Changing oil pan gasket on L28e(t) with engine in car

[supernova_6969]

Hey guys. 

You might know me from other, silly posts about air intake temps and insulating intercooler pipes (probably not though, these weren't THAT interesting). 

 

quick background: I bought a 1983zx that had been modified by the previous owner: L28E with a turbo bolted on, and a megasquirt II for ECU.  overall good condition but it ran rough.  The guy tells me (me, who is willing and able, but not all that knowledgeable) that all it need is a good tunning via the ECU;  he told me he'd build it, tuned it perfectly, then took it apart and rebuilt it so it would be able to tolerate more boost and make more power, but then never re-tuned it, thus the roughness.  

 

Long story short, one year later, yes the tune was rough, but the mechanical needs a bit of love too: the plug wires were shot, I suspect the injectors aren't all working properly, and it leaks oil enough that it's a bother, there is oil EVERYWHERE under the car (oil pan, alternator, crossmember, tranny, and everything all the way to the diff (I suspect maybe the tranny leaks or something, since there is so much all the way back there). 

 

I need to change the oil badly (am slightly over the 5000kms) and figured I'd fix the leak. I was convinced that the leak was from the oil pan gasket, so a few days ago, while under the car welding new bits of floor (small holes, nothing to write home about), I cleaned everything up that  was under the engine: oil pan, crossmember, and tranny.

 

Today, I super-Jacked the car (front on block that are on ramps, and rear jaket up on stands), and checked it all out after having rune the engine about 5-7 minutes.  here are the results:

 

Driver side of the engine/pan was squeaky clean (well not squeaky.  looks dry enough that it wouldn't squeak if it's life depended on it):

 

the passenger side, around the gasket was wet at the front and the back.  you can actually see the gasket sticking out and waving about, which made me suspect all along that it had been over-torqued:

 

finally, the front of the tranny was also wet.  that makes me nervous, as I wonder if the rear main seal might be leaking but we'll see once i change the oil pan gasket if it dries up..

 

so, over the next 10 days or so (I only work on her at night, once I put the kids and the wife to bed, and only a few nights a week, so nothing gets done fast), I'll be changing the gasket.   

 

from what I've seen, I can undo the engine mounts, jack up the engine a few inches, unbolt everything, slide the pan towards the back and put everything back the other way around.  I've seen it described, but have never seen it with photos.  I'll try to document everything with photos and hopefully not to many funny stories of how I screwed up....

 

Replies welcomed, even if it's only to say you're curious/interested!

Edited August 10, 2015 by supernova_6969

[Oddmanout84]

When I started work on my 280, I wanted to remove my oil pan for the stupidest reasons: to paint it orange. I told myself it was a good idea because I'd be able to see oil leaks better and because I was curious about what I'd find in the pan (there actually ended up being quite a bit of grit and half of a 3M sanding disc from god-knows-when). Back then I had no engine hoist, so I made do.

 

The short of it is that yes, you can remove it whilst installed. It will be an absolute pain though to get some of those bolts out. It was a tight fit, but I don't think I even had to remove the sway bar, or the engine mounts. Getting the thing back in carefully with gasket was a bit more challenging, but not impossible. Clean the surfaces well before you do, and it shouldn't leak. But at least when it's leaking, you know that it's not empty, right?

[supernova_6969]

Oddman, thanks for the comment.

 

I'm glad to see you managed it.  

 

the two problems you mentioned are the ones that bother me the most as well: getting all the bolts out (and then back in - arg) and sliding the pan back on without moving the gasket around.  I AM also thinking about getting the engine mounts back where they belong once i'm done, but one problem at a time (and that one I can strong arm into place.  not so with the gasket or bolts)

 

I was thinking of using a small bead of ATV sealant on the pan side, to compensate for possible issues with the pan not being 100% straight (i'll try to make it as straight as possible while it's out), which should definitely make my life more miserable as if the gasket + ATV moves around, it might create issues.   ah well, I'll live to tell you guys about that!

 

s

[Oddmanout84]

I used a very thin layer of RTV (the oil resistant type that looks about the same color as molybdenum disulfide grease and comes in a pressurized can) on both sides of the felpro gasket used, spread with my finger, and left to tack for about ~10-15 minutes before installing. Getting the bolts in is the worst, do as many of them as you can *lightly* with your fingers to prevent cross threading. It's cast iron, but it still happens alarmingly easy. For the tight ones you can't fit your hands in to turn, use a long socket extension and turn by hand. Don't use the wrench for anything but final torque, and even that's only 10-12lbs if I recall correctly.

[supernova_6969]

Hi again!

 

so I finally took some time for the 280, and the oil pan is out.  here is what I did.  I'm not super confident when doing this kind of stuff, so I took all the picts I would have liked to see before starting....

 

a few days ago, i undid everything that was going to be in the way : removed the fan shroud (turns out I only have the top half of the shroud;  I'll have to fabricate a bottom half.  that explains why it gets a little hot in summer traffic) and unplugged all the intercooler pipes.  

 

tonight, I took the pan off the engine. here is what I did 

 

first, i took apart the engine mounts.  instead of undoing it from under the cross member and leaving the mounts as a whole, I undid the bolts that are linking the part attached to the engine to rubber part (I hope that does not come to bite me in the ass by being super tough to re-position...).  I've taken shots of both sides from the front, but note that there are two bolts on each side, one in the front, one in the back of each mount, all easily accessible.  Here are photos with those bolts in the forefront.

 

once the engine essentially free from the car, I set up the jack under the trany and engine.  I don't have a hoist, so I raised the engine from under, using a floor jack..  I used two planks under the oil pan (the one close to the drain plug has a notch so that there is no pressure on the bump where the plug screws in), and one under the front of the trany;  I figured it was best to spread the load as much as possible.  between these and the jack is 2 2x4... 

 

I jacket up, and eventually, the car stopped raising, and the engine continued up.  the driver's side raised much more than the passenger side.   here is what I got on both sides. 

 

I stuck some wooden blocks in the space between the two halves of the engine mounts, although I first removed the top part of the bottom half of the mount (that's what I'm holding in the photo, under the oil pump, C-shaped... the part does not stand out, but you'll know when you see it).  That made it so that my pieces of wood fit.  I managed to put a 2x3 (thin side) on the driver's side, and a plank (about 3/4) on the drivers' side.

 

once that done, I ended up with a total of about 4-5 inches between the bottom of the pan and the crossmember/steering rack.  sorry for this photo, it's blurry.  gives an idea though;  looks like a cavern.)  even with that amount of room, I still had to fiddle a bit to get the pan to clear the bottom of the trany bellhousing;  I suspect getting that pan back on with the gasket on it might be a challenge.  I'll let you know, but I definitely suggest trying to jack the engine up a little bit more, maybe just enough to be able to put similar sized blocks of wood WITH the engine mounts that I took off in place... 

 

finally, I took off the parts that hold the engine and trany together (those bits cover the back part of the pan).  three bolts each, took 1 minute each with a 2 foot long pry bar.  this is the end result, where the engine meets the trany:

 

 

finally, i unscrewed all the pan screws. turns out that while I thought the leaking side had been over tightened, most of the bolts on that side were barely more than finger tight, while the dry side's were all snug.  looking at the pan later, I also realized that the holes on that side had at some point been over tightened and the lip around these is now bulging on the gasket side.  so two good reason for a leak (well, bad reasons, but....). the pan fell on the crossmember on it's own.  I tried to simply slide it back but it bumped against the very bottom of the trany.  i decided to give me a little bit more play by undoing the oil pick up ;  it's right there on the passenger side..  by the way, should I replace the gasket? can i use a paper gasket, cut of from gasket sheet?

 

once the oil pick up was out of the way, i still had a minor clearance issue (maybe 1/16), so I moved the pan back and forth and side to side a little (no need to push hard or anything) and it fell down.. 

here is the underside of the engine, and the pan itself, left to drain over night. 

 

so that's it.  tomorrow, I'm off to buy brake cleaner to use to clean all that (used the last of mine tonight).  I think i'll use either a little plastic brush or a kitchen scrubber to completely clean the bottom of the pan....  

 

as soon as I have time, hopefully this week, I plan on straightening the lip of the pan, cleaning the lip of the pan, cleaning the engine mating surface, then cleaning the pan and the engine again.  Then once more.   After that, a tiny ATV bead on the pan lip and a little more on the engine where the front cover AND the rear main seal meet the block, put the gasket on the pan, re-cleaning the engine, cleanly slide the pan back in (yeah right.  maybe on the 6th try), and screw all that up.  

 

that's it for now;  i'm going to bed, way too late.  comments welcomed.  seriously, just say hi if you like this;  it validates the trouble i'm giving myself.  

Edited August 18, 2015 by supernova_6969

[Team Zleep]

I actually have to do my oil pan gasket (and swap the pan out with a turbo pan... hehe) next week... So I'm all over your progress. I personally am going to use indian head gasket sealer when I do my gasket to keep it in place, and help it seal. As far as the oil pickup tube, I don't see why you couldn't use the paper gasket material and cut a new one, as long as you cut it cleanly and make sure nothing can break off and go for a swim. I could be wrong though, so maybe others will chime in. Personally, if it didnt break into bits when you removed it, I'd just re-install it and give it a very light bump in bolt torque. Not Hulk kind of torque, just an extra bump.

[supernova_6969]

Hey guys

 

Took a little time to work on the pan today. 

 

first thing to see is that the pan's lips have started to get pitted from rust on the outside edge (on the side that was dry, obviously;  the leaky side was good as new). first thing I did to the pan was to use a grinder with a brush wheel to get rid of most of the rust and whatever paint was on there.  I did that to the lip only, not the whole pan.  Here are two picks of the before..

 

As you can see, the problem that caused the leak is really obvious: the lip was raised around every bolt hole on the side that had leaked;  my final guess was that at some point they were overtorqued to the point where the pan's lips bulged around and that this had never gotten fixed.  The picture shows clearly every bump against pale background.  on the non-leaky areas, the lip of the pan is almost perfectly level. 

 

To get rid of that problem, I found something flat that fit under the edge of the pan (in this case a plank left over from a compost bin project), I lay the pan's lips on it and banged on the bumps until there were pretty flat.  It takes a surprising amount of force to bend those back straight (surprising is relative, I didn't use a sledgehammer, but it was more than I expected).  You have to be careful though, as I ended up making some spot a little too flat (the mating edge is a little raised all around the pan).  I had to lay the pan on a table and hit those spots with a flat punch from the outside of the pan (sorry no picts of that.  if you can't figure that out, go to the mechanics and get your pan changed there ).

 

Lying the pan flat on a table made me realise that the whole pan was slightly kinked, making the pan want to have a gap where it had leaked.  I'm not certain if I did that after hitting on it or if it was like that to begin with, but I fixed most of it by twisting it back into shape.  I didn't simply grab both ends and twist (tried, didn't work);  I had to put one side of the pan on a table with the other side far over the edge, and I put pressure where it kinked up (and on the table side too, duh). 2-3 times like that and it was better, but I ended up finding where it was kinked  (rocking it until I found the "high spot"), putting a plank right under there and pushing down on both opposite corners... that made it almost perfectly straight.  here it is before;  it's not super clear, but the pan really wanted to have a gap of about 3mm-1/8 of an inch...

 

After all of this was done I used a metal ruler (some sort of straight edge I have) to see if the lips of the pan were all level.

the first pict is how I used it, and the second is how it's supposed to look like when perfect.

 

Obviously, I have some spots that were pretty perfect and some that were weird.  The lip on one of the side of the pan was bent away for the block, making it so that the only spot that would have wanted to make contact was on very inside edge of the pan.  I used pliers to bend it back straight, being careful not to mar the mating surface.  I didn't get everything perfectly straight, but I figure I probably made a significant difference. 

 

I also used the ruler along the long side (just laying it on one side of the pan, as opposed to across like on the picture) to see if the mating edge was level and found a few more spots that I had to touch up with the hammer and punch;  eyeballing it earlier was good, but not good enough..  I managed to get everything to be flatish to within about slightly larger than a hair's width...  should be plenty good enough for the gaskets (I'll use a very thin coat of ATV gasket and a proper rubber gasket on top of that).

 

After all that was done, I cleaned the edges with the the wired brush again, then brake cleaner, masked the inside and painted the lip (and outside edge the lip, that was also rusted) with rust reformer paint.  I'm thinking it's probably no the best paint for the conditions it'll be in, but that's what I had so there you go.  I didn't paint the inside nor the outside.  too lazy, and I figured whatever was on there was good enough.   Here is the finished product.

 

Unless someone here tells me I did something wrong, the next step is to put it back on the engine.  I'll try to do that this week...  stay tuned, comments welcomed...  actually comments very encouraged. 

Edited August 27, 2015 by supernova_6969

[supernova_6969]

So i was thinking of a way to make certain the pan does not get all bumpy again....
I realised that on my pan, about half of the lip (back half on driver's side and rear of the pan) had these oil pan load spreaders, flat metal bars about half an inch wide, kindof like a flat washer that covers a few holes all at once, contouring the pan and going between the bolts and the pan itself. I didn't think anything of it at first but now i'm wondering if it's stock and if so, why is there only half of the pan covered...

this is one of the two pieces i'm talking about.  you can see it's not too straight, another proof of overtorquing...

Do you guys have that? If so does it go all around or does it cover only part of the pan like me?
I was thinking of fabricating some for the rest of the pan, to even out the pressure of the bolts.... Thoughts?

Edited August 26, 2015 by supernova_6969

[supernova_6969]

So I was about to put the pan back in the car when I talked to my dad.  never a good thing.  

 

I mentioned the work i'd done and asked that he thought of my plan to leave the pan's finish (painted some weird grey-brown colour) as is, even if there were a few very small bubbles in the paint.  he of course told me I shouldn't let it go, now that it was off the engine.   

 

So I did my research and this is what I did:

I first stripped the paint usinga grinder with a brush wheel.  I got it down to shiny metal (no photo, sorry).  Except that there were still some spots where the metal, while perfectly smooth, had a brownish tint to it.  To neutralize the rust (that just didn't go back to metal no matter how much I brushed it), I used a phosphoric acid-based product (rust check rust converter, bought at canadian tire)...  I followed the not too clear instructions and brushed it all over (with a regular toothbrush),  let it dry till it was all blackened and crusted,repeated, and did it a third time for good measure.  After that, I took the pan in my shower and rinsed it all up, brushing it with a toothbrush to get rid of the gunk that had dried on it. 

That was REALLY weird, giving a bath to unpainted metal, but I made certian I dried it right away, using towels and then a hair drier.  

here is what it looked like after this treatment..

It got all green with black spots, which I understand is normal and means the treatment worked.  I hope, anyways. 

That done, I primed it and painted it with a regular primer and some engine enamel paint.

I know red isn't the most typical colour and people say dirt and oil will show, but I wanted something that would pop a little instead of just being there.  We'll see how it looks in a few days when I put it in.

 

[supernova_6969]

hi!
the end is near!
yesterday, I painted the lip/contact area on the inside of the pan, as I thought the black mate anti rust paint might not be enough. forgot to take photos. but who cares.. it's simple enough. I also de-greased the bolts by soaking them in a container with WD-40 (I had it around) and giving them a good shake once in a while. I didn't paint them, which I wish I had, as they don't look as nice as the pan. ah well...

today, I cleaned the mating surface on the engine, found a little rust on the outside of that (the rust was basically just outside of where the pressure is put on the gasket: where the gasket sealed was perfect and next to it, very clearly delimited, was rust). I sanded that with 220, being careful not to sand the actual mating surface,. I didn't paint it or anything, I really just wanted to make certain the whole surface was flat.

Once that done, I covered the crossmember with a rag ( so the pan wouldn't rub and scratch), and did a practice run. I realized that I didn't have enough clearance to safely slide the pan in without having the gasket move around (I put a little RTV on the pan then the actual gasket, so it could't move around too much while I was installing it), so I re-jacked the engine and gained about 1/4 of an inch, which was all I needed. I also realized then that I could install the pan WITH the oil pickup in, so I made a new paper gasket (I had gasket material that was too thin, so I made two and stacked them) and put the pickup in the engine. The official torque for those bolts is 7-12 foot-pounds.


I then put a little tiny baby bead of RTV gasket all around the pan's mating surface. Litterally 1mm wide (about 1/32-1/16). I did that because the pan's mating surface is not 100% straight, so I figured the RTV would make up for that (sorry, forgot to snap a photo). On top of that, I put the actual gasket.

I'd previously made myself some studs out of an old bolt that was the same size as the oil pan bolts. I figured it might help me put the pan straight and hold it there while I was fishing around for my first 2-3 bolts..

I put a little RTV at the seams where the front cover meets the engine, and put one stud there.

and I did the same in the back..


Turns out the front stud was in the way with whatever little clearance I had, so I ended up removing it while sliding the pan in there (sticking my finger in the RTV sealant next to the stud as I was blindly fishing around, of course). The stud in the back helped out, tough, I definitely suggest doing that; the pan was not moving around as I was holding it with one hand and trying to screw in a bolt at the front.


So I put 3-4 bolts to hold it there, and them put the stock load spreaders that go around the pan between the bolts and the pan, then got the ones I'd made myself and put those ones on the remaining bolts holes (the ones that "came with the car" only covered about 1/2 the pan; the rest of that pan had the bolts straight on, and the pan was all wavy there from the pressure, so I made myself some extra ones so all the holes are now protected, and the pressure more evenly distributed).
So here she is, lightly torqued (about 1-2 ft pound). but looking good.




I'll let her rest that way overnight so the rtv cures, and tomorrow, I'm torquing them properly to their required 4.3-72 ft-pounds, and I'm resembling everything.

Edited September 5, 2015 by supernova_6969

[supernova_6969]

So it's done...

 

reassembly is the reverse of  disassembly, as they say in the books (or something like that).  I didn't have any significant issues with putting the engine mounts back in their place (which I kindof expected), just had to move the jack a little and they found their way.

 

The only thing i'd suggest is that, when you torque your bolts for the pan, give them a number.  physically. there is 31 one bolts and if you do like me, a criss-cross pattern, torquing them all to 25 inch pounds, then 50 inch pounds  and then finally to 60 inch pounds, you'll get lost.  what I did is I wrote numbers from 1 to 8 next to the bolts, which gave me 3 series of 8 and one of 7.  then all I had to do was to torque all 4 bolts #1, then #2, then #3 and so forth, and the criss-cross was perfect.  many people won't need to do that, but I usually loose my spot when I do stuff like that, so I would have lost a ton of time re-torquing the bolt next to the one I was supposed to torque and I didn't want to fool around....

 

Also when I torqued, I got them all to 60 inch pounds or so, and then I ended up going around 3 more times to re-torque them to 60, as the gasket compressed and settled...  

 

I haven't had a chance to see if it's perfect, as I realise I didn't have the right sized filter when I attempted to change that and put new oil (I bought three of the fu**ers, and obviously don't have the bill anymore).  That's a trip for Napa auto parts tomorow, who, unlike canadian tire, will give me the right model.  I suspect however that it'll do just fine.  the gasket is nice and straight, and so was the pan. I'l let you guys know if anything comes up. 

 

at this point in time, quite a few people have read the tread, at least one or two found it interesting...  I do hope this very basic, detailed guide helps some people who, like me, might not be super confident.  It's a bit long, but I figure it's best to have more info than less. 

 

Good luck, and please do comment when you swing by. 

Edited September 13, 2015 by supernova_6969

[Team Zleep]

Nice!

[supernova_6969]

So i drove the car aroundfor a few days and lo and behold, the car seems to loose oil about as much as it did before all this work. I checked it out and the gasket is still straight but it seems a little wet front passenger and the area read passenger is wet all over.

I checked the torque specs on the bolts amd they went from around 5ft-pound/60 inch-pound to about 3ft-pd/30in-pd. I cleaned it all up and retorqued everthing to about 6ft-pd/75 in-pd. To get the bolts to stay there i had to torque them all about 3 times and then some for ehere it leaked most. Hopefully that's the last i hear of them.

I'll let you know!

[supernova_6969]

so the pan is still leaking.  i'm guessing since the oil made it's way between the gasket and the block, there is no way to completely stop the flow....   unless something else is leaking (i'm looking at you rear main seal, although i'm not that accusatory).  

 

I have yet to go under there again to seen, but i'll do it soon....

 

next time i'm doign this, which is likely to be in a year when I rack enough mileage for a new oil change, i'm going 100% RTV..   we'll see how that goes.  

[supernova_6969]

quick question;  anyone ever re-used an oil pan gasket?

 

I'm not certain i'd risk it, but if other people have done it successfully....  

[Midri]

I've taken the pan off my engine twice, both times whilst still in the car. You've got about as much chance as winning the lottery as seating that gasket properly without taking the engine out of the car (or at least lifting it with a hoist) so you're going to get leaks and no, you probably should not reuse your gasket -- especially if you put the pan on with the engine still in the car, you probably ripped/stressed it some places.

Edited September 23, 2015 by Midri