Guide Chain Labor

[SFBayQ45]

I've inquired thru a couple shops about the guide chain job and each shop gave me the identical labor hour charge: 23.8 hours. This doesn't sound right.

Quote lists:

Labor - Replace (incl R&R timing cover) 23.8 hoursLabor - Note: With AC, add 0.7 hoursLabor - Note: With PS, add 0.5 hours

I remember Jesda's chain guide job being done in as little as 5 hours. What's the rational for the added hours?

[DAEDALUS]

Most likely includes opening up the valve covers and replacing the chains. Without the chains, I would say fair labor is closer to 12 hours, give or take, without pulling the oil pan.

[DAEDALUS]

An expert tech who does at least one set of guide replacements per month [say has done 30 or so on the Q] and has every possible tool and a few he designed and invented himself PLUS A LIFT can replace the guides/tensioners in 6 REAL hours......without taking more than bathroom breaks. Such rushing has a 10-20% chance that the timing will slip turning the 6 hour job into a REAL 13-15 hour job since then the valve covers and other covers will need to be pulled.

We compromise and charge for 10 hours labor and eat the possibility of a mistake [turning some jobs into losers].

The dealers go by the book and replace the chains making it a 25 hour job..........[a real 2 day job]. We quote $1,000-$1,200 parts and labor [on the simple duide replacement] and require the oil pan be dropped and cleaned IF we cannot find all the broken guide pieces [ this adds $500] [7 billable hours].......maybe 4.5-5.5 real hours to drop the pan with every thing already off!

A few hours are consummed in mandantory cleaning the covers of varnish and the car is tied up on the rack [or pushed somewhere] while the RTV dries before cranking.

We have 7 certified techs and only 2 are really qualified [ want to do this tricky job].

We get them towed in [from other States] all the time where someone has tried and given up when the timing slipped. Not knowing what to do next.

Our most experienced tech has done over 100 guide replacements and only had 3 slip in the last 3 years, the other experienced tech has done 10 and had 2 slip.

[Q45tech]

You are confusing a total drive chain and guide replacement [25 hours]with just a guide replacement 12 hours.

To replace the drive chains the valve covers have to come off [adds 5-6 real hours] then the changing of the chains and retiming 3- 6 real hours more for idiots who make mistakes].

We charge 12 shop hours for just the guides plus parts.

12 shop hours can be done in 8 hours by experts who hustle.You still get to pay the 12 hours.

Most dealerships won't do the "just guide" job because of the chance that timing will slip then they have to do the additional 12 hours for nothing.

My expert can sometimes do one in a real 6 hours but he averages 8 hours [does nothing else in a full 10 hour day] because of the stress it creates to do just a guide only job!

Most expert techs can do 13-15 book hours per day in 10 real hours of work. You never pay for actual stop watch time otherwise the clock would start the minute you drove in and talked to the first employee.

You could drive to Iowa, San Diego or Atlanta and save some money.

[DAEDALUS]

LOL Sacked by his own post! Sorry Dennis.

[SFBayQ45]

Thanks Dennis for the differentiation in labor...you're the MAN Q45tech.

Thanks DAEDALUS for sparing me from searching any further. I attempted to look for Q45tech's considerable responses regarding this issue for the last hour or so and I couldn't find that informative description...until you saved the day.

[mtcookson]

how easy is it for the timing to slip when doing this job? how about if the engine was out of the car?

[DAEDALUS]

You have to make a compromise between having enough chain tension to maintain timing and having enough slack to work the new, larger guides in place. They're deceptively tricky...if you position them right you could probably remove the tension completely and the cams won't jump (right away). Then suddenly, with you not even touching anything, CLA-CLA-CLA-CLACK!With the engine out, you have more room to work and more options for securing the chains.

[Q45tech]

When you remove the radiator and use a lift you have the same amount of front exposure to get your hands head upper body in front of engine...........spending another 10-12 hours to take the engine out and put it back in defeats the purpose. Guess it you had to pull the oil pan you could count 3.5- 4 hours of that process but still 8 hours longer to pull the engine.

[Jesda]

http://www.q45.org/guidereplacement.html

A few dozen photos of the chain guide job Scott Jackson did. He did a fantastic job, and the Q runs stronger than ever.

-Jesda

[mtcookson]

My plans are to swap one of these engines into a Datsun 280Z so the engine will be out in the first place. If it hasn't already been done then I'm definitely planning on changing the guide before it ever comes close to being put in the car. Thanks for the help!

[elwesso]

MT... You might consider a 94 engine, and you could mod it to make it 90% as powerful as the 90-93.....

I wonder if thered be any gains by switching 90-93 loewr intake runners on a 94.....

[mtcookson]

I've not been able to find many deals on the 94 and up Q's as I've been able to on the 90-93's. (mostly 90 and 91 are good deals). I don't mind doing the work since the swap itself will probably take a while. (as well as setting up the TTZ transmission)

So, do these things truly pull ~310 hp and ~330 ft. lb. of torque??

[elwesso]

Your numbers are pretty much right on... Whenever people ask me my HP numbers, I say 300.....

[mtcookson]

Awesome! Heck, that kind of power in the Z would make for some tire burning fun and some good 1/4 times.

[BadQ45t]

You should take a trip down to LA and get Daedalus to do the work for you. I had my Dad's 92' and was going to have him do the job until we decided to pass on the car due to gas mileage and wife's lack of interest in the older car. I miss that old girl, but I had spoken to him about doing the job very reasonably, Dae- you still doing these jobs in the garage??

The Bay Area is so expensive to get cars worked on, another reason we passed on keeping Dad's 92' in working shape.

[DAEDALUS]

Dae- you still doing these jobs in the garage??

Unfortunately no. We bought a fixer about a year ago and most nights and weekends are devoted to the house now, aside from my NICO time, which is not insignificant. My own Q, unbelievably, has been patiently waiting in my garage since around February for a good amount of work to be done...rear seal, transmission sensor, oil pan gasket and knock sensors. Ironic that I bought a house so I'd have the room for all my tools and room to work. It is awesome though. I've had a few friends' cars over for some minor work now and then, and having a big garage just plain owns. After the house is finally done--whenever that may be--the lift goes up and the Q will once again be my biggest priority.

[SFBayQ45]

BadQ45t - good suggestion on going down to meet DAEDALUS. But you also saw his explanation above. I was in that same line of thinking when I approached DAEDALUS for the chain job a couple weeks ago, but he had refuse the work for a legitimate personal reason. Good luck DAEDALUS on the house repairs...

[ardvarkus]

how easy is it for the timing to slip when doing this job? how about if the engine was out of the car?

Same diff. With the rad, fan, hoses, etc removed there is plenty of working room.

Trick is to tie wrap the chains in place on EACH sprocket- keeping slack in the middle to allow the guides to be removed.

The problem is that in ANY position, there is ALWAYS tension one way or the other on the chains- release pressure and the cam will rotate to a more relaxed positon (possibly (likely) jumping a tooth in the process.)

Not the end of the world if it jumps... (but if you don't know it jumped it may be) Resetting is a PITA and requires careful study of the technique in the manual (and a review of posts here.)

Ard

[mtcookson]

MT... You might consider a 94 engine, and you could mod it to make it 90% as powerful as the 90-93.....

I wonder if thered be any gains by switching 90-93 loewr intake runners on a 94.....

Found a low cost 94 online. What are the differences between the 90-93's and the 94-96's that make the power difference (if i'm understanding you correctly). And by 90% as powerful, do you mean compared to the stock power or total power output? I'm confused by what you said (which isn't too uncommon) lol

[elwesso]

Bascially the difference in the "increased power" of the 90-93 vs 94+ is...

1. Emissions (not sure what they changed)2. transmission3. Lower intake runners

I think if you dynoed a stock 94 engine and a stock 90 engine, both in equal running condition, they would dyno within 10hp... hardly worth anything, IMHO, especialy if you plan on modding......

[mtcookson]

Oh... well if that's all then heck, I'd probably go with this 94. Do the 94's still have OBD1 or did those upgrade to OBD2 with the newer emissions stuff. Do you happen to know what emissions items were added? Can they be easily removed?

Sorry for all the questions. Just making sure I know what I'm buying before I'd spend the 2500 dollars. Thanks for the help!

[mtcookson]

Just bumping the thread. If the 94's do still have the OBD1 ecu I'll most likely go pick this one up.

Anyone know when the OBD1 to OBD2 crossover occured?

(sorry for hijacking the thread) lol

[IvoryJ30t]

96

[maxnix]

Injectors on later cars were rotary disc instead of single pintles on earlier. There was a move away from the early sodium filled exhaust valve stems to solid stainless steel ones. MAF connectors and other changes/updates are present also.

[mtcookson]

cool... well i think i may go take a look at this thing then. it has 188,000 miles on it. still think i'd be safe getting it with that many miles on it?

[IvoryJ30t]

as long as your up for a refresher. might be too high of a mileage if your not gonna freshen it up or if your gonna boost it.

also, i wouldnt open up the motor if your not very experienced.

this motor requires the ability to measure to the .0001 of an inch.

i get to dust off my micrometers. need to get my gauge blocks certified.

[mtcookson]

at the moment i would just toss it in and drive it around with minimal mods. down the road i'd toss in the some custom pistons and the works then turbo it. i dunno... i may still wait and see what else i can find.

[Q45tech]

The CAS/subcas is different on 94-96 vs 90-93.........the harness and connector shape so something will have to be made modified [the signals are the same] just a newer design shape........non interchangable without work.