M_Motorsports

Able to get the car started but is chugging and not smooth. Had to advance the dizzy all the way. Could the chain be stretched or a tooth skipped?

The car gives a few false starts/turn overs while cranking then resorts to the starter just turning over the engine. I'll try the starter fluid and see if it will stay running. I'll also recheck the seating of the dizzy and adjust the advance.

Yes, I could feel the release of air thru the spark plug hole as well as using a soft straight pipe cleaner to show the cylinder moving up.

Background is a 72 race car I have been working on since last Fall. Ran fine then. Over the winter had replaced the oil pump and when it come out the long shaft did also. Put the new pump on and did not align the long shaft correctly. Went on to have the SU's rebuilt and reinstalled. At that point I pulled the valve cover off, aligned #1 cylinder to TDC, pulled the oil pump off and reinstalled it correctly. The top of the shaft is in the correct position according to the picture in the Haynes manual. Dizzy rotor points to the #1 cylinder plug wire. Installed everything back together and made no adjustment to the dizzy. Dizzy has a Petroniz Ignitor and I have both gas and spark. Turns over and seems to want to start but won't. Am I overlooking anything?

Spent the day reverse bleeding the MC and 4 corners with success. I think the greatest improvement came working with the front Arizona Z Wilwood calipers. I removed the calipers from the frame and turned the calipers on their side.. These Wilwood calipers have 4 bleeders per caliper (?) and the ss brake line enters thru the side when mounted. To get all the air out you really need to turn them on their side and rotate them so the entrance of the ss line is on top. I used a reverse bleeding gun so forced any air back thru the top, thru the system and out the reservoirs. I guess if you use a more traditional method of forcing the fluid out thru the calipers you would need to position the bleeders at the top. Now have a much more solid feel to the peddle.

Can a reverse bleeding tool work where you force brake fluid from the calipers back to the MC? Can this eliminate the air bubbles that are somehow trapped in the calipers back thru the system? Have one available from a friend who uses one when he bleeds his brakes alone.

Interesting thread. I'll spend the weekend re-bleeding via these instructions. Let you know.

What I did was mount the MC to the booster and ran a hose from the side bleeders and looped it up into the reservoirs and pumped the peddle till fluid returned to the bowl. Sound correct?

Miles, Thanks for the details. It's pretty complete about the operation of the switch. I will assume the switch is a no fail operation therefore will rule out doing any by pass of the switch and look else where for a solution to the soft brakes. I will look at additional bleeding of the brakes first before anything else.

Yes it does and from what AZ told me is to remove the residual valve from the front reservoir. This is the reservoir that services the rear brakes. This was done.

Having problems with a brake upgrade with my '72 race car. Have newly installed Arizona Z front brakes, 15/16 MC from AZ but still running with the oem drums. Have pulled out the proportioning valve from the rear area of the car due to prior owner installing an after market PV in the interior cabin. Adjusted the pushrod from a new reman. booster to what I believe a correct length. On the initial pump the pedal goes to about 2 inches from the firewall and soft. Pedal needs to be pumped two times to raise up the pedal position and make firm. Have bled the brakes at least two times. Same results. Stumped. Can the distribution valve located under the MC be malfunctioning? Should I just remove it and plump the brake lines with a straight and a T unions? Would like a solid pedal with just one push.

Thanks

So it would not be as simple as to insert the driveshaft and bolt it up?

While working on my steering rack and oil pan replacement I removed the oil pump cover and the oil pump driveshaft dropped out. What is needed to correctly replace the driveshaft in its correct position?

Thanks for the suggestions Chickenman and Northwoodsz. In further research I may be causing more exhaust to enter the cabin by having the 2-3 inch holes placed in the rear window due to the neg. pressure. Upon checking, there is so many openings under the rear (fuel cell) and back of the car I don't know how I would seal everything. I will have my exhaust person try and maneuver the exhaust farther back and/or out the right side.

Reconditioning a '72 240 race car and have had it out for a few HPDE events to work out issues. One is the exhaust fumes that enter the car while on track. Symptoms are watery/burning eyes and taste of exhaust. I know of all the problems 240's have with negative cabin air pressure and exhaust kicking back thru the exterior of the car. Being a race car it tends to have a lot of gaps and missing gaskets/seals/trim. My exhaust end under the car and not carried all the way back to the rear bumper. I have noticed a few other race 240's with Lexon rear windows that several 2-3 inch round holes are cut across the top or bottom of the windows. I assume they were having the same problem and added the holes so exhaust could exit the interior while the side windows are down. Have any racers found this to solve the problem or are they only adding more spots for the fumes to enter? Should the holes be across the top or bottom of the window? If you have done the cuts were they done by a glass company or a diy? Any other way to exit this exhaust? Would extending the exhaust pipe farther back be of much help? Thanks.

To az240: I don't believe your 8 1/2: booster would fit in my 240. Thanks, but you should go ahead and contact RB26. Contacted all the major auto supply stores and all say they are out of stock and don't know when they would have any more. Contacted Carbone Co., who remanufactures boosters, to see if I could send mine in to be done and they said they can not do a 240z. Motorsports says they are out of stock till who knows when. So, still looking.

Need a brake booster for a 1972 240z.

That will be my next step. Just wanted to know if elec. could be the problem.

Bought a '72 Z and the speedometer is not working. Having disconnected the cable from the back of the speedometer, jacked up the car and found the end of the cable turns with the car in gear. There has been some rewiring due to the car becoming a ace car and there is no longer any wiring connected to the back of the gauge. Besides the original wiring to light up the gauge is there any other elec. needed to run the gauge or should it be all mechanical at this point?