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My question is this. I was reading where it is possible to upgrade to a newer, smaller, square, four prong relay; and get rid of the giant, round relay.
I do not want to use any sort of "modified" wiring from stock. Simply replace the relay with a modern one.
Can anyone recommend a suitable replacement capable of handling the volts/amps, and a wiring diagram for such a replacement?
There's a bit more to it than just throwing the Bosch type relay at it but nothing complicated.
You first need to ensure the solenoid has an external "small wire" and disconnect it. And, the 2 big cables on the round relay have to either be jumped or a new cable run from the battery straight to the long post on the solenoid.
You'll have to "move" a couple small wires. Depends whether you want to leave the original in place, as to how you go about that.
I wired my '74-74" to a Bosch relay. without incident nor Concern... been that way for literally Years!!!
Only one lone XLH still sports that old Ford relay!! Just because I'm lazy and Have not even switched it to a more reasonable Battery either!!!
There's a bit more to it than just throwing the Bosch type relay at it but nothing complicated.
You first need to ensure the solenoid has an external "small wire" and disconnect it. And, the 2 big cables on the round relay have to either be jumped or a new cable run from the battery straight to the long post on the solenoid.
You'll have to "move" a couple small wires. Depends whether you want to leave the original in place, as to how you go about that.
Otherwise, the pin out in post #2 is correct.
Not sure, someone can comment,
I believe this wiring scheme is for the bypass that causes solenoid run on. I just want to replace the round relay with a new model.
"The" difference is - your original arrangement has the main battery cable running thru that big round relay. And, the solenoid is another relay unto itself. That leaves 2 places for a voltage drop and that drop to the starter motor is the very cause of starter run-on, 95% of the time.
My wiring "scheme" (and I take no offense) is precisely how Evos are wired from '84 thru '88 and they use the identical starter motor and solenoid, fork, bendix, etc. Starter run-on with an Evo is basically unheard of.
Maybe we misunderstood, but you're not gonna find a simple 4 pin relay to carry the amperage that motor draws. It takes 30 amps to run one on the bench and will pull upwards of 200 amps turning over the engine. The solenoid is perfectly capable of that, but anything besides a massive relay will not feed the solenoid and motor.
Like I said, you can wire it with the small relay and leave what you have in place just for looks, but it takes some small changes to the connections which I'd be glad to explain when I have more time. Or do away with it altogether and wire it like an early Evo. Otherwise, here are your only 2 choices:
I converted my Kick only shovel to electric start by using the CANNONBALL Stealth Starter as supplied by W&W in Germany, great bit of kit and in it you get a real nice starter relay, small, handles 300cca+ and is simple to fit and use, I am sure it can be used on a standard shovel type starter, from what I gather, it is the same unit as used on Ducati's, worth looking at if your looking to upgrade from a 60 year old generic Ford item. W&W Cycles - Starter relay (wwag.com)
"The" difference is - your original arrangement has the main battery cable running thru that big round relay. And, the solenoid is another relay unto itself. That leaves 2 places for a voltage drop and that drop to the starter motor is the very cause of starter run-on, 95% of the time.
My wiring "scheme" (and I take no offense) is precisely how Evos are wired from '84 thru '88 and they use the identical starter motor and solenoid, fork, bendix, etc. Starter run-on with an Evo is basically unheard of.
Maybe we misunderstood, but you're not gonna find a simple 4 pin relay to carry the amperage that motor draws. It takes 30 amps to run one on the bench and will pull upwards of 200 amps turning over the engine. The solenoid is perfectly capable of that, but anything besides a massive relay will not feed the solenoid and motor.
Like I said, you can wire it with the small relay and leave what you have in place just for looks, but it takes some small changes to the connections which I'd be glad to explain when I have more time. Or do away with it altogether and wire it like an early Evo. Otherwise, here are your only 2 choices:
Sorry about my choice of words. I meant nothing by it.
Your explanation makes perfect sense, and for me begs the question of why the wire in the following diagram is necessary?
Seems to me that a hot wire from the battery to the starter, then to the relay with a fusible link is good enough. The wire from the battery to the relay seems not needed to me.
I'm not against wiring it like an evo, just never in the 40 years I've owned this bike had any sort of run on. BUT, having said that. for some odd reasons the starter system has been given me fits the last year.
Sorry about my choice of words. I meant nothing by it.
Your explanation makes perfect sense, and for me begs the question of why the wire in the following diagram is necessary?
Seems to me that a hot wire from the battery to the starter, then to the relay with a fusible link is good enough. The wire from the battery to the relay seems not needed to me.
I'm not against wiring it like an evo, just never in the 40 years I've owned this bike had any sort of run on. BUT, having said that. for some odd reasons the starter system has been given me fits the last year.
Looks like I may owe you and many countless others apologies for several reasons... After seeing what you posted which I assume is a factory manual page, I'm embarrassed thinking how many times I've posted, going on what might be incorrect info. I guess I could go on ebay and buy a dunce hat and wear that for a while
I've never seen a Factory manual wiring diagram for a Shovel. All this time I've been going by the ones I've touched in person which has been 20 years and hand drawn diagrams of what people "said" they had. The few I'd fixed myself had been butchered or had some version of "custom" and they had the battery cable to the relay, relay to solenoid long post (with a jumper to the small post) then solenoid to starter motor.
Looks like the diagram is showing different arrangements for FX vs FXE so the "extra" wire my be for that reason, as in one or the other depending on model. They're showing battery voltage going to the relay coming from different locations.
Bottom line, if yours is wired like the diagram shows then yes, a post post Bosch type relay would work just fine. Only need to change the wire ends on the harness. Those round relays do give out over the years and stick closed. Every Ford I ever owned had to be replaced at least once and they weren't that old at the time. A solenoid can get burned contacts and stick too, but I'd eliminate the relay as a possibility first.
Looks like I may owe you and many countless others apologies for several reasons... After seeing what you posted which I assume is a factory manual page, I'm embarrassed thinking how many times I've posted, going on what might be incorrect info. I guess I could go on ebay and buy a dunce hat and wear that for a while
I've never seen a Factory manual wiring diagram for a Shovel. All this time I've been going by the ones I've touched in person which has been 20 years and hand drawn diagrams of what people "said" they had. The few I'd fixed myself had been butchered or had some version of "custom" and they had the battery cable to the relay, relay to solenoid long post (with a jumper to the small post) then solenoid to starter motor.
Looks like the diagram is showing different arrangements for FX vs FXE so the "extra" wire my be for that reason, as in one or the other depending on model. They're showing battery voltage going to the relay coming from different locations.
Bottom line, if yours is wired like the diagram shows then yes, a post post Bosch type relay would work just fine. Only need to change the wire ends on the harness. Those round relays do give out over the years and stick closed. Every Ford I ever owned had to be replaced at least once and they weren't that old at the time. A solenoid can get burned contacts and stick too, but I'd eliminate the relay as a possibility first.
No apology needed. The MoCo did a lot of hooky back when AMF had it and Wille G was trying to buy it back.
That diagram is from the original factory 1977 factory manual. It looks like some sort of misprint simply because if you look all the way over to the left, it says FX for the wire to the battery that the dashed wire for the battery to relay is on. This makes no sense since the FX did not have an electric start. It was the FXE that had the electric start. Therefore, there was no relay for the wire to go to in the first place.
Interestingly enough, my bike is an FX that I traded another guy some parts decades ago for his electric start. It has worked perfect until last year. It never had that wire from the battery to the relay. Only directly to the starter, then the fused wire to the relay. It is the big round (Ford type?) relay. I'm wondering if this was some sort of mid year interim fix the MoCo made for the run on issue.
My entire start system has been replaced. I actually have gone through a couple of cheap, horrific problem riddled solenoids. I bought one from Drag Specialties that hope will work longer. I replaced the big relay, but if I have any more issues with that one, I am going the small relay route.
this is what she sounds like today after getting it all back together
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starter relay upgrade question
