jonathanrussell

Hey @Trnelson...interesting read. Did this solve your oil consumption problem? Thanks...

To me, the best way to restore the battery area is to drill out the spot welds and remove the tray. If you do this, buy a nice, properly sized spot weld drill bit and extender, and practice removing spot welds without drilling through the body. You will then need to weld up the holes in the battery frame...or buy a new one. I use rivet nuts to re-attach the tray to the body. Not saying you should do this though. It is a pretty big rabbit hole because you will probably want to clean up those passenger side frame rails too...which is difficult without removing the fuel / brake lines and harness that passes through the firewall. Nice car.

I spent hours on this trying many ideas. What finally worked for me was.... 1) Loosen the nut until it is flush with end of the bolt. 2) Heat fork...several cycles. 3) Then, I used a long 3/8 socket extension. I rested the side of the male end of the socket extension on the nut head. Then, I hit the side of the extension with a bfh until it released. To be clear...I was not resting the end of the socket extension on the nut end and reaching a hammer inside the case. The socket extension is horizontal....parallel to the transmission shafts. The side of the male end of the socket extension rests on the nut. I hit the side of the shaft from just outside of the case with a bfh...being careful to not let the extension slip off of the nut head. This is hard to explain with words so I hope I am being somewhat clear. After several solid hits, the bolt moved.

So, sitting at a red light... Does the idle stumble with your foot on the brake? What about stopped at a red light using the hand brake instead? If it stumbles only when you have your foot on the brake pedal... check the brake booster. When sitting at a light with foot on brake, can you hear a hissing / air leak at your feet? Plug vacuum line to booster and test idle (careful if you drive). I have found that the booster can still work but leak at idle with brake depressed....which will make your idle drop.

I have been away for a few months but really enjoyed this discussion. Adding weight to the float is a really interesting idea that I will keep in mind. With added weight, you could trim the side of the float so you eliminate the problem with the float hitting the bowl on the front long ear carb. I have shaved a float before but didn't think of adding weight. FYI, I shaved it by sanding it. Solved the clearance problem but...reduced weight. I know we all end up solving our float adjustment problems in different ways but here is what I have settled on. I use two rear lids and two short needle jets. The long ear, long needle valve 72 idea for the front carb was....to me... a mistake. I don't pay any attention to measuring how many mm down from the top of the lid that the fuel level should be. I remove the piston domes, pistons, and drop the nozzles down 10 full turns. Then I set the float tabs so that the fuel sits at or just below the top of the jet. I tune with a colortune. O2 sensor would be better and I will try that some day. One last thing. Take a look at some of the photos of needle jets earlier in this thread. Notice that the stock original needle jets have a needle that is larger in diameter, is nicely rounded at the tip, and for me at least moves up and down more precisely. New needle jets are cut straight at the end, are thinner diameter, and rock around a lot. I think this, combined with the curved tab come together to make it really easy to have new needle jets get tripped or stuck on the curve of the tab. Just my theory. Anyway...great read. The fuel density theory and idea to add weight are really interesting angles to think about.

It has been a couple of years so make sure what I remember looks reasonable. I installed the energy PU bushings in the same transmission mount you show here. You are right...they are too long. I removed any sleeves from the rubber bushing and my recollection is that they slide right into the mustache bar hole. I solved the "too long" problem by using a belt sander to remove material on the bushing. I am pretty sure I removed material from the outside portion of the bushing. It was tedious because I wanted them to fit snug and didn't want to remove too much material. So, I worked a little at a time until I had removed the same amount of material on all 4 sides and the fit was snug. Hope this helps. Sorry I don't recall 100%.

Here is a short video of the tool being used. I know others have had them made too .... which is how I got the idea. I want to say Mike has one but I could be mixed up. MustacheBarTool.MOV

I don't know if this qualifies since I paid someone to produce it. It is a mustache bar bushing press tool. When used in a press, it folds the metal bushing sleeve tight at the original angle.

Hi. Welcome. So, I assume the original engine is in the car now. Why are you going to rebuild it? Do you have compression numbers? Does it run?

Another thing to think about. There are two ways the ignition / distributor timing plate can be adjusted. First is the obvious way we all use to loosen the set screw on the back side of the distributor and then rotate the distributor so that the timing plate hits the Retarded or Advanced line we want. That plate though fastens to the bottom of the distributor with a set screw that screws up into the bottom of the distributor and the hole in the plate where the screw passes through is slotted and adjustable. If you loosen that screw, you can "macro" adjust / rotate the distributor. What I usually do is use the normal timing adjustment set screw (on back of distributor) to adjust the timing plate so that the distributor points to the middle line (not retarded, not advanced). Then, I start the car and check the timing with a timing light. If the timing mark doesn't line of with the TDC mark on the damper pulley, then I try and adjust the "macro" timing adjustment by loosing the set screw under the distributor and rotating the distributor....trying to get the timing light to show 0 degrees advance or TDC. Once done, I tighten the set screw under the distributor. Then, I adjust / advance timing to spec using the normal timing set screw on back of distributor and timing light. If you can't get the timing in range then you may have a slightly more involved issue. As ZH mentioned, could be damper slip. Could also be the oil pump spindle gear is off- See FSM and Monroe book for details on setting engine to TDC (compression stroke) and checking the spindle direction (with distributor removed). Monroe does the best job describing a method for installing the spindle and turning the oil pump body 1/2 a bolt width clockwise while passing the spindle gear into the crank gear.

Antifreeze and ATF?

Just seeing this. This is a really good discussion. I just wanted to offer two things. First, if you have never driven, felt, both bushing types, don't discount the possibility that people are different, ride quality is subjective, and that you may or may not agree with the consensus. For a long time I had the idea that, based on consensus, Energy / PU bushings would be harsh and that I wouldn't like them. So, I avoided them until about 2 years ago when I was refreshing one of my 240zs. For this one, and for a lot of reasons, I decided to go the PU route. I installed PU everywhere except for ...... anti-roll bar (used rubber), t/c rod, (used rubber front and back), and strut bump stops (used Koni). Springs are old schoold MSA blue lowering springs (NLA) and red Koni classic strut inserts. And, I am using the original front-only anti-roll bar setup (key in my opinion to good ride quality). I used / over used the lube that comes with the Energy PU bushings. I was really shocked by the results. No squeaks. I personally don't hear any additional road noise (or drivetrain noise). I love the responsiveness. The ride is excellent, as is the handling. Again, all of this is my opinion based on my experiences. I should mention though that I have felt harsh in a zcar. When I was a kid I installed derlin camber bushings in my 280z with lowering springs and big anti-roll bars. That car was harsh. I am too old for that now. One KEY point too regarding my 240z is the tires are 195 70 14 Vredesteins. At some point I will try 16" wheels and 205 55 tires, and see what the impact is. I should also mention that my 75 year old dad loves the balance (ride / handling) of this car and he insisted on rubber bushings when I refresh his 280z. Second, some of you know that I had a swage shaped tool made to use in a press to install the stock mustache bar bushings. My offer stands to ship to anyone to borrow, use and return to me.

Just reading this. Great that you got the wedge bolt out. I had a hell of a time with this about a year or so ago. I ended up doing multiple heat cycles on the fork, followed by using a hammer to hit the side of a long socket extension that was resting on the threaded side of the bolt. I rested the socket side of the extension on the loosened nut and hit the part of the extension that was outside of the housing with a hammer. In other words, the extension was reaching into the housing from the front / big opening...parallel to the shift rod. Like you, my transmission didn't have the convenient hole in the housing like the zx transmissions do. I ended up replacing the seal and the o-ring. No shifter leaks now.

Kind of an old post but I am just now reading it so.... I actually used a bench grinder with a medium to fine stone. I press the bushing surface against the side of the spinning stone. And, I don't press the bushing against the stone with the grinder powered on, running full speed. I power it on and off intermittently while I press the bushing against the stone. I never let the bench grinder spin at full speed. Took some time but worked well and ended up removing material evenly. Could also use a belt sander mounted in a vice would think. If a belt sander, I would probably use something like 120 grit paper.

I have solved steering wheel shimmy issues with new wheels / tires before also. My silver 240z has a bit of shimmy between 60 and 65 mph. It has new suspension components everywhere. I know for a fact though that my wheels aren't totally straight (and require a lot of weight to balance) so when I replace the wheels I expect all of the shimmy to clear up. At one point in my life I did find that straight wheels could shimmy with cheap tires. In that case a change to better tires solved it. As you mentioned too, I have found that wheels that take a lot of weight to balance often have problems with shimmy on a Z.

If it were me, the first thing I would check is the cold start valve and thermotime switch. If you pull the cold start valve harness and connect positive and negative to the two cold start valve terminals, does the cold start valve spray? If yes, and you manually spray the cold start valve when the car is cold, does it start?

Both of his caps have the short ears and thus need the short, easily available, needle jets. FYI, the long ones are available from a company named Wells. I think I purchased from Rockauto. For those who have long ears though...I actually like madkaw's method....re-drill and use the shorter needle jets...OR locate a short ear bowl cap and replace. I just don't like how the long ear / long needle jet config works in the bowls. I checked Rockauto. I am not seeing the same options I was able to order a year or two ago. But, the kits I ordered at the time were similar to this offering on ebay (see below) where the kit is for one carburetor but it includes two needle/seat bodies...one short and one long. You assemble the one you need. https://www.ebay.com/itm/Carburetor-Repair-Kit-For-1972-Nissan-240Z-C158SV/173967875276?hash=item28814b1ccc&_trkparms=ispr%3D1&enc=AQAEAAADIKvsXIZtBqdkfsZsMtzFbFsbX3WcW5fmB%2Fx7ZbaZTyex8i7n1lQ38Wwv00fEvu8N9rCKQfFKON4NOQ3D8SmHNmA9jykbbq7wo13Cux%2BQpQ3L3ZF3gVbgO8vQKDrboxJ1C0IL4WhifbrVuv%2BruWod44VIrGRv0W8Y3jhtVPUlLpPcPJ8Mt3spoLlpiG7pEojg0tsI5QlxVSZAbdj6nX8aWti2H5zgmCzjZdfpI%2FvtdnTddUi8QHBH%2FCN847fCCi0C7dp1gldpOZFzndtTPHwHwqkQWLU9M3NnyRmNXuFiR9JDYvB0s%2FtUZnXwqTVUQAkILFugvcotpy455CcSX8qQUqBTtKIycchyAFPPOdX5WGwx3bt53OE9IOrX2QmbxujOoxs2HSSfUza7M%2BcNa5CgWfvyIatuLAv7fVy2Ss2jVIKAZ%2FglxKDQczdFSGy4Rlm1vSZVZ3%2Fvze%2FllamSoXKYwCF55BEqng977c6wt5x2%2B%2BFPkQ%2FGTH0nJhNO0u6gx%2B6vt%2BYZ4rwai6oaOYtPOTfdIh1IKeVFNobeM%2FpL8ub4SOpA9MfKsW%2BKzeHcT35APm5GBWp9%2BwaOKZ5suqp6807VdPtbMj8h24Fgf0QCJ7VdSnz5t1%2FCPU7QgoC9XackNd2Fn606d6qwqInQsH7xXkCXCPaMfgmU9XUVVixkCarpdO99N9SQSvR8YX6JUPyIXjuTV4QV6Oi5QK3BZ4zMv4mw031u6lRl7p6yogLknt8RCmdCmktQOPTG7XAM0%2FbLROPDSE1%2BJgJE%2FEi45FCQe2N5gbFm2Zxs1GAepj2rtNjaz87ucRlh7hrhrQn%2Bu14r53qb1IyfRCgWcukjEzfKyP4Bqvtl4YGinjBVrOKrTz%2Fc7%2BrmkcyZUp%2BU%2BnNMKuz1JsVao2fVBzI1lzqBElXPWM7y7F9F8mY47se362zX6W99XvqQn8NHnsa5eGOI3Or4ZcbJO4z2A4xGlk2NBL8XFAC%2FK%2B3q0RTu9v3icCbPNRMS6xASFQjK1va57IeVyjMybxyVAwHnEWYlkREG2vElt6C8CukkpTDLC%2BQSqPqJWnqplAnp&checksum=173967875276bd133e6b6a8147c0a38f7c54e304c2c3

So, the drawing below shows you how the tab should sit in relation to the metal float arm that attaches to the float cap ears. With the orientation shown in the photo it curves a bit above the parallel line of the top of the float. In the drawing, if a long needle jet were installed, either the tab would be drastically bent down OR the float arm would be bent and the travel possible for the float would be severely limited. Also, regarding your measurements. I can tell that your short needle jet is about 1" which is about the same measurement I am getting in MM...what I wrote above- 25.25mm. I agree with what Patcon said. ZT carbs come to you in great shape and I would say decently adjusted. The carbs I have received though (two sets) have benefited from more careful adjustment of the float levels. Don't get me wrong though...they do awesome work. Hope this makes sense and helps.

Here are some measurements for you. I opened up my 72 3 screw carb set from my 24k mile 240z I am refreshing. I don't think these carbs have ever been touched. They even have the original needle jets. Anyway, the front carb has the caps with the longer ears. The length of the front cap ears from cap to the end of the ear is approximately 18.1mm or .7125 inches. The length of the front cap ears from the cap to the approximate center of the pin hole is 14.15mm or 55.70 in. The rear carb has the cap with the shorter ears (same as what your 4 screw carbs should and do have both front and back). The length of the rear cap ears from cap to end of the ear is approximately 12.78mm or .5035 inches (consistent with what you measured). The length of the rear cap ears from the cap to the approximate center of the pin hole is 8.52mm or .3355 inches. So here is what I think and others can weigh in as to whether I am understanding correctly. You have 4 screw carbs that have the correct float bowl lids with the short ears (or towers) both front and back. The problem is, someone installed a needle jet kit at some point that is for a 72 carb setup so your rear carb has a long needle jet and a short ear lid....which will / should never work. I think that if you install two short needle jets and set the float levels you should be in business. Wells makes rebuild kits and they sell short or long needle jets. If my notes are correct, CK749 is the short needle jet kit. You could also just order needle jets from ZT because I think all they sell is short. If I remember and understand what you wrote above you are struggling to install a short needle jet on the rear carb. What the prior owner probably did is severely bend the adjustment tab to force accommodate the long needle jet. So, you may need to do some tab reshaping. Use your front carb cap tab as a guide. Hope this helps.

One thing Ztherapy does that is sort of impractical for most of us to do ourselves is they replace the bushing in the carb bodies that the throttle shaft passes through. On worn carbs, the old bushing becomes a vacuum leak...making it very difficult to get consistent adjustment. So, you might want to test yours for leaks. You could raise idle to say 2500 rpms and spray starter fluid where the shafts enter the carb bodies. If idle changes you might have a leak. Not sure if you can send the bodies to ZT and have them just do the bushing work but might be worth asking.

I will share what I know that might be relevant to your problem. 1) Your car year and the fact that you have 4 screw carbs should mean that you have the float bowl lids with the short ears that the pin slides through to hold the pivoting float assembly. You should have short needle jets in both carbs that are 25.25mm long (measuring from end of threads to end of body...(not including the actual needle that moves in and out of the body). In 72, Nissan changed this so that the front carb uses a longer needle jet (27mm apx) and longer ears on the float bowl lid; the rear carb is the same as the earlier 4 screw carbs. So, it doesn't really make sense that the shorter needle jet wouldn't work on your carbs. They should both be short...front and rear. Questions that come to mind are.... - is the needle jet in your rebuild kit shorter than 25.25mm? If so then maybe it is the wrong kit? - Could your carbs have been swapped with long ear float bowl lids? I personally don't like trying to make the long ear lids work with the short needle jets. I have never been able to add enough washers to work before running out of threads to securely hold the needle jet in place. 2) Personally, I have never been able to get the long ear lids to work reliably. On my 72, I swapped the front lid with a short ear lid from another set of carbs. My recollection is that the lids will interchange regardless of 4 screw or 3 screw. So, on my 72 I run short ear lids and short 25.25mm needle jets. The problem I have with the long ear configuration is that it places the float lower in the float bowl chamber. In my experience this causes the float to hang on the side of the float bowl as it rotates through its motion. The result is a needle jet stuck open and overflowing bowl. I also don't buy into the engine angle argument that resulted in the change to a longer ear in the front carb and thus the changed fuel level measurements described in Technical Bulletin TS73-10. I subscribe to, and many disagree, the method of setting floats where you equalize the fuel level directly at the nozzle tubes with the mixture nut turned 10 full turns down (bigger topic but if you are interested, search and you will find lots of discussion about this method). 3) Finally, I will offer that I have found it really important to make sure the shape of the metal tab that you bend in order to set the float level is relatively flat and not overly curved. The new aftermarket needle jets are thinner than the original ones. Because of this, they get hung on the tabs if the tabs are curved too much. Whatever you do, I think it is really important to spend the time getting the float levels set right. If they are not set right, you will find you can't get the carbs adjusted at or near the 2.5 turns down of the mixture screw. If you find you need 3.5+ turns or 1 turn or the mixture screw turning doesn't elicit any effect, it is a good sign that your floats are not set right.

How did you deal with the portion of the head gasket that extends over the timing cover? Did your's survive removing the timing cover? The only other time I have intended to remove the cover without pulling the engine apart, the head gasket ripped. I thought at the time that I would cut a new replacement gasket but ended up disassembling the engine for other reasons.

@240260280 What do you use the flange Sealant for? Rear main bearing cap seals...left/right? Thanks!

Thought I would resurrect this thread to add some info that I learned yesterday working on my own speedometer problem. My speedometer on my early 72 suddenly stopped working Friday. My first thought was speedometer cable. I removed and verified that it was just fine. Next thing I tested was the gauge. I was really hoping it wasn't the gauge because I see no practical way to pull the gauge without pulling the dash. Seems like some people have done this successfully but I don't think I could. The way I tested the gauge is I attached the cable to the gauge and disconnected from the transmission. I pulled the transmission side of the cable from under the car so I could hold the transmission end while watching the gauge. As Zed Head mentions above, if you pull the cable out a bit and turn while pushing, you can feel the cable seat into the gauge securely. Once seated I simply turned the transmission end of the cable counter clockwise (by hand, no drill needed) and was able to see the speedometer needle move. So, gauge was fine. Next, I removed the speedometer spindle / housing at the transmission. If yours has been in there a long time it can be a little challenging to remove. Tap on it a lot (without damaging threads). Remove the 10mm bolt and metal piece that slides into the spindle housing slot. I used a flat head screwdriver and the housing slot to kind of pry the spindle housing out. Be prepared for transmission fluid to pour out a bit. What I found is that the plastic speedometer gear was damaged badly: the teeth were worn away on one side. I installed a new spare I had on hand and my speedometer works as it should again. Remember to line up the slot square relative to the bolt hole. When you reinstall the spindle and housing, it will feel like there is a lot of resistance. Oil everything up, especially the o-ring (use a new one). Press firmly and it should pop in. Don't hammer (see below). While you are at it, think about whether it is time to replace transmission oil. At a minimum, top off your oil if any leaked out. Finally, connect the speedometer cable at the transmission. Follow what Zed Head wrote.Rotate the cable pulling and pushing until you feel it seat in the gauge. Then, hold it in position and slide the cable into the transmission spindle slot so that the cable will be driven turned as the car moves. Tighten up the bolt by hand. I am not totally sure why this happened. I refreshed the transmission last summer and I remember having a difficult time re-installing the spindle / housing. Could be that I got too aggressive forcing it back in. Hope this helps someone dealing with speedometer issues....and especially eliminate every other possible problem before heading down the path of removing the gauge or worse the dash.

Your 280z is a 76 isn't it? Your intake manifold is the 75/76 variety that doesn't have the webbing between ports. My 75 has a heat shield though that attaches to the underside of the intake manifold. I can't see a heat shield in your photos. If there isn't one, you might reinstall, or locate one and install. If that doesn't cool your rail, you could also wrap your headers or shield them with something like what I used for my 240z manifold. heat shield material