What next?!

[FastWoman]

Question for both of you:

I'm trying to take this mess apart now. My next step (and impasse) is to disconnect the EGR pipe between the two manifolds. (This is a '78 model, BTW, if that makes any difference.) I can't get any ordinary wrench in there anywhere. I'm thinking the best approach would be a crowfoot wrench on the big nut just below the back of the intake. The nut is 30mm, and my largest crowfoot wrench is 22mm. I'll need to go tool shopping to get a 30mm crowfoot, and the sets aren't cheap. (I might get an SAE set with a 1 3/16" wrench, which is 30.16 mm.) It's also a long trip into town.

So is that nut (the largest one) the easiest to get loose? I'm thinking it should be, but before I buy tools to use on it, it would be great to know I'm on the right track.

Or is there any other approach that's better than a 30mm crowfoot wrench?

Thanks, guys!

Edited September 23, 2010 by FastWoman

[Zed Head]

I had spent months driving my stock 1976 car around trying to figure out why it seemed to run rich. Gassy exhaust, sooty plugs, 16 - 18 mpg all the time. The fuel pressure checked right at 36 psi on a cold engine. Finally, over about a week, the gassy smell got terrible (one guy behind me actually flipped me the bird as he passed, it was that bad) and the mileage dropped to 15 mpg. I checked the fuel pressure hot and found that my FPR had finally gone completely bad, pressure was up around 42 psi, maybe higher while I was driving. I installed an Aeromotive adjustable regulator (high quality Craigslist bargain) for the same reason you are thinking and the car runs much better, running like a normal car now. Clean exhaust smell, the idle doesn't drop to 500 momentarily when I stop, mileage improved to 20 mpg consistent.

What I determined was that my original FPR allowed too much pressure when it got hot, but looked fine when it was cold. Expanding parts, seals going bad, whatever. So my checks on a cold engine didn't tell what was happening while I was driving.

In summary, if everything else checks out, or maybe before you check everything else out, make sure that your FPR is working correctly, at running temperature. I get 36 now without the vacuum tube hooked up and about 25 at idle with it connected and the engine is running great. I did drive around with my temporary in-line gauge zip-tied down to verify pressure.

A few odd facts - I can pull the tiny hose that pulls vacuum on the A/C canister and notice an increase in idle speed, it's that sensitive to leaks. If I pull the oil cap off it dies.

The Aeromotive regulators will not hold pressure after the pump turns off. It is documented in the instructions that come with it. The valve inside is just a steel ball on an aluminum seat, no polymer seal. (As a result, my engine, with the stock looped fuel rail, takes a few seconds to fill and repressurize the the rail before starting. With the old (bad) FPR it would hold pressure and start right up.)

One more thing - Months ago, I had the typical warm start problem, where the car is hard to start then runs like dirt for about 10 seconds, back when I had a set of injectors going bad. I put six new BWD injectors in and that problem is completely gone. In retrospect, it seems like the old injectors might have been flooding the manifold with gas, as they leaked out. Just a guess.

Finally, for what it's worth, the liquid-filled pressure gauges can be heat sensitive and will read incorrectly. It is documented around the net. So be careful where you mount it if you get one.

Sorry for the novel - just wanted to get it all out there...

Edited September 23, 2010 by Zed Head

[Zed Head]

Full disclosure - I have a different name over on Hybridz. I was never a forum person until I got this car. I originally signed up just to see the pictures.

Here is a related post by me on the same topic over at Hybridz - http://forums.hybridz.org/index.php/topic/94554-aeromotive-fpr-and-liquid-filled-pressure-gauges-underhood-heat-durability/page__p__890204__fromsearch__1#entry890204

Tony D had some good advice on gauges.

[mlc240z]

Amazon has a Sunex 30mm crows foot for $5.

Never heard of the brand, don't know it's quality, but I doubt for the price it's 'industrial' grade.

But it might be enough to do the job and throw away.

[FastWoman]

Never mind!

So I got this idea: Take off the heat shield around the master brake cylinder, and put a 12" Crescent wrench on the nut. There's just enough room to place it around the brake lines. (Yikes!) Then tie a rope through the hole in the end of the wrench's handle (a bowlin knot, of course). Wrap the other end of the rope around the end of the intake near the throttle body. Snug up the rope tightly, and then pull the length of rope upwards. The mechanical advantage on the wrench is enormous, and the pull is smooth and controlled. It worked. The nut came loose. Of course I had been soaking the nut for days with solvents and then hit it with a blow torch before trying to loosen it.

That having been done, I removed the remaining nuts/bolts on my intake and successfully removed it with not a single broken stud. I also removed several bolts on the exhaust. Having gotten the intake off, I gave all the remaining exhaust bolts another good soaking, and I'll try pulling that manifold tomorrow. So far nothing broken! Yea! I'm feeling a bit more encouraged now.

[mlc240z]

With the PBlaster, it almost makes you 'confident' when tackling rusted fasteners.

Just be patient and soak for a few days and tap them to set up vibrations to help draw the solvent into the connection.

Only broke 2 bolts and they were body fasteners. Haven't snapped anything important on the suspension or the engine yet.

[Nazgul280]

Now that's some good thinking, FastWoman!

Don't even think about reusing those old manifold gaskets!! !

You'll be driving this Z before you know it.

[FastWoman]

Zedhead, thanks so much for the real world info! You've confirmed or reinforced a few of my suspicions (e.g. dribbly injectors, flooded manifold) and have pointed me to things I hadn't even considered (FPR running differently hot vs. cold). I have two stock FPRs -- the one from my car and one I pulled off of an '81 ZX intake (a gift from Geezer). They are a few PSI off from each other. I think Geezer's is probably more accurate, and mine is probably low. Anyway, this tells me that at least one of them isn't quite right. Also thanks for the great info on fuel pressure gauges. I might look for an electric one. I hope they're not too pricey.

I'm not bothered that the Aeromotive FPR won't hold pressure after shutdown. I've gotten into the habit of priming before starting anyway. I actually installed a switch to do that. I did the same thing on our carbureted powerboat, putting an electric fuel pump inline just for that purpose. (BTW, the powerboat is my other project that's in a million pieces -- leaking intake and exhaust manifold gaskets and a carb that needs attention. Now THAT project is great fun regarding rust. It has a saltwater-cooled 318 inboard. The Z is easy by comparison. )

I forgot to mention yesterday that the underside of the intake manifold gasket (i.e. the side nearer to the exhaust) appeared to be rather degraded. The insides of my intake manifold are black with soot (is that normal?), and there are areas on the mating surfaces (manifold to head) where I don't have any identifiable gasket material and which are also covered in black soot. By comparison, other areas are pretty, clean, shiny aluminum. I guess that would qualify as a massive intake leak?

I also found a split in the boot between my AFM and throttle body. It's of course possible I put it there in the removal process. I had been terrified to remove the boot for inspection before (because it's old and fragile) but had run a mirror around it and was satisfied it was good. Anyway I do have an NOS spare for the reinstall, and I suppose I'll be buying another spare now. (Is there any aftermarket source for these things?)

Although I'm not there yet, I'll ask now: Is there any way I should treat the new intake/exhaust gasket? I've heard of people spraying them with copper spray. I have no idea what this does. The part is MSA's, if that makes any difference. Also I was planning to use liberal amounts of antisieze compound on the hardware. However, would the blue threadlock be better? Do I have to worry about the nuts/bolts backing off?

Finally, Bart, thanks for finding the crow's foot on Amazon for me! Although I no longer need a 30mm crow's foot, I wouldn't mind having crow's feet for use on the propeller shaft stuffing boxes on our two boats. There's almost no working space down there. In fact when working on the stuffing box on the sailboat, I have to fling myself over the top of the engine and almost hang upside down. It's not a pretty sight!

[FastWoman]

Oh, also... I remember seeing a set of stainless screws and bolts for the Z. Where would I have seen that? I'm starting to think it would be a very good idea to buy it before reassembling all this stuff!

Update: I've found zcarcreations.com, but they appear not to be in business anymore (no ebay auctions, no prices quoted). I have an email out to them.

Another update 9/25: I found www.boltdepot.com, which sells SS fastener assortments. I bought about $150 worth of metric SS screws, bolts, nuts, washers, etc. We'll see how far that goes.

Edited September 25, 2010 by FastWoman

[FastWoman]

Yikes! No WAY can I afford an electronic gauge! Oh well... Mechanical it is...

[Z train]

Fastchick:

Intake gasket just clean will do.If you want,you can use copper Permatex arouind the exhaust ports.-

Anti-seize-is a good idea.

The boots are still a dealer item as of July.

No loctite on the manifold bolts.

[FastWoman]

Thanks, Zdude!

I didn't have a name for the spray. Now, with a name, I was able to look it up and see what it does. It certainly sounds worth doing, both on the Z and on our powerboat (which is also lying in pieces).

Antisieze it is -- lots of it!