moper
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That's your hard pedal.
1978 NYB New Engine.....
- Thread starter 1978 NYB
- Start date
That's your hard pedal.
rags
Senior Member
depending on the converter stall speed, thinking that on the road during a closed throttle coast the vacuum would be a lot higher and the vacuum can would retain it.
Before I installed the vacuum canister I had one good pump of the power brakes. Hitting the brakes a 2nd time produced the hard brake pedal. After installing the vacuum canister I have a hard brake pedal on the first pump.
B&M 2400 stall converter.
The instructions said to run it 1200-1500 rpm's for a minute after startup and the vacuum supply should be adequate.
65sporty
Old Man with a Hat
After the can was installed and you got the hard pedal did you check the vacuum at the booster again?
rags
Senior Member
it's just too much volume to evacuate or the check valve on the can's no good.
65sporty
Old Man with a Hat
Bob, do you have the hose from the engine attached to the can's check valve and the nipple from the can attached to the boosters check valve?
Yes
I have a check valve on the booster with 3 hoses on it. I have a plain single new check valve for the booster. I'll see if that does it.
Yes, plenty of vacuum at the booster.
If I can't get it to work I might have to eliminate the canister and see if the brake pedal is back to normal.
twostick
Senior Member
14.5 isn't ideal but it should have power assist at that. If you see zero assist I'd pull the fitting out of the booster to see if the check valve still functions. If you can blow thru the end that the hose goes to, it's FUBAR and probably your problem. If it's OK, the booster is probably the shot.
Kevin
Kevin
I'll be working on it Saturday and I'll let you know what the results are.
commando1
Old Man with a Hat
14.5 should be fine. I don't think you need a cannister.
Like I said at the beginning of the brake booster situation. Before the canister install I had one good pump on the pedal. The 2nd pump was rock hard. After the canister install it was a hard pedal on the 1st pump. Something just doesn't make sense. I'm going to eliminate the secondary vacuum lines from the booster ( cruise control and the rear air ride suspension) and see if that changes anything.
twostick
Senior Member
The air pressure is built off an auxillary vacuum pump hidden in the left side fender well. There is an additional vacuum line running from the brake booster to that vacuum pump in the fenderwell.
Got the A/C hose back from Benz Hydraulics from Bear, Delaware.They ordered the fitting I needed, shipped it UPS, mounted the fitting to the hose in 24 hours and cost a grand total of $39. One of the only reasonable expenditures on this journey so far. I'm way past $16k on this engine build so far.
commando1
Old Man with a Hat
You'll have a one-of-a-kind NYB. It will be worth it.
38° ambient temp and she started right up with no battery or fuel aids.
I thought that was quite impressive.
I thought that was quite impressive.
