sending units (best way to run stock & aftermarket)

[dsmd58]

just curious if anyone can help me answer these two questions on a 89 350 tbi:

1 - i am looking for the location to install a new sending unit for my oil pressure gauge. i want to retain the oem gauge.

2 - also looking for a location to install a new sending unit for my water temp gauge. also want to retain oem gauge.

is there a way to run both oem and aftermarket gauges? i have already installed them into the dash, the tranny temp was a no brainer, but these two have me thinking....help

 

[dyeager535]

Stock location for oil pressure is to the drivers side of the distributor. Bell shaped piece.

Temp sender is located on the drivers side cylinder head, green wire going to it, "nail head" type connector.

Are the new guages mechanical or electrical? That will make a big difference on how you run them. I suspect if both electrical you could just split the wiring right at the connector, while if mechanical you'd need some sort of t fitting or something.

 

[dsmd58]

they are all electrical. i bought the autometer gauges based on the board's input. installed them into the center of dash above the vent.

so you do think it should work if i just splice? do you know the color of wire on the oil sender? i think i read one of your posts, it should only have one wire right?

 

[dyeager535]

'89 should have a one wire oil pressure sender, yes. Believe it's tan. There will be a two wire switch for oil pressure somewhere on the motor, but ignore that, it's for the fuel pump relay. I don't know where GM put that switch, likely same place as the pressure sender or above the oil filter.

As long as you don't overload the wiring for the sender I don't think splicing will be an issue, and I doubt it will be if you keep the wiring separate for most of the run, connecting them as close to the sender connector as possible. The oil pressure one will be difficult to make look "clean" as the connector is likely a snap-on rubber cup. Mine is, but my truck wiring is a bit earlier than yours. I really don't like splicing if I don't have to, it adds failure points to your wiring. Both via possible corrosion and breakage.

For engine temp you could use another sender on the passenger side head (same general location as the OEM location on the drivers side, but further back) or if it were me, I'd de-pin the connector and solder or crimp your new wire to the factory connector.

 

[dsmd58]

thanks for the info, but do you think it will be a prob with stock senders and autometer gauges?

 

[blazin_blazer]

i would put a oil sending unit by the oil filter, then you would know your pressure on the bottom end and your stocker tell you your pressure up top, that way if sending unit goes bad both gauges don't quit

i'd put my water temp in manifold under the thermostate if theres a place for it(maybe get housing to fit it), then you have water temp where its leaving the motor..where it should be hottest, if not there, deff other side in the head, then whole motor is pretty much under watch

 

[badmix]

Your autometer gauges WONT work off of OEM sending units, not sure where some ppl got that idea and IF they got it to work, I wonder how accurate it is.

Im running OEM volt, oil press. and water temp.

But im also running auto meter gauges as well, im running oil press. water temp, volt meter and tranny temp.

For Water temp, I had spot on the intake manifold that had a plug in it, pulled the plug and put the sending unit there.

For oil pressure, I had to T off of the sending unit down on the block by the oil filter. I disco'd the wire going to the OEM one down there and got a check engine light, not sure what that was all about, so I left connected and just T'd off of it, its not pretty and im not 100% happy with it, but its been that way for couple years and never gave me issue.

 

[GNERGY]

This is how I did mine on a 91 Burb 383 motor to run a Summit digital oil pressure gauge.
I drilled and tapped another hole in the stock fitting.
Tarey

 

[lectric80]

There is no guarantee that the stock sending units and the Autometer units are going to be using the same resistance numbers. The only guage from Autometer that is designed to work with stock sending units is the fuel level gauges, this is why they provide the senders. GNERGY's suggestion is probably the best way to do it, but you should keep in mind that those types of fittings need to be checked for leaks periodically.

 

[dyeager535]

Well damn, if the autometers don't measure the same way, my ideas are out. Unfortunately I assumed using stock sending units would be the smart way to do business. Or maybe not if you want to force people to buy more of your products.

 

[UPS]

The sending units come with the gauges. The Autometer sending units are more accurate than stock ones are.

Mike

 

[lectric80]

In my case I didn't want the stock sending units, as I was removing the gauges from the dash. But, I am not saying it won't work, I am just saying that it is entirely possible for them to use different ranges. And, as UPS said, the Autometer sending units should be far more accurate than stock.

 

[diggy]

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[CGT80]

I have heard that there is an oil pres port on the front of the block, top, near center. I have an 1/8" plug there on my 79 pickup 385 cu in engine, but I have not removed it to see if it would work. I also have an 88 350 K5 but i have not looked on that engine.