Timing Guides and Plenum Work

[desertq45]

As a newbie on this forum (see driving moms car status) and only finding it a day ago thanks to msscomm (thanks again Mike), I can only say that this is the most impressive resource that I have found for any car I've owned.

By way of introduction, I am the original owner of a 1990 Q45 w/127,000 miles and have seen the issues most early Q owners have experienced even though I "thought" I was properly maintaining the car and promptly fixed anything that went wrong.

However, upon finding and reading the timing chain guide posts I sat up and took notice that perhaps there were some things lying in wait to bite me HARD later. So now I'm in the hunt for an Arizona shop that I can trust to do this. Thanks to AZhitman (Greg), Mike and Fred I am starting to work that out I think.

Incidently, I found the Yahoo group first while looking for info on the tension rods and and under plenum hose replacement and that is where Mike entered and sent me here. I found the plenum hose kit at Infiniti of Scottsdale's site and thought it was a standard OEM kit. So I called Pinnacle Infiniti (actually a lot closer to where I live) and they didn't have any kit or know of it. I could get all the hoses individually, but not together. They were really friendly, and admitted that the kit was a darn good idea but said I probably ought to call Joe.

So that is on it's way and I get to experience the joys of plenum work in a few days. While I'm at it I figured I'd replace the fuel pump (still original) and of course the tension rod bushings. Once complete, I will decide where to go and make an appointment for the guides.

That along with previously replacing the plugs, injectors, a/c et. al, water pump, upper links, struts (tokico blues), transmission, drive shaft, front main seal, valve covers, and misc. things like sun roof motor and 3 window regulators (great design there... that plastic really loves the Arizona heat-- bought the first fixed the second and third myself), and the sun visors (fixed them too-- simple fix) should round up most of the usual suspects... I think??

Anyway, just wanted to say kudos to all who have posted both in the past and recently and thanks in advance for the help (I'm sure I'll be asking as I tackle the work still ahead).

[elwesso]

Have you seen my writeup..... http://infiniti.home.insightbb.com

Click the only link on the page....

Im going to add the parts list tonight, which was more than enough......

[desertq45]

Wes-- yes I read it twice. Great job! Really helpful as a foreshadowing of things to come. The parts list will be a big help as well. I would really like to fix anything necessary while I have it apart and prevent a 30 mile (one way) drive to get parts. I really don't know how comprehensive this hose kit from Infiniti of Scottsdale is, but from the diagram it looks pretty complete.

QUESTION: This may have been answered and I just missed it (I've read a lot of posts over the last two days) but is it necessary to change the runner gaskets where they connect to the lower intake? I was told by a friend that they are about $20/ea. and you need 8 of them...

Also I spoke with "firstq" today regarding a shop he uses here in Phx and then called the shop. Turns out the guy (Scott) is really familiar with NICO and Infinitis... told me he was trained as an Infiniti tech and had a couple other Infiniti techs working for him now. Said he does ALOT of them and the Q timing chain guide job would run $800 plus parts (which he said I could order from Scottsdale myself since NICO members get the same or better discount then he does??). Sounds like he is in the ballpark so I'm going to visit the shop and have a look (it is called Euro Imports2650 N Scottsdale Rd, TEMPE, AZ 85281 - 1070 (480) 990-0193). Based on the feedback from "firstq" it appears to be a good alternative to the dealer pricing.

ANOTHER QUESTION: I've read a couple of posts, especially from Greg that discuss the merits of OEM filters... and Mobil 1 oil. I have been running Mobil 1 for close to 10 years, but not sure I understand the filter logic... also it seems that the OEM's that are coveted are hard to find now? Something about a design change? So what is recommended here? (OK so this is more than one question).

Thanks.

[desertq45]

In regards to the timing chain guides--

Since the thing is going to be opened up (and I know I read this somewhere too) what is considered "mandatory" and what is considered a "good idea" to replace?

I remember that there was discussion about the timing chains themselves and concensus was that they would go 300k miles np. However the "kit" from Scottsdale contains them???

Also, I remember a number of recommendations for Oil pump and chain?

I just want to make sure I don't miss something when I spell it out to "whichever" shop I have do the work... I'd rather be too specific than have it skipped because I didn't request it.

Thanks again.

[elwesso]

As Q45tech has said it doesnt matter what kind of filter you use as long as you change them every 90 days!!! Mobil 1 filters are fine... Anything but fram, supertech walmart brands are good too!!

You want to use my parts list. The scottsdale hose kit only includes 1/3 of the hoses required (mainly just the PCV hoses and air hoses).... You will need the big ticket ones (2ndary air system) and the coolant hoses (very important)... BE SURE TO GET THE BULK HOSE I LISTED ON THERE....

According to the FSM, you do NOT need to get new rubber plenum donuts, but its not a bad idea... $20 for a set of 8... Still a very good idea to replace them...

The lower ones, i didnt remove the runners, as you gotta remove the fuel rail for that (I wasnt diggin that!!)... Clean them out really good with carb cleaner (spray then wipe) until very clean... Change the oil after...

No reason to remove the runners... It would make some things easier.. Its your call, take in mind that a few hoses CAN NOT be reached without taking off the runners.... I wouldnt see why the metal gaskets couldnt be reused... I would get them and if you dont use them Joe is really good about returns.....

[desertq45]

You're the latest in a long list of people to "warn" me about Pinnacle's service dept. and I'll heed your advise there. I have bought parts from them simply because the price was the same as Scottsdales and they are 5 minutes from my office-- 20 from my house. But I wouldn't dream of trusting them with my Q.

I have heard good things about a couple of guys at Midway, and have had one minor repairs done by Scottsdale but you are dead on about the price. Quote from Scottsdale for chain guides was over $2500.

[AZhitman]

Good stuff.

Brett, it was a pleasure talking with you today. Let's try to catch up for lunch one day and we can talk cars more - I'm downtown (across from the Capitol).

Keep us posted on your car.

[desertq45]

Ditto Greg-- I really appreciate your time and insight along with the intro to Arshad, he was a lot of help too.

I'd like to hook up for lunch and talk cars. Maybe we can meet half way or something... I'm on Evans between Hayden and the 101.

I'll let you know how things progress.

[AZhitman]

What part of town are you in?

We're getting quite a core group of NICO members (finally) in Phoenix!

[PalmerWMD]

First 18 months of production have slightly different heads which were changed for more relaibility in mid 91 my production.Original design may have been reason for the rumored better power of the earliest engines.Little is known for sure here and changes are all pretty small.

92 was last year of sodium filled exhaust valves.A 90 or a (early?) 91 would be strongest according to lore.92's are also very strong.93's ecu was abit less agressive due to dropping sodium filled exhaust valves.94/94 a bit better midrange a bit less peak power.96 no VVT.

Fred...

[AZhitman]

96 also add OBDII.

[maxnix]

Is it just lore? Couldn't q45tech or someone who has worked on countless year/engine Q's confirm this?

It's all in his previous posts - required reading for anyone wanting to know all about the G50.

[PalmerWMD]

The info on the head design is from Speedoctor (site founder) as well as Charles Wright owner of T3, in personal converstaions.

Dennis has also written, that the first year and a half seem stronger over the years as well, but a year ago he has expressed some skeptiscm to me in a personal converstion, if that is really as significant as is often believed by the congnoscenti.

Fred..

[Q45tech]

In the post 93 engine the designers may have given up peak air flow [into cyliners] for better balance and to correct some emission problems.Same with the progression to 93 a tweek here and there to address customer compliants [ like the 91 transmission debacle].

10 HP difference is at most 0.1 out of 15.1, so it will be unnoticable in zero/60 or 50-80.

When the engine's air passages are internally clean and the injectors flow equal fuel and the compression ratios are equal [within 14 psi]...............the only variable is software and its reaction to the air temperature and head temperature.

[maxnix]

Yea yea, that's all I ever here you say.. search search search.

No, what I said is read ALL previous posts by Q45tech, if you really want to know. That is the minimum effort which one must expend to learn about the G50.

Like anything worthwhile, one must do the reading to learn. Ever wonder why no physics instructor ever says, "We'll skip thermodynamics because it's so intuitive?" __________________Brian1995 Q45 & Q45t & 2000 Q45

Discover the power of the button!

[Q451990]

Currently looking out for a nice black/black 90-93 Q, that I hope will become supercharged, with one of those nice exhausts you're working on

Would black on grey be close enough? I'm not sure that Black/Black was a color combination in the 90 model year - I've never seen one. "Q1" will be available for about $4K as soon as I can get around to steam cleaning the interior and doing a little touch-up work.

Heath

[Q45Viper]

I had to learn this the hard way....search under USER NAME for Q45Tech. It should not take more than an hour MAX to read all his stuff...well worth it and you will learn important solutions to problems you do not even know about at this point and thereby save yourself a bundle. These are great cars but they ARE expensive to maintain. Making sure you know everything about a topic before getting started helps.

[maxnix]

I had to learn this the hard way....search under USER NAME for Q45Tech. It should not take more than an hour MAX to read all his stuff...well worth it and you will learn important solutions to problems you do not even know about at this point and thereby save yourself a bundle. These are great cars but they ARE expensive to maintain. Making sure you know everything about a topic before getting started helps.

That's it exactly (darn that sxxxh word!), then one can read the other posts by Fred, 1990Q45, etc. that have contributed so much to the knowledge on this site to fill-in the gaps. It is a really worthwhile endeavor.__________________Brian1995 Q45 & Q45t & 2000 Q45

Discover the power of the button!

[PalmerWMD]

dkill: He's selling it for 4k...That leaves a lot of room for extras...And a well maintained VH45de is still a powerhouse at 200k.

Fred...

[PalmerWMD]

All up to you, its always best to look for, what you really want.

Fred..

PS: I'd pick his 200kQ for 4k over any 100k off-the-street Q for $3k , NICO club Q's are superior.

[PalmerWMD]

South Carolina... There goes that idea.. I'm in Arizona

tru its a bit of a hassle.I am not trying to plug him hard or anything, just in general, I must say I wouldnt hesitate to take off from work and fly elsewhere for the right car.

My current Q, I flew to Orlando,FL (from louisville,KY) and drove it back, my last Q before this one was from San Antonio, TX and also driven back to Louisville, KY.

Both were from NICO Members, one was extremely well- maintained with some well executed minor mods and the other had some expensive rare mods on it (one of only 2 former B.A.D. prototypes, still in existence).

Fred...

[desertq45]

Hey guys... funny how a thread can "evolve" into a totally different subject once the "creative juices" get rolling.

Not that I haven't been edified by the info on the early Q and the possibility of having some intense forced induction mods available, but I still need a little specific advice on the chain guide job:

I am having a shop do the work-- probably Euro Imports.

But I have to buy the parts from Joe at IofS... so I was wondering exactly what parts I should get.

I read the post in the Articles forum, but it appears there is a lot of extra stuff that I don't need. For example it lists 2 timing chains, but everyone including q45tech say they will last the life of the car. Also since I am not pulling valve covers (done already)or plenum (atm) I doubt I need the parts specific to that.

I also read q45tech's follow-up to brucepelletier's list of things he replaced so I assume the oil chain and guides should be included, but what about the pump bracket? Crank sprocket? Cam Sprocket? etc.

I remember someone saying that Joe has a kit (waiting for a call back from him) that has it all including the chains and that you could probably return the chains for refund. If so, that might be the easiest way to get everything I need. Thoughts here?

Also I suppose I could use the list as follows:

2x 01121-04711 - bolts for new guides NA4x 11051-60U04 - cam end seals NA1x 13070-60U03 - chain tensioner(RH) $49.901x 13070-60U12 - chain tensioner(LH) $49.904x 13075-60U02 - tensioner bolts $ 5.201x 13079-60U01 - tensioner gasket(LH) $ .562x 13085-60U01 - chain guide $13.182x 13085-60U11 - chain guide $13.181x 13091-60U01 - guide(tension RH) $49.851x 13091-60U11 - guide(tension LH) $49.852x 13094-60U00 - guide bolts NA1x 13510-60U00 - front cover seal $ 5.341x 15041-60U00 - oil pump chain $33.881x 15073-60U00 - oil pump chain guide $ 4.871x 15073-60U10 - oil pump chain guide $30.85

AND skip the following? 2x 13021-60U00 - crank/cam sprockets NA2x 13028-60U00 - timing chains $99.881x 15043-60U00 - crank/timing sprcket NA1x 15044-60U00 - crank/oil sprocket $33.881x 15072-60U00 - bracket oil pump NA2x 13270-60U00 - valve cover gaskets NA8x 14032-60U01 - intk manifold gskts $24.80

Again any thoughts from someone who has been down this path?

Thanks.

[elwesso]

Buying heath's 90Q would be the best buy you could look into.... Perfect maintenance, and its just so incredibly golden!!!

[AZhitman]

dkill - I'm sure you and I, with the assistance of russg (long-time Q/M owner), tgvince (97 Q owner), and Wayne (FX guy), could find something suitable.

Cars here are well-preserved.

[timatt]

So can anyone answer desertQ45's original question regarding the parts necessary for the timing chain job without new timing chains? I'm in the same boat and cannot find definitive info using search.

timatt

[Q451990]

Here's what they used at T3.

1x 13070-60U03 Chain Tensioner1x 13070-60U12 Chain Tensioner4x 13075-60U02 Tensioner Bolt 1x 13079-60U01 Pump Gasket2x 13085-60U01 Chain Guide2x 13085-60U11 Chain Guide1x 13091-60U01 Chain Guide1x 13091-60U11 Chain Guide2x 13094-60U00 Tensioner Bolt1x 13510-60U00 Front Crank Seal1x 15041-60U00 Oil Pump Chain2x 15073-60U00 Chain Guide1x 15073-60U10 Chain Guide

Heath

[desertq45]

timatt,

Joe at Infiniti of Scottsdale sells a kit to do the guides. I went down and talked to him about this and also spoke to Scott at Euro Imports (formerly of IofS and is pretty damn knowledgable, having personally done this job over 100 times) and the concensus was this:

Use everything in the kit with the exception of the timing chains, oil pump chain and oil chain guides. (Oil pump stuff is optional, probably a peace of mind thing rather than a "will fail" thing since neither sources had heard of or seen an oil chain fail and the oil guides are steel, not plastic like the timing chain guides that WILL fail). Total cost for my parts was: $236.35 plus tax and labor to do the job was $800.

My list from the kit contained the following:

1x 13070-60U03 Chain Tensioner1x 13070-60U12 Chain Tensioner4x 13075-60U02 Tensioner Bolt 2x 13085-60U01 Chain Guide2x 13085-60U11 Chain Guide1x 13091-60U01 Chain Guide1x 13091-60U11 Chain Guide1x 13510-60U00 Front Crank Seal1x 999MP-A7007P Silicone

Heaths list had these additional parts:

1x 13079-60U01 Pump Gasket2x 13094-60U00 Tensioner Bolt1x 15041-60U00 Oil Pump Chain2x 15073-60U00 Chain Guide1x 15073-60U10 Chain Guide

Again, the additional parts listed by Heath were also recommended by q45tech as something to do while you have the front of the engine unbuttoned, but I checked the parts during the job and felt it wasn't necessary in my case. As a matter of fact, my chain guides looked great, no stress cracks or anything. At 138k I guess I can consider myself lucky or sing the praises of frequent oil changes with Mobil 1. But since those definitely do and will fail, it is requisite to do them.

The other aspects to consider include valve cover gaskets (I'm told that to change the chains you need to remove the covers but to do guides you do not...) if they are leaking. I had just done mine so we didn't redo them. Unfortunately I hadn't found this forum when I did them and I also did the front seal, which done with the guide job... had I known about the guides then, it would have saved me some $$.

Also think about the belt tensioners, steaming/rebuilding the radiator, belts, ps hoses, rack boots, tension strut bushings, etc. that may be minimal labor while the job is being done, but necessary maintenance. If you have ps hoses that are leaking, be aware that the high pressure side is pricey... about $200. Also there is a multi-bend metal hose that goes to the rack that may/may not fail that is also pricey but I'm told it can be rebuild for about $50.

Sorry for the lengthy post, but hopefully the info here will be sufficient to help you decide what you need to do. Just be sure to use a Mechanic that has done this job before and is familiar with the Q... that is my strongest advice. Good luck.

[DAEDALUS]

The overwhelming consensus is to replace the oil pump chain and guides. While the guides are metal-backed, they are also nylon-lined, and 1 of the guides also serves as the chain tensioner. It eventually wears, leaving the chain *way* too loose.

[desertq45]

I think the thing to remember here is that the labor to get into the guide job is significant and it never hurts to spend an extra $100 on parts to prevent having to spent the $800-1200 again later to open her back up.

In my case, I had a veteran Infinity-trained technician who worked on the early cars when they were new, and now currently operates his own shop and has personally seen a multitude of Q45 guide jobs on these same "early Q's" give me his opinion on the oil guides/chain. Keep in mind this was not a generality, but advice on MY SPECIFIC car. In my case. the guides showed little wear and the chain tension was in spec. thus the decision to forego the replacement.

This determination may or may not apply in your case. As daedalus pointed out-- they do wear and if in doubt, now is the time to replace them. If your uncertain, just replace them and sleep well.

[timatt]

Thanks for the advice: I ordered the parts from Joe today. I'll call him back and order the pump chains and guides.

You guys rock!

Timatt