Bench bleeding master

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Good morning! I've done many searches on this topic but couldn't find my exact issue. Replaced master with OEM master on my 78 FJ40. Also replaced front hoses and calipers. Trying to bench bleed the master while bolted on the rig. The rear reservoir will push/pull fluid as expected, but can't get the front res. to do anything. I opened up the fitting on the side of the master and fluid pours out but doesn't purge any air. Needless to say, I can't get any fluid down to my calipers. Am I missing a step? Thanks!!
 

Dynosoar

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Bench bleeding is done on the bench not in the truck. You results will not be the same doing it in the truck. You most likely need to adjust your booster push rod.
Dyno
 
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Your mounted cylinder on the vehicle can be the "bench". The output of the cylinder needs a fitting to run back into the reservoir. Here is a video that shows how to do it.

 
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Your mounted cylinder on the vehicle can be the "bench". The output of the cylinder needs a fitting to run back into the reservoir. Here is a video that shows how to do it.

Thanks for the video. I’m aware of the bleeding procedure and have tried it a few times already. My issue is there is no fluid moving in the front reservoir. I either need to make the rod length adjustment or I have a bad master is what I’m thinking.
 
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removed master and attempted to bench bleed on bench. Still no action in the front resivoir. This tells me the push rod isnt the problem because I can bottom out the valve in the master and still no fluid from front. I'm guessing I have a bad master out of the box.
 
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removed master and attempted to bench bleed on bench. Still no action in the front resivoir. This tells me the push rod isnt the problem because I can bottom out the valve in the master and still no fluid from front. I'm guessing I have a bad master out of the box.

Probably. There is probably something wrong in the one system where no fluid is being pushed. Where did you buy the Master ?

Brake master.PNG
 
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I really do not know that bolt function. Perhaps used at the rebuilder for some reason. In your case if it is not leaking there is an internal issue.
 

Mtntopper

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It was the one listed as OEM at Cruiser corps. Can you tell me what this bolt does if anything? View attachment 2677108
Hard to tell from their website if that master is new or rebuilt, for that price I would expect it to be new. I had two rebuilt masters in a row that had a binding piston inside. I finally installed a new master with an Aisin part number and there hasn't been an issue since.
 

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