Do I need to use these brackets when installing the oil pan?

[Guest bastaad525]

This is on an '81 turbo motor, I don't know if other Z motors have these or not.

 

Anyways, my oil pan has these two brackets, one of them L shaped, the other one just a straight section, that are between the the bolts and the oil pan itself. They don't cover EVERY bolt, maybe about 3/4 of them (the rear and sides of the engine), with the remainder just going directly against the pan.

 

Anyways, I'm starting to wonder if these brackets may have something to do with my constantly recurring oil pan leaks. I've already checked the pan itself for straightness and it was fine... I never thought to check the brackets though. Maybe one or both of them are slightly warped and that is causing me to get false torque readings when tightening the pan bolts, thus not tightening it enough and causing leaks?

 

I'm going to hopefully be replacing the gasket YET AGAIN this week... I'll check the brackets at that point... but I'm just wondering, do I even need to use them? Does everyone else on here with an L6 motor use these brackets? What is their purpose and what will happen if I just leave them off and put the bolts directly to the oil pan?

 

 

Also, is there a special order you're supposed to torque the oil pan bolts in? I don't see any mention of this in the Haynes manual.....

[Here comes trouble]

Those brackets are even on the L20 B 4 cylinder. I would use the tightening sequence of the head bolts or the main caps of the crank dispalyed in repair manuals and start in the middle.... 1978 Z Service manual : 4.3 to 7.2 foot pounds or 0.6-to1.0 kg-m............... I use the old school non hardening black crap gasket sealer and eyeball the gasket as I tighten not using a torque wrench but my wrist discomfort with my hand gripping the 3/8 ratchet head... You don't want that oil pan gasket compressed very much.....the brackets if not warped should act as more support to seal the pan against the engine... Harbour Freight has little 1/4 inch click stop torque wrenchs in inch pounds...

[Guest bastaad525]

I'm not going to use any sealer this time. Out of 5 times I've replaced the gasket the ONLY time it DIDN'T seem to leak was when I just used the gasket by itself. Then I found out my thrust bearing was bad so had to pull the pan to replace my main bearings... used some sealer on the gasket and now it's leaking again.

 

I'm gonna buy a Felpro gasket... I've used Felpro gaskets many times on my valve cover and NEVER use any silicone or anything like that and have never had a problem with them leaking even once... so I'm guessing the oil pan gasket should be the same if it's made out of the same material... it LOOKS like the same black rubber material.

 

The shop I've been having do all my heavy work on the Z also advised me to just use the gasket straight with no silicone, or possibly to use copper spray on the gasket at most.

 

Another question, why is it so important to torque the pan gasket only very little? I know if you WAY overtighten it it tends to cause the gasket to squeeze out and cause a leak... the problem is if I only tighten them to 7psi they seem to keep coming loose. Should I use loctite on them???

[akeizm]

My friend and I didnt put the brackets back on and the sumps havn't dripped once. I believe 1 of them is used to drop the exhaust from hitting the point where the block and sump meet (well that area has a bracket that sticks out, only reason I can see it being there).

[Guest bastaad525]

akeizm - ??? are we talking about the same brackets? Not sure what you are talking about as far as 'dropping the exhaust'. The brackets I'm talking about aren't really 'brackets' at all... I didn't really know what else to call them. I guess they are like... washers? I dunno... they are just two flat strips of metal that are inbetween the oil pan and the bolts that hold the pan to the block.

 

 

So has anyone NOT used these brackets?

[akeizm]

yea 2 right angle L brackets. Thin pieces of metal about 2mm thick. Has about 10 bolts go through them.

[Guest bastaad525]

yeah well one's an L shape, the other is just a straight piece on mine... yeah roughly 10 bolts thru each of them.

 

So if I don't use them I wont damage/dimple the oil pan?

[S15 200sx owner]

They will be there to help even out/ spread the clamping force of the little bolts, why dont you just use them?

[akeizm]

If it was to help spread why not have a couple of brackets so it would cover all parts of the sump. I dont see how having it in 2 corners, or only in 2 spots will seal the sump better than an even pressure all around with no brackets.

 

But yea mine prolly had that little shield on the brackets cause someone built some headers that went close to the sump....top job that was lol.

[slownrusty]

Yup they spead out the clamping force - distribute the torque of the bolts and not point load against the oil pan lip. The oil pan is a very soft metal as it is so uneven distribution of torque from tightening up the million bolts that hold the oil pan to the block will eventually end up with leaks if you do not use those L-brackets.

 

Tempting to eliminate, but please don't

 

Yasin

[Sean73]

I've also had recurring oil leaks at the pan, and I am convinced it's not the gasket but the pan itself. oil pans tend to get warped and bent around bolt holes, so the gasket doesn't seal flat.

 

have you tried the competition oil pan gasket from MSA? the thicker gasket may help smear out imperfections in the pan.

[Here comes trouble]

Fel Pro gasket maybe the solution.. I priced a Nissan head gasket for an L20 B.......$69.00 ........... straight edge the pan and brackets...............

[datsunlover]

I didn't put them back on my engine, and haven't had a leak yet.. I've only had her out for a month or so, but I drive it really hard and it's been hot lately too.. I DO have a slight leak from the front end, but it's from the oil seal behind the fromt pully/balancer.. er.. well, the seal's good but the balancer had a chip which I 'fixed' with JB weld, so guess where the oil is coming from.. I figure by the time the pan starts leaking again, I'll be pulling the motor anyway to either turbo it, or go V8 so I'm not woried.

[Cody 82 ZXT]

Yup they spead out the clamping force - distribute the torque of the bolts and not point load against the oil pan lip. The oil pan is a very soft metal as it is so uneven distribution of torque from tightening up the million bolts that hold the oil pan to the block will eventually end up with leaks if you do not use those L-brackets.

 

Tempting to eliminate' date=' but please don't

 

Yasin[/quote']

 

 

Personally, I think this is the answer that is needed. If your bolts are coming loose then use some light loctite. I think it's the purple that has the least holding power.

 

Also, look at the bottom of the block so make sure it doesn't have any nicks etc...

[Guest bastaad525]

thanks for all the tips guys.

 

well again I'll be checking the brackets this time to be sure they are straight... I dunno why but it just seemed to me they might have been the cause of the problem, as I said I did check the pan and it was not warped at all.

 

I do still think the brackets may be partially responsible for the bolts loosening, but I'll use some loctite this time so I hopefully don't have to worry about it.

 

when I last replaced the gasket, I checked the block surface and it looked great all the way around. If it was damaged at all, what are my options then???

 

I'll be using the fel pro pan gasket again, and as I said, no silicone or anything like that, or MAYBE I'll use copper spray if you guys think this is a good idea?

[slownrusty]

To be honest I find I have had the most success with Permatex UltraGrey instead of using a gasket...I love that stuff, when I die, my wish is to have a tube of that resting next to me.

 

Yasin

[Cody 82 ZXT]

when I last replaced the gasket, I checked the block surface and it looked great all the way around. If it was damaged at all, what are my options then???

 

Honestly I'm not real sure other than using some extra sealer or something like that. I think it would be hard to damage the bottom of the block but, I guess it could happen.

 

I'll be using the fel pro pan gasket again' date=' and as I said, no silicone or anything like that, or MAYBE I'll use copper spray if you guys think this is a good idea?[/quote']

 

I like the copper spray on lots of things. Real easy to use and not messy if your careful with it. Personally in this situation I think I would go ahead and use something with the gasket like the Permatex Grey or the black RTV.

[Guest bastaad525]

LOL come on guys I only want to have to do this once (or rather... once more!). For whatever reason, I've had bad luck every time I've used silicone. I think maybe because I always have a hard time applying it in a nice even bead... or applying the right amount maybe? I dunno. But again, the one time I DIDN'T use silicone, was the one time I didn't have any leaks. And again, when I use the felpro valve cover gaskets, I never use any silicone, and have never had a leak. As a matter of fact, come to think of it, I know the valve cover gaskets come with instructions saying specifically to NOT use any silicone with it. Though, I can't remember seeing a similiar note with the pan gasket. I'll have to check for that this time. I do know they feel like they are made out of the same material... black rubbery stuff. But the valve cover gasket is metal with the rubber sandwhiched around it... whatever difference that makes (other than making it MUCH easier to install than a cork gasket).

 

I guess that's a negative on using copper spray though since no one seems to have vouched for that.

[technicalninja]

Copper spray will work great, It needs to be applied to both sides of the gasket in 3-4 light coats with 10 min between coats and the final coat 5 min before assembly.

The grey stuff is great as well. It requires no gasket at all. The first place I ever saw the grey RTV used was on Toyota R series oil pans. On a factory seal you had to physically rip, hammer, pry, cuss, pry some more, get a bigger screw driver, and finally get the pan to break loose; 30 min after you had gotten the pan bolts off. Sort of a mess to clean up to as no debris can be left on surface as it can effect the next application. I actually bought it from the Toyota dealer at $15 a tube for years before it was available through the aftermarket. I have used the stuff on the widest variety of applications. I have never had a failure when using the grey RTV.

I have never used it on a Z oil pan but have wondered how well it would work.

The probem I have is that the Z oil pan has a raised rib down the center of the flange where a pan designed for RTV has depression at this same spot. The Z design applies pressure to "squeeze" the gasket where the RTV style allows a thicker section of RTV at the center to improve seal. When tightened, the Z pan will squeeze out most of the RTV leaving a fairly thin center sealing section. I bet it would work just fine even with this design. I may try this on the next Z motor I build. Sure is cheaper.

Iv'e put Z pans on with Gorilla snot(weatherstrip adhesive), Pukkey (Permatex Aviation-Forma-Gasket), Copper coat spray, grease, and dry.

All chemicals formed working seals and althought each has its drawbacks what you use is probably not your problem.

Every Z pan that I have had off has needed each bolt hole lowered from the pan sealing surface. Years of use, and sometimes overtightening "dish" the bolt holes toward the block and this creates lower pressure sections between bolts in pan clamping force on gasket.

The fix is to place pan between you and a strong work bench pinching it to the bench with your body allowing only the flange on the opposite side to hang on bench.This can mark up the "work bench" so make sure your wife won't care about what your hammering on. Place a small ball-peen hammer round knob down in a bolt hole. Strike it lightly on its front face with a larger hammer effectively re-bending the hole back to flat and maybe a little the other way. Taping a small peice of wood, carpet, etc on the face of the small hammer will keep the hammers from chipping each other; never actually scene it happen but it can and it would throw very small sharp peices if it did. Use safety goggles when doing this trick. After a couple of holes you will get the feel of how hard to hit each one and I can rebend all 31 holes in just a few min.

Make sure the pan is fairly flat by placing it on a finished hard floor and checking clearances. You can take warpage out by shimming the high spots with thin plywood, masonite, extra floor tiles and using your body weight carefully "stepping" the warpage out. You can get one pretty flat with a little work.

The flange stiffeners need to be used as they add strength. Obviously the areas of the pan around the sump required Nissan to design a fix. Big companies don't usually make an update to a design unless it is cheaper than their expected warrenty claims (safetey stuff not included). If Nissan was worried enough in a 36 month warrenty period to add these I'd keep them.

They are usually warped up at the ends (the center of each leg hits pan first).

Unless they appear damaged I leave them alone as I think the bend is intentional on Nissan's part.

There are 16 long pan bolts and 15 short ones, long go with brackets.

Five "blind" holes in block, 4 in front cover, 2 in main bearing cap require a correct length fastener and verification of no trash in holes. Other 20 are pass throughs and are less critical on bolt length.

What ever you use the pan surface and the block flange need to be really clean and not have any oil on it. least effected by oil is grease and most effected is RTV. The RTV works very best when the surfaces are spotless ( I use alcohol and paper towels for final cleaning if possible).

Doing it in the car makes it very difficult to get it properly clean.

All the sealants work best if the pan is placed only one time and is held against block by helper while you lightly tighten 4 bolts and semi-lock the pan in place. I tighten from center of motor (sides) out towards ends with the first round just barely compressing gasket. I will bring up torque in three rounds then let the gasket "relax" for a couple of hours and recheck one last time. At proper torque the cork rubber (stock style and thickness) will appear slightley swelled where it come out from under pan and there will be slight (1/16-1/8") protrusions at each bolt. This works fine with all glue type adhesives but can't go this tight if you grease gasket.

I don't use RTV if I have a gasket for the joint. RTV replaces the gasket.

 

My suggestion: Try RTV if you can get the mounting faces totally clean and dry. If that is unlikely then either the Copper-Coat spray or the pukkey. The pukky is more forgiving for assemble as the CopperCoat is hard to apply evenly to both sides of gasket and it sticks to every thing it gets close to during assembly.

 

Thought my ramblings might help

Rick

[Guest bastaad525]

Hey Rick

 

Thanks for the very deep reply... well you've kinda cleared up the dilemma for me... only wish I'd read this post BEFORE heading to auto zone to pick up the stuff.

 

After all of the earlier replies in this thread, and then also talking to another friend of mine who's been working on Z's for a LONG time... I actually did decide to go ahead and go with silicone, and picked up the RTV Ultra Blue, which claims "Outstanding oil resistance!". That line kind of sold me on the stuff

 

But, reading the directions on the back of the packaging... it does seem to indicate that this stuff is supposed to work on it's own, with no actual gasket involved. And the directions also say as you do, about it being absolutely imperative that the surfaces be 100% bone dry and clean for this stuff to work... this might be the cause of my problem right there. Doing this job from underneath the car... it is VERY hard to keep the block surface clean as left-over oil is constantly dribbling down. It always dribbles down at the rear passenger driver side of the engine (or passenger side... I forget, which ever side sits a little lower), big coincidence... that's also always where I get a leak!!! So I'm kinda hoping that is why this keeps happening.

 

I have seen the grey stuff, actually a nissan service tech told me that's the stuff they use on everything now, but he agreed with you, the problem is the L28 pan is NOT designed for this type of silicone... the raised ridge will most likely squeeze it out. All newer cars have that depression you mentioned along the mating surface of the pan where the silicone is applied. He said on older Z's they ALWAYS use an actual gasket, and use it dry (which sort of surprised me). That's with the Nissan gasket though, he wasn't sure if a Fel Pro (which seems to be made out of some kind of card board???) would work this way, and recommended against that as well.

 

So after reading your final recommendation, I think it's back to plan A, which is the Felpro gasket with Copper Spray. I think the RTV ultra blue is just too risky since it is really hard to keep the block surface clean. I'm assuming then, with the copper spray, that spotless clean is NOT absolutely imperative for a proper seal? Or do I still need to obsess every time a drop of oil dribbles down?

 

Well, I'll be doing this early tommorow morning. Wish me luck guys I really, REALLY do not want to friggin do this again and I"m so sick of this thing leaking!!!!