FJ40 (1966)brake bleeding problem (1 Viewer)

Joined
Sep 21, 2014
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7
I just purchased my 5th FJ40, it is a basket case but I knew that going in.My main problem now is the brakes. When I got it the brakes would pump up but not hold pressure. I checked all wheels (new brakes in front) (following CoolCrusiers recommendation) I adjusted all wheels. There are no leaks in the system, all wheel cylinders are dry. At this point figured the Master cylinder must be bad. Bought and installed a new MC (Ebay-Centric special). Tried to bleed air out of system after running 1.5 quarts of new brake fluid through system still getting bubbles and have the same problem as with the old master cylinder. Brakes will pump up solid and if you hold the pedal down it will hold but as soon as you let up on pedal the brakes go to zero. At this point I connected my vacuum pump to the output of the new Ebay special MC and got a steady fluid and air buibbles. My problems is I suspect the new MC is bad butt it appears to be the same problem as the old MC, where am I going wrong?
 
Joined
Sep 21, 2014
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Yes and yes
I have bit the bullet and ordered a MC from CoolCrusier they are twice as expensive as the Ebay special so I hope I have better luck?
 
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May 8, 2014
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Wilmington, N.C.
Yes and yes
I have bit the bullet and ordered a MC from CoolCrusier they are twice as expensive as the Ebay special so I hope I have better luck?
I had the same problem with my 66 even after replacing all lines. I would suggest: bench bleeding the master, tefloning the fitting on the line from the MC, and checking your pedal /piston adjustments=particularly the latter if you went from OEM MC to repop. Because of me or in spite of me, one of these solved my problem. Good luck
 

JohnnyC

Long ago TLCA# 2231
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Jun 17, 2005
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UpState Ny, Wells Me
Are you getting fluid from all cylinders?

I know a few guys were having issues that they couldn't get all the air out it seemed... They had not a nice time with the ccot wheel cylinders ... I'll see if I can find the past post with good info in it

Did you bench bleed the mc?

Single line mc?
 
Joined
Apr 6, 2011
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Location
Defiance Missouri
Check the rod adjustment from the fire wall into you master there round nut on the end of it which adjusts. If it is out to far you will get great brakes but as you drive pressure will build and you will lock them up. If it is not out far enough the master will not push enough fluid to fill the brake cylinders. It has to be adjusted just so it is touching the inside of the master but no farther or pressure will build. I have the ebay centric master also and it took me a long time to get it adjusted correctly originally thought it was a brake bleeding issue.
 
Joined
Sep 21, 2014
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7
I have brakes!!!!!!
Received and installed new MC (the second one) made several passes at bleeding with no results.
Having read a comment by "PinHead" (kudo's to PinHead) I drug my faithful assistant out to the shop to bleed the brakes the old fashion way, pump the pedal, crack the spigot, pump pump ... etc.. After making two passes at bleeding all wheels I had over half a pedal and solid brakes.
Conclusion: The Harbor Freight one man vacuum pump will not bleed FJ40 brakes. This lesson cost me three days of unnecessary brake bleeding and $100 for a MC tha I probably did not need.
 
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Feb 6, 2002
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OC, CA
I'm glad it worked out great for you. A lot of people just don't appreciate how poorly the "one person" things work.
I worked in an 8 bay shop that did an average of 8-10 brake jobs a day and we always used two mechanics because it was the quickest and most fool proof way to get the job done.

It also helped that two mechanics could testify that the brakes were fine when the car left the shop in case they got sued.

PS: I have never seen a brake cylinder or caliper that needed to be "burped" in thousands of brake jobs I did in my short career as a high volume mechanic.
 
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Joined
Sep 21, 2014
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I am not sure what "burping" is. But I suspect the difficulty with the FJ40 brakes is the wheel cylinders being mounted ventricle where air is getting trapped in the down side. I have used this One Man on my 57 Ranchero and had no problems. On the FJ40 you are dealing with only one wheel cylinder at a time so the only difference is the mounting.
I will definitely agree with you using two men to bleed a system is the fastest and easiest.
 

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