Starting problem - pls help me diagnose

[tomfreo]

Most of the time the beetle starts fine. Today however (and maybe twice over the last six months) when I turn the key I get a very slow groan at the back, the engine moves fractionally but nothing.

On previous occasions I thought I had a flat battery - put it on charge and the next day the bug started fine. Now I'm not so sure it's the battery.

Today I bridged the terminals on the solenoid and get the same very slow whir/groan. I believe that rules out a sticky solenoid.

I persisted for a while trying to get it to turn over then stopped and measured the voltage at the battery - 5.7V. I believe I simply drained the battery.

I put the charger on the battery and went inside to search the internet for a possible solution. Within ten minutes I came across the suggestion that I turn the engine over at the crank (with no explanation why this might help).

So within ten minutes of putting the battery on charge, I turn the engine over a bit, try the ignition, and boom the bug starts right up.

Come to think about it, I think the last time this happened, I bounced the car a bit while it was in gear and the bug started again.

Any ideas? All help appreciated!

(I should add I took the bug out to town, stopped and started several times perfectly fine. If I were to go out to check the battery voltage tomorrow, I'm sure it'll read some 6.3V)
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[Eric&Barb]

Clean both ends of both battery cables and apply dielectric grease before fastening back down. Do same with the body to transaxle ground strap. Replace any cables or strap if they look bad or have those clamp onto the end of the cable battery clamps.

BAD:

You want battery clamps that are swedged onto the cables or better yet soldered to the cables for a gas tight connection that does not allow battery acid fumes to get into to cause corrosion and voltage drop between each cable and clamp.

WW has the factory style battery cables with brass clamps soldered to the cables. The brass clamps last ten times longer than any lead clamp, so the higher cost in the end for proper factory battery cables is greatly offset.

Also clean/grease the terminals on the starter solenoid and connections between battery, regulator, gen/alt.
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In Stereo, Where Available!

[tomfreo]

Thanks for the suggestions. The wiring you mentioned is all AOK. In fact, I went through the wiring from battery to trans ground strap and everything in between with attention to starting/ignition only a year or so ago. That said, it might not be perfect.

The car starts immediately first time, always; except upon the few (three or four?) occasions described.

As I said, when I turned the engine over the car started straight away. (To be exact, I only turned about 270* at the crank so not exactly "turned over"). That the car started could be a coincidence. Perhaps there's a loose wire somewhere in the starting circiut? I doubt it however. I have a secondary ignition switch bypassing main loom and this showed exactly same symptoms.

I did have the battery on charge for, like, ten minutes (@3A yeah right). Maybe that warmed something up? I'll go outside and check the battery voltage. (Back) 6.29V. I realise this doesn't always mean a good battery

Perhaps there's a reason someone suggested turning the engine over in a post describing a problem like mine? Stuck engine? I had no problem turning the engine by hand. Primed the cylinders? No, this is a problem with the starter not turning the engine at all. No click, just a wheezy groan, that goes to nothing as I slowly drain the battery

I don't know the age of the starter/solenoid.

I don't know how starter/solenoid's work but would love a brief - specifically how and why they break down. Can the starter-solenoid give up one moment, and then spring to life the next?
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[tomfreo]

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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[carcrazed]

How old is your starter? Could possibly getting weak.
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1965 Herbie Replica. 1776cc dual Kads.
1961 Beetle 33,000 Original Miles

"Just When you think you are getting ahead, you're always wrong."

[Eric&Barb]

Doubt it is the starter or its solenoid. When those go bad they tend to stay bad.

What you have sounds more like an electrical connection. Could even be your ignition switch is starting to fail.
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In Stereo, Where Available!

[Luft kühl]

Your problem sounds like a worn starter bushing. This is the bushing located in the bell housing, not the starter.

When the bushing wears, the hole in it becomes oval shaped. This extra play in the solenoid plunger can cause the starter gear to become jammed with the flywheel teeth.

This could explain why the problem is intermittent, and it would also explain why manually turning the crank would free it up and allow it to work again.

[Eric&Barb]

[tomfreo]

Thanks for the help and ideas.

So I think I may have a bad battery. Same problem this morning. Before killing the battery I tested the voltage - 6.2V which isn't bad considering I'd just tried to start the car.

I measured the voltage across the battery while cranking (the engine didn't really crank, just groaned a lot as before) and it dropped to 2.32V. That's surely in the 'bad zone'.

I'm not entirely sure what I'm doing but read I should fully charge the battery and try a load test again.

Any thoughts?

BTW, curiously I whacked the charger on the battery in situ (just a dumb 3A charger), then tried to start the engine again and boom it fired right up. I would have thought a 3A charger would do nothing when asking for the tens? hundreds? of amps required by the starter??
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[Eric&Barb]

Your FLAPS should be able to check the battery for you, but it does not sound good.
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In Stereo, Where Available!

[tomfreo]

I charged the battery up yesterday. This morning the battery measured 6.37V after sitting for twelve hours.

Measured the voltage across the battery while cranking the engine. The engine turned over well and this time the voltage never dropped below 5.2V. Ignition connected, the engine started immediately.

At this point I should take it to a professional right? Get the battery properly load tested.

But maybe someone can help me here. Is it possible for the battery voltage to plummet (as in the first load test where it dropped to just over 2V) for any other reason than the battery being crap? That is, could the starter circuit, starter motor, etc cause the battery voltage to drop so low?

Or, is it common or possible for a battery to crap out cranking the engine (first test 2.3V) and then be fine (5.2V)? Or would this more likely point to a problem in the wiring or the starter circuit and/or the starter etc?

Battery experts?
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[David_nc_72std]

Are you measuring the voltage directly off the battery terminals? Sometimes there is a layer of corrosion on either the battery terminal itself, or the inside of the clamp on the end of the battery cable, and under high current loads that has enough resistance to drop the voltage and keep the starter from working. If you have a replacement connector that clamps to the battery cable, that can also get corrosion underneath the clamp and cause the same problem.

[tomfreo]

Thanks for the help. Yes, I am measuring off the battery posts. I take it you mean a starter load test of the battery is inconclusive until you can be sure there's nothing else wrong with the circuit, whether connections or with the starter-solenoid.

I'm getting a little ahead of things here but: assuming I
1) check and correct faulty connections/circuit
2) have the same 'engine doesn't turn over' problem and running a jumper from the battery to the solenoid doesn't make any difference, and
3) the battery has been tested OK on a load test at the local auto shop/FLAPS, then ...

I can maybe figure I have a problem with the solenoid or starter. Would that be about right?
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[Eric&Barb]

[tomfreo]

The PO installed a second separate starter and ignition switch at rear of bug. Whether attempting to start the bug from the cab or from the rear, the symptoms are the same. Both are bad when I have this occasional problem, both are good when I don't have this problem.

If you look at the diagram, the area encircled red is the rear (hacked) starter switch. There's very little in the way of wiring/switches to go wrong there.

Anyone got any ideas how I might be able to pin this problem down?
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[tomfreo]

So I went and got the battery load tested. I was surprised to see it done with a small handheld device. The guy said the battery passed 100%. When I asked if this was 'definitive' he said something sarcastic about the device being from the battery company and 95% of batteries tested fail.

Today the beetle has started flawlessly. I'm going to double-check all the connections in the shortest starter circuit before I decide it's the starter- solenoid.
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'77 Kombi 2L dual carbs
'61 Bug 6V 1600sp

[onlynavw]

I have the exact same issue with my Ragtop, replaced the battery, starter, and alternator... still intermediate issues, keep me posted on what you figure out!