My 73 Series 3 Project

[lumpydog]

I was wondering if it is relatively safe to remove the old sender without draining the tank? According to the part number and what is available...it is the right one. Granted...does not ensure it will work. But I do not want to point a finger at a new part till I extinguish all other options.

It's safe. Just work in a ventilated space. No spark or flame sources nearby. If you're really concerned, a good safety measure whenever you mess with electric on your truck - disconnect the negative/ground wire from the battery.

[lumpydog]

Just wanted to take a moment and say thanks to all of you guys that respond to my posts. It has helped me a ton on getting passed one problem and on to the next. Between this forum, the green bible, and YouTube...I am getting there. I am learning so much mechanical stuff and the farther I get, the more comfortable I feel since if something does go wrong down the road (and I am sure it will)...I will be better prepared to troubleshoot and solve it.

Cheers!

Somewhere in my post history is the same post :-)

These trucks are great teachers. They are tolerant of mistakes but are also very vocal if you know how to listen (heat at the hubs). You're well on your way. Keep at it - it's a really fun hobby.

[SafeAirOne]

I use this one. At that price, nice to own/have.

Yeah, for Rover stuff/occasional use, the magnetic base dial & indicator that Harbor Freight sells is just fine too.

[ninescorpions]

Bouncing back to the hubs. I got the LF hub off today. Races were not loose in the hub and seal is ok. However the rollers on the bearings have little to no rotation. As well you can see groves worn into the rollers and race where the bearing has "locked" in place. I would assume the load of the wheel, etc has induced that wear since it is not properly spinning. I believe it was likely spinning some, but would catch on the grooves created by the roller. Take a look at the inside of the race (I believe this is outer).

I would assume this is not normal wear and tear.

[ninescorpions]

Here is what the bearing looks like (grease has been removed...so all that you see if the actual bearing).

[ninescorpions]

So pretty clear the bearings need replacing along with the races. The question I am having now is related to the hub. In the below picture, you can see where the race mounts...there is a pretty good score mark that can be felt with a finger. However is it the case since the races are tight in the hub (it took the expected amount of ground and pound with a punch to get both races out, that the hub is still ok? Really not excited about replacing hubs, but for sure races and bearings are needed.

The RF hub would get warm, but not as hot as the LF. I have to assume the same condition is present (meaning the bearing is starting to give up), but just not as far along as the LF. Either way, I am going to do the whole axle.

[ninescorpions]

Fuel Update: I also just spent some time playing with the fuel sender. I pulled the new sender and then measured the gauge connector to sender chassis (metal plate). Readings are as follows:

Actual fuel in tank: ~1/4 tank

Original sender
Fuel Reading on dash gauge: 1/32 of a tank (touching the top of "E")
Resistance range on sender (out of tank): ~19 Ohms to 289 Ohms

New sender
Fuel Reading on dash gauge: 1/8 of a tank
Resistance range on sender (out of tank): ~17 Ohms to 309 Ohms
Low Fuel range: Open resistance -> 0 Ohms when float is low enough (working fine)

Conclusion: I cannot say there is something wrong with the new sender yet and the old one seems to be working properly. I saw this truck register the right fuel level twice and that was when I first got it running. The current variable remains the new gas tank (grounding mechanism). I will try again to run a new ground to the battery for both the new sender and old and repeat the test. If that does not work, then I have to head towards the voltage regulator. I see that my water temp gauge is in the "cold" bar even when the engine is warm. Lumpydog, you mentioned that they are wired to the same regulator.

Where does your temp gauge sit when the motor is warm with a 74 C thermostat?

[lumpydog]

So pretty clear the bearings need replacing along with the races. The question I am having now is related to the hub. In the below picture, you can see where the race mounts...there is a pretty good score mark that can be felt with a finger. However is it the case since the races are tight in the hub (it took the expected amount of ground and pound with a punch to get both races out, that the hub is still ok? Really not excited about replacing hubs, but for sure races and bearings are needed.

The RF hub would get warm, but not as hot as the LF. I have to assume the same condition is present (meaning the bearing is starting to give up), but just not as far along as the LF. Either way, I am going to do the whole axle.

Damn nice detective work. You are spot on, based on what I see. New races and bearings (they are delivered paired) will clear this issue right up. Pack the new bearings in some good grease. As Mark pointed out, take the right care not to over-tighten the hub nuts - use a dial gauge.

Don't worry about the wear under the races - as long as the races are seated properly, that won't matter. Freezing the races before you drift them in will help. Def do both sides of the axle.

Dial gauge in action. Very easy to use and measure end-float with:

[lumpydog]

Fuel Update: I also just spent some time playing with the fuel sender. I pulled the new sender and then measured the gauge connector to sender chassis (metal plate). Readings are as follows:

Actual fuel in tank: ~1/4 tank

Original sender
Fuel Reading on dash gauge: 1/32 of a tank (touching the top of "E")
Resistance range on sender (out of tank): ~19 Ohms to 289 Ohms

New sender
Fuel Reading on dash gauge: 1/8 of a tank
Resistance range on sender (out of tank): ~17 Ohms to 309 Ohms
Low Fuel range: Open resistance -> 0 Ohms when float is low enough (working fine)

Conclusion: I cannot say there is something wrong with the new sender yet and the old one seems to be working properly. I saw this truck register the right fuel level twice and that was when I first got it running. The current variable remains the new gas tank (grounding mechanism). I will try again to run a new ground to the battery for both the new sender and old and repeat the test. If that does not work, then I have to head towards the voltage regulator. I see that my water temp gauge is in the "cold" bar even when the engine is warm. Lumpydog, you mentioned that they are wired to the same regulator.

Where does your temp gauge sit when the motor is warm with a 74 C thermostat?

Ok - given your temp gauge is also off, I'd shift focus to the voltage stabilizer (not voltage regulator - that's different) - stabilizers are prone to failure. It's a small device that is mounted to the back of the speedo. It shifts the voltage to 10V down from 12V. Basically it has two inputs marked "B" (I think referring to battery) and two outputs marked "I" (I think for instruments). In any case - the B terminals are for the 12V power source - dark green. And the "I" terminals are the 10V output to the temp and fuel gauges - light green. Pretty simple.

The way these are typically setup on a Series 3 - one 12V dark green into "B" and one 10V light green from "I" out to the fuel gauge and jumped over to the temp gauge. You can get an "analog" voltage stabilizer but I find the Moss motors "solid state" ones (you want negative) to be better, in that they deliver a rock solid 10 volts - no ifs ands or buts. Buy a few of them to have a spare. My money is on this solution to get your temp and fuel gauges back in the game.

My temp gauge (82 deg Celcius) reads dead middle at operating temp - the needle sits right on the "N".

[cnfowler]

How to use the dial gauge to set end float.

https://youtu.be/bn3ADa06MZI


Colin