Fuel injector splice and protective wrap (2 Viewers)

[CharlieS]

I mentioned on another thread that I was having my injectors rebuilt for my 1994 1FZ. I had ordered connectors from Ballinger Motorsports, but once I looked closely at the injector wires, I found two with broken sheathing/exposed wire and two that were cooked along a significant length and the sheathing was broken in two places on both wires (#6 by EGR, no surprise). The pins on #6 were very corroded too.

So I reached back out to Ballinger and ordered a set of connectors with pigtails (yes, I could have spliced my own, but would prefer the peace of mind of a known good crimp on the injector connection pins).

My first question is how do people recommend attaching these pigtails to the factory loom? Crimp butt connector, solder the joint, something else?

My second question: to inspect the wires, I destructively removed the plastic wire loom cover around the wires to each injector. I'd like to replace it with something suitable. I could use heat shrink, wire loom or something else, but don't know what approach might be best. Is there a product available that is similar to the factory protective wire loom cover? Does anyone have recommendations?

 

[jonheld]

My first question is how do people recommend attaching these pigtails to the factory loom? Crimp butt connector, solder the joint, something else?

You will get several answers. I prefer solder with heat shrink, but I've been working with soldering irons since the 1980s. A bad solder joint is just asking for trouble. If your skills are questionable, then crimp connections are better, but you need a good crimp tool to ensure a proper connection.

Is there a product available that is similar to the factory protective wire loom cover? Does anyone have recommendations?

Have a look at McMaster. I've used spiral wrap with very good results in high abrasion areas. IME split loom tends to degrade quickly. They stock many different types of protective coverings and have very quick delivery.

 

[Fj80oregon]

I love a good solder joint but in an engine bay that has lots of heat cycles and vibration a crimp is the way to go. Toyota crimps all the connections in the engine bay and even recommends not to solder. Even though a proper solder joint will last a very long time. I use a nice crimp tool and try not to buy the cheapest connectors. I did what your doing and crimped each one then heat shrunk for water proofing.
Klein Tools 3005CR Wire Crimper Tool, Ratcheting Insulated Terminal Crimper for 10 to 22 AWG Wire https://a.co/d/cYc8ODK

 

[ZackR]

I'd use an insulated butt splice connector with built in heat shrink and slide another bigger piece of heat shrink over the whole connector.

 

[Marvelicious]

I've been hearing for years about the dangers of vibration on soldered connections. It's absolutely valid on connectors where the connector is stationary and the wire can move, but I just don't buy it with splices. A properly soldered and heat-shrunk lineman splice is about as stable a connection as you can get. It's good enough for NASA, so it'll probably be okay in your Landcruiser.

NASA SP-5936 (03) and NASA SP-5936 (04) are free if anyone really wants to nerd-out about it. Really exciting reading...

 

[CharlieS]

Thanks!

I googled those publications, and only found the first one. I skimmed it and didn't see any wire splice info. Maybe if I read it I will find it. That's mire detailed info than I'm used to.

 

[Marvelicious]

Thanks!

I googled those publications, and only found the first one. I skimmed it and didn't see any wire splice info. Maybe if I read it I will find it. That's mire detailed info than I'm used to.

The second one covers splices...

I think maybe I had the number wrong... going from memory.

Here's a link.

https://standards.nasa.gov/sites/default/files/standards/NASA/A/4/nasa-std-87394a_w_change_4_0.pdf

 

[jonheld]

I've been hearing for years about the dangers of vibration on soldered connections. It's absolutely valid on connectors where the connector is stationary and the wire can move, but I just don't buy it with splices. A properly soldered and heat-shrunk lineman splice is about as stable a connection as you can get. It's good enough for NASA, so it'll probably be okay in your Landcruiser.

NASA SP-5936 (03) and NASA SP-5936 (04) are free if anyone really wants to nerd-out about it. Really exciting reading...

Yea, I kind of rolled my eyes as well, but decided to let @CharlieS make the decision based on his skill level. Good soldering skills take time to develop, just like anything else. After 4 or 5 thousand you get pretty good at it.
In the last 40 years I've never had a solder splice fracture, but I've been doing it a while and understand how things work.

 

[CharlieS]

Thank you all.

I've been soldering for a long time and am confident that I can do a decent job. I'm also pleased to see that some of the splicing techniques I've used come from the space program. I thought they came from A&P practices.

I've seen some motorsport wiring training videos (Haltech maybe?) where they comment about mechanical damage and failed joints, so it's good to get some experienced real world advice. Even those videos say that soldering can be okay with proper strain relief (they recommend adhesive lined shrink wrap), so they seem to acknowledge that it is an acceptable practice.

I found some pvc wire protection that looks in pictures an awful lot like the stuff that came off, so I ordered some. I'll report back once I have it in hand.

Thanks again all.

 

[Marvelicious]

Yea, I kind of rolled my eyes as well, but decided to let @CharlieS make the decision based on his skill level. Good soldering skills take time to develop, just like anything else. After 4 or 5 thousand you get pretty good at it.
In the last 40 years I've never had a solder splice fracture, but I've been doing it a while and understand how things work.

I'm pretty sure some of that anti-solder bias comes from the military aircraft world and if it were my job to dumbass-proof a process for the military, I'd probably specify crimping as well. I've definitely heard it repeated with authority by aircraft mechanics and I think most of them get their training in uniform.

Thank you all.

I've been soldering for a long time and am confident that I can do a decent job. I'm also pleased to see that some of the splicing techniques I've used come from the space program. I thought they came from A&P practices.

I've seen some motorsport wiring training videos (Haltech maybe?) where they comment about mechanical damage and failed joints, so it's good to get some experienced real world advice. Even those videos say that soldering can be okay with proper strain relief (they recommend adhesive lined shrink wrap), so they seem to acknowledge that it is an acceptable practice.

I found some pvc wire protection that looks in pictures an awful lot like the stuff that came off, so I ordered some. I'll report back once I have it in hand.

Thanks again all.

That Western Union splice, AKA Lineman splice, AKA telegraph splice is a lot older than NASA, but it has held up for me on everything from motorcycles to guitar amps to espresso machines to... I have too many hobbies. Come to think of it, I've got at least one guitar amp that predates NASA.

If you're doing it right, it's a solid connection before you add the solder. The heat shrink on top is basically just strain-relief. Sounds to me like you've got it well in hand though.