sewebster

Why didn't they just put slightly bigger cutouts in the pistons to get rid of this problem? Interference engines frustrate me, but probably I just don't understand the rationale... From my measurements the VG30 is barely interference... only the intake valves would hit, and then not by much.

Just thought I'd post an update on what I did a few months ago... I drilled and tapped the holes for M10x1.5 and just used easily available BOLTS, instead of studs. This has been working fine. I upped the torque a little based on my calculations for achieving the same tension as with the M8 studs (calculations online if you search and are willing to do some math). I think I used about 20 ft-lbs but I am not certain I remember right now. Anyway, bolts aren't really ideal, because every time you take them out and put them in you are putting wear on the threads in the heads, and now, especially since I've already drilled the holes larger, I am probably getting close to cooling channels. However, I have found that with the studs, the studs themselves always seem to come out instead of the nuts coming off, so really you end up with the same problem. Ideally I guess you'd have interference fit studs so that they would be less likely to come out, with anti-seize on the nuts, but I don't think the VG33 studs are interference? Anyway, just throwing this out there as an option that seems to work, and is easy and cheap to get the tap and bolts (watch the length). But there are no warranties supplied with this advice!!!

Yep, you can check with the timing cover off, or also by sticking something in the #1 spark plug hole.

I assume you mean .628 since .68 wouldn't even fit in the guide plate. There are certainly mechanical micrometers that read to tenths, the last digit is on a vernier scale. Anyway, could be some other seizing problem I guess... is the guide plate hole way oversize? The damage looks like the lifter is not going up when it is supposed to and is grinding against the cam lobe...

Looks like those lifters and that cam is toast. Looks exactly like what happened to me with oversize lifters. The spec is 0.6278 to 0.6282. Mine were like 0.629 if I recall correctly. Measure again, very carefully with a mic that is good to tenths?

Installed a missing timing cover screw, replaced an exhaust gasket. So much quieter now, we'll see how long it lasts!

Well, I started by buying the most expensive ones RockAuto had, and still got screwed... Old lifters would probably still work, but if your cams are ruined then you still need to replace those. The lifters I got that were eventually good were Clevite brand I think. I had problems with Sealed Power and Beck Arnley.

Maybe you had the same problem I did. Oversize lifters seizing in the guide plate. I had to buy three sets of lifters before I got ones that weren't too big. Mic them!

While the lifters can "pump up" with oil and take out some slack, if all your components are in "like new" condition then there is no slack even with the engine off (for any cam position). I'm not sure on what exactly the lifters and cams are made of, but I think if you have significant wear on the lifter bottoms then the cams are going to be toast too unfortunately.

The auto hubs should lock in reverse, it's just that switching from forwards to reverse they need to unlock and then lock again, so if you are trying to rock or something then this isn't optimal because you might get the rear wheels spinning a bit before the fronts lock and you get full traction.

The rockers don't look fantastic, for sure, but they don't seem worn enough to cause the motion in your video? Do the three worn lifters correspond to the rockers that were loose? Pics of lifters? Compare height to good ones?

My understanding is that it is, from right to left, 30 BTDC, 25, 20, 15, 10, 5, 0 BTDC. So you put it on the middle mark. But however apparently there are a variety of pulleys out there. Mine is a 91.

You might be able to measure the cam height in situ, not sure, but small changes are supposed to be taken up by the lifters... I'd think you'd really be looking for fairly serious damage, like the cam looking all ground up. Happened to me when I had stuck lifters, was obvious. Also the bottom of the lifter was chewed up too. I've also had stuck valves, so the valve wasn't all the way up, causing slack in the system. Edit: the lifters would also expand to take up any minor wear in the rocker pads... (don't think there is any spec for those in the FSM). So again I think you're really looking for something pretty major and obvious with looseness like that. That's my take on it anyway.

If you hear "noises" but the crankshaft isn't actually turning then you may not be causing (much) damage, or, maybe your belt isn't even broken after all (but it dying suddenly and not restarting does sound like that). Take off the upper timing cover to check the belt. It should be pretty fast to do that...

Well, you've found the source of your noise! So now you need to figure out what the problem is. If it's assembled correctly, then you want to check: -lifter height? -worn cam lobes? -worn rocker shafts? -worn rocker inner diameter (on the shaft)? -worn rocker pads (where you contact the lifter and valve)? -valve height? Usually I'd say you could find the problem just by eye... comparing good to bad. The FSM has detailed measurement instructions for pretty much everything though.... but things are so loose in your video that you shouldn't need to actually measure... In terms of knowing it is assembled correctly... let me think. You need to have the lifter guide plates fully seated down on the locating pins. You need to have the rocker shafts on the right side (can you even mess this up?) The cutouts in the shafts should be over the cylinder head bolts. You need to correctly torque the rocker shaft bolts, but even just hand tight you likely wouldn't get that much movement.

Where'd you get a new lens by itself? I thought you could only get the whole assemblies for like $50 or more...

Obviously there are some downsides to autos with engagement delay and stuff, but I figure that since I haven't broken them yet, I might as well keep on using them until (if) they break and then replace them with manuals. Presumably when you guys say they break, it is a catastrophic thing where the brake plates bust or something and they don't work anymore right?

You want to pull the cable bundle out with it... if it is bolted onto the oil pan (as mine is) then disconnect that. Alternatively you can detach the bundle from the starter and get it out of the way first. I just took my starter out and found it to be pretty easy with no body lift, t-bars cranked 1". I did remove the front diff first though. Perhaps that makes it easier somehow. Also manual transmission, so no cooler lines.

I actually tried to take it apart on the weekend, but the screws on the cover plate (#3 phillips) were really tight. Not sure why since I just had it apart a couple months ago. Anyway, I measured all the clearances per the FSM when I had it apart, and it passed. However, I think the procedure is flawed. They have you measure stuff, including the clearance between the gears and a reference surface, such as an engineer's square. They don't have you measure the clearance between the gears and the cover plate (would be hard), which is what actually matters. My cover plate showed some wear, but I didn't think it was too bad. When I took the old pump out I covered the outlet (and the small hole on the bottom) and blew into the inlet. A lot of air leaked out between the gear and cover plate in the centre (where the crank goes). The new pump leaked much less there (still a bit since there is no real seal). Anyway, if you have your pump apart I'd be carefully evaluating the cover plate and also doing the "blow test." Interestingly, the new pump I bought from RockAuto (Sealed Power brand from Federal Mogul) is basically identical to my old one, except where the nissan logo was there are some grinding marks like someone removed them. So I guess it is from the same molds. Dealer pumps aren't super expensive, but it was going to be a couple weeks to get one.

Replaced the oil pump. Pressure seems to be good now! Hopefully it stays that way. I do recall seeing higher pressures right after oil changes before (fresh filter?). Anyway, fingers crossed...

It's a fairly hefty "tap" required to get the races in and out. For me it was more of a mental challenge than physical. You don't want to slip and score the race.

The pilot is a brass coloured bushing in my 91 5-speed. Seems unlikely to cause this sort of problem in my opinion.

Yeah FSM = factory service manual. I find having the paper copy handy, but you can download one from a link in the garage section somewhere. Highly recommended. I think if messing around with injectors is as bad as it gets, then you are pretty lucky My truck is sitting in a friends garage at the moment with the front diff on the floor, oil pan off, timing belt off, waiting for a new oil pump

I think the idle switch is part of the throttle position sensor? But I don't think the ECU actually uses the output for anything other than diagnostics. Talks about it in the FSM. MAF is a common problem that could explain your symptoms. Clean the sensor carefully and check the wiring (visually inspect and see if wiggling it does anything). Injector problems can be annoying. You could have leaking seals or a stuck injector etc. You could try the procedures in the FSM for some diagnosis, including unplugging injectors one at a time to see if each one is working (if you don't hear a change when you unplug one then that is bad) and pulling the distributor and rotating by hand to see if you hear an injector click at each 120 degrees. I might leave the knock sensor for now and see if the code goes away once you solve the rest of the stuff. It might be easier to just bypass it (with a resistor?) than deal with it as it is under the lower intake manifold.

I haven't done it yet, but probably just using a remote oil filter kit is the easiest way to solve this problem. There is a video in the howto section on setting it up.