Author Topic: Brake Line Routing  (Read 1555 times)

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Offline Dilkris

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Brake Line Routing
« on: Saturday,March 21, 2020, 07:48:38 AM »
Can somebody please direct me to a link describing the brake line routing for a twin cam? A diagram, sketch or collection of photo's would be ideal.   

Offline BDA

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Re: Brake Line Routing
« Reply #1 on: Saturday,March 21, 2020, 08:15:35 AM »
The parts manual is a good guide (http://www.lotus-europa.com/manuals/tcparts/j/tcjb.pdf). Basically, if you are using boosters, you run both front and rear lines to rear to connect with the boosters and the PDWV. Then run the front line back to the front and to the brakes and rear lines to the brakes. If you don't use boosters, you could move the PDWV to the front and simply run the front to the front brakes and the rear to the rear brakes.

Does that help?

Offline SilverBeast

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Re: Brake Line Routing
« Reply #2 on: Saturday,March 21, 2020, 09:40:00 AM »
If it's a UK Twin Cam or Special it will have single circuit brakes and a single Servo (still at the rear). The manual extract linked above is for Dual Circuit brakes. I don't think it has the PDWV (Pressure Difference Warning Valve) either.
« Last Edit: Saturday,March 21, 2020, 09:41:43 AM by SilverBeast »

Offline EuropaTC

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Re: Brake Line Routing
« Reply #3 on: Saturday,March 21, 2020, 10:08:36 AM »
If it's a UK spec TC with single circuit plus servo then.....

Out of the master cylinder, turn left (RHD) and through a hole in the front of the T section on the chassis. Tubing goes down inside the central spine to the rear, exits through the closing plate just in front of the Y split and goes inside the chassis leg to the servo.

Out from the servo and down to a multi-way connection on the chassis leg. On mine this was a 5-way junction as follows;

1. Inlet from servo
2. Brake light switch
3. front brakes
4. RH rear brake
5. LH rear brake.

The front brake line goes back through the central spine and out the front where it splits into a 3 way connection mounted on the chassis with one for each front caliper.
The rear lines go along the chassis legs and to the flexible hoses on the suspension arms, then short lengths along the arms to the rear drums.

I don't think there's a good diagram, the S2 manual shows the arrangement as does the parts lists for all models. I'd say the S2 is the best you'll get unless someone has gone to the trouble of drawing it out.

Brian


Offline BDA

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Re: Brake Line Routing
« Reply #4 on: Saturday,March 21, 2020, 10:23:23 AM »
Aakk!! I missed his location! I'm glad Brian & SilverBeast were paying attention!

Offline SilverBeast

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Re: Brake Line Routing
« Reply #5 on: Saturday,March 21, 2020, 10:57:44 AM »

Here's a shot from the front underneath of mine with the chassis closing plate off (wasn't fitted when I got it - new one in the rear luggage tray waiting to be fitted.

You can see where the line from the master cylinder to the servo goes through the T on the chassis (I believe it passes through the leg of the tee and out the back - not into the central backbone "tunnel").  You can just see (on my original at least - we'll see when it's posted!) where it exits the back of the tee and is clipped on the underside of the central backbone of the chassis on the passenger side (right in picture), along with the servo return to operate the front brakes.  The return also passes through the T and exits on the right of the shot and heads up to the 3-way junction Brian mentions above.  Sorry I haven't got any shots at the rear at the moment.  There may be some and/or some discussions of the routings on Certified's restoration thread here->http://www.lotuseuropa.org/LotusForum/index.php?topic=1704.0.  Obviously his car is US spec though

Offline Dilkris

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Re: Brake Line Routing
« Reply #6 on: Monday,March 23, 2020, 01:41:02 AM »
Thankyou BDA, Silverbeast and Europa TC. you have given me enough data and links here to move forward. ("Yes" -  I should have said it was a UK car devoid of dual circuits - my omission.)
Silverbeast - just a minor observation, your drop link is located to the wrong side of the anti roll bar "indent" is it not??   

Offline SilverBeast

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Re: Brake Line Routing
« Reply #7 on: Saturday,April 04, 2020, 02:22:52 AM »
Silverbeast - just a minor observation, your drop link is located to the wrong side of the anti roll bar "indent" is it not??   

Sorry. Just seen this. Yes you are correct. It was like that when I bought it last year. If was one odd the first questions I asked on the forum. I've only done about 100 miles in it since I got it. I started checking it out in more detail and discovered some wheel nuts/ studs stripped when I tried to torque them top the correct level.  It's still waiting to be fixed along with other issues due to lack of working space in the garage and the weather and other excuses.