Bleeding Brakes

[jbcollier]

Advice in order of preference:

1)  Remove the boosters and fit a smaller master cylinder: same pedal effort, slightly longer travel.  This greatly simplifies the brake system and makes bleeding a breeze.  Moderately easy job for the amateur mechanic.  Remember, TC/S came with an un-boosted, SINGLE circuit brake system in the UK so the boosters are not needed.

2)  Fit new boosters.  Functions identically to the originals but they look different if you are worried about originality.  Would recommend professional pressure bleeding if you are inexperienced.

3)  Rebuild the old boosters professionally.  There are a number of places that do the work.  It ain't cheap as most hydraulic cylinders have to be sleeved due to wear.  Otherwise same as #2.

4)  Rebuild the old boosters yourself:  This is just plain DUMB if you are not an experienced mechanic.  Would you even know what a worn cylinder looks like?  Would you know if they were working properly when you were done?  I have 35 years as a mechanic and I have simply stopped rebuilding hydraulics.  Sure, most of them turn out well, but most is not all.  I want my brake work to be safe, reliable and problem free.  That means fitting new hydraulic parts wherever possible.

I have rebuilt several boosters, all successfully but one in particular illustrates my concerns.  Someone had previously overhauled the booster and the owner was complaining about poor brake performance.  When you pushed on the pedal, it actually moved up, not down!  I stripped it and found they had installed a vacuum shuttle valve backwards.  It fit both ways so there was no visual indication it was assembled incorrectly.  So please do not take door number 4!

[Europa73]

I am in the process of restoring my boosters.

I found a fantastic place in the US - they can provide the entire kit or parts.

Great service and very knowledgeable over the phone.

the company is - Harmon Classic Brakes

www.harmonclassicbrakes.com

[BDA]

There are several Girling booster rebuild kits listed on ebay and I suspect they were used in other Brit cars so you might also be able to get them at a place like Moss Motors. You can sometimes find complete  boosters listed on ebay. Unfortunately, I don't know the exact model booster so you'd have to do a bit of research to find out which one you need.


A last resort would be a restoration shop. White Post Restorations (whitepost.com) seems like for the right money, they could rebuild any brake component. In fact, they sleeve cylinders with with bronze or copper which should greatly enhance the life of them. I've used them and they are good and quick. I'm sure there are others.

[FranV8]

JBC - my TCS has a single circuit set up and a single booster, as it left the factory.  The Tamiya model also features one!  I've cheated and bought the equivalent Lockheed replacement to fit though.

That could be an option, although the Lockheeds are bigger and the fittings in different places, fit two Lockheeds on the dual circuit cars?

[tedtaylor]

Bruce, when you finish rebuilding yours, i'll need to get the latest information on where you got the rebuild kits because i'll be doing both my boosters in my new JPS pretty soon.

[Europa73]

Just finished restoring both mine tonight.

Will be fitting them tomorrow.

[brucelotus26r]

Yesterday I removed the brake boosters and made two jumper brake lines.
After bleeding the left side brakes I had a rock hard brake pedal,I took the car for a drive down to Certified Lotus /Glen's.
The brakes worked good but the pedal is way to hard.  I'm thinking about replacing the Europa .875 master with the smaller .70 master from a later Spitfire. "Simplify and add lightness"  :/beerchug: Glen put some pictures of my car on his page.

[tedtaylor]

I should have offered you my temporary "jumpers" I made when I did the same thing (while booster were out getting rebuilt).   Same experience with rock hard pedal, but high effort needed to stop.   Opted to rebuild the boosters and have never looked back...

[EuropaTC]

Yesterday I removed the brake boosters and made two jumper brake lines.
After bleeding the left side brakes I had a rock hard brake pedal,I took the car for a drive down to Certified Lotus /Glen's.
The brakes worked good but the pedal is way to hard.  I'm thinking about replacing the Europa .875 master with the smaller .70 master from a later Spitfire. "Simplify and add lightness"  :/beerchug: Glen put some pictures of my car on his page.

I've used the 0.7" master and currently have a 0.75" one fitted which I think gives shorter travel without too much effort.  Before swapping cylinders you could try alternative front pads with a better "bite" from cold. I've used both EBC Greenstuff and Mintex 1144; I think overall I prefer the Mintex. 

Brian

Edit to add...   it's just dawned on me that you're the guy with the red TC and interesting exhaust manifold shown on Certified Lotus's thread.  So I'll ask directly - is that a 4-2-1 or 4-1 system ? My interest is that I want to make one and with almost zero experience I'm reading up and looking what others have done.

[brucelotus26r]

4-2-1 The 4 primary are all 17" going into 2 just in front of the shifter u-joint and going into 1 under the starter turning up to the muffler run over the axle along the trans.

[EuropaTC]

Thank you Bruce, that's very useful info, especially about where the joins are located.   I've been playing about with 13" lengths of wire and struggling to get an equal fit within th ebounds of sensible bends so I'll try longer sections today. 

Thanks again, it's very helpful.

Brian

[4129R]

I have a new MC, new servo, new brake lines and had a dry system.

Having filled up the MC, I have fluid both sides of the MC connections, but 50 pumps on the pedal hardly lowers the fluid level in the MC.

I have tried another new MC, no difference.

I have by-passed the new servo, no difference.

If feels like there is no fluid being pushed by the MC or an air lock in the MC, even though I filled up both bores of the MC before fitting it to the chassis.

When I by-passed the servo, fluid did leak from the servo, so I know a little is being pumped.

This is the 6th car I have re-built, and I had no problems with the first 5. 50 pumps on the pedal would have 1/3 emptied the MC, but not this time.

Any suggestions?

I have ordered a reservoir pressurising kit from Machine Mart due late next week. In the meantime, has anyone else had this problem or any ideas on what is wrong, and how to solve it?

[Kendo]

4129R, is this a single or dual circuit system? If dual, could you have tripped the PDWV valve? (And, would that cause this symptom?)

[4129R]

Single circuit. Very simple system. All new and empty of fluid.

I just wonder if the MC being dry for a long time might not be sealing properly.

But I have tried two new MCs, both bought long ago from Banks. 0.75, single circuit, remote header reservoir. .

Do they have a dry shelf life?

[BDA]

The only thing I can think of is to suggest that you bench bleed the M/C but I suspect you’ve already done that.

Two other things I might do, although I don’t think it would fix the problem but might give me some insight, would be to use a pressure bleeder and to disconnect the lines at the M/C and see if you can get fluid to pump out and if so, try the same thing further down until you either get to the cylinders or calipers or you find the problem. I’d probably do that as much out of frustration and curiosity as anything. On second thought, I might not use the pressure bleeder because it might mask the problem.