I swapped a 351w from an 1986 to 1983 f150 4x4. Everything went pretty well. However, I can't seem to get an eletrical problem right. Everytime I hook up the positive terminal on the battery it sparks and even smoked my starter solenoid. I really don't know what the problem is. I think it may could be the alternator but am unsure. If I disconnect the alternator and then connect the battery it is o.k. However, if I try to hook the alternator up again I have the same spark/smoke problem. I may have the alternator hooked up wrong don't really know. I only have two wires to hook to it.. A black which I assume is ground and a red with a red boot on it which I have tried to hook to the "stat" side on the distributor and one other pole at the bottom. Nothing seems to work they all spark when the positive is hooked up to the battery.. I am a novice so please go easy on me.. thanks

 

I tried to find you a wiring diagram online but came up empty handed. Have you tried looking in the manual? I found the diagrams in my manual to be very helpful.

 

what has me a little crazy on this is that there is only a couple of ways it could hook up.. The problem with the sparking is strange to me. I don't understand how even if I hooked it up wrong it would spark like that. I thought you had to have a serious problem with the wiring to get sparking and smoking etc.. Maybe miswiring of the alternator is serious enough to cause that.. not sure..

 

also.. I had a 1983 351W in the truck and swapped it with an 1986 351w HO.. I don't think that makes a difference but not sure.

 

I wouldn't think it would make that much of a difference.

Have you taken your alternator in to have it tested?

 

no I didn't have it tested. I guess that is the next thing to do.. Go and have the alternator tested. It was working a few months ago but maybe something happened to it.. Still wonder though if you have a bad alternator if it can cause sparking at the battery.?? Seems strange.. Like I have something wired wrong.... I thought even if the alternator was bad it wouldn't cause this problem..

 

If it turns out the alternator is now bad, I would suspect the obvious miswiring of
and/or problems with the charging system - perhaps blown-out diodes in the
alternator - as the cause. The fact that you're causing large sparks and letting the
smoke out of the devices should tell you that you're hooking something up VERY
wrong. Size & type of engine doesn't matter; what matters is if it's a 1G, 2G or
3G alternator & charging system.

EDIT: Also, there are different wiring configurations depending on if you have a factory
ammeter on the dash or merely an idiot light.

I think Franklin2 has diagrams in his Gallery, you might check there but I'd also
suggest asking in the Electrical forum (of which he is a moderator):
https://www.ford-trucks.com/forums/forum62/

 

Did you mess with any other electrical things in the truck brfore or during the swap?

 

Can you post a picture of the alternator? Is the alternator out of the 1983? Is it internal or external regulated? I read that you hooked the alternator to the dist, did I read right? The alternator definately does not go to the dist, BUT please post a picture, so we can help and determine what you have.

 

Thanks for the replies. I will try and get a pic for ya. However, the alternator is a back connection type from the 1983 in the same configuration (using the brackets etc from the old engine). The connections are the same to the alternator although I may have them connected to the wrong poles (i tried several different ways though). I am using the same coil. I changed the starter solenoid after I smoked the first one. I changed the starter cable to the solenoid because I thought that might be the problem. I tightened/looked at the ground (ground is on the engine block in front/slightly below the exhaust header passengers side. Only thing I find consistent is that when I disconnect the alternator I don't get the sparking. I don't want to jump to conclusions though and say it is the alternator because miswired or not I didn't think an alternator could throw a charge out like that (maybe I am wrong). My ignition switch on the truck always has been a little squirrelly too and I think someone replaced it at some point. Anyway, I just don't understand how I can be getting such a surge at the battery.. Something has to be really wrong ? right ? My son played with the radio in the cab a little since I have been working on it but I really don't see how that would make that much difference either. It is like a "bad" spark.. not a slight "static" spark when connected. If I were to keep it connected it will fry something pretty quick.. have had a few sparks at various times when trying to connnect the positive coming from the alternator and what appeared to even be the coil. just scratching my head.. I know I haven't goofed something that bad.. Any help is appreciated.. I will get the alternator tested at the auto parts store soon.

 

Alternators can and will throw a charge out like that if the regulator is bad. They put out enought charge that they can be used to weld (I have one in my truck).

 

Okay, I did a little bit of a search, and found a diagram of the 1g alternator wiring on this site: http://images.google.com/imgres?imgu...zzKZOKswOr2-Rd maybe it will help. It is about 3/4 down the page and is the top diagram.

 

This is very important, and will need an answer to this question if I am to help.

Does the truck have ammeter and Oil pressure gauges, or does it have idiot lamps?

After I get an answer to the above question, I can help you wire the altenator and regulator correctly.


And some info....

The stock altenator can put out 100 Amps if you have the 100 amp alt.

100 amps is more than enough to run a modest home, etc..., fry you like an egg etc...

Even the most comon 60 amp altenator can kill.

Remember it's not the volts, it's the amperage that's the most dangerous.

 

truck has idiot lights only.. sounds like the alternator then.. The way I have tried to wire it so far.. Since it only has 2 leads one black with connector and one orange/red with a boot.. I have attached the black wire to the ground on the alt and the orange/red to the stat connection.. either way I get a spark.. When not attached no spark. thanks

 

Alright, I think I see your problems. You have the altenator seriously miswired.

The Black/Orange Stripe wire isn't ground. It's the main battery feed, and hooks to the starter solenoid. This is how the altenator charges the battery.

The Orange/Lt. Blue wire is the field connection to the external regulator.

You should have a White/Black stripe wire, this hooks to the Electric choke, and the I terminal on the regulator.

There should be three connections on the 1983 altenator and harness.

1: Black/Orange Stripe wire. This wire hooks to the BATT or B terminal of the altenator. (Not Ground)
2: Orange/Lt. Blue stripe wire. This wire hooks up to the FIELD or F terminal of the altenator
3: White/Black stripe: this wire hooks to the STATOR or S connection.


Question 2: are you using the 1986 altenator with the 1983 wiring harness? If you are, then you need to get the right altenator for the right year with the correct amperage for the truck wiring. If you are using the 1986 altenator wiring, you need to use the 1983 wiring, with a 1983 altenator of the correct amperage for the stock wiring.