2.7 Engine Swap Help!

[combatic]

Hi all . I have an oil pressure gauge that pegs out under normal driving rpms (I think it jumps up at around 2K on the tach)

I have swapped a 1977 2.7 into my 1969 chassis (69 gauges as well).

I have the sending wire attached to the sensor on the aft portion of the motor just to the right of the fan (see picture below)

I suspect the 1977 pressure sending unit has too high of a resistance drop than the 69. I bought a sending unit for the 1969 m.y. but of course it does not fit (threaded end is several mm too small.


Options that I have thought of-

-Have an adapter machined to fit the 1969 sending unit to the 1977 block = $$$ + easy to install

-Find a 1977 pressure guage (if it fits), have N. Hollywood or similar 'backdate' it to 1969 look (but then I should do ALL the guages to look right =$$$$ + time + PITA to install.

-Find some smart cookie on Pelican to tell me what the resistance range of a 1969 pressure sending unit is vs. a 1977 unit AND then I can ask an EE here at work what resistor I need to put in line to bring the Ohms up to 1969 levels = $ + easy peasy to install. <-- I suspect that the 1969 sending unit has a higher resistance than the '77 unit and I assume that the way the sending unit works is that it resistance drops as pressure increases sending higher voltage to the gauge and electrically moves the needle up.

Thoughts 2.7 swap gurus? What have you guys done in this situation??



Here is a pic of my current Weber removal for rebuild project (b/c we all like pix in threads =)

[KevinS]

Sorry dude can't help you, but will give you a bump to the top. I'm sure someone here has dealt with your issue.

[combatic]

Thanks for the bump Kevin.

[Bill Jennings]

I was told by a instrument tech here in Australia that an old school auto electrician could test my temp gauge for the resistance range it responds to. I have a 77 for which there are two different part numbers for the senders and they each have a different resistance.
In the end my problem was fixed by replacing the gauge then trying both senders to see which one worked.

Cheers

Bill

[jpnovak]

Brian,

Find a 2.7 gauge. remove the oil pressure unit from the back using the 2 screws. Install into your 69 gauge. problem solved.

This is the easiest way. Just swap the internal gauge pod between the gauges.