Time to run hard brake lines and fuel lines! What do I need?

[kaoss]

So my body off custom restore on my 1977 620 is ready for brake lines and fuel lines. I'd like to get these ran to the back while the cab is off and before I paint the frame. I'm not worried about length I can use a tape measure.

 

For the brakes, I assume one line to the back but I want to delete what I assume is the load sensor under the cab, I really can't find any information on this thing, what's the deal with it? And are these trucks standard or metric, and what size do I need?

 

Fuel lines aren't as important, I assume there are three going to the back, but I also have swapped on a l16 intake, so I'm not sure if they are needed or not.

 

Any input is appreciated!

[ggzilla]

1970s Datsuns are metric. Datsun pretty much changed from Imperial to Metric around 1967. Well except for the wheels.

 

You need two of the three fuel tank lines (feed + vent lines). The 3rd line is for the return line, which is a very good thing, but you don't need it (it just might vapor lock every once in a while without the return line).

 

The brake load sensor is so the brakes don't lock up prematurely when carrying a load. If this is a just-for-show truck (never hauling anything like a real pickup) then there is no need for it.

[DanielC]

521 trucks have SAE threads on the body parts. 620 trucks switched to metric.

[datzenmike]

Actually the NLSV allows more brake pressure to the back when carrying a load. More weight means more rear wheel traction means more braking can be applied without lock-up. Or to look at it another way it reduces brake pressure to the rears when not carrying a load. If you remove it, full brake pressure will be applied at all times. Not really a good idea.

 

I suppose you could plumb a brake pressure adjuster in line but why remove one to put another in when one is already there?

[kaoss]

So does this valve work based on its position vs. sitting parallel with the ground? The truck is bagged, I'm not sure what "normal" ride position is so it seems to me that it would be off anyways depending on what position the truck is sitting is going down the road.

[kaoss]

Seems like I need this, http://www.jegs.com/i/JEGS-Performance-Products/555/63020/10002/-1?parentProductId=755192 but going to have to get it to fit metric.

[datzenmike]

So does this valve work based on its position vs. sitting parallel with the ground? The truck is bagged, I'm not sure what "normal" ride position is so it seems to me that it would be off anyways depending on what position the truck is sitting is going down the road.

 

Normally the truck has a slight downward stance to the front. The NLSV is mounted on the frame with the front tilted up slightly. There's a large steel ball with a spring and under deceleration from braking, the ball rolls up the incline and closes off the brake pressure. When there is a load in the back, the tilt of the frame (down at the back and up at the front) increases the NLSV angle also and makes it harder for the ball to roll up the steeper incline so more brake pressure gets past to the rear wheels.

 

With this info you decide.

[ggzilla]

You can do the same as other 620 customs, after putting the rake where you will normally drive it, level out the switch. Lowering up or down doesn't matter, it is the front-to-rear angle that counts.

[I'm BLUE]

Kaoss I have a "wilwood" apv. It does not need to be metric thread. Use only metric where you need it to be! Either require 3/16" line so it really doesn't matter in reality if all are metric or standard. Unless you're a purist then that's totally understandable :).

 

Standard thread for the apv you're looking at should be 3/8'-24 . Very common and very cheap.

 

As far as thread sizes. I am a z car guy not a 620 owner (yet). I have found most of the fittings to be m10x1.00 on my 240z stuff and i think? 280zx as well. I will need to flare (1) m12x1.00 fitting but my metric flare kit did not come with it so i will have to hunt ha.

 

Buyer beware as they do sell fine and course thread m10x1.00 fittings.

 

Standard fittings/Brass T's / hoses / converters seem to be 2x as cheap as metric.

 

I avoid AN fittings where i can for my purposes. They are neccessary/useful in some applications though.

[kaoss]

The stock unit is big and bulky, I'll run something though, the more I read about it the more I need to reduce the pressure to the rear.

 

So the lines are metric or standard, were all of the fittings are the same? I never new that, it doesn't matter to me, I just want to be able to stop the truck.

[budsaipan]

I just finished bending my lines for my 79 620. I ordered a 20ft line off ebay and came with 10 fittings all for about 20 some bucks.

[kaoss]

You don't happen to have a link do you?

[I'm BLUE]

I ordered from both company's below with success multiple times.

Shipping time is good as well.

the tubing cutter below works.

the cheapo tubing bender works ( made of aluminum)

the flare tool works ( don't "cinch" down on the adapters very hard or they will break. Remember to chamfer/deburr lines before flaring! )

all items in links below are 45 degree inverted flare.

 

Jegs - 3/16" copperized steel brake line coil 25ft = $16

http://www.jegs.com/i/JEGS+Performance+Products/555/63031/10002/-1

 

* metric brake fittings ( 3/16" tubing / brake 3-way t's /m10x1.0 and m12x1.0 I have ordered from here. You probably only really need m10x1.0 ... don't let the lengths scare you ) :)

http://store.fedhillusa.com/316475mmtubingandnuts.aspx = I spent about $40 something bucks because the metric 3-way t was like over $20 lol.

 

*jegs - brake tubing cutter = $8

http://www.jegs.com/i/JEGS-Performance-Products/555/80085/10002/-1

 

Jegs - wilwood proprotioning valve = $42 ( two 3/8"-24 brake fittings supplied which is made for 3/16" brake line)

http://www.jegs.com/i/Wilwood/950/260-8419/10002/-1

 

*Jegs - residual pressure valve =$17 (you will want one for driving occasionally or all the time .. if you cut yours/have a cruded up or bad one/ don't have one)

**2LB = for rear disc brakes

**10LB = version = for rear drum brakes.

http://www.jegs.com/i/Wilwood/950/260-1874/10002/-1

 

*jegs - 3/16" 25ft steel brake line/SAE flare tool/tubing cutter/a few 3/8"-24 sae fittings/combination kit = $80 !?-ish. ( you will still need metric flare tool !) http://www.jegs.com/i/JEGS+Performance+Products/555/63030K/10002/-1

 

Note: I like AN fittings for fuel line systems :).

 

Note: I could be wrong but to my understanding ... stainless lines require DIFFERENT style slip tube brake line nuts to my knowledge. I also heard stainless brake line is less forgiving in the bending process ... ( cracks are more likely) if not cared for. I have no personal experience.

 

Note: AN fittings require a 37 degree flare ... again for brake systems ..

I just stay away from them. Why convert when you can get the correct ones right? There is a time and place for them but I dont believe in "adapters on adapters to adapters" type brake hard line systems. It's just false economy. Unless needed then different story.

 

Note: instead of buying the combo kit above ^^^ you may wish to buy everything individually EXCLUDING the SAE flare tool. Now that you have the link/source for metric brake nuts just put the money into a metric brake flare tool kit ;). Do what's best/cheapest for you man :cool:. If it were me and since they would never come off again I would go cheapest route if it's significant savings.

 

Remember where an owner may care about having "period correct" fittings your car does not haha :).

[budsaipan]

This is who I ordered from. Email or message the user and tell him that you want the japanese style inverted fittings. i'll see if I can find my exact email to him regarding this. I got the wrong fittings from him the first time but he resend the correct fittings for free.

 

http://www.ebay.com/itm/Steel-Brake-Line-Tubing-Kit-3-16-O-D-x-25-foot-Coil-with-10mm-1-0-fittings-/390423260052?pt=Motors_Car_Truck_Parts_Accessories&hash=item5ae70a2b94&vxp=mtr#ht_599wt_778

[budsaipan]

This is the flares you need to ask for. (Same seller)

 

 

Metric Invert Flare Steel Tube Nuts 10mm x 1.0

 

 

http://www.ebay.com/itm/Metric-Invert-Flare-Steel-Tube-Nuts-10mm-x-1-0-Pkg-5-/370612247767?pt=Motors_Car_Truck_Parts_Accessories&hash=item564a361cd7#ht_500wt_795

[kaoss]

This is great! Thanks for the info.

[Master-O-Turbonics]

So im going to build lines for my 521... 720 chassis and rear axle, Chrysler dana44 front axle.

Im thinking of running both outputs of a datsun 15/16 or 1" master cylinder to a single brake bias adjuster in the cab and then out to the wheels...

I assume the 720 axle is metric?

Thoughts?

 

Also, I have a 25' spool of brake line, but is there any good way to straighten it out really straight?

Nobody locally(enough) has long straight brake lines...

[metalmonkey47]

So im going to build lines for my 521... 720 chassis and rear axle, Chrysler dana44 front axle.

Im thinking of running both outputs of a datsun 15/16 or 1" master cylinder to a single brake bias adjuster in the cab and then out to the wheels...

I assume the 720 axle is metric?

Thoughts?

 

Also, I have a 25' spool of brake line, but is there any good way to straighten it out really straight?

Nobody locally(enough) has long straight brake lines...

 

One of my brake shops recommended getting it nice and hot with a heat gun (not a torch because you don't want to burn off the zinc coating or whatever) and pull it straight. Leather gloves recommended.

 

This method comes straight from a 20 year Datsun veteran and master mechanic. Wish I still knew where to find him.

[kaoss]

There is a tool for straightening out brakes lines.

[budsaipan]

I just used the most basic tools too just straight them out. Used my hands on certain bends but becareful cause it can mess up easily. Anyway the only hard part is the double flare. I broke two of flaring tool trying to flare it.. The pointy thing on the flare tool is crooked. I'm contemplating on getting a quality flare tool.

[Master-O-Turbonics]

I bought a blue point double flaring tool off the tool truck for under $60. dont skimp on the most important safety system on your car