Miles

I ran a compression test, adjusted the valves and hooked up a vacume guage. Compression: Cylinder/PSI 1/150 2/150 3/149 4/145 5/145 6/ 125 (190 with shot of oil) All cylinders held pressure. Vacume guage connected to the master vac connection on the balance tube shows a vibrating guage reading. The needle vibrates vigorously between 15 in. hg and 16.5 in. hg. I have noted that there is one tapet clacking and had a shop adjust the valves about 3 months ago. The valve continued to clack and there was a noticable drop in power. Yesterday I checked the valve clearances hot and cold using the appropriate valve clearances. They all were adjusted so tight that a feeler guage would not fit between the valve stem and the tappet. I readjusted the valves cold at 0.008 in. (intake) and 0.010 exhaust so that the gauge made a stiff sliding fit between the valve stem and the tappet. The clacking valve is still present and the engine still runs rough through all speeds. The misfire is most noticable at idle especially when cold. All of the ignition parts are new except for the coil. I am going to swap in a spare coil today to see if that helps. Since the compression on cylinder 6 was lower then the rest of the cylinders, could the head gasket have sprung a leak near cylinder 6? I have checked the usual places for vacum leaks using carb spray and water. The carb gaskets seemed to leak so I replaced them. The carbs are new rebuilt from Ztherapy. Anything in a new rebuilt carb that would cause the engine to misfire? What could cause the clacking valve if the valve clearances are ok? Thanks Miles

I pulled each plug wire off at the distributor cap and there was no rpm drop on number 3 cylinder. Then I pulled the plug wires off at the the plugs and there was no rpm drop at the number 3 cylinder. On all of the cylinders other then number 3 there was a rpm drop when a plug wire was removed. Could this be a burnt or out of adjustment valve? Thanks Miles

I installed rebuilt SUs from Z Therapy about 2 months ago to fix a rough, misfiring L24. It ran well for about 2 1/2 months and then started running rough like a bad plug or ignition problem. It also seemed to be losing power. I checked the ignition for misfiring clues even though all of the parts are new. The ignition seems to be working as it should. Then I checked for intake leaks. The carb gaskets leaked when I shot them with carb cleaner so I replaced them. The car still misses and idles rough especially when it's cold. The misfire improves as the car warms up. The engine does not have the power it used to have. Up until now it pulled hard and I could spin the tires in 1st and 2ed gear. The car sounds like: rrrrrrrrrrrrr blump rrrr blump blump rrrrrrrrrrr blump blump blump rrrrrr blump ................... I did have the valves adjusted just before I installed the rebuilt carbs. Could this be a burnt valve? What would the symptoms be if a valve is bad? Thanks Miles

I just bought some new shoes for my 240Z from KVR and the drums won't fit over them. The adjusters are turned all the way in. I ended up reinstalling the old shoes so I could use the car. The old shoes fit good. Do the new shoes need to be arced. Thanks Miles

Drax I advanced the distributor as far as the set screw would allow and under a timing light the timing mark is right at TDC. With the no. 1 cylinder at TDC center the rotor is pointing a few degrees past the no. 1 connector on the distributor cap. I tried moving the rotor by loosening the distributer, lifting it, and repositioning the rotor to line up with the number one connector in the cap. When I drop the distributor back in it either wont go in due to the rotor position or it will only drop into place if the rotor is back to its' original position. It seems that when the distributor is lifted and the rotor turned it will only go back in one way. I am assuming that the drive is slotted in a way that only allows it to be installed one way. Using a timing light I can turn the distributor clockwise and retard the spark alot, but can't get much advance going the other way. Thanks Miles

Just doesn't sound like it would work. The reason this came up is that my engine lacks throttle response since I installed new Ztherapy SUs. After tuning the carbs I dailed in max advance, but the timing light shows that I am dead on TDC at idle. Throttle response is a little better, but not like with my old carbs. Thanks Miles

A friend just told me that I could maximize the advanced timing of my L24 by flipping the rotor 180 degrees. Is that true? Seems like it would result in severe misfiring. Miles

I just bought a set of 240Z brake shoes from KVR. The person I talked to at KVR said I would need to chamfer the leading and trailing edges of the shoes before I Installed them. I have never heard of this before. If true, how much of the edge needs to be chamfered? Thanks Miles

Jeff If you don't watch the driveliveline phasing you may end up bolting the trans mount too high or too low which will result in driveline vibration. Don't just measure 5 1/2 in. from the output shaft to the tunnel. Remember driveline phasing is an issue when doing the hybrid setup. I first measured the angle of the differential input shaft using an angle finder and then figured the angle of the trans output shaft needed to get everything in phase. Then I bolted the transmission mount to the transmission tailstock and then held an angle finder on the end of the output shaft while my son slowly jacked the transmission and mount up towards the tunnel. When the output shaft was about 5 1/2 in. from the tunnel I watched the angle finder until I had the angle I needed to get the trans and rearend properly aligned. With some fine up/down adjustments I was able to dial-in the correct angle before I bolted the mount to the driveline tunnel. Once in place lock up your jack so it won't move and go to the hole finding and drilling step inside of the car. Hole drilling step: The other tricky part is drilling the holes for the mount. There is no room under the car so you will have to drill from topside. Just use a very small drill to find the holes in the mount by eyeballing the location of each mount hole and then try to hit the hole with the small drill bit from inside of the car. You may have to drill 2 or 3 small holes until you hit the center of the mount hole. I usually got it on thre 2ed try. Once located drill your bolt hole and install a bolt and nut to hold things in place. Repeat until done. It is easier to do then to explain. My driveline phaing is perfect with no vibrations. MIles

I used the MSA kit to install my 350 sbc and T5 trans/bellhouing. The shifter comes right up in the hole and using a B&M shifter corrects the bellhousing 15 deg. offset. You can see photos of the mounts at my web site below. Miles

Found the problem. After painting my car last week the body shop techs reversed the wires on two of my marker lights sending power directly to ground. The painter sprayed the marker light wires so the techs couldn't match the color codes correctly. Switched the wires and all is well. Miles

Found out tonight that my tail lights, marker lights and parking lights are all out. These are all on a common circuit and fuse. Checked the fuse and it was blown. Replaced the fuse and disconnected the tail lights and marker lights and the fuse blew when I turned on the lights. I recently had the car painted and the body shop only removed the marker lights. Unplugging the marker lights still results in a blown fuse. Any ideas where to look? Thanks Miles

All of my instrument lights went out. I looked at two schematics and they don't show the instrument lights. Are they fused? Is there a common plug for the instrument lights? Thanks Miles

The steering on my 72 240z has gotten very stiff. Tires are inflated properly. What is the usual cause of stiff steering on a Z? Also, My brakes pull to the left. It feels like it is the left front brake that is causing the problem. All brake parts were replaced and only have about 1000 miles on them. Any ideas? Thanks Miles

Chase The shifter does vibrate less whent the clutch is in. Any way to check the vibration damper or just replace it? Thanks Miles

I am getting lots of white smoke on start up and the engine runs rough so I am going to pull the heads off of my 350 sbc for a rebuild. I have never done this before and have some questions: Distributer removal: Should I set the engine at TDC on cylinder 1 and mark the position of the rotor and distributer body? Lifter replacement. What do I need to remove the lifters and install new ones? Push rods. Should I replace the push rods? Manifold sealing. What is the best method of sealing the intake manifold? Head gasket. What is the best head gasket to use? Thanks Miles

I am having my 240Z painted next week and plan on replacing the front window weather seal and the rubber seal that goes around each door. Has anyone here used the MSA door seal? If so, were there any fitment problems such as the door not closing after installation? Thanks Miles

Jon You are correct. Ztherapy uses the ball type of valve. I just installed a new set of Ztherapy SUs on my 72 240z and it runs like a new car. Miles

Thanks for the checklist. I'll get under the car this weekend and go through the list. Miles

Buy the rebuild kit from Ztherapy as it has an improved needle valve assembly to prevent overfilling the float chamber which may flood the carb. The stock and cheap rebuild valves can cause flooding and a fire. I also recommend buying the Ztherapy SU video. Miles

I had this same problem on my 240z. It was due to a loose/corroded wire going from the bias resistor to the coil. I knew it was this particular to look for because each time the engine quit the tach would go to zero instantly indicating it had been cut out of the circuit. I replaced the connector and no more cutting out. Check your ignituion wiring. Miles

While at freeway speed today I noticed that my stock 240Z was vibrating. I could feel the vibration through my seat and through the shifter. The vibration seems to go away when coasting with the clutch in. I feel the vibration just sitting with the car running at different RPMs. The engine runs really good and I recently just installed a set of rebuilt SU carbs from Ztherapy. Any ideas or things I should check for? Thanks Miles

What year rotors and calipers are used and will I have to swap out the 240z MC for a zx MC? I haven't seen this swap on the forum before. It appears to be easier then the Toyota swap. Thanks Miles

I just came across a break upgrade for 240z using 300zx rotors and 280 zx calipers for at zandzxparts.com. Has any one here tried this combination on a 240z? The web site claims a 50% improvement in brake performance based on a $600 kit. Seems pricy for what you get. Miles

I mounted a Wilwood pv in the tool box behind the passenger seat and plumbed it to the the lines that went to the stock pv also just behind the passenger tool box. I used braided SS brake lines and some metric to standard adapters I got from a local off-road vehicle shop. I can adjust the pv easily from the driver's seat and the pv is protected from getting knocked out of adjustment. Prior to installing the pv the rears would lock up. Then I added some KVR pads up front and the V8 Z now stops without rear lock up or fading. Someone here has pic on this pv set up. Miles