WagnMastr

I have an Olds 455 that I need to hook my gauges to the sensors on the block.
I see 4 sensors (for lack of correct terms).
1 - just above and to the right of center (facing front to rear) of the water pump (single prong).
2 - just above that higher up on the intake manifold (single prong).
3 - just behind oil filler tube - two prongs with vac hose to carb.
4 - rear back on heater hose outlet where there is a vacuum diaphragm.

Sorry for the purists out there, but this is now in a 1973 International Harvester Wagonmaster. Please find it in your heart to help me!

2blu442

Breath new life into that cornbinder!

1) is for the oil pressure

2) is for the water temp

3) you can probably ignore, one of the other guys can explain it better than I

4) this has to do with the valve opening for hot water to enter the heater core. Some applications just have a pipe fitting threaded into the intake manifold that's always open, which would be the simplest thing here too.

There's a starting point. I'm sure others will chime in with more information.
John

svnt442

The connector on the vacuum port is for the TCS.

The vacuum port on the diaphram needs to be hooked up or the heater control valve will not work.

Bluevista

Welcome. Too cool, don't see those every day, or year.
Didn't Lassie's national park ranger dad have one of those?


The water valve is for air conditioning, closes off the flow to the core when you set it to high cool.
If the other other thing has one vac line to the top and three fittings on the side it's the distributor vacuum switch, don't need it. I just faked mine out for appearance with some hoses and T fittings, all go right back into it.
Connected the lines to ported vac for the distributor advance and manifold vac for the trans modulator.

Jamesbo

Welcome aboard

Looks like Blue and Randy got ya figgered out.

WagnMastr

Thanks for the quick responses. Now to see if my original gauges will work with them. The 455 runs great in there. I need to do something with the linkage to the tranny as the column shifter won't go to 1st. It needs all the HP and torque for this 5K pound beast. Can't imagine what the 350 diesel would have done in it. Originally, it had an IH 392.

svnt442

If you have actual gauges you'll need to correct sending units as the one's for "idiot lights" are just glorified on-off switches.

Oldsguy

Welcome to CO. That is a really nice looking truck, that is a cool color.

joe_padavano

Are you trying to use the original IH gauges? In that case, you'll probably want to install the IH senders that match them. There's no guarantee that the Olds senders have the same resistances as the IH senders. Again, you ARE trying to use gauge senders for the gauges and not the idiot light senders, correct?

WagnMastr

Yeah, I am trying to use the stock gauges. Hopefully, the thread pattern for the two sending units/sensors will be the same. I didn't know there were different types-ones for idiot lights (which I must presume were what was in the '71 Olds 98 that I yanked the engine/tranny from), and ones that would go to real gauges. NAPA should have the ones I need.
Thanks for all your input guys. I'll let you know how it turns out.

joe_padavano

The oil pressure sender is easy. These are typically NPT and it's perfectly acceptable to screw together whatever adapters you need to get pressure to the sender. The temp sender, on the other hand, needs to be in the flow of coolant, which is usually in the coolant crossover on the front of the intake. Again, these are typically NPT. If the IH sender is smaller than the threads in the Olds manifold, it's acceptable to use a bushing, so long as the tip of the sender is still in the flow. If the IH sender is larger, you'll either need to find a new sender or get one of the aftermarket pipe sections that go in the upper radiator hose and have a threaded bung for the sender.

WagnMastr

That's good to know, Joe. Both will be at NAPA for me to pick up tomorrow. OIl pressure appears to be same thread, but will need to use a bushing for temp. The IH one is smaller and I will line them up to see if it will get into the flow when screwed in. I wouldn't have thought of that, so I appreciate it. The IH one's tip appears to be longer than the other, so I am keeping my fingers crossed.
This old truck was sitting out in a farmer's field for 15 years up until Nov last year. Getting these two gauges rolling are the last things I wanted to do before giving it a highway test. So, I am excited and thank you all for your advice.