Brake booster won't start

Cougar Community Classic Cougar Maintenance Restoration and Repair
1

Hey everyone I got myself into a mess. I had a nice running 68 cat with a new crate 351w and AOD installed. ran it for about 500 miles and the brake master cylinder and booster decided to start leaking. I know should have done them with the motor out anyways :wall:

Installation wasn’t too bad, a couple socket extensions and wobbler made quick work after finally getting the right parts, btw napa’s listings are wrong.

The problem is I finished bleeding the rear brakes, pulled the car back about 5 feet to have more room to bleed the front brakes. Car started fine moved it spilt a little brake fluid in the process, lid wasn’t on properly. turned the car off, bleed the front brakes. went to go for a quick test drive and couldn’t start the car.

This was a few days ago and at first I thought maybe I had flooded it, checked spark good, getting fuel, check.
I even brought a local mechanic over to check it out and he is currently thinking about what it could possibly be. It is as if the car fires and looses power.

Basically the car turns over, fires but as soon as I let go of the key it dies. Any help would be greatly appreciated, thanks


Its got new pertronix distributor and coil. edelbrock 1406

2

I dont think the booster or a small fluid spill caused the problem. I would check the ignition switch and make sure there is power in the run position. You could also hot wire the car from battery to coil and jump the solonid that way you are powering the ignition if the car starts and runs you eliminate a bad coil or distributor issue. you can also check to see if you loosened any connections coming thru the firewall while changing the booster or under the dash while disconnecting the brake switch.

3

Thanks for the ideas.
The mechanic tested to make sure there was power to the coil with the ignition key in and in the run position, didn’t check voltage but the test light showed power.
I am not sure about hot wiring the car but he did do something with the starter solenoid causing the car to crank over without me turning the key with no success.

Are there any specific wires that I could have loosened while changing the booster. I have looked under there are few times and haven’t noticed anything but am thinking that it might be something I just am not seeing down there.

4

Could it be a loose engine ground?

5

Sounds like you some how unhooked the wire to the tach under the dash. make sure the tach wire is connected.

6

Not sure this would keep it from starting, but did you forget to reconnect the vacuum line to the booster?

7

Thanks for the response, I have tried with the vacuum line attached to the booster and also plugged just in case it was something with the booster.

8

2nd that one

9

Or the tach died because the new coil is lower in resistance and is pulling more current through the tach than it was designed to handle. Run a jumper wire to the coil positive and see if it will stay running.

10

I will check a few of the engine grounds and make sure. thanks

The tach wire would make sense but it is a standard so I don’t have a tach.

Would I still have the same wires?

Thanks for all the ideas everyone.

11

Keep plugging away at it and keep us informed. Hope you get it fixed soon.

12

Did you check the pertronix , they are great units but it could be defective. When the mechanic jumped the solonid the car will crank as it did but unless he powered the coil the car wont start. by running a wire to the coil from the pos side of the battery you are bringing direct power to the coil. at that point you are not using the cars wiring or ignition switch. so if you still have a no run condition your problem is most likley the distributor or coil.If you have the old distributor you can put that in and see what happens. a lot of time new parts are overlooked as the cause of a problem.
Good Luck

13

Did you remember to put the ground wire inside the distributor back when you installed the Pertronix?

14

Running 9V or 12V to Pertronix? Pedapter kit may be needed here…(speaking from experience)

http://www.rccinnovations.com/index.php?show=menu-relays

15

You guys are great, thanks. I got to go to work today but when I get home I will check my distributor ground wire and try powering the coil directly.
I didn’t check the voltage going to the pertronix, assumed it was because I used the same wire as the last one I had in there from the previous motor, but will get the meter out a check…

thank for the great ideas guys, hopefully I can get it going again after work.

16

So I had some time tonight and I checked the distributor ground with a test light, it was grounded.
I also checked a few of the engine ground wires but attaching the test light to them and touching the battery, the light turned on.

I checked the power wire to the powering the coil with the voltage meter, with the key turned it read just under 12v. I them ran a wire straight from the battery to the coil and it read just over 12v. everything I tried had the same results. cranks fires but won’t run.

I am thinking that this is a good thing, nothing changed from the wiring back from the coil so all problems are after the coil?? possible distributor, coil, maybe even carb…

Thanks again for all the ideas and advise, tomorrow I will do some more checking

17

if your getting fuel to the carb and when you hit the throttle fuel is comming out of the squirters in the carb the car should at least run. So it sounds like a coil or distributor issue. You said it was a new engine, you can also check the timing just in case the distributor moved while you were driving. another thought does the car have a roller cam (later 5.8 had them) or a regular cam. You cannot run a regular gear on the distributor if you have a roller cam or a roller gear with a regular cam, the gear will get torn up.

18

Another ugly possibility is that the timing chain jumped a few teeth when you shut the car off.

19

I think at this point re-installing the points, condenser, and original coil might be worth the effort. I’m not sure but does the Pertrx have a start up dwell?

20

I pulled the distributor yesterday and took a look at the gears thinking that maybe some how it was the wrong gear, it sheared the pin or destroyed the gear and it looked new still. it is a none roller cam.

Can I check the timing just by cranking the motor over with the started without it running?

I am really hoping that it is not a jumped timing chain. I know it is a new True Roller double timing set, according to the engine manufacture.

I really am wishing I had the old points distributor but the original motor was a 289 so my old distributor won’t fit. I am thinking I might try and find or borrow one just to check the issue.

Hopefully after work I can make some more progress. Thanks guys