Miles

I'll try rotating the rear calipers vertical. I need to figure out why the front brakes will sometimes lock either left or right wheel when making a hard stops during road testing. Could be air in the lines? Thanks

72 240Z with MM vented front and rear brake kits with 280ZX MC. Booster is a new 1975 280Z. Daily driver. Toyota front caliper setup installed five years ago using new remanufactured calipers . Rear setup installed two years ago, but calipers recently started leaking so I replaced them. Reaction disk is in place and MC push rod adjusted correctly. I did multiple bleeds with methodical slow bench bleed of the MC. Tried two new MCs: 280ZX and new Wilwood 1 in. The brakes were bled with a Motive Power bleeder. Normally this works well, but I could not get a solid pedal. I suspected that the 280Zx MC (seven years old) might be leaking so I replaced it. After replacing the original 280Zx MC with a rebuilt unit from Cardone (also tried a new Wilwood 1 in. MC) the brakes remain soft/mushy with pedal that will not pump up.There is long long travel to hard point to about even with gas pedal where pedal becomes hard, but slightly soft. Condition is worse with engine running. After checking all lines for leaks I inspected the front calipes due to pulling right/left while road testing. Inspection of the front calipers does not show any obvious leaks/wetness around the piston dust seals, but I did find a slick black residue on the caliper body below the bottom pistons on each side (see pictures). Is this enough evidence to replace the calipers (five years old)?

I rotated the calipers also so the nipple was vertical. I discovered last night that rear section of the MC is sucking air. I can bleed the air out of the rear section. After closing the bleed nipple and a few pumps of the brake pedal the pedal goes soft and I find air in the rear section of the MC. Today I'll run some tests on the MC to see if it is leaking internally or if there is a bad fitting in the pipe that connects to the differential pressure switch below the MC.

Air is some how entering the rear brake section of the master cylinder. After a short drive or just pumping the brakes I get a lot of air out of the rear brake section bleeder on the MC. The lines between the MC and the brake differential pressure switch are tight and dry.

Re-bled MC and calipers. Pedal came up firm after bleeding, but after four or five stops I was mashing the gas pedal with every stop and the pedal was mushy. The left front wheel locked twice so there must be a problem with the right front caliper. I am suspecting that the new Wilwood MC may be bad out of the box.

Car: 72 240Z Brake Configuration: Front: MM Toyota caliper 300ZX vented rotors. Set up is two years old Rear: MM 240SX caliper 300ZX solid rotors. New calipers to replace two year old leaking units New rebuilt 280Z booster. Reaction disk verified in-place. Push rod adjusted to just contact the MC piston socket so there is a just noticible contact when the MC is pushed into the booster. New Wilwood 1 inch master cylinder. Bench bled before installing. Wilwood proportioning valve plumbed into the rear brakes where the "residual pressure valve" (aka proportioning valve) used to be in back. New porterfeild R4S pads front and back Bleeding: Used a power bleeder to bleed all four calipers. Re-bled MC bleeder screws after it was on the car before bleeding the system. Bled the system twice and saw no bubbles after initial bleeding the first time. Differential pressure switch has not been activated. Research: Researching the archives indicates that long pedal travel and spongy brakes are a common complaint with the above setup. Problem: With the engine off, the pedal is spongy about first third of travel and then gets solid about even with the gas pedal. I noticed that this morning after the car sat over night that the pedal was initially hard as rock and high with no play until I pumped the brakes a few times and then they became spongy again and the travel become long again. Brakes do not pump up. They are just spongy the first third of travel an then hard with a little spongyness. Makes me think that there is a leak in the system. I am going through the whole system today looking for leaks at fittings and caliper pistons and rechecking theMC push rod adjustment. Why would the pedal firm up over night and then go spongy again after a few pumps?

Type this into the search function: four speed Muncie It has been discussed many times.

Don't buy from Autoparts world. Many problems.

Check out ZBARN for the hood, body parts etc.: http://www.zbarn.com/other%20Web%20stuff/Catalog%20Pages/ZX%20Used%20Body.htm

Shouldn't you have asked that question before you bought the new wheels? Try a tire store they can answer any question about tire and wheel combinations.

You might try ClassicZ as they deal more with stock Z cars. http://www.classiczcars.com/forums/forumdisplay.php?2-240z-260z-280z-Forums

Welcome If you haven't already done so, pick up a copy of the Datsun V8 swap manual from Jags that Run (JTR). JTR is the basis for most of the projects discussed in the HybridZ forum. JTR and the HybridZ forum FAQs will answer many questions as your project evolves. http://www.jagsthatrun.com/Pages/Datsun_Z_V-8.html Let the fun begin

In school I owned a 66 MGB roadster and a 73 MGB GT. Shifting was very linear and smooth with just a flick of the wrist. Do a search here at HybridZ for transmissions that are known to swap into the Z and then go drive a cars with those transmissions.

Silkier? What are you looking for? Close ratio? Short throw? What car is the trans going in? Be specific. I have used 89 Camaro WC T5 transmissions on two 1972 240Z SBC V8 projects. Both engines had mild street cams. Maybe 300 HP on a good day. I use shortened stock Camaro shifters, Camaro slave and Tilton 7/8 MC. Shifts smooth like a factory car. It is a daily driver. The T5 fits with room to spare. The only mods required were recessing the tunnel slightly for throwout arm clearence (see JTR) and enlarging the shifter hole on the driver's side to clear the shifter base.

SBC 350 starters tend to get heat soaked and then not work until they cool down. When heat soaked they just click or turn over slowly. So, does your starter work ok when cold and only click when hot? I solved this problem by replacing the stock starter with a gear reduction starter. My SBC engine always starts no matter how hot the engine bay is. Do a search for gear reduction starters such as Hitachi PSL 100 etc.

My 79 280ZX MC finally started leaking. After a week of searching, I was able to buy a new 79 280ZX MC from Autoparts world: http://www.autopartsworld.com/results/?PN=5554&VN=4294967250+4294967085+4294965736&N=0&Nr=AND(universal:0)<A class=bbc_url title="External link" href="http://www.autopartsworld.com/results/?PN=5554&VN=4294967250+4294967085+4294965736&N=0&Nr=AND(universal:0" rel="nofollow external"> My old Nissan factory 280ZX MC will be used as a spare, so I am having it rebuilt through Rock Auto Cardone Remove and Rebuild program. About $40. Now I need to find a source for the booster.......

Post some pictures

Best advice at this time is to take the car to an alignment shop and have a mechanic check out steering, suspension and brakes. The mechanic can check your wheel bearings while he is checking everything else. These are old cars so you have to assume that everything under the car is close to 40 years old and will need repair/replacement. In the interest of performance and safety you should plan on renewing steering, suspension and brake system components before you do anything else. Note that worn steering rack bushings will allow the steering rack to move and cause the car to wander and/or exhibit uncertain steering. Best to replace them with polyurethane bushings when you are ready as the stock rubber bushings allow more movement of the steering rack. Worn compression rod bushings can also contribute to steering problems and darting on hard braking. Have the car diagnosed and make a list of all the things that need to be replaced and then work the list. Also, read the spots off a 240Z factory service manual or Haines manual. That will be more efficient than trying to diagnose each problem as it comes up here. Be prepared to spend a lot of time and money getting your Z road worthy.

I had a similar problem on my 240Z. It may not be a short. I traced the problem to a broken solder joint inside the light switch. Soldered the offending joint and had lights. I also keep spare light and turn signal switches on hand so I can just swap them in when diagnosing light problems. It only takes a few minutes to swap out the switches saving time having to go point to point with a volt meter. Did you check the fuses?

What do you mean the rears are not bleeding correctly? By stainless brake lines I assume you mean the flex lines. Correct? I had the same questions before installing the MM Toyota front and 240SX rear brake kits. When my stock MC failed I went ahead and installed the 79-81 280ZX MC in anticipation of installing the MM kits at some future date. With stock brakes you have to push a little harder using the 280ZX MC. I drove around for about a year before I installed the MM vented Toyota front brakes. No problems. Three years later I added the MM 240SX rear disk kit. Concerning the stainless braided lines for the rear: The stock rear drum brakes and the MM 240SX rear calipers use different types of brake line fittings. Stock uses a screw in fitting and the 240SX uses a banjo fitting. So if you install stainless lines now you will have to replace them with longer lines that have banjo fittings later. Depends how long you anticipate driving with stock brakes. Note that the MM kits come with the correct stainless brake lines. As to the 240Z MC vs 280ZX MC question: can you use the stock 240Z MC with the Toyota front and 240SX rear swaps? I have heard the same debate of 240Z vs 280ZX MC, but I assumed that the Toyota/240SX swaps would require more fluid volume and went with the 280ZX MC. If the 240Z MC would work I'd like to know because I have a new OEM 240Z MC and my 280ZX MC is starting to show some wear. If someone is using a 240Z MC chime in. Note: If you go with the 280ZX MC, the push rod between the booster and the MC has to be adjusted longer than as for the stock 240Z MC. See the brake section and the FAQ section for discussions about how to adjust the rod. If not adjusted your brakes will never work properly and you will have a long pedal. If the rod is adjusted too long the MC will not empty properly and lock up the brakes requiring manual release of pressure by opening the MC bleed screws. You didn't ask, but I also installed a proportioning valve in the tool box behind the passenger seat. Some say it is not required for the MM front/rear set up, but I wanted to be able to adjust rear bias if I saw that there were problems down the road.

I bought two new remanufactured 240SX calipers from Napa and installed l them today. Pumped the brakes a few times and the new left caliper is leaking fluid around the piston. The fluid runs out under pressure. Anyone else have problems with Napa 240SX rear calipers?

If no luck here, try the Z Barn: http://www.zbarn.com/zbarn3.htm

There is no way to tell if the drums are still in spec without measuring them.They could have been turned in the past. You could take your drums to a machine shop and have them measured to see if they are still in spec. Or you could buy new drums then you will know for sure they are ok. I bought a couple of sets from Autozone.

I have a full set with tires (old). $275.00 Located in Carmichael California. Will not ship. PM me for details.

If the car is drivable take it to an Autozone, Kragen etc and have them check the alternator and battery. One or both may be bad. They should be able to test both if they are out of the car as well.