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Discussion Starter #1
Was just able to loosen my MC cap with a strap wrench to find I am down a lil over an inch below the top.........my question is; what brake fluid do I add? I do not know what the PO had in there so is there a way to check? I cannot bleed my own at this point.will it be necessary to have them bled someplace & new fluid put in? Thanks in advance. John
 

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Most likely you have DOT3/DOT4 fluid in your system. As the brakes wear, the fluid level in the reservoir will gradually fall, especially in a disc brake system. Since it sounds like you have the "jelly Jar" master cylinder and a screw on cap, you should have a drum brake system. I would not fill the reservoir closer than 1/2 from the top. You may want to monitor the level closely and check all the lines and wheel cylinders for seepage. Also inspect the seal inside the cap for deterioration.
 
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I figured it was DOT3/DOT4....but thought there was another possibility...............Am I running any risk by adding that? Thanks
 

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Well, the other possibility is DOT5, but converting to or from DOT5 would require a complete flush of the brake system. I suppose the scientific approach would be to remove a small sample from the reservoir, add a drop of water and mix thoroughly. If the water is absorbed, it is not DOT5; if the water sinks to the bottom of the testtube it is DOT5.
 
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Thanks.......will try that tomorrow.........BTW.......will be up your way in September for the Tunbridge World's Fair...never miss it.......Thanks again.....John
 
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Top it off with dot 3 and when you get a chance check the brakes. Inspect the wheel cylinders for seepage and the brake shoes for ware if below 3/32 its a good idea to replace the shoes. If you have no brake pulsation you can hand surface the drums with some sand paper best is to have turned at a shop. The low fluid could be just to normal brake lining wear.
 

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Watch out for the drunks, they pass out in the ditches along the parking areas.
 

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Dot 3 or 4 will be ok.. no silicone based stuff. The bleeding should not be needed as long as the MC holes in the based were not exposed. Fill it, pump it up, proceed with caution at first. It's always a good idea to flush out your system completely once and awhile, now may be a good time, while you're at it.
Brake fluid is funny stuff, it will destroy paint and metal, but washes up easily with water!!
 
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