1102 replies to this topic

[Bigfella237]

Depending on the fan(s) a 20A fuse might even be cutting it fine, do you have anything like a LED / light in the car to tell you they're working?

 

I think you kept the factory temp "idiot light" in the dash working anyway didn't you (I recall you wrestling with 3 different senders in the manifold)? That will hopefully warn you if the fans don't cut in.

 

You will iron-out all these bugs over time anyway, just carry some spare fuses in the glove box.

 

Just 2 tiny things to add to your list too...

 

For rego they will probably want to see rubber grommets around the brake lines where they run through the inner guards.

 

And for the sake of a few bucks it would be worth getting those plastic separators for the spark plug leads, something like these...

 

 

https://www.ebay.com...5.c100005.m1851

 

You're not supposed to cable tie high tension wires together like that because it can cause misfires (the spark travelling through one wire induces voltage into another), brand new leads aren't as bad for this as older leads but for a few bucks it's better safe than sorry.

Edited by Bigfella237, 03 February 2018 - 04:33 PM.

[Bigfella237]

Good point Tony, but looking at the picture above it all looks like 50A wire to me. so I assume it'd be okay (but you know what they say about assumption)...

 

EDIT: BTW, that negative battery lead isn't looking all that flash either, Mat?

Edited by Bigfella237, 04 February 2018 - 06:48 AM.

[Rockoz]

The fuse is there to protect nothing but the wires.

It isnt there to protect the fan.

The wire is protected so that it doesnt overheat and cause lots of smoke to come out of lots of wires.

Motors can typically draw 3 to 4 times their rated current and more when they start up.

Thats why you use a bigger fuse.

Rate the fuse to the size of the wire. Nothing else.

The bigger the wire the bigger the fuse you can use.

[Shiney005]

The fuse is there to protect nothing but the wires.

I never thought of it that way Rob. Great bit of info there.

[koalasprint]

Now you are getting to a more enjoyable stage. Car is running and getting onto those little jobs. It actually never ends you know.....

Anyway I thought I could help with the fuse/wire size thing.

 

Cable size Rating in Amps 1mm - 15.5A, 1.5mm - 20A, 2.5mm - 27A, 4mm - 37A.

 

Cheers, Steve.

Edited by koalasprint, 06 February 2018 - 06:21 AM.

[Rockoz]

Would consider those slightly high in their ratings Steve.

But near enough to not confuse the issue.

The longer the run of wire, the bigger you should make it.

If you fit relays, they get best effect when mounted as close as possible to the part they are powering.

Relays can be considered to fall into 2 broad types.

1. Taking the load off the switch that operates the part.

Micro switches are great for being built into smaller assemblies, but cant handle much current.

So the micro switch operates a relay using low current. The relay does the high current switching.

 

2. Reducing voltage drop on high current parts with long wiring lengths.

Ideally the relay is supplied with a larger than required wire. The relay is placed as close to the part as possible.

A smaller wire can then be used from the relay to the part without having voltage drop issues.

 

An extreme example of bad relay placement would be having the relay next to the battery supplying a high current drawing part on the other side or end of the car.

 

A lot of the relays in modern cars are to take the load off the switch, which may actually be the computer in many cases.

[Rockoz]

Electrics are a magic art.

All electricals work on internal smoke principles.

Rule 1. Dont let the smoke out.

 

Auto electrics on the old girls is actually pretty simple.

Earths will always be the number1 problem. Bad earth connections that is.

These days some of the glass fuses are a problem. Bad manufacture where the fuse wire doesnt always connect to the end caps.

The fuse panels will sometimes give dramas with corrosion on the clips that hold the fuses in place.

The old grey ink eraser is good for cleaning them up.

Some of the cars will have had some atrocious add ons over the years.

Twist and tape isnt a great way of connecting things up.

Insulation tape unravels over the years.

The harness connectors are usually okay except near the battery, where the acid environment doesnt do them many favours.

A 3 buck test light will help solve 90% of problems.

If you have dramas just ask.

I can work most issues out by asking a few questions.

I usually give a few things to check. Others do too. Im not alone in knowledge.

Follow the tests and nothing else and report back your findings.

 

Hope you dont have too many dramas anyway.

[Bigfella237]

Fix the linkage problem underneath first, there's a good chance that will take the pressure off the shifter detent and solve your button problem as well?

[Rockoz]

What sort of connectors did you use?

Have found with a lot of connectors that if they arent secured, the weight of them and a bit of vibration ends up with the wire breaking at the connector.

By far the best way to join wires in a car is soldered and heatshrinked.

Before someone goes off about standard connectors, they generally have a few extra wires in the connector that offer a degree of support.

A single connector left dangling is likely to cause future problems.

 

[Rockoz]

Mat

 

Ive crimped countless thousands of joins.

Even the most practised person will stuff up one every now and then.

My last one, and first one I didnt notice for years, happened to be on my own fridge I was fixing.

Problem had me scratching my head for ages.

Found it by accident looking for something else.

With solder and heatshrink you know you have done a good job before you move on.

[Shiney005]

I've used a few soldering irons over the years,(including the ones you heat up with an oxy) but I recently purchased a Weller Pyropen and it is brilliant. It doesn't matter how cold or windy the day is. It just does the job every time. It may be overkill for what you are doing Matt, because you can buy much cheaper ones, but I reckon mine will do me for life.

 WPA2_1.jpg   84.61K   7 downloads

 

A couple of questions for you Rob.  What do you think of the Narva connectors that have the solder built into heat shrink? 

                                                         And is there a way that you can treat old discoloured wire so that solder will stick to it?

 

[Rockoz]

Had never seen that before. Heatshrink with solder.

Looking at it I personally would steer clear of it.

I like having a look at my solder joints when done.

Those gas soldering irons are great but be careful where you store them.

Ive used one on and off for years and they are great for a quick job.

But if I am doing any large amounts of soldering I will plug in an electris one every time.

An electric one maintains heat a lot better, and for people just learning to solder that has ita own advantages.

 

Solder joints in wires need to have mechanical as well as electrical strength.

The wires should be well twisted together to gain the mechanical strength, and then the solder gives them the electrical strength.

If you have a join where the wires are just laid side by side, you can end up with problems if the wire has a tendency to get hot.

The solder can soften, the wires pull slightly apart, and if vibration i present it may become what is called a dry joint.

The solder will look dull, and the surface will take on an appearance sort of like what happens if you try to use bog that has almost gone off.

You get the lumpy sandy kind of look.

 

For joining wires that have become oxidised, gone all dark coloured there are ways of fixing it.

Because of the age of the cars we play with, it will be common to find, and not likely to be because of anything bad. Acid etc.

A lot of the time, cutting a few inches back will get you to bright copper, which will solder normally.

But knowing the old cars, that sometimes isnt feasible because you dont have much spare length to play with, or the wire will be like it the entire length.

 

Acid will clean up the wires, but really not the best way.

 

I would fall back to the old grey part of the rubber for this.

Perhaps using two with the wire in between might be easier. Splay the individual strands out first.

Bit of wet and dry and give each strand a rub will do the trick too.

There is no point soldering unless the wires are clean. It just wont work.

Some may be better off having crimp joins done and heatshrink. Prefer non insulated crimps because they dont have the thick plastic insulator.

If you search around specialty electrical suppliers you can get them down to really small sizes. 

Not always an easy job though.

A stainless wire brush on a dremel will help.

 

The corrosion on the wire doesnt seem to have much effect on the conductivity of the wire, but you wont get solder to stick.