sewebster

I couldn't find this air relief plug... should my 91 have it?

I'm not entirely sure what you are asking... I know that the AAC valve is basically fully underneath the upper intake plenum, and there is a connector that attaches to it, comes in from the back.

Replacing the rear shocks is really easy, just unbolt the old ones and bolt the new ones in. Basically the same with the front, except the stock system uses a vertical stud on the top, and some aftermarket shocks don't have that.

You mean leaking past the rings? But won't it be stopped by the closed intake valve (I guess it could be leaking).

Didn't notice that in your other thread before. Thanks.

How does the gas get into the oil from the injectors?

I think the little thing that plugs into the prong on the top/side of the distributor is just a ground. The large plug is the crank angle sensor...

A properly rebuilt engine is a different thing than a used one... of course, a used engine could be great, or not... As I've discovered though, properly rebuilding an engine is quite expensive, so you could likely buy several used engines if you had to I believe you can buy a rebuilt engine on RockAuto for about $2000. I'm not sure how good a job they do.

Interesting. Well, my cams are 240. So perhaps I'm just the one with strange cams, but I have seen a bunch of other 240 cams as well (and a lot of 260).

Sorry to hear that Good luck!

Ok, so in my manual (91) on pages EM-26 and EM-54 it has the same specs: Standard cam lobe total eight (all the way across the cam) is 1.5566-1.5641". The wear limit is 5.9 thou. I measured my old cam and it is 1.5377 total (note this is a lot lower than the spec, way more than could be wear IMHO, they don't look that bad). The measurement across the perpendicular is 1.3008". Those measurements probably aren't accurate to tenths because I didn't spend enough time setting it up to make sure I measured exactly the right spot. Anyway, the difference is 0.2369". This is the "240" thou lift that the shop was talking about. I haven't seen any cams with 393 lift. Do some people specify the valve opening range? Because it looks like the rocker arm is 3:2, so with my cams the valves will open 0.360". A bit of a mystery...

Well, the valves were all rusted. The one that was stuck was pretty terrible. Had to drive it out with a hammer (and some wood). Apparently the shop that did the valves did not lube them, and I didn't either. Cool. Likely it wouldn't have actually been a problem if I hadn't ruined the cams right after and then let the engine sit for weeks. Anyway, thankfully, based on my experience and some measurements, the engine is only interference on the intake side, so there were no big problems. Cleaned up all the rust and re-lapped and I'll hopefully put it all back together tomorrow.

I think it's pretty easy to do the thermostat. drain radiator, remove fan and shroud, pull off lower hose, open thermostat housing? Maybe you need to remove the power steering belt?

I did the leakdown... so some of my valves are leaking, especially on the passenger side. I get leakages from 7-15%. But the engine was cold and the rings aren't fully seated yet. I assume that even with a cold and not broken in engine you expect the valves to fully seal? Some of them did... Guess I'm pulling the heads today.

The FSM has resistance specs for the sender (you replaced the right one, right, not the sensor with the bigger plug?). So you can put it in a pot of water with a thermometer and check to see if the sender is working. But it does seem weird that both would have the same problem. Mine does run a bit low though too (resistance is a bit off).

Hmm. They're still in the 2010 catalogue. So are the euro cams, which say they are 264 degree duration, so maybe that's the answer to my other question. Maybe you can't get them, in which case, they should remove them from the catalogue..

Hmm. The guy was measuring the "240" and "260" with a dial indicator, rotating the cam on his measurement setup. I just assumed he meant thou. I'll look up the manual tonight, but I assume it's the same page as yours. We can check to see if we have the same numbers I guess. It's too bad they don't tell you the stock lift, or stock "on on the actual lobe" diameter.

The connecting rods are what attach the pistons to the crankshaft. The "rod caps" are the pieces that bolt around the "bottom" half of the crank shaft and hold the rods on. They should be tight and should not wiggle around when you push on them. There is likely a specification for maximum play in the FSM.

So other than engine problems, how else do they die? Old age where all the catalyst gets used up? It seems to me that that would happen very slowly and a change from passing with flying colours to failing with twice over the limit would not happen in one year.

don't cats generally fail because of engine problems?

I would think that it MIGHT be possible to make it work somehow, but you'd need to be installing a bunch of isolating diodes etc. so you can insure that the alternators can't interact with each other etc. Probably not recommended unless you have a good handle on electronics!

I think you need to have a good hard look at the parts diagram and figure out what isn't moving that should be, and then make it move, possibly by pounding it out. You want to be "careful" so you don't damage stuff you don't need to. But if you've had a failure and that's what's sticking stuff up, then you've got damage already and you need to get it apart. Certainly you don't need to worry about damaging your old bearings. My 2 cents...

Since I replaced my cams just recently, I've been measuring a bunch of camshafts. The FSM lists a "standard height" for the cam lobes and gives a wear limit. All the cams I was measuring were way below the wear limit, even the new ones I got, which I thought was a bit weird. Now, the total height isn't really the important quantity, what you really want is the lift. I was at the local cam shop (Shadbolt Cams in Vancouver) and the guy there said that there were two cam lifts available for this cam, 0.240" and 0.260", with the 260 version being more popular. Mine were 240, and all the ones I measured from a Pathfinder were 240. He seemed to think that the lower lift was likely more appropriate for a truck since top end power wasn't necessarily what we needed, and maybe saving some gas wouldn't be a bad thing either. So is the FSM just wrong, and maybe giving the standard height for the 260 cams? Maybe some Pathfinders actually have those cams? Probably this is a bit of an obscure topic, and I already have the cams installed now, but I'm just a bit curious about this. I wonder what the lift on the "euro" cams is.

Part of the problem is that without some controlled tests, or information about formulations etc (which are presumably all secret) all we end up with is a bunch of anecdotes, which, I think, have limited value. Of course, there's no problem with people posting their preferences etc, and maybe readers can glean something from the thread. Looking at the similar "filter wars" topic, one way that actual knowledge was gained was by people cutting open filters and having a look inside. That information allows you to make reasonable decisions on what kind of filter you want to use. Ideally we'd find an analogous sort of "test" for oil. So maybe if people have links to comparative oil test etc. they could post those.

Anyone tried the Nismo springs in their catalogue? Maybe they are ludicrous expensive... apparently 1" lift.