Melting Chinese Wutrin made relays

[TDH888]

Hi guys ,

When I was driving my 89 930 I noticed that I was loosing power again at high speed . Went home and check the 2 fuel pump relays and look what happened to this Chinese made relays . The case are starting to melt . My fuel pumps are New both Front & rear and so as the filters .

[RarlyL8]

Yes there have been a few threads on the subject. More Chinese garbage allowed to destroy the market for quality items with no consequence. Last I saw folks were buying up old used ones which is pretty sad. I have begun replacing mine with conventional new ones when I have the time. Takes more effort to re-wire but not much choice until a better option for OEM comes along.

[908/930]

So what failed on the relay? Do the contact points give up or does the coil windings smoke?

[Carbster09]

RarlyL8, I have been forced into buying the Chinese relays and have had a few fail. Sorry but I don't understand your reply ... I have begun replacing mine with conventional new ones when I have the time. Takes more effort to re-wire but not much choice until a better option for OEM comes along. If I had any other option I would take it.

By the way, I ordered one of your exhausts and had it installed at a shop that will remain nameless ... however they could not align it properly and advised me to saw the tips parallel! No, thanks ... Bergman Autowerks in Va corrected perfectly. And ... it sounds fantastic. One of the best upgrades I have done. Next on to the dyno for some tuning!

[boosted79]

Two 40A Hellas

[TDH888]

Originally Posted by 908/930

So what failed on the relay? Do the contact points give up or does the coil windings smoke?

When the tech arrives I will ask him to crack open the melted case to see why the relay failed .

[TDH888]

Originally Posted by boosted79

Two 40A Hellas

I might ask my tech to this the next time my old German relays installed fail . Why cant Porsche or the numerous Parts Vendors ( like Pelican , ***********, EBS. ,etc) to persuade Bosch or Hella to remanufacture them again . There is still a lot of 911/912 still on the road .

[Alan L]

Originally Posted by 908/930

So what failed on the relay? Do the contact points give up or does the coil windings smoke?

I run my pump relays without the covers on - so I can see what is happening when I have issues.
The high load side is the pump circuit - which is the 30/87 leg. These two pins are basically connected by a set of contact points and solid metal thru the pins. So you would have to think the grade of metal is rubbish or the contact points were crap and produced a high current load. That side of the circuit is really basic. The other side (85/86) is just the low amp energiser for the solenoid pulling the contacts in. Light gauge wire which would short out (and fail) under any severe load. So you would have to conclude the 30/87 leg is made of rubbish material and the contacts likely burnt out - creating greater resistance/heat until..... But your fuse should really have blown before that (25A?) If you are still on stock wiring you can split the two relays out to separate fuses and halve the load on any fuse and run lighter fuses - which may at least prevent the melt down.
But you still have the problem with the crap relay.
Be interested to see what is found.
Alan

[TDH888]

Originally Posted by Alan L

I run my pump relays without the covers on - so I can see what is happening when I have issues.
The high load side is the pump circuit - which is the 30/87 leg. These two pins are basically connected by a set of contact points and solid metal thru the pins. So you would have to think the grade of metal is rubbish or the contact points were crap and produced a high current load. That side of the circuit is really basic. The other side (85/86) is just the low amp energiser for the solenoid pulling the contacts in. Light gauge wire which would short out (and fail) under any severe load. So you would have to conclude the 30/87 leg is made of rubbish material and the contacts likely burnt out - creating greater resistance/heat until..... But your fuse should really have blown before that (25A?) If you are still on stock wiring you can split the two relays out to separate fuses and halve the load on any fuse and run lighter fuses - which may at least prevent the melt down.
But you still have the problem with the crap relay.
Be interested to see what is found.
Alan

Hi Alan ,

I remembered before when I was using the German made Wuttrin relays its the 25 amp fuse that melted not the relay . I will update you guys to what caused the relay meltdown .

tdh888

[T77911S]

the FP's pull about 8 amps each. if the relays cant handle 8 amps, a smaller fuse will not help anything because you cant go lower than what the FP pulls.

splitting the fuses is a great idea for keeping the fuses cool.
I split mine and made it look factory.
the hard part is figuring out which wire to cut AT the FP relay.
I then ran the cut wire over to a spare fuse slot (bottom)
then ran a red wire from the top of the same source that feeds the factory fuse over to the new FP fuse.

I don't get this. they ran power from FP RLY 2 back to power the WUR, AAR and then back up to energize the O2 sensor relay. like there was not enough load on there already.

[JFairman]

Originally Posted by TDH888

I might ask my tech to this the next time my old German relays installed fail . Why cant Porsche or the numerous Parts Vendors ( like Pelican , ***********, EBS. ,etc) to persuade Bosch or Hella to remanufacture them again . There is still a lot of 911/912 still on the road .

Take a wild guess where your generic black relays were made...
CHINA
That wiring mess with the wires pushed into the factory relay sockets is ridiculous right there next to the gas tank.

All consumer electronics are made in China now and it isn't going to change.
If you slowly and carefully squeeze the red or black cap on the Porsche relays with pliers in warm weather or after letting them sit in the sun for a few minutes they will pop off the base of the relay before they crack or break.
Then if you really want to use generic cheap relays you could remove the internal relay parts from a dead red relay and solder wires to the pins inside and run them to the male spade terminals on the generic relays.

You could also drill a hole in the red relay cap and run the wires through it before soldering them and then press the cap back on to the retaining groove around the relay base. That would look better.
Smear a tiny bit of clear silicone glue into the groove to seal it and make it stay there before pressing the cap back on.

You can buy one piece plastic relay plugs that fit the spade terminals of the generic square relays that have female spade terminals in them which is much better than 4 or 5 seperate crimped on female spade terminals. The best ones are probably under the hood of old cars in salvage yards that used the square Hella relays.
To keep it all working smear some dielectric grease on all the push on electrical connections to keep them from corroding.

[Tom F2]

Still hoping to see a post mortem on a Chinese made red relay. Remember DME relays (made in Germany by the way)? We learned to fix them, and I'll bet that we can learn how to fix the current production red relays, too.

[WinRice]

High quality, Made in Japan, 40amp automotive relays, fully sealed with a resistor buffer. Around $5 each in quantities of 10. One of the best relays I've found, and I've used them in several applications.

https://www.digikey.com/products/en?keywords=CB1a-R-12V%20

[Speedy Squirrel]

How about a solid state relay? No moving parts.

https://www.summitracing.com/parts/hla-h41773001?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-hella&gclid=EAIaIQobChMInqjdmImV2gIVi4jICh2UtQIiEAQYASAB EgI-hPD_BwE

[OldSpool87]

Originally Posted by Speedy Squirrel

How about a solid state relay? No moving parts.

https://www.summitracing.com/parts/hla-h41773001?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-hella&gclid=EAIaIQobChMInqjdmImV2gIVi4jICh2UtQIiEAQYASAB EgI-hPD_BwE

I’ve been thinking the same thing. How would one adapt this for say a fuel pump relay?

[TDH888]

Maybe one of our members can mini manufacture a new relay / fuse box were in it can use the normal cube relay & the blade type fuse .

[RarlyL8]

I’ve been thinking the same thing. How would one adapt this for say a fuel pump relay?

That's what we did with the delay relay in the engine compartment. Plan to do that with the fuel pumps when I get time. The new relay plugs into a matching square base so you replace the OEM round bases with square ones, wire it up, plug in the relays.

[WinRice]

Originally Posted by TDH888

Maybe one of our members can mini manufacture a new relay / fuse box were in it can use the normal cube relay & the blade type fuse .

Here's what I came up with, out of many options:

935 Suspension with Moton Coilovers for the street

[flightlead404]

Originally Posted by TDH888

Maybe one of our members can mini manufacture a new relay / fuse box were in it can use the normal cube relay & the blade type fuse .

I've been slowly tinkering with a 3D model of a replacement circular relay base that will accept standard "fast-on" style crimp connectors and allow a standard automotive 4 or 5 terminal relay to be used and still fit under the front relay cover.

Job and life have got in the way unfortunately, but I'll get it done soon.

[flightlead404]

Originally Posted by Speedy Squirrel

How about a solid state relay? No moving parts.

https://www.summitracing.com/parts/hla-h41773001?seid=srese1&cm_mmc=pla-google-_-shopping-_-srese1-_-hella&gclid=EAIaIQobChMInqjdmImV2gIVi4jICh2UtQIiEAQYASAB EgI-hPD_BwE

If you read the comments on this product you'll see some users claim it leaks current. Also it may not simply be plug and play.