Sending unit giving 140 ohms resitance
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Sending unit giving 140 ohms resitance
Talking about a recently bought 77 Vette Stingray. Not much info on the sending unit, possibly original, but not certain. The fuel gauge is almost always at full. I have, however, seen it show lower levels of fuel. Today I tested the resistance on the sending unit pretty much assuming it won't render anything, hence the fuel gauge always at full. (Seen it more than once on these old vehicles when the sending unit is dead and the gauge is stuck at full). But the sending unit actually shows resistance of about 140 ohms. The tank is full as I filled it up earlier today and also physically checked the level by looking inside the tank.
All the info I have been able to find online is that a C3 sending unit should range between 0 and 90 ohms (much like any other GM car of that era). Is it possible though that my sending unit ranges, perhaps, between 0 and 150? The gauge I have clearly can't handle anything over 90, and thus if there is more than half a tank of fuel, it will just show full. However, if the physical fuel level drops below about half a tank, the gauge starts going down as the resistance enters the range of what the gauge actually understands (under 90 ohms).
Has anybody seen anything like this or should I just assume my sending unit is broken if it gives this big a resistance?
All the info I have been able to find online is that a C3 sending unit should range between 0 and 90 ohms (much like any other GM car of that era). Is it possible though that my sending unit ranges, perhaps, between 0 and 150? The gauge I have clearly can't handle anything over 90, and thus if there is more than half a tank of fuel, it will just show full. However, if the physical fuel level drops below about half a tank, the gauge starts going down as the resistance enters the range of what the gauge actually understands (under 90 ohms).
Has anybody seen anything like this or should I just assume my sending unit is broken if it gives this big a resistance?
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Your resistance is indeed high. Replace that sending unit. And yes you need to drop the tank on a 77.
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From: New Or-leens Loo-z-anna
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From: Sunshine Coast, Queensland, Australia
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Non rookie answer. NO.
that would throw everything off. It's possible that the copper strip's are corroded on the rheostat and a good clean up might restore it. But dropping the tank would have to be done anyway. And pulling the tank out is not at all difficult. However, big enough job that I would have a new sending unit and some new rubber fuel line in hand before dropping the tank.
that would throw everything off. It's possible that the copper strip's are corroded on the rheostat and a good clean up might restore it. But dropping the tank would have to be done anyway. And pulling the tank out is not at all difficult. However, big enough job that I would have a new sending unit and some new rubber fuel line in hand before dropping the tank.
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