Author Topic: oil sending unit  (Read 2064 times)

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Tom H

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oil sending unit
« on: July 06, 2005, 11:27:53 AM »
Hello everyone! I have a 1976 CB 750 K6 and the oil sending unit is not working. My question is
can I get a new switch at an auto parts store or do I have to get one through a honda dealer.
                                                                                                    Thanks

Offline number13

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Re: oil sending unit
« Reply #1 on: July 06, 2005, 01:50:38 PM »
Oil sending units all pretty much LOOK the same, but are set to "go off" at
different pressures. In short, get a Honda part or your light will never go
off, or worse, not come on when needed.

word
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Offline Robert

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Re: oil sending unit
« Reply #2 on: July 06, 2005, 04:42:44 PM »
Hmm, of course many will vote for the genuine switch (and that's of course the best option apart from a full blown oil pressure gauge) but I don't know really I think it's at least discussible, the thread size of that switch is afaik called 1/8 NPT.
Switch off happens at a pretty low pressure between 2.8 - 5.6 psi (0.2-0.4 bar), most car's oil switches work in a similar range.
Regarding that oil pressure should easily reach like 80+ psi (measured at the oil pump) I'd take it one could even use a switch with a slightly differing operating range.
« Last Edit: July 06, 2005, 04:44:41 PM by Robert »

Tom H

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Re: oil sending unit
« Reply #3 on: July 07, 2005, 03:49:43 AM »
Thanks for the input guys. even though the local auto parts store has one thats looks like it could work I think I'll take Kevins advice and order one from Honda. That way if something would
happen at least I know I have the correct switch.

Offline kghost

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Re: oil sending unit
« Reply #4 on: July 07, 2005, 07:04:57 AM »
Sorry Robert,

Got to disagree, On the 750 the switch works a 7.6 psi +/- a little. The oil switch gets its pressure frome the upper crankshaft oil gallery. You really want that light to be accurate if you have no gauge.

The oil pressure on th 750 max's out at about 56 psi as the pump is regulated.
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Offline pmpski_1

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Re: oil sending unit
« Reply #5 on: July 07, 2005, 09:50:57 AM »
Hey Tom,

I recently replaced this part on my CB550. Be really careful when you tighten the bolt to attach the wire. I over tightened mine and broke the bolt. I don't know if I had the bolt threaded incorrectly or if the bolt was defective. Either way, after a bit of pressure as it was getting tighter, it broke. Be careful in case there's a batch of bad bolts out there.
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