code1

I've seen guys calling it a pre cat so I used the same terminology, but its listed as a catalytic converter online and was called that by the Nissan dealer I called. Eastern calls it a front catalytic converter if it is the cali emission converter located off the bank 2 manifold directly behind the radiator. I also called Eastern directly and talked to a tech because I was stumped regarding a gasket for the 5 bolt flange end. He said because of the lip on their unit, there is no need for a gasket...it seals itself. He also said some people have ground down the lip on the Nissan ring gasket down because they wanted to use it and to make it work, but there is a wire mesh filler in that gasket that is going to add height to the mating surfaces increasing the gap on the 5 bolt flange. The ring gasket is also a metal to metal connection, so its not like a fiber gasket so where is the benefit? Dimensionally, the machined inner face on the Eastern is about where the Nissan converter face is with the gasket installed. There is no way you can use the factory seal as is with the Eastern. I'm going to do as they say and install it as it. If I have leakage, I will pull it back off and add a high temp, hand cut gasket on the flange face. This will, however, move the lip that is supposed to block leakage further down and may just create another problem down the road.

code1

FYI, Installed the Eastern front cat without a gasket making sure all bolts were tight at the 5 bolt flange mating surface before tightening the 3 bolt flange bolts as per the Eastern tech. There is a slight variation at the 3 bolt flange mating surface that closes up once you tighten the bolts all the way. There aren't any leaks. Done deal!

Nelsito65

Thanks for the update.

denny_1986

iTrader: (1)

thanks for the update!
does the car sound any different? I still can't get over the fact that eastern cats dont require a gasket but i guess it is what it is!

code1

I was concerned too, but it runs smooth and sounds the same to me. I don't hear or feel any exhaust leak. FYI, I looked into replacement bolts for the flanges on both ends and they are available from Nissan for $4-$7 a piece which is rediculous. I was going to go searching in town at a fastener shop or online (McMaster-Carr), but decided to clean up the ones I had and re-use them.

Berto210

is it possible to use a high temp silicone gasket to be on the safe side, or just shup and do it???

code1

I would recommend looking up Eastern Mfg. online like I did or call the company. (800-553-7199) Ask for a service tech and explain the situation and decide for yourself. The tech told me they get calls all the time about this. I understand the concern...believe me.
The 5 bolt flange to the manifold both appear to be machined surfaces. If you feel the need for a gasket I would recommend going as thin as possible, I just don't know how silicone would hold up.

muravei2

iTrader: (2)

Would replacing one of the precats with a 49-state while the other precat is still cali-spec affect engine performance? I'm a little concerned about the cali-spec precat being more restrictive than a 49-state precat, so it would be like having two different headers. Any thoughts?

code1

In my case, all I did was replace the front cat with the 49 state. I feel like the car has a little more pep now than when it had the bad cat. So to answer your question, I don't see an issue. I replaced both 02 sensors on the manifold and the front cat at the same time because they were so accessible. I had already replaced the (02 sensor after cat) when this all started. I've driven a couple hundred miles over 4 days now and no CEL. I do want to replace the rest of the exhaust system since it looks tired as well...probably with the Eastern again, but that will have to wait for now.

Berto210

i saw some headers on ebay from a company called Race Design Imports. Anyone heard of this company or bought their headers package? The only reason why I ask is cause Im getting strapped for cash and thinking while im going to replace the front cat, i might as well do the headers too. Any feedback would be great...

Tee00Max

iTrader: (18)

yeah im gettin the P0420 constantly, it goes away and then comes back...i have aftermarket headers and my car is a fed spec....what should i do next? I thought about just getting an 02 sim.

denny_1986

iTrader: (1)

ok so what about the connection between the y-pipe and the eastern cat/? Did u install a gasket their?

crazyasian

if i changed the cat, would i get better gas mileage?

Davidpcvsamoa

I finished installing a Bosal precat and replacing the 2 uppermost 02 sensors with NTK universal sensors. It took two pry bars to get the original precat separated from the cat. With some finesse and force it came off. It tough to get separation from the flange but I guess thats what helps create the seal.

I did not install any gaskets. There appears to be a tight connection at both ends and the audio, visual and olfactory senses seem to support it.

Does Eastern Precat provide holes for you to screw the heatshield back on? The Bosal does not, so I no longer have a heat shield. I feel happy with the quality of the parts installed. No codes so far and the car feels like it has a little extra pep.

Thanks to everyone on this thread for their help!

Nelsito65

Thank you for the update. From what I've read, I don't think the Eastern cat has anyhting to mount the heat shield either.

Edward Lee

iTrader: (3)

I think that the only reason that the 49 state cat doesn't make it to Cali is testing costs for California.

My apologies for not getting hte SIT up yet. I have been terribly busy with work. Did the install, cleared the code and went throught the drive cycle. The car passed smog but barely. I am guessing that another cat is on it's way out soon.

Child_uv_KoRn

iTrader: (7)

Cats kill motors. Check out the POS ones on the altima. Who knows how many engines have blown up from that fiasco.

Same thing happened on my old max with a whopping 75k miles. Hollow the **** out or replace it all. It'll save you time, money and give more perf.

Maybe it's just a nissan thing for them to fail so early, but either way, I don't care. Cats are useless. What's the point of paying out a lot of money to fix a broken design. 20 dollar O2 sim and you're golden forever.

Berto210

where do you find those O2 sims??? Do you need to replace the front cat as well. I would think its possible that the front cat is causing my hesitation when in gear to accelerate (2nd or 3rd gear).

andrew629

I finally finished my Bosal precat install last week. As mentioned previously, I had one hell of a time getting it off of the front exhaust manifold . . . in the end, I said *#& it and removed the exhaust manifold and radiator to have some room to yank the hell out of the precat to get it off. The lack of a gasket confused me too, because I was the smart one that tightened the downstream (3 bolt) end before the upstream (3 bolt, 2 stud/nut) end. If you try to tighten the downstream end first, all you'll do is strip a bolt and hole (requiring a little tap/die action to fix) and nothing will line up right on the upstream end.

BY FAR: the easiest way to go about this, even though it sounds daunting, is to remove the radiator and front exhaust manifold before you do anything. It gives you a whole lot more room to work, you reduce how many times you scrape and cut your hands trying to get to hard-to-reach bolts, and you won't break anything. If I would have realized that from the get-go, my 6 day nightmare experience would have taken maybe 3 hours. Maybe. It's a good excuse to do a drain/fill on your radiator and coolant too, which is never a bad thing and takes way less time than you'd ever think.

My other strong suggestion: don't get pissed off at the stupid plastic under covers blocking your way to everything and rip them off. They're around $150 to replace from Nissan, and I haven't found them anywhere online.

Edward Lee

iTrader: (3)

^^^noob! It appears that you did it the hard way. There is absolutely no need to remove the radiator or the exhaust manifold.

I had mine off and the new one on in less than 30 minutes. That wasn't including placing the car on jack stands.

andrew629

With all due respect, I was a residential home AV wiring subcontractor for more than two years within which I put over 75,000 miles on my Max . . . many parts have proven to be quite a bit more difficult than others to replace due to that. There's quite a bit of sand, bumps, water, etc. involved in such endeavors, so by all means if you think you can do it better/faster/stronger, you're more than welcome to lend a hand next time.

denny_1986

iTrader: (1)

just got off the phone with Will at Eastern Catalytic. He said that they are still in the process of engineering the gasket for the upper flange but they have been selling the unit for years and people generally don't have any issues with it....(i highly doubt a new gasket is in the works )....this is in regards to the pre-cat model # 40387

A gasket does come for the lower flange with the new pre-cat...

I should be getting in the cat either today or tomorrow....will have it installed this weekend and report back on the results

I paid $211 for the new cat + 2 front rotors and free shipping. Not bad!

Nelsito65

$211 for all 3 items? That's not bad at all. Where did you get that deal? (if you don't mind sharing)

denny_1986

iTrader: (1)

i got the stuff from

http://www.wundercarparts.com/


they also have an ebay account..

i haven't seen the stuff yet so cant vouch for them but i will say the shipping is super fast!
Ordered the stuff yesterday and one package is on its way to be delivered today and the other one tomorrow!

Amave

all this talk about cats, mine has a test pipe where the 3 way catalyst goes, but i'm am not getting a dtc for a missing cat. only dtc in the ecu is p1336 crank pos sensor and nothing else.

it still has the oxygen sensor after the cat/test pipe

denny_1986

iTrader: (1)

just got the eastern cat installed.
didn't drive the car around much after the install but so far the car sounds and feels the same.....

If anyone cares, a closeup of the eastern cat...

hi-tek22

iTrader: (4)

^^since you recently did this...I have yet to purchase my Eastern cat for my p0430, I was wondering if you managed to get the heat-shield back on, or do they not have support brackets for the heat-shield?

Oldnewbie

Edward... Strongly suggest that you (and other SoCal drivers here) check all my posts on the thread at

http://forums.maxima.org/5th-generat...rong-fuel.html

As you later state that you are in SoCal (as I am), the new laws and their enforcement will apply to you and other 5th Gen Max drivers with cars registered in Cali.

I'll not claim that everyone's problems are the same as mine (re cats and sensors on my stock '01 SE 5-Speed), but the legal hassles are the same for all Cali registered owners.

As for the "standard" Nissan manual procedure for isolating pre-cat vs. cat vs. sensor problems mentioned by others here, consider the source. The manual was written by Nissan for Nissan first and, only after that, for the end-user/owner. (Witness, my experience with their initial $2.3K repair estimate for all cats and all sensors, based on a single DTC code with their follow-up in-shop analysis, and the actual cost (in their shop) of $500 to fix the real problem - but only when I insisted on the order of repair. They follow "their book" and I follow mine.)

I don't mean to second-guess those with more experience here, but only to highlight the problems for Cali drivers - leaving (most) comments about Cali politics to the political blogs.

00NisMaxSE

I also had the P0430 code and bought an eastern cat. thanks for answering my upper gasket question but while i was removing the bad cat i broke the 3 studs off the front and i know that andrew629 said he removed his manifold but i don't wanna break the freaking manifold studs. So does anyone know a way to get the broke bolts out? i can't get a torch in there bc the to much to **** up. HELP!!!

richb500

I just installed this cat on my 2000 Maxima and I do have an exhaust leak at the top. It's minor, but I smell exhaust coming out of the cat. It might be the lack of gasket, or it might be that I couldn't tighten one of the bolts to spec.
I had problems getting one of the bolts out - (it was really tight all the way out). I'm not sure if someone had messed up the treads putting it in or what. I bought a new bolt just to be safe ($5 - gotta love dealer prices). The new bolt went in fine, but when I was tightening it felt like it was starting to strip, so I couldn't torq it to spec. It is tight, however. I can't believe that the fit is so touchy that this would cause a leak. I'm going to replace the bolt with a longer one so I can put a nut on top of it just to see if this solves the leak.

Does anyone know the specs for this bolt - so I can buy one about an inch longer?

Thanks,
Rich

richb500

OK, so I got brave and went back and tightened the bolt to spec (it turned out that it was actually almost there). I checked all 5 and they are all tight. The leak is still there. In fact when I start the engine, a little water even comes out of it. When I put it on I tighted the bolts in a cross order like you do a wheel to make sure it centered correctly.
I really think this connection needs a gasket and anyone who has been sucessful has either gotten lucky or have a minor leak and don't know. Perhaps my manifold is slightly warped or something and this gasketless connection is so precise that it won't seal.

I'll call Eastern Monday when they are open and see if they have any suggestions. Anyone else have any suggestions?

richb500

Yeah, if people generally don't have an issue, why would they engineer a gasket for it. I suspect Nissan must have a patent on the design. I can't understand why else they wouldn't just build it the same way as OEM.

Eastern told me a different story. They admitted that many people have problems with it leaking and have various solutions... sealer, muffer cement, homemade gaskets, etc. Then, he "looked it up" and found that they said that I could just use the factory gasket. They said in 2008 they redesigned the cat so it can take the factory gasket. It doesn't. First the ridge on the Eastern is slightly smaller in diameter so the gasket doesn't fit in. Second there is a ledge inside of the ridge on the Eastern. The factory cat has a slot around the inside of the ridge which allows the gasket to drop dop.

I requested a refund from where I bought it ( www.wundercarparts.com ). Hopefully they understand and don't give me a hard time.

Nelsito65

Interesting observations. I wonder if the Bosal precat, or other manufacturers for that matter, have the same issue with the lack of accommodation for a gasket. I do believe that something has to be placed between those two surfaces to provide a tight seal, no matter how smooth their surfaces are. If worse come to worst when I replace mine, I'll place at least a small bead of high temperature liquid gasket.

richb500

Well here's the problem.... Nissan designed the connection to seal using a metal ring gasket that makes contact with a ridge INSIDE of the exhaust manifold. They don't rely on the flange around the outside of the pipe to make the seal... thus they have no gasket there. The Eastern cat makes no accomodation for the gasket inside of the exhaust manifold and rely on a leak proof connection on the flange where the two surfaces meet OUTSIDE of the exhaust manifold where the bolts are. This is the obvious place to seal the connection and seems like a simple gasket here would work fine, but for some reason Nissan didn't go with this option. Instead they devised a metal ring gasket containing a wire mesh to push up inside. Perhaps they had issues sealing on the flange or thought they might over time if the surfaces warped. It's interesting.

The other thing I just can't understand is why Eastern doesn't offer a gasket that goes on their flange. It seems like it would probably work fine. They do provide a gasket for the other end.

Part of me wants to just go with a liquid sealer or try to find/make a metal gasket that would work and call it a day. I just want to end this project and get the car back on the road! The problem is I hate the thought of putting it on and having to take it off again.

cpygmyman

So is it a correct assumption that the eastman #40387 is the easiest way to resolve the PO430 problem? Was anyone able to find out a difinitive answer to the gasket issue. One this has been installed theSEL just goes away? Thnka for everyone's help!

catalogmanager@easterncat

Hi Guys my names Will. I'm the catalog manager @ Eastern Catalytic referenced in an earlier post. Just stopped by to clarify the confusion regarding our # 40387.

WE HAVE REDESIGNED THE FRONT FLANGE TO ACCEPT THE OE GASKETS

Neither of the gaskets (mesh/sleeve) are included with our converter.

As they do not crush or deform when installed it is recommended one reuse his/her old gaskets or purchase new ones from a dealership.

Our original design was engineered with the wider lip to negate the use of the gaskets. The majority of customers had no problems with leaks using this design without the gaskets. Never the less we decided to redesign the front flange.

The picture below should clarify;



Hope it helps

richb500

Hi Will. Thank you for joining this thread. It shows that your company is interested in satisfying it's customers. A lot of companies today don't go that extra mile. I don't want to mislead anyone away from your company, so if I'm wrong I welcome your clearification.
I did receive your New designed cat. I can see in the picture that your New design looks like the inner diameter of the ridge is larger - and I agree that it does allow the gasket to go inside the ridge.... the problem is that it doesn't allow the gasket to go on deep enough to use it. The gasket is about 3/4 inch high and is made to drop inside the ridge. The outer edge of the gasket is made to fit in between the outer wall of the cat and the "grid" center of the cat. The inner edge of the gasket is shorter and has a wire mesh inner gasket extending out if it. The wire mesh portion of the gasket rests on the inner surfice "grid" of the cat. The ledge that is inside your ridge is not on the oem cat. Your ledge is located right where the gasket is supposed to be inserted. The gasket goes on barely 1/4 inch and comes to rest on the ledge. This makes it stick out too far to use. When you try to install the cat, the metal gasket makes contact with the ledge inside of the exhaust manifold with about a 1/2 inch gap still between the flange and the manifold. I suppose you may be able to torque it down enough to crush the gasket.... but this isn't the way it is supposed to work. As you said, the gasket isn't supposed to get crushed.

I have pics if you want me to post them.

Out of curiousity, why didn't you just design your flange to be identical to Nissan's, since you sell it as an oem direct fit replacement - especially after you found your first design was inadequate?

catalogmanager@easterncat

So heres the verdict. The original cap used by Nissan had 4 feet or little protrusions around the edge. The replacements now being sold by Nissan do not have them and fit our redesigned #40387 perfectly.

IF REUSING YOUR ORIGINAL GASKETS ONE WILL NEED TO GRIND OFF THE FOUR FEET IN ORDER FOR THE CAP TO WORK WITH OUR CAT.

Original used by Nissan;




What they sell now that will fit our redesign;







We're going to put an instruction sheet in the box with these soon explaining and picturing the OE one with the feet to grind off.

Rich, I'd love to see the pictures you have too, either here on the forum or to wcole@easterncatalytic.com.

Thanks again guys!

dortega21

I just bought a 2000 max se with 170k for cheap. The car had the ses light on when I bought it. The next day after I took it to autozone and it came back with a p0430 code. After much reading and many estimates I realize that it was an expensive fix. 3 days of owning the car I have used nothing but premium gas. On the 4 day the ses light code has gone away. Can gas be a reason?

richb500

Will,
Bingo! That must be what my problem was. It was weird - you insisting the gasket fit and my knowing it doesn't. I'm glad you figured it out for us.

My car has the older cap - taller and with feet. It looks like the other cap would work perfectly with your cat. I do believe to make the old one work I would have to grind off a little more than just the feet. I think the whole outer wall is also a little taller on the old style. I recommend going to Nissan and buying a new cap. It's around $12.

As a heads up - Nissan is still selling the old style too. Orignially I went to Nissan to see the factory cat and gasket ($800). I looked at the gasket in the box - and it was the old style with the feet. Later when I decided to go after market I bought a new gasket - again old style with the feet. I'm sure it depends on your VIN and mfg date. Mine was mfg 9/09 and must call for the old style. By the looks of it, the new style would fit fine on mine. I would just have to get the part number.

My friend, a former certified Nissan mechanic, said not to reuse the inner mesh gasket. Always replace it (around $12 too). Comparing the old one to the new one I agree that the wire mesh gets crushed and corroded.

So my advice to people... buy an Eastern Cat from wundercarparts.com. Buy the new style cap from Nissan if yours has the feet and buy a new wire mesh from Nissan. The whole thing will cost you around $200 total.

Eastern putting the instruction sheet in the box is a great idea. If possible, I would also include the Nissan part number of the new style cap in case people would rather buy a new cap.

Thanks again Will.

-Rich