When Do Chain Guides Need Replacement?

[oxs1]

I have a 91 Q w/182k and i am wondering when the guides need replacements.

[Q451990]

About 50K ago judging by when mine failed. I have personally seen failures as early as 77K, and we've heard of them very rarely in the 40-50K range. It's really hard to say what has the greatest impact on failure - age, heat cycles, miles, oil change habits, driving habits? Best plan is just to replace them since there's no warning before they go... just catastrophic engine failure.

Heath

[elwesso]

Just look at Jesda. His Q was maintained PERFECT. His engine was so clean id eat spaghetti off it... He was at 185kish and one guide was broken, and was probbaly only a few WOTs away from failure.

Your on borrowed time..... I would include it under 120k maintenance....

[AZhitman]

Yesterday.

'Nuff said?

[PalmerWMD]

Several members have experienced failures around 100k.

Fred..

[Jesda]

Thread with photos:http://nissaninfiniticlub.net/...saved

[maxnix]

Search under timing chain guides or read the Infiniti Article entry.

What else can we say?

[Q45tech]

A 91Q is worth $500 to $750 with a blown engine as a parts cars after you tow it to the buyer. Assuming you can find someone who wants it.

[1992Q45A]

Mine went out under 100k...

You really squeezed the most you could out of yours.. I guess you should decide if you want to keep it or just run it till they die.

[DAEDALUS]

You might get another 100k out of your engine if you do the guides. If your car's been in S.D. its whole life you might be lucky enough to not have to drop the pan.

http://www.nissaninfiniticlub....12551

[nuQ]

my driver side guide toast at 100k, had to fish the parts out of the oil pan!!!! you really are one wide open throttle to total destruction of the engine at this point!!!! if you plan staying with the Q, get the guides done,,,,if not, drive her till she dies,,,,but you'll get no money at that point!!!

[Jesda]

Owning this Q and servicing the guides has been expensive, but MUCH cheaper than a new vehicle with $200 payments + full insurance.

It boils down to commitment. Stay in for the long haul or sell it and move on. (Of course, there's pragmatic issues like how well the rest of the vehicle was maintained. My motor, transmission, and body are in excellent condition.)

In a neighborhood of new BMWs, Cadillacs, and Lexuses, I still think I have the best damn looking car on the block.

-Jesda

[SFBayQ45]

http://www.nissaninfiniticlub....12551

DAEDALUS - That is an extremely informative thread you've attached. I appreciate that thread you've started back in 2003.

Can anything else be done/changed at the same time to cover overlapping work in order to reduce cost in the long run?

[Q45tech]

Not really other than the front main cranksaft seal which requires replacement every 120,000 miles or so. Drain the radiator and replace drive belts and check all idler pulleys for bearing noise.Little more room to get at power steeing hoses.Pull radiator and clean fins and ac condenser fins of dirt.......look inside the coolant anode [metal pipe betweeen lower rad hose and its upper mate] for corrosion build up.

Find some independent expert who will only charge you $900-$1,000 per day [for labor] and work is ........ off regardless of what he changes.

Buy and supply your own parts for a 25% [parts saving].

You would be surprised at how much work can be done in 3 days [with a properly motivated technican] with $2000 [worth of discounted parts*] $4,700 becomes more like $7-7,500 at dealer prices .

Chain guides, oil chain, plenum hoses, knock sensors and harness, injectors, O2 sensors, shocks, transmission mount, upper links, tension rods. oil pressure sensor, ps hoses.

[oxs1]

i just had a minor engine rebuild and before i had it rebuilt i had a vibration at lower rmp like at idle. How much time do you guys think my q has left in it given that i do not replace the guides which will cost me $1000 or if i do my chain guides how long will it last?

[Q45tech]

Well I have 264,000 miles and we have many customers in the above 200,000 mile category.

Everything gets tired after 250k and even mine is starting to drop compression, I feel I can get 300k another 36k or 2 years on my engine but it has had extreme maintenance and 60 synthetic oil changes in 14 years some more frequent than every 90 days.My guides replaced at 100k.

At 182k with some expenditures you should have no trouble getting 250k depending on present condition.......you might have to spend $3,000 on engine related items. Have the plenum hoses and knock sensors plugs be recently changed, valve covers sealed, front and rear mains replaced , injectors are the question mark.

California is so iffy because of gasoline

[natsoundup]

I know I am one of the lone voices against the replacement at that advanced engine age.

If you recently have spent the money on a transmission rebuild and some other critical parts, I would go for it.

Most know that I made the decision to forego the chain guides, give the car to my son..... and got myself a 94. When the 90 finally does go because of chain guides or transmission...I will part it out.

While I love the cars, if you think maintaining one Q is tough, try two... it becomes an economical decision rather than an emotional one.... plus I have had the 90 Q for 11 years... no complaints...

[Q45tech]

We tried to get the word out in the late 90's when the cars were just at 100k to prolong the life till 250k.............seems cheap insurance to ensure the ultimate demise will be from ring wear [gradual loss of compression] rather than bang on the interstate some rainy night.

Of course we are seeing more rod bearings go [rod knock] from abusive oil change intervals now.Buying a pig in a poke can be risky as mucho damage could have already occured.

People just can't resolve 90 day oil changes in the beginning to ensure 300k life.........can't won't think about a 300k car.