Slartibartfast

I've worked on brakes before, and it's usually gone alright (except when I stripped a bleeder on a friend's van), which makes it that much worse that this one's kicking my ass. I swapped both front lines for the lines I had on it before. Pedal still sucks. Thinking about it, the rise I got in the pedal from clamping the lines was probably just because fluid wasn't going into the calipers. I tried blocking off both front ports on the master, thinking that surely this would make enough pressure to make the prop valve engage the rears. It did not. I reconnected the left front and disconnected the rears (I'm bleeding the connections at the master each time I open one) in case the rear circuit was the problem and the pedal still sucks. I'm back to staring at the master, booster, and pedal box. Can't find anything wrong with the pedal box, but the pedal does have an odd little pop when I'm pressing it down, like there's something wrong with the pivot, or like something's catching. I can't see anything wrong from the footwell. Master, well, it's master #4, so on that alone I'm inclined to say it's not that, even though the symptoms seem like the master's all it can be. The booster felt fine when I tested it with the angle iron but with the weird pedal feel I can't shake the suspicion that something's gone wrong inside, some plastic ball end has split or something, and it's limiting travel or something. Also, disregard how I thought the prop valve works. If it worked like that, two-man bleeding wouldn't work on the rear brakes. So, yeah, I have no idea how it works at this point, which is really not helping me diagnose this pig.

Looking back at it, I got a hard pedal from installing the master with all its bleed plugs in (I misremembered this later, apparently) and then again more recently with a piece of angle iron across the front of the booster in place of the master to rule that out. Brute force is right. I'm tired of thinking about this mess right now but I'll see if I can get a blow-by-blow together soon if the next thing I'm going to try doesn't fix it. Today I opened up the drum master I had on the bench (because what else was I gonna do with it) and think I figured out the prop valve. Fluid pressure from the front brake piston (teed off from where the front brake lines connect) presses a plunger, opening the prop valve and allowing pressure from the rear piston to flow into the rear brake system. The rear brake piston is not solidly linked to the front piston (there's a spring in between them), so the front brakes move with the pedal, and the pressure developed in the front circuit (not necessarily the travel of the front piston) determines how much fluid passes into the rear circuit. This tells me two things. First, it tells me that a hydraulic failure in the front brake circuit would also take out the rear brakes. Second, it tells me I've got a hydraulic failure in the front brake circuit. It's building pressure, but not enough to open the prop valve. Something is compressing (air in a caliper) or ballooning (bad soft lines). I ruled out the front lines before because both squirmed the same amount under brake force and neither had any obvious damage. Clamping off the right front line (which would isolate a bad caliper) has no effect on the pedal. Clamping both front lines close to the top raised the pedal about an inch! I hadn't considered the possibility that both of them were junk straight out of the box. I'm considering it pretty hard right now.

Try tightening the brass screws on the back of the cluster. Seems to be a common cause of tach problems, might be confusing the speedo too.

Wow! That's nasty. Looks like something laid eggs in there! Hopefully the new one works out.

Proper two-man bleeding didn't magically fix it. Passenger's front bleeder made a noise like it was passing lots of air but only the smallest of bubbles were coming out, at least as far as I could see. We bled that one for quite a while and it still made weird noises (along with the one or two tiny bubbles per pump). Finally I said screw it and reverse-bled that one, assuming air was caught in the line where it crosses the firewall and was rising between pumps. My dad watched the master and saw that a lot of clear fluid and a couple of very small bubbles came out. Didn't change anything, of course. Swapped the stock caliper onto the driver's front again because neither of us liked how floppy the reman was, but, again, no change. Rears still get bugger-all pressure but bleed just fine. No signs of damaged lines or swelling hoses. Given the garbage that came out of the right front caliper the first few times I bled it, and the weird bleed issues with it now, and how the brakes went to crap when I replaced the front calipers, we're thinking that caliper may be junk (and the prop valve's trying to compensate). I never tried putting the old one back on, and I'd sent it off by the time I realized something was wrong with the brakes. I replaced the front brake hoses shortly before doing the calipers, so for all I know, it could be one of them (though, again, I don't feel anything out of the ordinary with them). I still have the front hoses that were on it before and may test it with those quickly before laying money down for a caliper.

I don't think there are any damaged lines (barely any rust on this truck and no obvious loss of fluid or wet spots) but I'll check again for kinks etc when I'm under it tomorrow.

Yeah, with the rear line clamped off, the brakes still suck. Given that the brake master in my '95 leaked in the same place, and the newest factory one I'd find at the wreckers would be the same age as that one, I'm leery of getting a used one. New from Nissan is $260. I would just rebuild the factory MC (it looks brand new inside) but Nissan wants $80 for the piston kit. I also can't believe at this point that every master cylinder I've tried to install was trash right out of the box. It sounds like most guys just throw one in and they're good to go. I'm running out of ideas too!

Soft lines are fine. No ballooning. My dad's theory is that the prop valve built into the master is screwed up and it's bypassing fluid that should be going to the rear brakes back into the res. Apparently the wrong bleed order can kick in some kind of safety feature where the valve shuts off fluid to the line it thinks is breached. This could explain why the first MC I tried to put on locked up and wouldn't even drip fluid out of the connection for the rear brakes. I would not be surprised if my attempts at gravity-bleeding (and certainly the reverse-bleed I tried) confused the hell out of this valve, and I also don't know that the mechanic knew Nissan's ass-backwards bleed order when he installed the master that's on it now. We're going to two-man bleed the SOB this weekend, in the proper order, and see if that gets us anywhere.

I unbolted the master, slipped a piece of angle in there to block the pushrod (with a washer welded in the middle so the rod couldn't slip sideways), and bolted that into the master's place. The pedal's got a little free play (opening the vac valve in the booster, I'm guessing) and then it's hard as a rock. No squish at all. That rules out the booster rods flopping around. Maybe the rod is adjusted wrong and it isn't hitting the master, but I think I checked that before, and I can't imagine how it would've adjusted itself. (I guess something could've broken out from behind the rod, but I didn't hear anything rattling around inside when I shook the booster.) If I assume the master's good (and how the hell could I have gotten four duds in a row), this calls my previous tests into question. Maybe the bleed plugs aren't meant to handle full braking force and leaked enough to perfectly imitated a fault elsewhere. Next step is to re-check the soft lines. Maybe the mechanic's onto something.

Got my truck back. Mechanic's best guess at this point is a bad soft line to the rear axle. I can see his reasoning, but if that line was the problem, the pedal should've firmed up when I deadheaded the system at the ABS block, or when I had the master plugged off. Tonight I'm going to make a block-off plate to bolt to the booster where the MC is now. If the rod has nowhere to go, and the pedal still goes squish, I'm calling the wreckers tomorrow to see what they want for a booster.

Sounds like you might have a vacuum leak between one of the injectors and the manifold.

Good thing you found that out before putting it back together!

Mechanic replaced the brand-new MC with another one. Changed nothing. There's a shock. It's not the master. It's not any of the hydraulic system from the master down because the pedal acted the exact same with all three ports plugged off. That leaves the booster and the brake pedal itself, and I think I'd notice if the pedal pivot was tearing off the firewall or something. I don't know why the fronts are getting pressure while the rears aren't. My best guess there is that the prop valve is sealing off the rear brakes because there isn't enough fluid moving to work all four. My guess for why there isn't enough fluid moving is that one of the pushrods in the booster has come out of its cup (or whatever's supposed to retain it) and is being forced sideways instead of extending out and pushing the master pistons like it's supposed to. This is of course a wild-ass guess. I have no idea how the prop valve works and I've never cut a brake booster open to see if what I suspect is even possible. At this point, though, I'm just about out of things it could be. I'm also remembering an odd noise I heard at some point during the bleeding process that sounded sorta like a fork flopping around in a can. I was not able to replicate the noise, so I didn't think much of it at the time, but now I suspect it might've been the sound of a pushrod striking out on its own.

HA-175 of the '03 manual shows the clutch coming off with just the one bolt in the middle of the clutch plate (they also show a special puller tool to pull the pate off of the clutch) and then a snap ring behind that. I don't see any mention of the bearing, but that doesn't mean it's not possible to replace, only that Nissan didn't see the need to cover it. HA-18 has a cutaway of the compressor. It's not well labelled, and I've never been good at figuring out what's connected to what in cutaways, but it looks to me like there's a dual-race bearing retained to the front of the compressor housing by an external circlip. I assume this would be staring you in the face once you got the clutch off. Given that it's buggered already, what do you have to lose? Take it off, see if you can get into it. If you can get that bearing off, maybe it's got a part number, or you can find a replacement by dimensions.

What damage would oil have done to the VG33 heads? IIRC someone on here used VG30 heads an a VG33 block because they thought it would be easier than swapping the VG30 cams into the VG30 heads. The passages aren't the same and I think they ended up doing some grinding to sorta fudge the difference. Not the way I'd go. I haven't heard of any timing differences between the two motors, except that your '89 VG30 will have square-tooth sprockets and the VG33 will be round-tooth. Make sure all the sprockets (and the belt!) are the same style.

My dad's '03 had the same consumption rate. New PCV valve didn't change anything. No signs of an external leak. Smoked like hell on hot starts, never any other time, still pulled like nothing was wrong. He couldn't find a wrecking yard motor with even compression so he sold it to a guy who had a wrecked one with a rebuilt motor and bought a Toyota. This guy says the engines were built with too much taper in the bores. I've also heard of power valve screws falling in and potentially chewing stuff up. My dad and I suspected valve seal issues on his due to the hot start smoke but he got rid of it running rather than tearing into it.

Theexbrit made a Jeep bumper fit his. Tactical Armor Group made one, not sure if they're still around. Hawairish is working on a kit. Lots of custom builds out there too!

Some good info in here about different options. There was a one-year-only Canadian balancer that would bolt on but it sounds like they're very hard to find. I think some guys just run VG33 accessories with a serp rather than going to all that trouble for V-belts.

Good to hear! And good to know Nissan found another random thing to change mid-year.

Seems suspect to me too, but it's either the master or the booster, and it's a bizarre failure from either component. I am increasingly suspicious of the booster.

Cheap fix for the win!

Mechanic says he's ruled out everything but the master cylinder, so he's replacing that again.

I know the blower resistors in the WDs get hot enough that they can start fires if the HVAC box is full of leaves and crap. Not surprising yours got hot, but odd that it let the smoke out that quickly. Blower motor spins freely? And yes, if a resistor burned out, that'll prevent power from reaching the motor on that speed. (If it's set up to use the resistors in series, one smoked one could take out multiple speeds.) Basically the resistor module has a few different resistors in it and the HVAC can send power through any of them to the blower motor. Send power through a high-ohm resistor and the blower turns slowly; send power through a low-ohm resistor and the blower spins faster. Max speed should bypass the resistors entirely, though I don't know that for sure on the R50. Hope your fingers are alright. I was reminded once that everything's a fuse at some amperage when I vaporized a paper clip while holding it with my fingers. That one took a while to heal.

1. The stock "sad eye" lights on the Hardbody pickups are the same as the Pathfinder lights AFAIK. If you convert your front end to the smaller rounded rectangle headlights some HBs used (more options available because it's a size used by many other vehicles), you'll need the buckets and grille to match (I think the corner lights are different too). You can also get clear turn signal lenses and corner lights if that's your bag. I haven't seen aftermarket tail lights for these (and no, the HB ones won't fit) but I have seen guys put slotted covers or spray-tint over them to make them less effective. 2. At least one guy I'm aware of has cracked the ECU and figured out how to get a little more power out of it. He's on the NPORA Facebook page. 3. VG33 swap with the cams and intake from the 3.0 (swapping the intake means the electrical system just plugs in and the ECU's none the wiser) is common and pretty well documented here. So is auto to manual swapping. If you want to go crazy and have the resources, you can build the hell out of a VG, turbo what's there, or swap in something completely different. V8Path managed to squeeze a Chevy V8 into his. 4. Unless somebody's been into it before, you have the VG30E. VG is the engine family, 3.0 is the displacement (roughly), E means multiport injection. There's a lot of good info in old threads on here. I usually just google "NPORA ..." with whatever I'm looking for rather than bothering with the forum search feature. Many pictures are dead, unfortunately, but there's apparently a browser extension that'll get you around some of that.

After reading about guys having their synchros drain out as glitter in the trans fluid, I'd play it safe and find a straight GL-4 fluid. The issue apparently is an anti-wear additive that works great for hardened steel gears but is hard on the softer metals used for the synchros. GL-5 has about twice as much of this vs GL-4. So, yes, it meets or exceeds the additive spec of GL-4, in the same way that straight Everclear meets or exceeds the alcohol content of a rum and Coke. I assume you've read the TSB for over-filling as well.