Leave the manifolds on, like others have said. it'll add 30lb to each head, but it gives you a handle to use for leverage to break the seal on the HG to get the head off.
once you have the head off the car, you can remove the exhaust mani.

If you're going to pull the timing assembly again, you can replace the oil pump gear. othewise I wouldn't worry about it. lifter tick on startup is a 'normal' thing with a higher mileage VG. once you clean out the heads, that should help. the big issue is that the aging lifters leak down while the engine is off and it takes a bit of oil pressure at startup to pump them up again. VEs are the same way.
You can spend about $350 and replace them all while you have the heads out, or you can deal with a few clacks at startup.

 

Status after working two 3-4 hour days this weekend:

Still need to remove the distributor, disconnect the y-pipe, and remove the valve covers. Then I can start removing the head bolts. Getting there...

I also have a laundry list of various parts that need replacing. Old cars can really nickel and dime you...

 

I would follow the head bolt tightening/loosening guide if you have one. Should help prevent any contortions in shape and overall flatness of the mating surface............. My mechanic friend, whom I trust with when he advises me, told me he only busts out the torque wrench for heads and also the manual for proper reference. Other wise get everything, as he says, in German spec: "gutentite".

 

What he said. follow the FSM procedures when removing the cams and the head bolts and when reassembling the timing belt stuff, but otherwise torque specs don't really matter on much else.

 

So very close! After working in the hour or two of daylight I have after work each day, I am now at the point where I can start pulling the heads. I hope to be done by the end of the day, but we'll see...

 

I got a question for you guys:

Does the oil pressure sensor (located below the oil filter) have the wire integrated into it (part of it) or is there a plug on the end of it. I managed to break the plug that goes into the wiring harness off of it during the disassembly process, and I need to know if I need to buy a replacement sensor or if the wiring is separate. It's kind of hard to see it without removing it...

 

wiring/connector is separate from the sensor. I believe there are two oil sensors, one with a boot, and one with a button (kinda like the ground on the dizzy). but both have connectors, and have no wire by themselves.
(hope that made sense, still haven't had enough coffee!)

 

Thanks, I will be putting in a big order to Courtesy here shortly...I need to replace 6 of those big, custom-bent rubber hoses (mostly for ventilation) that happen to be around $20 a pop.

The only thing I wasn't able to find on their site was that connector. I guess I will have to call them on it.

 

they'll probably charge you out the azz for it. i have one or two extras.

 

Or, if you don't anticipate having everything 100% OEM, you could find some other plugs, possibly from on of us with spare stuff laying around, and frankenstein the circuit. Better yet, holler at caped, who wasn't clear on what he has an extra one or two of?

 

Don't call Courtesy. Call Dave Burnette at Southpoint. more intelligent, nicer, and better customer service.

 

lulz

the harness wire for the oil pressure switch.

i might have one or two extra of some other things too

 

I have the front cylinder head all but off of the car, but I came across a bit of an issue...I took a pic of it, but my camera cord is at work, so I will do my best to describe it:

The two rocker shafts on each bank have areas cut out of them so the head bolts can be installed / removed. The intake rocker shaft (top one on the front bank) has two areas cut away (for bolts labeled "10" and "11" in the FSM) that are cut quite a bit deeper than the rest of cut-aways.

I backed out the bolts, but the heads of the bolts are too big and interfere with the rocker shaft. I cannot remove them. I was alone in the shop, so tomorrow I will try and remove the head once my friend show up to give me a hand. I am not sure whether the bolts are backed out far enough to be disengaged from the block.

If I can't get the head off, will it do any damage to unbolt the rocker shaft to try and get some more clearance? The rocker arms sit over the shaft, so I am not sure how much they would move, but will doing this knock anything out of adjustment?

 

The cut away areas are plain as day in this pic from rockauto.com

For whatever reason, the bolts will not clear the rocker shaft. Not sure if this is relevant to the problem, but I set the timing at TDC before getting started.

 

make sure you have the right shaft pointing the right direction. one has deep recesses for the bolts, one has shallow.

http://www.nicoclub.com/FSM/maxima/1994/em.pdf page EM-19

 

I haven't touched it. The only thing I have done with the head is remove the valve covers and the head bolts. Did you read what all I posted above?

 

IIRC, you should have nothing to worry about, you can pull them off after getting the bolts as high as allowed by the shafts. You can remove the shaft to make everything smooth and easy, just loosen it slowly by breaking each bolt, starting in the middle and moving outward in a circular pattern, so all are evenly loosened, and only loosen in progressively increasing increments (don't pull the middle bolt all the way out, then the next, and so on; only give each a 1/2 turn the first cycle, then 2 full turns, and so on). I didn't pull off the rocker arm shafts when I pulled my heads, but naturally be aware of this when you reinstall, if you don't want to have to knock the bolt past the rocker arm shaft, then insert those prior to head re-installation. The timing is a good thing to have set for the crank, but the timing is easily reset, and should be unless you want to fight the springs, on the cams if you mark which direction the alignment pin, on the sprocket to cam mating surface, is directed. Hope this helps, have fun!

 

o nvm

try taking the rocker shafts off then just arrange them so it's easy to put them back where they came out of. no need to touch the thingy with the lifters in it, just the shaft/rockers.

 

Thanks for the info...Interesting that Nissan would make enough room to fit a hex socket in to get at these bolts, but not enough to pull them out.

That being the case, if they are backed out enough to get the head off, I will just leave them in place and tell the machine shop to make sure they put them back in when they slap everything back together.

 

Yup.. basically back them out as far as you can, then pop the head loose. If the bolts aren't all the way out of the block, then hold the head off the block a bit and continue removing the bolts.
I vaguely remember pulling the heads off my VGs without that problem though. strange. :shrug:

 

interesting... all this time, I thought head bolts needed to be replaced when removing/installing heads... I guess I should stop thinking and start reading...

is there a section that says when to replace them? I must be missing it.

 

I have encountered sources which live by that rule Ben, but I didn't follow it, nor did my machinist say it mattered; but my heads weren't warped, so perhaps if they see that your head is not flat, then you would probably want new bolts b/c the old ones may be mishapen......... I am unsure if all of that is 100% true, but makes sense to me......

 

Heads are off of the car and at the shop. It was a lot of work to remove them, but it should be worth it in the end...

 

What shop did you send them to?

 

Kent Machine & Engine Shop

 

You got awesome timing and execution! Right on time! Wish all my projects handled with promptness.....

 

I went over to the garage where my car is today to do a bit of clean up and to oil the cylinder walls to prevent corrosion. I was in a hurry the other day to get the heads to the machine shop and didn't take a close look at the tops of the pistons.

Cylinders 3 and 4 (the middle ones on each bank) both have a small indentation in them from where the intake valve hit. I ran my finger over both of these marks and the edges are smooth (no burs). I don't think that it will affect anything when I put it back together, but I figure I'd post my findings and ask for some feedback, just in case...

 

No thoughts on this???

 

My front head intake valves slapped the crap out of the pistons, leaving only a "fresh metal" color, no indentations, and I am willing to bet, if anything is bent out of shape, it would only be the valves that are hurt. I wouldn't worry about the pistons, they are pretty tough, in comparison to the valves, and you should know what condition they are in from the machine shop before too long. Mine actually were in great shape, even after the warfare they went through, the shop replaced the seals, gave em a bit of grinding to get all the deposits off, and now they are in use.

 

Ben, you're good to go!

 

I don't know why, but I was under the impression you were going to be posting pics. But if it gets in the way of you working nm.

 

I have a few pics, but I wasn't able to find my camera cord for a few days...I found it as I was frantically doing my final packing for my work-related trip to Africa. I will post up some pics as soon as I get back to the states. I am currently in an office at a rig camp in near the southern border of Chad.

I really hope this car is good to go for a LONG time after all of this is over. I put in a new P/S pump, new radiator, fresh timing belt / tensioner before this happened.

It will be getting a host of new dealer only hoses (pricey!) and some various other odds and ends as I put it back together.

As soon as I feel it is running like it should, out comes the transmission for a new input shaft bearing. It will practically have a brand new drivetrain when I am done with it.

 

Quick question for y'all:

There are two check-valve type items that screw onto the back of the upper intake manifold. One is a PCV valve. What is the other one called?

 

The other large screw-in port fitting is for the brake booster...vacuum hose.

 

What he said. (holy ****! We agree on something!)

 

The planets were all lined up apparently and all the solar systems.....

 

replace engine with dohc engine or buy a new car imo.

 

Thanks for contributing to this thread...

 

Strike one, deutschbag.

 

Ouch! I just ordered $219 worth of OEM rubber hoses / misc rubber parts from the dealer. This is one of my biggest issues with old cars...Rubber just doesn't last forever.

Add that to the $480 for a valve job and new gasket set and I am at ~$700 not including the cost to refill it with coolant and oil and the other misc costs along the way.

I will post some pics of the project sooner or later when I get a chance...