Datsun 521 Project

[mklotz70]

Too much travel and having to pump is adjustment.....shoes aren't close enough to the drums.

Spongy is typically air, but can be old rubber hoses or new shoes/parts that aren't "bedded" in yet.

[MikeRL411]

7 hours ago, mklotz70 said:

Too much travel and having to pump is adjustment.....shoes aren't close enough to the drums.

Spongy is typically air, but can be old rubber hoses or new shoes/parts that aren't "bedded" in yet.

 

As I have said before, replacement shoes are oversized.  You machine the drums on a  proper drum lathe then machine the shoes to match the radius of the newly machined drums.  No "bedding" required if properly machined and bled.

 

 

[njp.18]

20 hours ago, thisismatt said:

Did you readjust the brakes?

the only brakes I re-adjusted was the rear passenger side since that was the only one side i had loosened the adjuster wheel on when putting it's brake shoes back on.

[njp.18]

11 hours ago, mklotz70 said:

Too much travel and having to pump is adjustment.....shoes aren't close enough to the drums.

Spongy is typically air, but can be old rubber hoses or new shoes/parts that aren't "bedded" in yet.

Ok, ill adjust the brakes closer together on the wheel i did the bearing on some more. I assume I shouldnt have to adjust the others since I didnt touch them. If no improvement, ill bleed them some more. thanks

[datzenmike]

Adjust ALL the brakes, front and rear. The 521 has a single master cylinder that has to move all the brake cylinders. A lot of pedal travel is wasted moving the shoes towards the drums and they only get farther away as they wear down. For optimum breaking they should be checked and adjusted at least twice a year.

 

Spin wheel by hand and adjust till rubbing. Apply brake several times to center the adjuster and  check and adjust again if needed.

 

When done, adjust the emergency brake.

[njp.18]

1 hour ago, datzenmike said:

Adjust ALL the brakes, front and rear. The 521 has a single master cylinder that has to move all the brake cylinders. A lot of pedal travel is wasted moving the shoes towards the drums and they only get farther away as they wear down. For optimum breaking they should be checked and adjusted at least twice a year.

 

Spin wheel by hand and adjust till rubbing. Apply brake several times to center the adjuster and  check and adjust again if needed.

 

When done, adjust the emergency brake.

got it thanks

[mklotz70]

21 hours ago, MikeRL411 said:

 

As I have said before, replacement shoes are oversized.  You machine the drums on a  proper drum lathe then machine the shoes to match the radius of the newly machined drums.  No "bedding" required if properly machined and bled.

 

 

That's the way they should be done, but I only knew of one place that would grind the shoes down to fit correctly and they went out of business long ago.  My understanding is that the "bedding"....at least with pads, is to "cook" the material together.  Maybe shoes don't need that?

[datzenmike]

I had problems replacing shoes on my B-210 back in the '70s. No way they fit so ground down the contact points on the shoes at the wheel cylinders and the adjusters to get them on. (I know more now) Shoes worked fine but they got better as the wore down the high spots to exactly match the drums.

[njp.18]

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Edited May 6, 2022 by njp.18

[njp.18]

Are you guys aware of any typical problem that causes the fuse circled to keep blowing. It blows and then my fuel gauge, turn signals, coolant temp, ext. dont work. I dont see any split wires grounding out under the dash or near the fuse box.

Edited May 6, 2022 by njp.18

[njp.18]

On 5/1/2022 at 1:41 PM, datzenmike said:

Adjust ALL the brakes, front and rear. The 521 has a single master cylinder that has to move all the brake cylinders. A lot of pedal travel is wasted moving the shoes towards the drums and they only get farther away as they wear down. For optimum breaking they should be checked and adjusted at least twice a year.

 

Spin wheel by hand and adjust till rubbing. Apply brake several times to center the adjuster and  check and adjust again if needed.

 

When done, adjust the emergency brake.

I adjusted the brakes and it didnt do too much in regards to my problem of the pedal going to the floor and having to pump. I then tightened up my e-brake cable because there was too much travel and that fixed both problems

Edited May 6, 2022 by njp.18

[datzenmike]

8 minutes ago, njp.18 said:

Are you guys aware of any typical problem that causes the fuse circled to keep blowing. It blows and then my fuel gauge, turn signals, coolant temp, ext. dont work. I dont see any split wires grounding out under the dash or near the fuse box.

 

http://i258.photobucket.com/albums/hh275/Daniel_521/Pinout.jpg

 

  Just the ignition switch turned on and the fuse blows? Reach up behind the instrument cluster and pull the 10 pin connector loose and try. This eliminates anything to do with the instrument cluster.

[njp.18]

18 minutes ago, datzenmike said:

 

http://i258.photobucket.com/albums/hh275/Daniel_521/Pinout.jpg

 

  Just the ignition switch turned on and the fuse blows? Reach up behind the instrument cluster and pull the 10 pin connector loose and try. This eliminates anything to do with the instrument cluster.

no it doesnt blow right away. it blew last week for the first time while driving,so i swapped the fuse and took it for a test drive and it blew about 10minutes in to the drive so i swapped in another fuse last week and it was fine until it blew again today.

[datzenmike]

See if it's the wrong fuse. Oh, I see it's obviously 10

 

Do you have a high output alternator or the stock 35amp?

 

Is your voltage regulator over charging? Should be just over 14v when revved up but if it spikes to say 15 it will push more current through the fuse and may be enough to blow it.

[njp.18]

1 hour ago, datzenmike said:

See if it's the wrong fuse. Oh, I see it's obviously 10

 

Do you have a high output alternator or the stock 35amp?

 

Is your voltage regulator over charging? Should be just over 14v when revved up but if it spikes to say 15 it will push more current through the fuse and may be enough to blow it.

I dont have the stock alternator or voltage regulator. I have a one wire alternator swap

Edited May 6, 2022 by njp.18

[datzenmike]

The stock alternators didn't make much power, the '72 was just 35 amp. Likely the voltage output was barely 14 likely less. The newer alternators had vastly higher outputs and would be able to max out at well over 14. Think of voltage as pressure, higher pressure more flow. Perhaps it's producing a voltage spike and the fuse blows. 

[njp.18]

16 minutes ago, datzenmike said:

The stock alternators didn't make much power, the '72 was just 35 amp. Likely the voltage output was barely 14 likely less. The newer alternators had vastly higher outputs and would be able to max out at well over 14. Think of voltage as pressure, higher pressure more flow. Perhaps it's producing a voltage spike and the fuse blows. 

Mmm, should I try putting in a 15amp fuse instead of the 10amp

[thisismatt]

Fuses blow on over-current, not over-voltage. 

 

Does it blow randomly, or possibly when using your turn signals?

[datzenmike]

Yes indeed, and I agree but it's voltage that pushes the current. Notice your wipers are slower when idling with your lights on but speed up as the engine revs??? Current formula is voltage over resistance. So 12 v  through a 1 ohm resistance is 12/1 = 12 amps but if the alternator is charging at 14.3v then  14.3/1 = 14.3 amps.

[banzai510(hainz)]

clean the fuse contacts if dirty.

 

if you had the instrument cluster out clean the contaks also there.  I had a fuse pope and I reseated the cluster and was fine after that

 

DO NOT use a bigger fuse

 

My 521 had water filled up in the back light housing once. It never blew the fust but would make a BIG short. When it rained it filled up . so I drilled a hole on bottom of the housing for water to drain.

 

you check the voltage output across the batter while reved up?

Edited May 6, 2022 by banzai510(hainz)

[njp.18]

4 hours ago, thisismatt said:

Fuses blow on over-current, not over-voltage. 

 

Does it blow randomly, or possibly when using your turn signals?

it could definitely possibly be when using the turn signals, why?

[njp.18]

3 hours ago, banzai510(hainz) said:

clean the fuse contacts if dirty.

 

if you had the instrument cluster out clean the contaks also there.  I had a fuse pope and I reseated the cluster and was fine after that

 

DO NOT use a bigger fuse

 

My 521 had water filled up in the back light housing once. It never blew the fust but would make a BIG short. When it rained it filled up . so I drilled a hole on bottom of the housing for water to drain.

 

you check the voltage output across the batter while reved up?

about 14.3 volts when revved up to 3500rpm

[thisismatt]

Might have a short at signal lamp housing, or the switch. The switch carries all the signal current and they get dirty/burned from arcing.

[thisismatt]

3 hours ago, datzenmike said:

Yes indeed, and I agree but it's voltage that pushes the current. Notice your wipers are slower when idling with your lights on but speed up as the engine revs??? Current formula is voltage over resistance. So 12 v  through a 1 ohm resistance is 12/1 = 12 amps but if the alternator is charging at 14.3v then  14.3/1 = 14.3 amps.

 

Yeah, fair enough. 

[njp.18]

1 hour ago, thisismatt said:

Might have a short at signal lamp housing, or the switch. The switch carries all the signal current and they get dirty/burned from arcing.

ok, where is the turn signal lamp housing located? I sprayed some electrical cleaner on the turn signal switch behind the steering wheel and I didnt see any loose wires.