What are these two?

[win32exe]

what are these two electrical items on the fender wall? i know the starter relay, but what are the other two square relays?

[win32exe]

i think i figured out that the larger of the two is the horn relay, can someone confirm, maybe ill just go pull it and see if the horn stops working, but what is the smaller one and also what is this sensor on top of the intake manifold?

[amcfool1]

hi, yes the large one is the horn relay. The small one is, I think, the relay for the manifold preheater, not 100% sure on that. On the manifold, thats the knock sensor. If your CeC system is working, its important to have. good luck,  gz

[win32exe]

thank you, i swapped out my carb and distro, no computer anymore.

thx again

henry

[win32exe]

a little info on this subject please, i want to swap out my oil pressure light for a mechanical oil pressure gauge, where is the best place to get oil pressure from?

is the wire\sensor on the rear of the cyl head the idiot light? is that where i should get my oil pressure from?

what is the ?sensor? near the starter? is that the oil pressure switch?

also does the intake preheater system need the computer (ecm) to work? or just the relay and wiring to the manifold? how can i test that system for functionality? i removed my computer.

Thank you

[Illeagle1984]

I'll try to answer the questions in order.

The best place to get oil pressure from is the OE oil pressure sensor port.

The sensor on the rear of the cylinder head is not the sensor you seek.  There is no oil pressure in the cylinder head.

The sensor near the starter is the oil pressure switch.  It is wired to the electric choke so that a key-on, engine-off event doesn't cause the choke to open with the engine still cold.  I think the best bet would be to find a T adapter to leave the OE switch in place, but still be able to plumb in a second sensor.

The manifold heater is also driven off the oil pressure switch, again so it is not continuously running with key-on, engine-off.  If you want to know if it's working, just start the engine and try to feel that round thing on the bottom of the intake under the carb.  It should begin to feel warm after about 3 minutes, long before the metal of the intake gets warm.  Easier to tell when it's cold out.

[djm3452004]

The best place to get oil pressure from is the OE oil pressure sensor port.

As stated above, just tee off of the female 1/8" NPT oil-pressure port in the block, and this way you can keep the standard oil-pressure switch and run a line to a dash or console oil-pressure gauge.  All the fittings you would use will be 1/8" NPT as pictured on my block.  The fittings to adapt to an aftermarket oil pressure gauge will be included in the gauge's kit.

Hope this helps --
David