Weasel73240Z

When I eliminated the warming lines when I installed my ZTherapy carbs I ran my coolant lines exactly the same as you, works fine. I plugged the 3rd line in the T-stat housing, works fine. I attached a pic of my balance tube, I eliminated just about everything. The screw on top of the balance tube is not idle adjustment, its for running up the rpm's to balance the carbs. Only used when the carbs are being tuned. I'm not sure if your linkage will work. I bought a set of donor carbs on eBay when I bought my ZTherapy carbs to use as a core. I used the linkages from the core set. Hope this helps.

"Fixing" a blown head gasket with radiator sealing "gunk", is really the same as saying "I'm trying to ruin this motor". Replacing a head gasket isn't that hard, but you need some skills. The fix for a bad head gasket, is a new head gasket, there really is no other option. Sorry.

Did it run before the header? Won't crank, but it will run w/starter fluid? You're not getting any responses because you didn't provide any info. The guys on this board aren't going to drag it all out of you.

If your getting good spark, as well as proper fuel, air and compression, the only other major thing that would keep the car from running would be ignition timing. If the spark isn't firing when it should, the car won't run. But you need to provide more info to get really good answers.

Congrats, always love a happy ending!

Before you rebuild the dizzy, make sure you've done the cheap and easy stuff. You said you put in new plugs and wires, but did you also install a new rotor and cap? Those could cause a sporadic spark.

Here's a pic of my balance tube. The cloth braided hose from the PCV valve goes to the tube under the dizzy.

Front is 1, back is 6. Might be time to grab a Chilton's or Haynes manual while your at it. These cars are pretty simple to work on, but if you need that answered, you probably should read up a bit and learn the basics of the L-series motor. It'll make the process much easier. No disrespect, just honesty. Good luck.

Welcome Alex. The car looks like it has a lot of potential, but first thing is to undo anything the PO did, by the looks of his work.

How the hell is that a plus????? I told my wife she'd never be comfortable with the vacuum-assisted brakes and lack of power steering, so she shouldn't drive my Z. Sure, its BS, but why would I want my wife driving my car? I don't ask to use her blow dryer, do I?

That rubber plug was covering the PCV valve. Thats no good, and it may be part of your problem. That should be routed to the tube below the distributor that comes out of the side of the block.

I wanted to follow up on this post. In reviewing my manuals, it looks like the initial timing for my L24 (with D609-56 dizzy) from the factory was 7 degrees BTDC. Looks like the mech. advance gave a total of about 9 degrees of additional advance, and 7.5 degrees more from the vacuum advance. So starting at 7, the total advance should only get to about 23.5 degrees. I think for the most part, ignition timing relates most directly to the camshaft, and that's stock in my car. When I installed the ZX dizzy, I advanced the timing to about 12 BTDC, based on what I read here. The ZX dizzy has 17 degrees of mechanical advance, and I'm using the vacuum advance (with new breaker plate so it works) and full advance gets me to about 35 degrees BTDC at around 2,300 rpms. Most of the stuff I read says around 35 total is about right. But, could it be that my hesitation around 4,000 may be from advancing the timing more than the cam can handle? :stupid: I'd go tweak the timing and take it for a ride, but its raining in MA for about the 28th day in a row so the cars in dry dock. I don't know how you Pacific-NW'erners take it. :classic:

I rarely push the car over 5,000...and I bet that's true of most guys on here. Not saying that the L-series can't handle 6,500+, we all know that it can, its just not practical for a street driven car to be winding it up to 6,500 very often. Between the color of my car, the sound of my exhaust, and the number of cops in Taunton, I'd be paying speeding/sound ordinance tickets every other week if I was regularly running it up to 6,500 rpm shift points. Either way, there's clearly something going on around 3,800 - 4,000 usually in the higher gears. I'm going to richen the mixture another 1/2 turn out, and see what I get. I'll keep you posted. Still wondering what I should running for intial timing and total advance with my set-up. It's a 1973 L24 (stock cam) ZTherapy SU's, ZX dizzy (E12-80) NGK plugs at .045 gap. MSD Blaster 2 coil. Any help would be appreciated. I have tried searching alot, but there's nothing as specific as what I'm looking for. I'd love to hear what guys that are running the same set-up as mine as using for initial timing, and whether they are using vacuum advance, or just mechanical. Thanks in advance for any help.

I finished putting the car back together last night. The valve lash adjustment made an improvement, but theres still something thats not 100% dialed in. I replaced the #4 plug while I was doing the valve work. I visually inspected the dizzy cap, put the timing light on the #4 to make sure it was firing (it was), and confirmed good plug connections. I still think the occasional "dead spot" in the powerband is a timing/advance issue. I don't remember there being a dead spot before I installed the ZX dizzy and got rid of the points. Right now I'm at 12 BTDC (initial) which gets me to about 35 degrees total (mech. and vac.) advance. The car idles great, and it pulls great right up to about 4,500 + most of the time. I rarely push it past 4,500 but the car would be glad to, in 1st or 2nd gear. But sometimes (typically in 3rd and 4th gear it seems) there is a dead spot from around 3,800 - 4,200. On the highway, when taching at say 3,200, if I try to accelerate without downshifting, I feel the "dead spot". I know I'm not getting max. output, and I'm actually thinking about paying someone look at it. Problem is, finding someone withing 50 miles of me that works on Z's. If any of the New England guys have anyone in mind in southeast MA that knows how to dial these L-series motors in, shoot me a PM. I'd know A & C Imports in NH has a very good reputation, but 100 miles on the highway is a challenge with my tranny/diff. set-up (4-speed w/4.11's).

I took the Z to my 1st gathering this weekend in North Attleboro, MA. Thought I'd share the pics. The star of the show was the lime green VZ car, it was stunning. Pretty good turnout, about 20, which is 20 more Z's than I've seen in the last 2 years. There were about 7 or 8 240's.

Definitely "wet" fouled, it looks like gas fouled.

I took my first stab at adjusting valve lash this weekend. I found that most of the valve's were about .002 too tight. Most of the exhaust were at .008 and most of the intake were at .006. I now have them adjusted to factory spec (.008 intake and .010 exhaust - cold). I still feel that something is "holding the car back" over 4,000 rpm's, and I'm curious what effect insufficient valve lash can have on performance? I did notice one other curious thing when I was taking out the plugs. The #4 plug was fouled, and all of the others were nice light brown, and clean. The valve lash at the #4 was just like the others, a little bit too tight. I've noticed this plug being fouled in the past, when the others look good. If the valves are adjusted correctly, what would cause 1 specific plug to foul over-and-over, while the others all look good? Thanks for any ideas/help.

The A/F mixture is adjusted at the bottom of the carbs. See #7 on the attached diagram. SU.pdf

When the advance plates go bad, the little steel ball bearings tend to fall down into the guts of the dizzy. That may explain why the advance works sometimes and not others. You may have a ball bearing jumping around in there screwing things up.

I should've known that..since I believe I got mine from you. :stupid: The Just SU's video is excellent and well worth the $20.

I bought a new breaker plate for my E12-80 at a Nissan dealer...still available but they ain't cheap (about $85 I think).

9 Available, if you have SU's...you need one. http://cgi.ebay.com/ebaymotors/CORVAIR-and-others-UNI-SYNC-CARB-BALANCE-TOOL-CORSA_W0QQitemZ220262592635QQcmdZViewItemQQptZMotors_Automotive_Tools?hash=item3348ac707b&_trksid=p4506.m20.l1116

Sticking advance sounds like a good guess. Are you running a stock 280Z dizzy, or a newer E12-80 type? The advance plate on the E12-80's are notorious for breaking.

Sounds tempting, but I told the wife I'd finish the boat before I bought another Z.

Oh yeah...it's terminal. I'll fly down to Knoxville, and I'll take that headache off your hands for a $1,000. Not terminal at all, very fixable based on whats visible in the pics.