Why I DISLIKE DOT 3 Brake Fluid

[Richard M.]

My wife's car sat for over a year while working on several Corvettes. Waiting for me to rebuild the SU electric fuel pump(bad points), 4 Zenith Carburetors(red debris, torn diaphragms, etc), and a leaky brake fluid bottle and just discovered leaking master cylinder rear seal.

I would have liked to use Silicone DOT 5 fluid 15 years ago when I finished restoring the car, but Lockheed then stated their seals were not compatible, which I should have ignored. The DOT 3 Paint Remover did a good job.

Keep a close eye UNDER your Corvette firewall interior below the Master Cylinder and its Dust Boot for signs of leakage and a close eye at fluid levels in the MC. I had the fortune of seeing the brake fluid bottle level low as a sign after the car sat for a long time. Thankfully the brakes still worked fine, but were about to create a potential disaster while my wife, my Best Customer, may have been driving her car.

[John D.]

Re: Why I DISLIKE DOT 3 Brake Fluid

Nice Car Richard, My brother and I owned two XKE's. I think they were 74's. Those car specialized in leaking all over the garage floor as I recall. Worse than a SB Chevy or my Model A Ford 4 cylinder. JD

[Gene M.]

Re: Why I DISLIKE DOT 3 Brake Fluid

Are not British cars supposed to leak everything? Looks like a nice candidate for resto mod chevy drive train, Tremec 5 speed, and Willwood brakes. Sorry I couldn't help myself..........

[Richard M.]

Re: Why I DISLIKE DOT 3 Brake Fluid

LOL Gene, not a chance. If I put a LS3 in it, according to the "Dark Side" Restomod Corvette guys I know, who have seen this car, tell me that she'd loose total driving control if it did, plus she'd probably beat my '59 Corvette off the line. The V12 looks cool, but really a dog at just under 300hp through 326ci. At 150+mph it's quite smooth though and talks to you for more.

And yes to both you and John, If a Jaguar or old British car doesn't leak oil or fluid, it means there's no oil or fluid in it. Obviously, brake fluid included.

Check those Master Cylinders.

[Jim D.]

Re: Why I DISLIKE DOT 3 Brake Fluid

If a Jaguar or old British car doesn't leak oil or fluid, it means there's no oil or fluid in it.

No truer words have ever been printed. We won't even address "The Prince of Darkness".

[Richard M.]

Re: Why I DISLIKE DOT 3 Brake Fluid

My back and neck hurts. When I'm done with this project I can't wait to get back to a simpler Corvette project, like the 61 fuelie I have here to finish build-up after paint. I love the simple C1's. So much more fun. Her jags keeps me in complexity practice.....13 parts on something that really only needs 3. And Lucas electrics aren't bad.....they're terrible.

[Ed H.]

Re: Why I DISLIKE DOT 3 Brake Fluid

I just had the DOT 3, 4, 5 discussion last week. The party, who's in the business of restoration work, currently has an XK-120 in process, said that he had really bad results (leaks) using DOT 5 in British cars. Of course, as has already been said, if it doesn't leak... The entirety of the brake syste in my car is being replaced, and we plan to use DOT 5.

[Richard M.]

Re: Why I DISLIKE DOT 3 Brake Fluid

Ed, I really wish I had used Silicone when I restored the car. I had all brake parts removed and would have been a ideal time to switch over. You should be fine using it on that XK120.

new interesting find..... We've owned this car 25 years and I never had the brake lamp switch out of it's bracket before. It's housing popped off when I tightened the pedal box bolt nearby, thinking i broke it I was unhappy, however, it's made to come apart, so a good time to clean it. It's repairable. It's a original C30137 Jaguar part # switch, but it's Delco Remy. There are many GM parts on Jaguars, A6 AC Compressor, GM A.I.R Pumps and valves, etc. The switch is GM based too.

Note where it was made. I did not know Delco Remy had a manufacturing facility in England then.

[Ed H.]

Re: Why I DISLIKE DOT 3 Brake Fluid

OMG, this isn't mine...



Relatively recently. It now has rear fenders, doors, and the all important 'Bonnet'.



How it arrived.



This is mine.

The man has done a lot of cars, and if he won't use DOT 5 in things British, well I'm not going to argue.

[Domenic T.]

Re: Why I DISLIKE DOT 3 Brake Fluid

I have a sad dot 3 story.
Back in the 70's I was working part time in a exotic car business. A sneaky independent car salesman came in for work on a Rolls. His gig was advertising in the paper that he could sell your rolls, then he would tell the seller that he had a potential buyer and that he needed to keep the car for a while. He would then drive the car to another Rolls owner and say it was his to gain there trust.
Those Brit cars used Gurlling brake fluid and had a hydraulic pump for the brakes, leveling shocks, and power steering. The fluid was low and he decided to put dot 3 in it. The dot 3 will eat the seals up and it leaked more, so he kept adding more in till all the shocks, Hydraulic pump, brakes, and power steering pump went out. He called me at home and asked me what I thought was wrong because the more he added fluid the worse it got. It was then a death trap and he told the owner to have the car towed back and that it would need work before he could sell it. He never told the owner what he did. But he did get another Rolls to drive & sell while he had that Rolls.

Dom

[Joel M.]

Re: Why I DISLIKE DOT 3 Brake Fluid

That Jaguar FHC looked far worse when the restorer acquired it. It had neither rear springs or rear end and no front wheels. Truly amazing.

[Ed H.]

Re: Why I DISLIKE DOT 3 Brake Fluid

That Jaguar FHC looked far worse when the restorer acquired it. It had neither rear springs or rear end and no front wheels. Truly amazing.

LOL, do I detect inside knowledge?





Sorry for the thread drift!

[Richard M.]

Re: Why I DISLIKE DOT 3 Brake Fluid

Ed, It's all good, No Drift, all applicable...... Cool photos. See, even dead Jaguars with no engines or brakes leak stuff too. Nice job they're doing. Sorry, I thought it was yours.

Your Corvette chassis looks great !! (to be keeping on Corvette topic)

Domenic, interesting story. Wow.

So I got the MC installed and brakes bled, all is good. No leakeys. Nice hard pedal. I have a funny story for morning coffee about the owner helping me bleed the brakes.

4 carbs back on tonight and ready to run, but it'll have to wait, as tomorrow I have to install Hurricane Shutters on the house/shop and battening down the hatches for later this week. Darn Mathew.....

Rich ps BTW, for the curious...
FHC = Fixed Head Coupe (a coupe, no folding top) like above
DHC= Drop Head Coupe (a coupe, with windscreen side frame pillars just like the FHC, but with folding top)
OTS = Open Two Seater (a convertible, unique small frame windscreen, with folding top)
COUPE = coupe
2+2 = Like coupe subject car, 2 seats front, 2 seats rear(for small humans only or one medium human sitting sideways, no big humans)

See, even the names are too complex.

[Edward B.]

Re: Why I DISLIKE DOT 3 Brake Fluid

My parent's driveway in 1963. Unfortunately, the XK-140 was replaced by an E-Type Roadster. The XK-140 was the most reliable of the bunch, not that that is saying much.

[Joe R.]

Re: Why I DISLIKE DOT 3 Brake Fluid

Cool pic!!!