california. Engine upgrades and all kinds of crazy stuff. I have the only isuzu made with 11,800 GVW, so I'm except.

But how do I find this drain? Should I be concerned?

I think you should be concerned because if it is a short... it can get worse..and if it gets worse it can generate heat and might cause a fire...

the electrical system is like a tree...
you disconnect everything... you add one branch back to the system at a time..and you isolate the item which is causing the drain...

__________________
1980 240d ,

chain elongation, cam marks reference:
http://www.peachparts.com/shopforum/showthread.php?threadid=10414

http://www.peachparts.com/shopforum/diesel-discussion/305365-9-degrees-chain-stretch.html

evap fin cleaning:

http://www.peachparts.com/shopforum/showthread.php?t=156207&highlight=evaporator

A/C thread

http://www.peachparts.com/shopforum/diesel-discussion/297462-c-recommendations-mb-vehicles.html

And do this with the engine running and the key off? When I find it the fuel gauge will turn off? The weird thing is this only happens with the engine running.

I highly suspect this alternator. It's from the junkyard motor. I'll try my fuses first, but maybe I should swap it to my other one.

Sometimes I feel like cutting this sob down and planting a new seed. Lol.

Also dealing with my clutch pedal not returning up. Checking the spring but I think the hose between reservoir and master is in need of replacement.

If you are checking immediately after removal from a charger, the voltage will be a bit high due to surface charge.

Charge, let sit for a few hours ( 8 is better ) then test voltage. 12.66 is full charge. This does not test capacity of battery, you need a load test for that. Think of the 12.66 being a full tank, a load test determines how large the tank is.


That is low, however if you just started the engine, the voltage will be low until the bat gets recharged. Test voltage after you have taken if for a 5 min or more drive.


Not all high amp alternators put out more amps at low speeds than a stock alt. You really need to see an amp vs RPM chart ( this will be alt RPM not engine speed so measure the pulleys and calculate ratios )

Modern alts use a double stator winding and two rectifier bridges. This Wye / Delta configuration gives you good low and high RPM charging..

Rather than going directly for the big alt, measure current draw with a amp meter. Do this for each accessory to generate your power budget.




You are doing just fine for the warm up. The wet stacking I'm talking about is frequently idling for 30 min +. In winter I start the engine as soon as I enter the car,( if needed scrape the windows), get settled then drive off.

Good point. I'm about to hit the road and will check charging when I stop.

I have a load tester, and knew this battery was on its way out.

I remember that now about the fords. That was part of the problem, only charging at higher speeds.

So I should start my search at the newer end of the spectrum, with mercedes first so I don't become Frankenstein.

Why do newer vehicles read over 13 volts? We tested a few that have been sitting and they all came out the same.

If you dig deep into the archives of AC Delco ( GM parts arm but now apparently independent ) Round about 1975 voltage regulator charging voltage went up about 0.75V.
This was due to the then new maintenance free batteries needing higher voltage to charge properly.

The 12.66 V full charge isn't an absolute number, a bit on either side is no cause for alarm and is just a guide. A car will start just as well on 75% charge as it will on 100% if the capacity ( load test ) is good.

Another consideration is the accuracy of your meter. You need a digital of decent quality. An analog meter on many load testers isn't very accurate due to most having an zero adjusting screw on the front.

That's interesting. I'll have to look into the difference in 123 alternators.

Mine alignment is slightly off and the pulley doesn't seem right. Odd thing is, both my original and donor are exactly the same. I saw this bracket on eBay, which I don't have.

I'm wondering if someone swapped a 123 setup in already. My car had a lot of 123 240d parts on it.

The next concern is diagnosing this voltage leak. I pulled all my fuses with it running and key off. I put fuel gauge fuse back in, and it was getting voltage. I put stop light fuse in and pressed on the brakes. Fuel gauge died.

My alternator for wet and some point and didn't work for about 10 min. Problem started around then. I have another alternator that looks new. Before I swap, I'm going to try unplugging it and running the car to see if problem still exist.

I've yet to kill this monster battery but it is loosing voltage overnight.

Thoughts appreciated. The day is coming soon that I'm on top of this car and won't be so lost. Lol.

To clarify my GM charging voltage change, it pertained to GM cars that got the new " Freedom " battery, as maint free batteries became more common, voltages went up across all manufactures. I don't know specifically when other makers raised voltages.