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Yesterday, my car started and then shut off. After trying several times and having a strong crank and dash lights working I suspected the fuel pump fuse or relay. It was indeed the relay. (Thanks Stan * MrMerlin, for your help). I have a new relay coming tomorrow and used a fused jumper that worked fine and got me where I needed to go.
1. Is this browning of the relay socket cause for concern that may also indicate what the fix might be?
2. I did notice the relay jumper was rather hot. It would not burn the skin,but I did not want to touch it longer than half a second or so.
3. After opening and inspecting the relay I see two bad solder joints. Is this something may have occurred because the relay got hot enough to melt the solder? or, might I be able to re-flow the solder and keep this repaired relay as a spare?
resolder the relay and get some deoxit 100 on all of the connections to the relay
NOTE you will also have to drop the CE panel forward to put the D100 on the connectors at the back of the panel,
its getting hot because its not making solid contact
Would tend to indicate there has been excessive current drawn through there. I burnt out 2 pump relays before I found poor contact at the pump fuse - OB bullet fuse boards have poor grip on the fuses IMHO. When the last relay died, as I was installing the jumper I saw a spark out of the corner of my eye , which led me to the base problem. Check the fuse, and its holders - since you didnt post your model, we dont know what type of fuses you have. If bullets, you can pull the top clips of the fuses easily, clean, Deoxit, replace with more tension. While top is out clean and deoxit the bottom fuse seats.
Check here https://rennlist.com/forums/928-foru...sockets-4.html for what I have done to fit blade fuses in the high current sockets. My pump draws 7A. Faults in the wiring from the bottom of the main board to the actual pump can lead to higher than normal currents.
jp 83 Euro S AT 57k
Would tend to indicate there has been excessive current drawn through there.
This kind of damage is almost always caused by contact resistance issues at the relay terminals (excessive oxidation/corrosion usually). Clean the relay blades (chemically & gently mechanically) and the socket (chemically). Trying to clean the socket mechanically usually does more harm than good. Then use an electrical contact promoter and surface protector for long term protection
This is almost NEVER caused by excess current - most people find that hard to believe - it is always resistance that causes localized heat - it also causes LOWER circuit current - not higher current...
Alan, Seems I am mistaken. Can you explain to me the sequence in my observed case of 2 relays dying early, and a spark observed at the pump relay fuse (OB bullet)? Bad contact at the fuse holder lifting resistance, generating heat at the fuse holder I can follow, but why did the relays die? I dont recall seeing signs of heat at the relay socket.
jp 83 Euro S AT 57k
Thank you everyone. Dexoit 100 forthcoming. I may fill the swimming pool with thousands of gallons of this stuff and just give it a good dunking! ...or, maybe just remove the relay/fuse panel and give it a good cleaning.
My car is a '78 I though it was in my signature, but then realized my RL subscription has lapsed. I will renew.
JP,
The fuse sparking at its fuse-holder the terminals is not uncommon for high load circuits on the bullet fuses - if the fuses are loose or the terminals corroded.
Now in your case the build-up in contact resistance may actually have started at the relay switching terminal (inside the relay - these are close to and directly thermally attached to the external terminals). If these relay blade terminals get that hot they likely also start degrading their own contact surfaces and the relay socket - So I'd still recommend cleaning those as described. If the interior relay switch terminals get hot enough then they can either weld themselves together OR build up enough contact resistance that they fail to operate as a switch (approximately open circuit e.g. too high a resistance to effectively operate the load). There are poor quality relays out there from aftermarket sources and these degrade further and faster over time than good quality ones. If you have intermittent connections (from the fuse) to a highly inductive load (motor) then you can induce large voltage & current spikes that can cause faster terminal degradation.
I think for the OP's case the heat pattern shows most heat at the 30 terminal - clearly emanating from the blade out - so most likely an issue in the terminal connection between the relay and socket. If there was more obviously similar damage between the 30 & 87 terminals - I'd say the relay internal terminals could also be a possible culprit.
In these cases the blade terminal is very hot and can cause possible solder connection damage inside the relay as you suspected. e.g. repeated major heat cycling creates solder connection problems.
My fuse contacts are good. I cleaned them with deoxit ( Stan would be proud).
My issue was on the back of the panel where the birds nest of all black wires goes to the relay board. I had some wire coming off of about 7 different relays that daisy chained to the back that was melted and I needed the female quick disconnects that lock into the relay holes. I found some female quick disconnects but was unable to find any locking ones that would stay in the back of the panel when pushing the relays in. I was able to reuse the old ones however. So I think I am good for now.
After cleaning contacts and using Deoxit, I did notice my volt meter is up and my turn signal "click" is now audible again.
Now if this darn rain would stop, I could get out and enjoy her. I wish I could make Frenzy, but my band has to play. Everyone have a great time.
Quick test with jumper wire, yup, fuel pump relay bad and this is what I found on the panel. Plugged in a known good spare relay, gets very hot to the touch after running for a very short amount of time.
Unfortunately other projects have prevented me from digging into this until now, hope to pull the panel this weekend.
I think this below is what you need - locking female - but maybe not a crimp connection. The small strip in the centre is what does the locking into a socket, but it has to be bent out ~1/16" to ctach. The relay sockets have a narrow groove beside the socket, so you can insert a tool (~3/32"wide x 1/32" thick) to release the lock and remove the connector. Heat may have softened the brass so it doesnt lock any more. https://www.aliexpress.com/item/20-S...ceBeautifyAB=0
I think this below is what you need - locking female - but maybe not a crimp connection. The small strip in the centre is what does the locking into a socket, but it has to be bent out ~1/16" to ctach. The relay sockets have a narrow groove beside the socket, so you can insert a tool (~3/32"wide x 1/32" thick) to release the lock and remove the connector. Heat may have softened the brass so it doesnt lock any more. https://www.aliexpress.com/item/20-S...ceBeautifyAB=0
I think this below is what you need - locking female - but maybe not a crimp connection. The small strip in the centre is what does the locking into a socket, but it has to be bent out ~1/16" to ctach. The relay sockets have a narrow groove beside the socket, so you can insert a tool (~3/32"wide x 1/32" thick) to release the lock and remove the connector. Heat may have softened the brass so it doesnt lock any more.
You absolutely want a crimp connection, there are good reasons why such connections are never soldered by the factory. Anyone working on these cars should invest in a quality crimp tool.
As for the connectors, I prefer to use anything by Wurth, quality is very important here & Roger is a Wurth distributor. You can order such connections from their website, but such pieces have a minimum quantity of 100 or so.
I picked these up (by Wurth) from my local Indy mechanic who keeps such things in stock for repairs like this:
09-18-2018, 07:47 PM
Fuel Pump Relay socket looks burnt or brown?
