1994 4 cyl Ranger, loose fuel pump relay

Maintenance/Repairs
1

I am in rural Mexico, in the mountains of the Central Highlands. If we were in the US, this would perhaps be a minor problem. A cousin has an old 1994 Ranger. The fuel pump relay, located in the engine compartment fuse box. went bad, so he got a new relay.

Now, it does not plug in securely, so sometimes he has to open the hood and fuse box and wiggle it to make contact.

Ideally, one would probably replace the fuse box, though that would apparently involve a lot of wiring, right?

Does anyone have any ideas on how to “cob” this up so the contacts will make better?

Perhaps something to put in the slots to increase pressure on the blades?

Maybe gently twist the blades so they go in at an angle?

Maybe touch the blades with a solder iron and put on a small blob of solder to make the blade bigger? (Though it seems to me that solder is not a good contact material?

Maybe solder to the blades, a very small piece of brass or similar material?

Put a piece of aluminum foil over the blades?

thanks for any ideas, though the ideas of true “cob up” experts especially appreciated. Thanks.

2

The fuse panel might plug into the wire harness and if so that would make it fairly easy to replace the whole panel. If it doesn’t have a plug on it then it may be best to purchase a seperate relay socket to plug the new relay into. Then remove the wires to the relay from the fuse panel and solder them onto the new relay socket. Once contacts have been burned so badly it really is best to replace them with something new.

3

He could try removing the relay and slightly twist the relay pins so when it’s plugged back in it grips the relay socket tighter.

Tester

4

Okay, that was on my list of possibles, but I have no experience to know what will actually work. He paid 30 pesos, around $2.50 USD for a new Brand X relay, so I would suggest getting a spare before we put on the muscle.

I stopped at Auto Zone in Tehuacan yesterday, and they wanted 119 pesos, around $10 USD for a Duralast relay.

I think I will suggest that, get a spare in case twisting wrecks the relay, then twist away.

Thanks.

5

If a jumper wire is installed to connect 30 to 87

http://www.teamrocs.com/technical/pages/relay_basics.htm

the relay’s circuit will be made. But the fuel pump will continue to run even if the key is off.

6

Are there accessible wires coming up to the relay socket?
I would cut those one by one and solder them directly to the relay.
Then strap the relay down against something stable with tie-wraps.

7

You might find yourself opening a can of worms if you get into the circuits in the relay/fuse box.

8

Saturday, he drove that pickup to my house to drop his little girls off, for English class, then while we talked English, the parents went down town. An hour later, they came back in time to pick up the kids. It wouldn’t start. I saw him unplugging the two relays on that box, and swapping them around. His middle daughter, around 8, is very sensitive and she started crying because the Ranger would not start. Poor girl! She is so adorable, almost like a little pixie.

While I waited, I was thinking back. She was a baby when the Swine Flu came a few years ago. She got a really bad respiratory problem, and I drove them to a good hospital about 45 minutes away so they could aspirate her lungs every so often. Her dad had the pickup and they had a car, but the documents were not up to date so they asked me to drive them to the town, and there are transitos there. Isn’t if funny how our memories work?

Anyway, after the swap, it started and he drove them home. So, the problem apparently still exists. Sigh! I need to talk to him when I get a chance.

The usual suspects whine when an old posting is brought up. This five year old posting was listed after the page I was reading. So, for whatever reason, the old postings are displayed for the users as a suggestion. And, it was my posting, and I had update information.

9

So … the update is, nothing has changed in 5 years. Except the age of the vehicle and people involved. Is that really an update? Just asking.

1 Like
10

Twisting the blades will significantly reduce the surface contact area and the current carrying capability of the connection.
If you cannot remove the female contact and preferably replace or squeeze it back together, then a spacer would be my next choice.

Solder alone will cold flow under pressure and eventually loosen back up again.
Wrapping the blade with small gauge wire strands and then soldering would work. Or some copper foil. Heck, even some non-conducting spacer would probably work as full contact on the other side is probably OK. I would not use aluminum foil, that will react with the other metals and corrode over time.

11

I’m impressed that the old Ranger is still hanging on. No wonder I have seen so many being driven and towed to the border. Ford still makes Jalapes it seems.

12

Sigh. Opinions will differ. I Happen to believe the fact the pickup still manages to run, and still has the same problem after five years is news of value. I wonder if some place like Rock Auto has replacement boards for that vehicle. I will try to remember to look for it. I suppose it’s called a fuse block?

@TT I like those ideas, not sure about the solder one, if it is going to cold flow, but with careful soldering, it could leave the wire touching, not the relay blade. Gotta’ think about it.

I think this is a common problem here with a lot of Rangers running around. Anywhere near the border old Rangers are fairly high priced, because they know the Mexicans want them. This is due to a law in Mexico which allows rural people to import small pickups over ten years old. I looked for one for a brother-in-law and one had to go beyond Oklahoma to find one at a correct price for old junk.

I know a long time ago I parked at a store in the second biggest city in our state. Next to me was a man waiting for a family member to drive in two or three hours because he couldn’t get his Ranger started. At that time, I had no idea about the relay connections, but in retrospect, that was probably the problem. Now, I know to have him turn on the key and listen for that relay, and if it doesn’t click move it around to see if it is a contact problem.

@RK Yes, they are very common in the country here. Also, the S-10 and Nissan pickups. A few Toyotas, but not so many. Once they get them here they can keep them running almost forever, one way or another.

A cousin has an old 1976 Chevrolet pickup. The first time I saw that, I thought it was disgusting. But over 15 years, I wouldn’t mind having one, heh, heh. He had heavy duty springs put on it and he carries at times well over a ton on farm roads.

A few months ago, he had someone install a front end, of the body, around the hood and motor compartment from I think he said a 1980 pickup. The lights were different, of course, but out here he doesn’t care. The cops don’t bother farmers a lot about their beat-up vehicles if they stay out of the metro areas. Lights out, fenders beat up, and the state cops pay no attention out here.

13

It’s no myth- a well known phenomenon. Tinning of stranded wire going into a terminal block is disallowed for this reason- https://books.google.ca/books?id=-Mg1d6FvHfEC&pg=PA104&lpg=PA104&dq=solder+stranded+wires+terminal+block+cold+flow&source=bl&ots=N663erXYtY&sig=2LRh9Jr9pikKi5EEvagk34PWG_4&hl=en&sa=X&redir_esc=y#v=onepage&q=solder%20stranded%20wires%20terminal%20block%20cold%20flow&f=false

Ask me how I know- my first job out of college I got saddled with R&R about a 100 systems with 50+ terminal blocks each where the production people had tinned stranded wire. Every single one was loose after a month in the field. I had to remove, cut and re-strip every single connection…

The idea of the wire wrapped around the terminal is to create a wider terminal using the same base material as the terminal. The solder holds it in place during insertion and improves the electrical interface between the wire and terminal.

1 Like
14

The way VW fixed that problem on my Rabbit, where the contacts inside the relay plate for the fuel pump relay got damaged by excessive heat, they soldered wires directly onto the high current legs of the relay, then plugged it back in for the low current signals, and bypassed the relay plate altogether for the high current signals, soldering the other end of the wire to the outgoing wire after the relay plate. In that case the relay wasn’t falling out though, just not making good electrical contact b/c of heat caused corrosion.

15

Good info here in the last two postings, thanks ever so much.