Budman1

I'm starting a second inquiry on this runner, to address another bigger problem.....
1992 4Runner 3.0 vz 4x4......
i just bought this runner as a 'doa', parts doner for another 4Runner project.
PO sold because while driving it lost oil pressure and shut down, did not run hot, would not restart.
He towed it to his house and it sat there for several months, advertised for sale, I bought it, trailered it to my brothers garage.
then I started thinking, while he was driving,,,, it PROBABLY started dying, then he noticed the zero oil pressure and heat guage 'normal', MAYBE it will run!!!!!
With help from Dropzone and Charchee I found a code '12', connected a manual oil pressure gauge, changed fuel filter (ugg) replaced a fuse, reconnected the plug to the TPS and this thing runs.......runs great!!! Then the knock started, sounds like a stuck lifter (if it had one) maybe a stuck shim?? Then goes away......then comes back?????
So I'm asking advice, before I tear down to the cams looking for....... I don't know what?
Anyone have something similar, can a misfiring injector make this noise, what about the Cam Belt Tensioner?
Sincere thanks for the great advice I've received, and to any assistance you may have with this conundrum.
Bud

scope103

I suppose you could have a valve stuck in the valve guide -- but that would set the compression in that cylinder to zero. (So I'd start with a compression check.)

You could try a stethoscope (the tube inside a roll of paper towels works well) to localize the sound you hear. If in the top end, removing the valve covers to look for obvious damage in the cam/shims would not be difficult.

Budman1

Thanks Scope103, compression check makes sense

Budman1

Anyone had good reactions from adding upper lube or other chemicals?
Am I gonna have to tear it down to look at the cams?

scope103

Try to localize the noise first. Some problems with the cams are obvious, some obvious things are not problems (or the source of your noise) at all. Better to know first.

The cams are easy to see; it just depends on what "tear it down" means to you. You'll need to remove the plenum (upper intake manifold). It will be a little tricky the first time, but then you'll just breeze through it. (Take careful notes of where all the vacuum, etc. lines go. You don't want to be one of THOSE guys.) Then remove the valve covers and you're there. You'll want to replace the valve cover gaskets (a common leak source) and the plenum gasket; they often come in a set so get them ahead of time.

Budman1

I'm going to do a compression check first.....If that is good,,,,,well I'm just kicking a can round the yard, waiting to see if the 'miracle cure' shows up,
if not we go down to the cams.

toiyodah4WD

You can do the "flip method" with plenum: most of the hoses on passenger side remain connected. EGR stuff, and 1 or 2 hoses need to be removed. There are photos online showing how this looks. Actually, the engine block hoist bracket front passenger side of engine is a convenient,sturdy spot to rest the plenum on when you are checking cams or whatever. It may get in the way a bit on passenger side, but you can figure it out.

Budman1

Thanks Toiyodah4WD.....Great confidence building suggestion. I know 'I can', I sure don't want to

scope103

I've never done that method, but it is hard for me to understand how it would really help.

Obviously, with either method you'd have to disconnect the coolant lines to the throttle body, all three (if you have auto w/cruise ctl) throttle cables, the resonator hoses, the TPS and ground wires, and the vacuum lines to the TVV and the EGR (the EGR lines have to go to get to the plenum bolt). On the passenger side you'd need to remove the plenum stay and the egr tube to the exhaust manifold (at least). I don't think it would be possible to flip the plenum without disconnecting the PAIR input as well (short ~25mm hose) -- which for me is the hardest part of the whole effort. So what does that leave? About a dozen small-diameter hoses that are easy to pull off and put back on. You do need to write down where they go. But if you think you can avoid that by "flipping" the plenum, what do you do when a few lines pull loose on their own?

So I don't see any advantage to leaving any part of the plenum connected; just disconnect it and put it somewhere safe. But as I said, I've never seen the "flip" done.

Budman1

Sooooo.........here's the 'plan',,,,,,,,the absolutely,maybe,plan.....not Charchee approved yet
I'll add a can of seafoam to the crankcase, run the engine for a couple hours while I use my stethoscope, listening.. , then remove the spark plugs, do a compression check on all cylinders, hopefully may show problem area, assuming the problem hasn't disappeared, (even if the clacking stops I want to know). From there we formulate a new plan........ using the suggestions from Toiyodah4WD and Scope103 and Charchee if he finds us over here.....
Anyone else have reasonable ideas..chime in, I wanta quiet running, goyota
I'll start reading about 'how to post pics' next,

toiyodah4WD

"I hooked the fuel line up to the wrong port on the plenum..." There's a guy who just posted this and truck is running like hell, so for the novice like me and bud the simpler the better. Personally, I have a heck of a time removing and putting back hoses on "ports." I did finally get a good pair of pliers for the clamps. But anyway Scope knows what he's talking about, I'll give him that

Budman1

Toiyodah4WD, the pic in my avitar is the 3vz I've been building for 2 years for my '95 4Runner 2wd(pic on my page), didn't take that long, two-3 days a week, vacate a month....etc...I don't get in a hurry. I share a 30x40 garage with my brother and he is also doin stuff, we just rewired a '62 Econoline truck and got it running for him, and now it's time for the 4R. I got the 95 in pieces, orig motor gone, another to be rebuilt, no tubing, nothing to focus on for re installation. That's why when this '92 came available completely intact and affordable, I jumped on it....for the tubing, dizzy...things. Fast forward and the 92 is fixable, I think, if not I'll probably pull it and put the rebuild in it, then sell it for enough $ to finish the 95. I can rebuild another 3vz waiting for one to sell and still have something to show me how to put it back together. NOW, I'm tired after all that thinking and typing, but seriously, I'm excited too, I want to FINISH something!!!!

scope103

Get a hair dryer. Not only will you lose the bed-head, but old rubber gets very stiff. Warm it up first, and it is much easier to remove. (Particularly the big ones, like the PAIR hose.) Also, you reduce the chance of splitting (or just breaking) a hose.

Because I'm impatient (and I have naturally missing hair), I use a hot-air gun. But if you do that, remember that they can get hot enough to set rubber on fire. I put my hand on the hose when I'm heating it; if it's too hot for my hand, it's too hot for the rubber hose.

toiyodah4WD

Thanks for the tip.

Budman1

^^^^^^^^ I agree, great tip. I've got a hot air gun that I use for shrink wrap, I'll try it.

Budman1

I've removed the plenum, right bank(passenger side) valve cover and the top front timing belt cover.
First thing is the timing belt IDLER, between the two Cam gears, I can spin it by hand, shouldn't it be too tight to turn?
No irregularities noticeable yet, I'll pull the other valve cover and check valve clearances tamarra

Budman1

Changing out the Idler Pulley took out some of the noise, but.......methinks aRod may be wriggling.....may start pulling this engine Friday
I want to pull the engine and leave the transmission but read somewhere the heads needed to be pulled to unbolt the top bolts for the transmission, is that right?
I need to survey the simplest way to extract the 'bad' boy......Movinnnnn on

scope103

!!
With the timing belt on, you should NOT be able to turn the the No. 2 idler pulley. http://web.archive.org/web/201003261...67timingbe.pdf (or the No. 1, for that matter). If your timing belt is that loose, it could cause all sort of problems. The only way (that I can think of) that it could get that way is if the tensioner went bad (I'm 80% sure the '92 has the hydraulic tensioner; earlier models had a spring tensioner).

Budman1

This engine has the spring tensioner, my 95 had the hydraulic, i removed the Idler pulley and could hear metal scraping metal when I spun it in my hand. I replaced it with an extra used one in the shop, couldn't get to the spring tensioner without pulling the lower belt cover, someone got there first and the bolt was rounded Changing the pulley stopped the screeching and now the sound is much like a rod knocking, not horrible, but knocking......so, how long before it gets ugly and ruins the block? do I drive it awhile, finishing my other 3.0 or pull it now......I just happen to have a 3.0 crank, been turned 10/10, ready to run

Budman1

Can you tell.....I don't want to pull this engine
my latest efforts in evasion......pulled the plug wires individually while running, no change in noise, put runner in gear, pressed brake, applied gas....no change in noise.
i have NOT checked valve clearances, I have NOT checked compression.
what do y'all think?????