low battery after 6 month repair wait. Topic is solved

[oragex]

Pulling the alt looks like unfun.
Just reaching in with a hand is nearly impossible to check wiring, is there better access from beneath ?

Turbo engine is more cramped because of those hoses, but otherwise not that bad
www.youtube.com/watch?v=zlp6qvYBJMU

[jonesg]

I measured across battery terminals, engine off and idling, voltage drop when idling.

Also put meter in series at the neg post and get a reading with meter set on DC 10amp?
I think it says 6.4. Not sure if I'm doing it right or what the 6.4 is, volts? amps?

I haven't been able to get at the alternator terminals, is it easier from underneath?

[volvolugnut]

Can you remove the fan for better alternator access? It would not hurt to run without a fan while testing the alternator.
volvolugnut

[EngineeringBloke]

If the meter is in series, then it can measure (6.4) amps. Don't have it in series on a voltage range - that will damage the meter.

Check that there is a grounding strap from the back of the engine (near the timing belt side) to the fire wall. However, if the grounding is poor, I would expect many electrical problems to appear.

So it would be more likely to be an issue with the alternator, its rectifier or its voltage regulator. Perhaps its positive connection to the electrical system.

[jonesg]

Can you remove the fan for better alternator access? It would not hurt to run without a fan while testing the alternator.
volvolugnut

I'll have to... and it looks like a lot of stuff has to be moved to get at the alternator.
Intercooler hose and coolant hose block access.
I have a doctor appointment monday so I'm leaving it as is til after my appointment, I'll just charge it up.
later I can put it on ramps and see if its any easier from underneath.

I'm getting some sort of scraping noise in the serpentine area that I can't zero in on.
Thought the timing belt was scraping against the plastic cover.
I popped the timing cover off but it doesn't sound different in there idling.
put a screwdriver handle against steering pump, a/c compressor and alternator but they all sound smooth.

I plan to remove the serpentine belt, it took me all morning to find my T55 torx, I found it.
This is turning into a project.

[jonesg]

If the meter is in series, then it can measure (6.4) amps. Don't have it in series on a voltage range - that will damage the meter.

Check that there is a grounding strap from the back of the engine (near the timing belt side) to the fire wall. However, if the grounding is poor, I would expect many electrical problems to appear.

So it would be more likely to be an issue with the alternator, its rectifier or its voltage regulator. Perhaps its positive connection to the electrical system.

Yeh I think the alternator has to come out to do anything with it, I'll take a chance on regulator as its cheap enough.
There are no other elec problems, no warning lights in the array,
I broke the serpentine belt 2 yrs ago and the red battery light came on immediately. Not seeing that this time.

[jonesg]

Can you remove the fan for better alternator access? It would not hurt to run without a fan while testing the alternator.
volvolugnut

I'll have to... and it looks like a lot of stuff has to be moved to get at the alternator.
Intercooler hose and coolant hose block access.
I have a doctor appointment monday so I'm leaving it as is til after my appointment, I'll just charge it up.
later I can put it on ramps and see if its any easier from underneath.

I'm getting some sort of scraping noise in the serpentine area that I can't zero in on.
Thought the timing belt was scraping against the plastic cover.
I popped the timing cover off but it doesn't sound different in there idling.
put a screwdriver handle against steering pump, a/c compressor and alternator but they all sound smooth.

I plan to remove the serpentine belt, it took me all morning to find my T55 torx, I found it.
This is turning into a project.

I removed that ground strap and cleaned everything, also the 6 grounds on the fenders, no change.

I just drove it 20 miles on battery charge, when I got back theres a twittering sound, sounds like serpentine tensioner or something, I will pull the belt and listen again. I also opened the timing blt cover to have a listen, doen't seem to be there, I noticed theres a bit of belt drift on the cam pulleys.

I put a 5 second video up, you can hear the twittering too.

[jonesg]

I pulled the serpentine belt, theres a rubbing noise but the twittering went away.

Oddly, the red battery light didn't come on with the serpentine belt removed, it did when I broke the previous belt whilst driving.
Does this indicate something wrong in the circuit, such as bad regulator?

Anyway, I'm gonna remove the timing belt cover to investigate the rubbing noise, it goes away when rpm goes up above 1500rpm.

[jonesg]

rubbing noise seemed to go away when timing belt cover was removed, belt is wobbling on the tensioner pulley although the pulley itself looks steady.
There is a slight rub mark at the bottom of the plastic belt cover. thats probably the noise I was hearing.

Its a Gates timing belt. 60K miles maybe. changed the tensioner and water pump , idler etc at the same time.

[jonesg]

I took a pic of the plastic belt cover, rub mark at the tip of the screwdriver.
Fresh mark. just above crank sprocket.
is the belt shot already?