68 speedometer woes

[lambetti]

I recently bought a 68 beetle, and as expected, I’m working out the bugs (no pun intended,).
One issue is the speedometer was noisy, and speeds were reading low and not steady. I replaced the cable with new, and it seemed to get rid of most of the noise for about two miles, then it failed.

Got home, pulled the cable to find it snapped.

Plugged the old cable into the speedometer and I couldn’t turn it at all. The old cable actually spins fairly well when not connected.

So… looks like the Speedo is fried. Tried some silicone spray, no improvement.

The speedo PN is 113957023C
I found one with the PN 113957023D for $85

Can anyone tell me if this is OK, or should I hold out for one with the same PN?

Thanks!

[67rustavenger]

You could consider a speedo restoration.
https://www.thesamba.com/vw/classifieds/detail.php?id=875460

I recently bought a replacement for my 67 and I am disappointed with the functionality.
I doesn't read accurately other than the miles traveled.
_________________
I have learned over the years.
Cheap parts are gonna disappoint you.
Buy Once, Cry Once!

There's never enough time to do it right the first time. But there's always enough time to do it thrice.
GFY's Xevin and VW_Jimbo!

[cletus_zuber]

I'm guessing the 23D is a later model of speedo, maybe a 73 and up 100MPH or a black faced 90MPH. so would fit and be OK.

Look at the link Rustavenger posted to see the differences.

$85 for an unknown condition speedo seems high though.
_________________
1972 1302
HPMX 40's & 019

[meranda]

As I remember the 68 has a one year only speedometer.I would take it a motor instrument repair place.
_________________
Currently filling the garage
1961 beetle cabrio
1971 Superbug
1974 Porsche 911S Targa
1968 1500 Beetle A Project!
Past Garage fillers dozens of type1 &type3 VWs
Jaguar Mk5 & XK120
Lancia Flavia Coupe
Alfa Guilia sedan

[meranda]

As I remember the 68 has a one year only speedometer.I would take it a motor instrument repair place.
_________________
Currently filling the garage
1961 beetle cabrio
1971 Superbug
1974 Porsche 911S Targa
1968 1500 Beetle A Project!
Past Garage fillers dozens of type1 &type3 VWs
Jaguar Mk5 & XK120
Lancia Flavia Coupe
Alfa Guilia sedan

[Chinaclipper]

Ya know, I had this exact same issue with my 1971 rebuild. Is it the cable, or the speedo?
Here's what I did:
I bought a new cable, and poured some transmission fluid down the cable. Yes, trans fluid. I read somewhere that trans fluid is GREAT for lubrication of these cables.
I just used a cap to put the fluid in. Then you twirl it over your head like a cowboy lasso to get it to go all the way down (centrifugal force)
Well, I tell ya, that speedo is so smooth now, like butta'!

No skips or blips or oscillations at all, and at all speeds.
Done!
_________________
China Clippers Official 1971 Super Beetle Project!
https://www.thesamba.com/vw/forum/viewtopic.php?t=728089&highlight=

[viiking]

I have a 68 with the "one year only" speedometer. It's not difficult to pull apart and do a reasonable refurbishment job.

If you take your time and be reasonably gentle most people can do it.

More than likely the speedometer gears are either broken (low probability) full of crap or just have hardened grease.

There are posts on the SAMBA that show how to do it. It also gives you the opportunity to replace the gels on the indicator lights, clean the inside of the glass etc. Also if you have to remove the dial face, just be careful and use a proper sized screwdriver to remove the small screws. Nothing worse than seeing the screws all goobered up every time you check what speed you are going at.

The critical steps are splitting the body apart without doing damage to the bezel and most importantly removing and replacing the speedo needle without damage. Again SAMBA search is your friend.
_________________
1968 1500 RHD Lotus White Beetle since birth. In the hospital for major surgery
1966 Lancia Flavia Pininfarina Coupe - in the waiting room
Discharged: 1983 Vanagon, 1974 1800 Microbus,1968 Low Light,1968 Type 3

[lambetti]

As a follow up:
I had my speedo rebuilt by a business that advertises here on TheSamba. Speed registers close enough (35 indicated is actually 37 MPH).

I found that my fuel gauge is off by a quarter tank (3/4 indicated is actually full). Since I just got the car, I believe it was likely inaccurate when I bought it).

Electrical connections are cleaned.

Any ideas? Gauge or sending unit?
Or should I start a new thread?

Many thanks to all who responded.

[baldessariclan]

[lambetti]

[viiking]

You can certainly make a quick visual inspection of the sender unit float arm and bend this to get a better reading.

The way the gauge works is by a simple rheostat in the fuel sender. There are wire windings around a rectangular "former".

The float arm attaches to this rod which pivots across the windings from one end to the other. The further along the rheostat the pivot moves the more windings that are "read". As the resistance of the wire is known i.e. ohms/metre then the more wire that is read, the higher the resistance and vice versa. The gauge reads this resistance as a fuel level. In reverse from memory. Higher the resistance the lower the fuel level.

Now if you note on the second photo you will see that the windings are not uniformly separated. That means that if the pivot moves across say 5mm at one end, it will have a much different change in resistance than say 5mm at the other end.

VW engineers (or VDO the OEM suppliers) were very clever. You may notice that when the fuel tank is first filled it takes a fair while to drop down. This is the part of the float where there are few windings per 5mm or inch or whatever. Then you will start to see the fuel level start to drop quite rapidly and towards the reserve quickly as the windings become closer together. This is not a sign of massively increasing fuel consumption but the fact that a small change in the level has a BIG impact on the level shown on the gauge.

Most people when faced with this rapid decline in fuel level indication will be more likely to refill as the tank becomes less full. In addition the relatively more rapid change in level is more apparent than one that changes linearly.

So what to do?

If you can fill the tank so much better. When the physical tank contents is Full to your liking, then where the float arm rod pivot touches the windings it should be as close to the end as it can be. Then bend the rod arm to achieve this.

Now the issue is how low can you go. In most cases the bending of the arm should not affect the real empty reading. But you can check by physically dipping the tank when the gauge reads empty. Yes this is a hassle and means you have to take the sender out a couple of times but it is the only way to accurately measure the accuracy of the sender.

For the person with some mechanical skills, overhauling or replacing the sender is not difficult. In fact I purchased a new VDO sender and transferred all of the internals over to the original numbers matching outer mounting plate of the Jan 1968 sender. Yes the parts were still the same as they were 50+ years ago.

There are a number of posts on the SAMBA on how to refurbish the sender unit including the critical winding of new wire around the rheostat former. For this you need to have the correct ohms/metre wire to replicate the original. Use the search function.
_________________
1968 1500 RHD Lotus White Beetle since birth. In the hospital for major surgery
1966 Lancia Flavia Pininfarina Coupe - in the waiting room
Discharged: 1983 Vanagon, 1974 1800 Microbus,1968 Low Light,1968 Type 3

[hulbyw]

You can also get the sender windings re done at an instrument (speedo) repairer so no need to buy a sub standard repro

[scrivyscriv]

My orange Bentley isn't handy so this is info from the older blue Bentley; the manual more or less tells you to adjust the fuel gauge so that it shows empty when the tank is empty, and let the 'full' indication fall wherever it ends up.
It might be a challenge getting accurate indication for both extremes
_________________
Robert in Memphis
Dünkelgrügen 1967 Java Green bug thread
Engine rebuild thread
If you're ever in the Memphis area, you are welcome to stop by for advice and help.

[lambetti]

Some excellent replies here.

Grounding the fuel gauge wire moved the needle to “full”, telling me its the sending unit, so that is where Ill address.

I truly appreciate everyones help!

[baldessariclan]

[lambetti]

Well, I cleaned up ground points, and even added a ground wire (soldered lugs, grounded to chassis), no change.

I then pulled the sending unit (it does appear to be a factory VDO unit), and inspected it. Only obvious (possible) thing is the wire windings look dirty - perhaps from all those years of wear. Maybe this resulted in more resistance, resulting in lower readings.

I did bend the upper limit stop a little, but the wipe was pretty much at the top of the windings already. No change in readings.

So… I will either pull it, disassemble and clean, or replace it (a new VDO unit from Jbugs is only $50, but I love to tinker and fix things…). The biting cold got to me, so I slapped it back together for the time being.

Again, my sincere thanks.

[Matt Wilson]

I've experienced noisy and erratic speedometers. Each time, it was the little plastic odometer gear that aged and cracked and was slipping on the shaft. If you are delicate, you can carefully take apart the speedometer and inspect the gear, and pop on a replacement if needed. Some sellers will also have the new 'gels' that give the arrows their green color, and the warning lights red and hi-beams blue.

I've done a few of these, and they all turned out great!
_________________
1972 Standard Beetle
1969 Baja Beetle

[baldessariclan]

[lambetti]

All, I want to let you know my experience with that the vendor (who advertises on TheSamba) who I hired to fix my Speedo.

I probably shouldn’t name him publicly, but if anyone wants to know who it is, message me.

The good:
The Speedo works well, front is clean, pointer was replaced (added $25).

The bad:
The back was a dirty as when I sent it. Slight corrosion on terminals wasn’t addressed, etc. Not a big deal, and perhaps not their responsibility.
The green turn signal gel wasn’t replaced. It has what appears to be a rip. I would have gladly paid to have it replaced, given the opportunity.

The ugly:
The vendor sent me the wrong Speedo. I contacted him, he immediately got back to me, was quite embarrassed. He asked me to send the wrong one back, and he would reimburse me the shipping. A couple days later, I let him know the shipping cost and the tracking number, and he said he located mine and it was on its way.
I received mine, and asked if he was still willing to reimburse me, and he said yes.
A week later, nothing, so I sent a friendly reminder. Crickets.

If it were me, I would have not only immediately made good, i would have offered a little compensation for the trouble too.

Note that I would refuse additional compensation, were it offered. And the shipping isn’t much money, but it ticks me off that I am being penalized (time and money) for an issue that is his responsibility.

Let me add that the vendor is going through some rough waters, so perhaps he isn’t able to respond. I do wish him the best, and hope that this is simply the result of an oversight.