MAJOR Tune-Up questions for a neglected Farm Truck

[frogman68]

Thanks Blazin!

The oil pressure sending unit is indeed electrical looking at the part. It threads into the engine and then it looks like a single wire will clamp onto the top of the unit. I'm still at a loss as to how to change out the old unit for the new one. I don't see how you can work in that small a space

I might just do the distributor my self as well. Do I need to take the hole distributor of or just unplug all the wires, mark which wire it is and where the go on the cap. Take the cap off, take the rotor out. Put the new rotor in and new cap and attach all the wires? If that's all it is, I can do it, but IF I need to reset the timing, mess with setting the No. 1 Cyl @ TDC, I'm at a loss.

While I'm at the distributor, it's probably easy to put the new oil pressure sending unit in as well.

get a stubby 9/16 (think that is the size or its 5/8) and come from the carb side towards it.

[Blazin]

The oil pressure sending unit isn't to hard. I have done them with a pair of channel lock pliers before. They are not super tight. As far as the cap replacement you don't change the timing at all. I usually take the old cap off with plug wires still attached. Leave it laying right there, then replace the wires with the new ones onto the new cap in the same order. The firing order should be on top of the intake, and number 1 should be toward the car on the right front corner of the cap.

[1980c10]

plugs and wires are best done one at a time as to not get them mixed up. Get yourself a set that is made to fit(not universal) if you are looking to keep it simple. I 2nd what blazin says on the cap; just remove it with the wires attached. you will see just how easy it is to change the rotor when u get the cap off then change the wires with the new cap in place. have funwith it and if u get jammed up; just jump on here.

[Irish_Alley]

you could take the dis out to mess with the sensor, me personly would do the who works. but you can take the cap off and do one wire at a time then change the rotor in case you get mixed up the firing order will be 1-8-4-3-6-5-7-2 your right(from inside the truck) side cylinders are | 2 4 6 8 | of | | your left side are(from inside the truck)  | 1 3 5 7 | Distributor rotates clockwise number one wire should be pointing to number one piston.
if you take out the dis. make sure you remember which way the rotor is pointing it can only go in two ways the way you see it and 180 degrees out so as long at you get it close and watch the rotor as you pull the dis. out it will move slightly from the cam shaft

[1980c10]

Good point on the rotor, however, If u do remove the dist. make sure u mark the dist and engine block as it can be put back in slightly off. I bought an 82 that the distributor had been put in one spline off and run that way for 8 years before I got it. when i couldn't use a timing light to time it; I figured it out and it made a world of difference to put it in properly.

[VileZambonie]

In operation, it will recuce some NOx by injecting compressed air downstream of the combustion process to help burn off by-products.

AIR doesn't help NOx reduction, just HC and CO emission levels.

[HookedOnReefing]

Well, got the oil pressure sending unit out and put the new one in. What a pain to get to! But it's done and the oil pressure gauge is once again indicating something rather than just dancing across the dial

I've never had this truck with working gauges so have no real base as far as oil pressure and coolant temp is concerned. Oil pressure is consistently 15 PSI and it doesn't really matter weather it is running at idle or being driven. Coolant temperature runs consistently at 150*F. Are these acceptable/normal numbers?

I've not yet replaced the distributor cap and rotor as well as plugs and cables. But will play with it this week. You guy's have given me the confidence to do the job. If I screw up, I've got more trucks that I can drive while fixing this thing and will ask you for help

I have been replacing some of the vacuum hoses. They're in bad shape. I've replaced the easy ones. Some of these seem to come together into some sort of "plug" that plugs into a "connector with pins". It kind of looks like a trailer pin connector to power your trailer lights/brakes etc. (Is this part of the TVS???) Rather than going ahead and pulling the hoses off, I thought I ask you guy's first. Can I pull out the hoses and put new hoses in place of the old vacuum hoses OR does the hole connector/plug need changed out???

The other question I have is regarding the Thermostatic Air Cleaner Motor. On the bottom of the air-snorkle, there is a hole (shut by the damper door). Below that on the exhaust manifold there is also a hole. Shouldn't there be something there that connects the 2 so that it can pull in warm air when needed like a hose or pipe?

What are some of the tell-tale signs that you have a vacuum leak? How does it affect the engine/performance?

[1980c10]

15 psi is fine for idle, however it should increase as the rpms increase. With a consistant 15lbs I would question the accuracy of the guage it should be higher when u 1st start the engine. 150 degrees is a bit cool but again your guage may not be real accurate. I would mainly watch the guages and worry if u drop oil pressure fromwhere u r at. and keep an eye on the coolant temp to make sure your are not getting too hot. For the vacuum hoses u can just replace the hoses. there should be a tube aprrox. 2" in diameter that connects the exhaust manifold to the air cleaner housing to pull in warm air for cold weather if this is not there I would not hookup the vacuum line to run the damper door. Their also should be a vacuum diagram under the hood in front of the engine on top of the radiator area on the header panel. this will show u where the vacuum lines go alsomake sure that they are routed correctly.