Start relay swap

[Midnight Special]

Anyone swap out the OEM 20A start relay on the fire wall to a Ford Style 80A?  How difficult(I SUCK AT ELECTRICAL)is the conversion. 

Thanks in advance

[NYrr496]

It's very simple.

[illfish]

I put the ford relay under my dash after talking to my buddy.  That way I can run all the power for fans, pumps etc right there.  You just run the battery cable to the one copper post.  On the other is the cable running to the starter itself.  The single small lug is for switched 12V.

[NYrr496]

The thing I like about it is if you hook it up like a Ford starter, the cable is only hot during cranking.

[gt]

When you do this don't forget to put a link between the battery post and the switch post on the starter, so both are hot when the solenoid is activated.

gt

[Midnight Special]

When you do this don't forget to put a link between the battery post and the switch post on the starter, so both are hot when the solenoid is activated.

gt

HUH.......EXPLAIN THIS, I SUCK AT ELECTRICAL

[NYrr496]

The positive battery cable first goes from the battery to one lug on the solenoid. The other solenoid lug goes to the battery terminal on the starter solenoid. You have to jump the pull in wire on the starter's solenoid to the battery cable lug right next to it so the starter will operate when you energize the cable.

Now, you take the wire that originally went to the starter solenoid and use it to energize the Ford solenoid. Ground the other stud. This way, when you turn the key, you connect the circuit in the ford solenoid, energizing the cable going to the starter and the starter cranks the engine because you have the starter solenoid jumped to the cable lug.

I think Painless Wiring has a diagram on their website.

[illfish]

With a ford relay and a mini starter, all you need is the ford relay.  Battery to solenoid post then other solenoid post to starter lug.  Small wire to trigger relay.

[68_Val_Sedan]

With a ford relay and a mini starter, all you need is the ford relay.  Battery to solenoid post then other solenoid post to starter lug.  Small wire to trigger relay.

you will also need to jump the small wire on the starter to the big lug on the starter or the starter will never engange ....

[oldkimmer]

...........................So will going from a 20 amp relay to a 80 amp relay give the starter more juice to crank the monster lurking under the hood,especially when hot, and r u better off to bridge the starter terminals or leave it as is?.........thanks ..........kim...........

[NYrr496]

The amp ratings on the relay are telling you what the relay is rated to carry. You won't get more juice to the starter from the same battery and cables just by adding a better solenoid. You will, however get more voltage to the starter solenoid this way because the solenoid on the starter is getting full battery voltage from the cable and the bridge. If you do this with a mini starter and use 2/0 cable and a group 24 battery with like 800 or 900 cranking amps, you will never have hot starting problems ever. I start 2300 horsepower Cat diesels like this. They crank fast and hard, only difference is I use 4/0 cable and 1300 amp 8D batteries.

[Capt Jack]

basic idea

[NYrr496]

Jack's got it.

[oldkimmer]

.................................Thanks guys................kim............