Second Solenoid in two days

[KTM2FORD]

First timer...purchase a 1970 over the weekend, ran great for a day. wouldn't start. Tested battery, alternator both good. wasn't getting power to anything, put on a new solenoid and it fired right up. two days later I drove it to work then to lunch no issues until I had to get back to work. wouldn't start no power to the aux, when key is on. after work bought a new solenoid (#2) installed and nothing...had some aux power, gages and reverse lights worked...then nothing...i bought a rebuilt starter and am hoping that is the issue. long story short, if I have a bad starter can it short out the solenoid? what else should I check? thanks!!

 

[DirtDonk]

Hey KTM, welcome!
First of all, many new parts are crap these days. Our fault mostly, but that's another story. With these things in particular, it seems that the less you pay, the less quality you get is a true statement.

Second though, you may not have a starter or a relay (solenoid) issue in the first place.
To answer your question though, yes, a bad starter can take out a starter relay too.
But, when you're not getting power to anything, the starter system has nothing to do with it. It sounds plausible that you're fighting a wiring issue with your fusible link wire there at the solenoid/relay and maybe just messing around with it will "fix" it temporarily, only to give you grief again.

However, that's only if you have no power at to anything at all. If you have power to any of the accessories, the fusible link is not your problem after all.
The fusible link is a short section of Black wire (may have a red stripe) right there at the starter relay. Since yours is a '70, it's possible that you only have two wires on the left side large post. That would be the battery cable to the positive side of the battery and the Black wire that feeds power to all accessories, and charges the battery when the alternator is putting out.

Unfortunately, all of this is way too common after buying an Early Bronco these days. Lots of people off-loading their own problems on to a new owner. Chances are that the PO (previous owner) either didn't know about it, or knew and just couldn't figure it out.

What is the condition of the battery cables? They can get old and fail internally too, even though they look half-way decent on the outside. Sometimes it's just cheap insurance to change them out at the same time you're either changing the starter or trying to track down an intermittent fault like you're having.

Good luck. Any chance you can post up pics of the engine compartment in that battery corner? You can use one of the free online hosting sites, or post directly to the forum if you pay the 13 bucks to become a contributor.
No pressure to do it right now of course, as you just got here and might not feel you should invest in an unknown. But if you end up wanting to post a lot of images for us to check out (we love pics in case you didn't notice!) it might be worth it.

Paul

 

[DirtDonk]

Just re-read part of your post. Did you experience a total power failure after trying to start it up?
If so, then I would definitely replace the main battery cables. And for sure check the condition of that Black wire I mentioned.
I've seen fusible links kind of "partially blown" (which isn't really supposed to happen, but does) and cause intermittent issues. Many times you can literally feel the wire and the end connector to see if they feel kind of mushy and bloated like they'd melted in the past.

Check those things out.
I'm not saying you don't need a starter of course. Those fail too, but won't cause a total loss of power to the other accessories.

Paul

 

[Bulletman]

My rig was doing the same thing recently despite new battery and cables less than a year old. But when I took all the connections off and cleaned and tightened them it now starts and runs consistently like it did a few months ago when I replaced the cables. It didn't take much corrosion to give a weak and inconsistent connection.

 

[Dark Knight]

My rig was doing the same thing recently despite new battery and cables less than a year old. But when I took all the connections off and cleaned and tightened them it now starts and runs consistently like it did a few months ago when I replaced the cables. It didn't take much corrosion to give a weak and inconsistent connection.

I just had the very same issue with mine.

 

[bronconut73]

I run an Optima. They just don't corrode battery cables.
At least not in the 20+ years I have been running them.
Remember your solenoid needs a raw spot on the fender where it is mounted to ground it. I only learned that last tid bit of information a few months ago right here on CB.

 

[KTM2FORD]

thanks guys...I plan on figuring it out this w/e, I'll let you know how it goes

 

[70_Steve]

Just re-read part of your post. Did you experience a total power failure after trying to start it up?
If so, then I would definitely replace the main battery cables. And for sure check the condition of that Black wire I mentioned.

To expand on what Paul said (if that's even possible!!!)...

The stock wiring harness provides all the power for the Bronco through a loop, which starts at the BAT+ side of the starter solenoid, through that fusible link Paul mentioned, into the passenger compartment behind the dash, then back out to the alternator. There are some splices into this loop to power a couple things, like the ignition switch, headlight switch and a fuse in the fuse block.

All the accessories are powered through the ignition switch. If you have no accessories, possibly you have no power to the ignition switch. Or, maybe the ignition switch is defective... A quick check would be to turn on the headlight switch. If you have headlights, then there is power to that loop, and maybe the ignition switch is bad. If you have no headlights, then start looking at whether you have power to that loop, through the fusible link.

Here's a link to some wiring diagrams that might help. The "loop" I referred to is made up of wires 37 and 38, and the fusible link is wire 38A.

seabiscuit68.tripod.com

 

[KTM2FORD]

electrical is all good now...after replacing the solenoid again and starter...thought maybe the switch was bad...jumped the battery + to the start and it cranked...then tried again...after starring at it for and hour or so, I broke out the test meter AGAIN!!! Put it to the pos solenoid side and didn't have power??? Replaced the pos main bat cable...all good. Now it seams flooded, cranks but doesn't start...previously bought a new 570 Holley carb but wanted to fire it up before I installed it. hope to be able to fix it tomorrow.

 

[DirtDonk]

Gettin' there!

Just to make sure, when you were cranking it and it would not start, were you still cranking it with a jumper, or were you turning the key?

When the key is in RUN, check to see that you have power to the positive side of the ignition coil. Also, make sure that the Brown wire on the starter relay is hooked back up.
And if you have a radio noise suppressor (little cylinder/capacitor looking thingy) connected to the positive side of the ignition coil, temporarily disconnect it.
And if it truly is flooded, try holding the throttle down to the floor while cranking. You may know that old trick, but in case you didn't, it lets more air volume in to run the gas through the engine more quickly. Or something super scientific like that. %)

Good luck tomorrow. Working on Bronco electrical tomorrow too myself. So we'll be pulling the same hairs out no doubt!

Paul

 

[KTM2FORD]

Was cranking it at the key. Power is good....but just went to the part store for new spark plugs (looking them up by year model make 302). Got home to find the plugs are way smaller (dia) then what's in the bronco. Took them back and found the correct ones. But then the guy says to me you don't have a 302 5.0, you have a 428 7.0. Can this be true? Chance someone put different heads on it? I know very little about motors, looking forward to learning. I purchased the Holley 570 street advenger carb.to instal. Is this going to be an issue? I feel dumb but I guess that's part of learning....I'm told there should be a number on th block or heads so I can look up what I have. Anyone know were this number is located?

 

[Bluebolt]

You wish you had a 428 7.0 LOL! FE 390-427-428 swaps into early broncos are pretty rare, the parts guy just doesn't know what he is talking about. Pictures would help!

 

[hucklburry rev2]

subscribed, hoping it is a really cool engine...please add pics and/or motor #s off the block (302 is right by the starter)

 

[KTM2FORD]

Well it was a long weekend!!! Solenoid in, electrical fixed, (but still needs to be cleaned up) new starer, new plugs, new carb....then found it wasn't pulling in any fuel. Put in a new fuel pump and she fired right up. Took it for a test drive, and after about 5 min she started to backfire a little. Made some timing adjustments and ran out of weekend...I'm thinking I'm going to check the plug gaps and play with the carb some more....any other reason it would backfire?? Too lean maybe???

 

[DirtDonk]

1. Too lean
2. Vacuum leak (same results as above, but could have different sources)
3. Valvetrain issue.
4. Incorrect firing order on the spark plugs (but would have done it from the beginning)
5. Insert your own SWAG here... ;D

Pics would help and we like seeing everyone's rigs (and engine compartments!) anyway.
Someone here will know, and I've seen the discussions about plug changes but don't remember the details. Pretty sure Ford used different plug sizes in different year EB
s. And after 44 years even the heads could have been swapped out for those from some other model year or even a 351w perhaps.

Glad you got it fired up and running for the most part. Sounds like you're narrowing it down, and fixing all the issues the PO had and couldn't deal with.

Paul