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Replacing the starter solenoid

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M

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I know, in theory, how to replace a starter solenoid, but is there anything special to know when replacing a starter solenoid in a TR3? I find that these cars always have special conditions or quirks that make them different from many other cars.

Here are the steps I know about:

1. Detach ground from battery

2. Loosen bolts on solenoid

3. Remove wires from solenoid

4. Remove solenoid

5. Install new solenoid

6. Reattach wires to solenoid

7. Reattach ground from battery
 
Works for me, provided step 2. is removing the nuts that hold the wires to the solenoid. I would do that before removing the screws that hold the solenoid to the body.

Note that the nuts for the heavy cables to the solenoid are a funny size, 3/16" Whitworth (which is actually about .445"). If you don't have a suitable Whitworth tool, you'll probably want to use a small adjustable wrench or similar.
 
Just be careful of the hardware. I believe the original solenoids have BSF (British Standard Fine) threads, which are different then the UNC/UNF stuff we are used to. If your new solenoid has hardware, it won't be a problem. Just realize, that there might be a difference between the old and the new.

Edit: BTW, after two bad solenoids from Moss, I finally used a Ford unit that cost me a whopping $8 from the local NAPA guy.
 
In a recent discussion I think we concluded that the rubber button points rearward.

Even if you discard the old solenoid, save the big nuts from it -- you just never know.

Good opportunity to clean all connections.

Rmember that the solenoid needs to be grounded to work and that ground comes from its attachment to the body (2 bolts) so those need to be in place & tight for it to be tested.

When testing the push button be double-sure the gearbox is in neutral -- I'm sure that <span style="font-weight: bold">I</span> have never run over my foot trying to bump the engine with that button.
 
Geo Hahn said:
When testing the push button be double-sure the gearbox is in neutral -- I'm sure that <span style="font-weight: bold">I</span> have never run over my foot trying to bump the engine with that button.
Click to expand...
:lol:
George sez, "Don't ask me how I know that."
 
Here is the original one that is still on my 1958 TR3A.
 

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This is a parallel question for those of you running the round, pushbutton solenoids.

Several of my British cars have had these from new. However, the replacement units I have bought have all failed relatively quickly. (At last count, I've gone through 4 of them with the longest lasting one surviving only about a year).

Do you guys have a source for good, high-quality, pushbutton, round solenoids?
 
Thanks for all the good information and guidance. There is nothing wrong with the original solenoid in my car, but I am in the process of replacing every component. This car has lasted 50 years and I want it to last another 50 years (for my kids and grandkids). However, from what I read here, I'm probably better off sticking with the old solenoid until something goes wrong with it rather than taking a chance on a defective new one. This is one component I believe I will keep, for the time being.

I've had pretty good luck with other replacment components, except for the voltage regulator (we went through 3 new ones before we found one that worked!).

BTW. I know that I am challenging the old saying: "If it ain't broke, don't fix it."
 
Good thinking Ed, if it aint broke etc,etc...............

Tinkerman
 
LexTR3 said:
I know that I am challenging the old saying: "If it ain't broke, don't fix it."
Click to expand...
Once one gets past all the tired Lucas jokes, the sad fact seems to be that currently available "repro" (even if branded as Lucas) electrical equipment is just nowhere near as good as the originals. Some old axioms are better left unchallenged; "If it ain't broke..." is one of them, IMO!
grin.gif
 
dklawson said:
...Do you guys have a source for good, high-quality, pushbutton, round solenoids?
Click to expand...

I obtained a good (perhaps new) old one on eBay. As I recall these were not marked with date of manufacture (or even a Lucas mark) but perhaps there is some other way to tell an old one from a modern?
 
The body on my original starter solenoid is made of a casting of white metal or possibly cast aluminium with a thick heavy look to the wall or barrel part as well as the "feet". I believe the newer repro ones have the barrel made out of pressed sheet-steel which is then white zinc plated. The repros might have a push button whick is covered with a domed black rubber "seal" but some repro units come without the rear button to start the engine from the engine compartment.

The sheet-metal repro units have the feet where it is secured to the firewall about 1/16" thick whereas my original one has cast feet almost 1/4" high.
 

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I'm convinced... I'm sticking with my old "original" solenoid.
 
dklawson said:
Do you guys have a source for good, high-quality, pushbutton, round solenoids?
Click to expand...
I have not tried one myself (still using the original, with some help from a gear drive starter), but generally TRF sells the best product available.

However, they do only have the later style with the sheet metal 'feet'. Lucas changed styles around 1960, and I've never seen reproductions of the early "pot metal" ones.
 
TR3driver said:
However, they do only have the later style with the sheet metal 'feet'. Lucas changed styles around 1960, and I've never seen reproductions of the early "pot metal" ones.
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Ha, you just beat me to every aspect of that comment! I've not seen a repro of the older style, either. IIRC, the rubber button/cover is slightly different between the two styles, and I don't remember if there's an available repro of the earlier rubber button.
 
Gotta say, I purchased a new push button solenoid because my car came with a ford started switch and I wanted a bit more originality. Long story short, when I pushed the button, it sticks and cranks until I pulled off the battery cable. That was a fast jig!

So I learned not to push the button after a couple of similar attempts. My solution was to purchase a nice original cast body solenoid (on eBay) as Don described, along with a new rubber switch button cover.
 
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