Alfa Romeo Forums banner

1 - 10 of 10 Posts

·
Premium Member
Joined
·
2,160 Posts
Discussion Starter #1
Hey all,

I'm helping a friend put together a track car, which is a '67 Super. It's been gutted, and we're wiring it from scratch. The components are an aftermarket fuse box, dash and gauges from the Super, and everything else from a mid 70's Spica injected car.

It's been a learning experience, but we've gotten everything working, with a couple of quirks.

We're having trouble with the oil pressure gauge and the fuel gauge. (As an aside, the temperature gauge appears to work perfectly, and the low fuel light does too).

The behavior we're seeing with the oil pressure gauge is that it never reads anything. If we take the wire off the sender and short it to the block, the gauge pegs. If we take some resistance measurements from the oil pressure sender while the engine is running, we can see the resistance values go up and down.

So, the question is, *should* an oil pressure sender from a mid 70's Spica injected Alfa work in a '67 Super? If not, will a Super oil pressure sender screw in to the same place on the block?

Wrt the fuel gauge, we're seeing something similar. First, we do have the leads for the gauge and the warning light on the proper terminals. When we short the gauge to ground, it pegs. When we connect it to the terminal, it pegs. When we pull the sender from the tank and measure resistance between the terminal and ground, with the float in the 'empty' position, we read 39 ohms. I can't remember what it was in the 'full' position, I think around 1k ohms.

Same question on the fuel system. *Should* the fuel sender from a mid 70's Spica Alfa work with the fuel gauge from a '67 Super? If not, which sender would fit in a 12 gallon (I think) tank, and work with the Super.

For any real electronic geeks out there, I'm assuming that a combination of resistors in conjunction with the senders/gauges could also make things work. Anybody BTDT, and have a diagram with values?

Thanks,

bs
 

·
Registered
Joined
·
2,578 Posts
I found I could not mix the gauge and sending units. I had 0 oil pressure when the gauge was Jaeger and the sending unit was V***** (I can't remember how to spell it )
 

·
Premium Member
Joined
·
757 Posts
That is also my understanding. You cannot mix sending units and guages. So you would have to replace either the sender or the gauge. I'm not sure if the older sender will screw into the newer block.
 

·
Premium Member
Joined
·
2,160 Posts
Discussion Starter #4
That is also my understanding. You cannot mix sending units and guages. So you would have to replace either the sender or the gauge. I'm not sure if the older sender will screw into the newer block.
I'm starting to get the impression that you can't mix gauges. And yet the temperature gauge works perfectly!

Does anybody have a Super with a proper sender/gauge in it, that could take some measurements for me? I'd love to know what's coming off the sender..

bs
 

·
Premium Member
Joined
·
21,463 Posts
Heck, just keep trying them til you get a reading you like. Oil pressure read low? Swap senders til you get a good reading.

Truthfully, my experience agrees with the above comments.

Andrew
 

·
Premium Member
Joined
·
2,160 Posts
Discussion Starter #6
Heck, just keep trying them til you get a reading you like. Oil pressure read low? Swap senders til you get a good reading.

Truthfully, my experience agrees with the above comments.
Well, that would be a great plan, if we had a wide variety of senders to swap in and out! Unfortunately, we don't, but we will swap everything we've got.

On the other hand, if somebody could tell us what the actual Super gauges were doing, then we could determine if some resisters in and around the senders we've got could change their behavior to what we're looking for.

So, anybody game? Need to know the resistance of a Super oil pressure sender at idle, then at some RPM's. Also need to know the resistance of the fuel sender empty, and then full.

One of the problems with just going out and buying new super stuff is we don't know if it will fit into the 2 liter block and gas tank that we're using.

Thanks for the input so far!

bs
 

·
Premium Member
Joined
·
2,160 Posts
Discussion Starter #8
I have a few spare fuel sending units. I just need to know which one you need. So, if there is something I can measure to find the right one, let me know. As for the oil pressure sending units, there is an early type and a late type. The late type won't work with the early gauges and vice versa.
That would be great!

If you have early sending units for the oil pressure and fuel, we'll borrow them and return them (or buy them if you'lre looking to sell?). We'd want the ones that came with the 1600 engine in the Super.

I can't tell you what to measure to find the right fuel sender, because we don't know! If there's a visible part number on them, we might be able to look it up.

I'll PM you with contact info..

Thanks,

bs
 

·
Premium Member
Joined
·
2,160 Posts
Discussion Starter #9
I'm back with a little update. Thanks to those who offered help, this has been on and off the back burner for me, as we struggle to get the car in shape for the convention, and as I put time into my own car for the convention..

At any rate, I have an update. Based on a tip from Dave Pratt, I measured up the fuel tank sender from a GTV. It's got a similar 'in gauge' fuel gauge to the Super, which is different from the standalone fuel gauges from the Spider and Berlina. Lo and behold, the GTV sender had resistance readings opposite to what the Spider read, so we installed it in the Super and it works fine! Had to bend the arm a little bit, as the GTV tank and the Super tank have slightly different capacities and depths, but as of now, that problem is solved.

So, one for the archives!

bs
 

·
Registered
Joined
·
3,728 Posts
Well, that would be a great plan, if we had a wide variety of senders to swap in and out! Unfortunately, we don't, but we will swap everything we've got.

On the other hand, if somebody could tell us what the actual Super gauges were doing, then we could determine if some resisters in and around the senders we've got could change their behavior to what we're looking for.

So, anybody game? Need to know the resistance of a Super oil pressure sender at idle, then at some RPM's. Also need to know the resistance of the fuel sender empty, and then full.

One of the problems with just going out and buying new super stuff is we don't know if it will fit into the 2 liter block and gas tank that we're using.

Thanks for the input so far!

bs
This is probably way too late for Brian, but I never saw an answer to some of his questions.

I have been with out an oil pressure gauge in my Super for a couple of years now. It is a 1970 Canadian Spec (1600) with Alfetta 2 litre in it.

The Veglia gauge (Pictured) quit and was found to have an open circuit on one of its internal coils. I actually took it apart to look after measuring open circuit with an ohm meter.

After some looking I bought a NOS Veglia gauge that looked the same on the front and almost the same on the rear.

The gauge resistance readings where as follows COM to Ground 255 ohms;
+ to ground 306 ohms; com to + 52 ohms.

The Veglia sender that I used read 11.0 ohms when engine off and 50-55 ohms when running. It was marked 64.5024, 0/8, 12V. Another similarly marked sender that I did not test read 48.0 ohm engine not running.

But it is not that simple, another gauge I have that has ohmeric readings about the same as my gauge does not work and other Veglia sending units that look the same but with different markings either are defective or are some how different. They give a quick ohm reading them go open unless I measure with what I think is a diode tester. I had a very frustrating afternoon finding and trying sending units, checking wiring wondering if my new gauge worked.

So maybe you can't mix Veglia parts and I think it is also clear that you can't mix Veglia and Jaeger parts although they may look similar.

FWIW

Ken
 

Attachments

1 - 10 of 10 Posts
Top