Now I've little choice but to drive it, loose crank or no

[Guest bastaad525]

As if this car hasn't already sucked my every penny and every last ounce of patience from me....

 

 

Tranny's out of the car, found I do need a new clutch, flywheel resurfacing, and a few other parts. But the biggest blow was when he showed me that my crankshaft is moving back and forth...

 

I'd say it's got a good 1mm of play in there back and forth... I dunno who was keeping track but when I did my 'partial rebuild' on the block, I only replaced the rings and rod bearings, the crank stayed in the motor. I get what I pay for I guess. I have no idea how long it has been that loose, if it's gotten worse or whatever....

 

 

So tell me, just how f**ked am I this time?? I am HOPING that it's just a case of worn bearings... not a screwed up crank... and I'm further hoping that since I run Mobil 1 oil that this will greatly slow down the rate of wear and keep this problem from becoming too huge too fast. I know I drove my camaro with a hell of a lot more play in the crank for a long ass time (crank pulley could move out by almost half an inch). I do worry this may cause problems with the CAS since I have an '81 which relies on the crank pulley for signal. So far I dont think I see any signs of this or any adverse effects of the loose crank... I never would have known if he didn't show me.

 

any idea how long I may have??? What risks am I taking driving the car like this? I DONT have the money to rebuild the block and dont have the money to buy another one and swap it. I've already relegated the Z to not being driven daily anymore, maybe once or twice a week, though this tranny/clutch work is taking out a sizeable chunk of the money I WAS going to use to buy another car.....

[JMortensen]

The acceptable limit for crank end play is .012 according to How to Rebuild.

 

Why don't you just roll in some new main bearings? Not the easiest job getting the main caps off, but not impossible, and you know you've already got good rod bearings in there.

 

One thing that will help it keep from getting worse is to run a stock clutch disk. You can run your big pp, but run a stock disk. Much less thrust bearing wear.

 

Jon

[Guest bastaad525]

Heh too late I already bought the Daikin clutch set and it's being installed right now. Dont think a stock clutch would hold the power I'm putting down and definately not the power level I am aiming for... maybe I should say WAS aiming for???

 

It's definately moving more than .012 of an inch

 

it looked somewhere between .5mm to maybe even as much as 2mm... was hard to tell but it was enough that I know it wasn't good

[Guest bastaad525]

Oh and the pilot bearing was cracked pretty badly... that mean anything?

[JMortensen]

I think you might be surprised what a strong pressure plate with a stock disk is capable of. My all stock setup started slipping REALLY bad when I got the trips, now it holds good even going to 4th at 7000 rpm with ACT and stock disk. No matter though since I guess you've already got your replacement. I thought the Daikin stuff was similar though. Strong pp and stock type disk.

 

Never heard of a cracked pilot, but at least it made removal easier, right?

 

The L series cranks are really strong, if you're really low on cash get new bearings on the mains and recheck the endplay would be my suggestion.

 

Jon

[BayAreaZT]

I think it's the main bearings too. I really doubt it's the crank. Those suckers are stong. If you want to be sure though, you should have the journals and straightness checked on the crank.

[Guest bastaad525]

Doesn't matter much... I dont think getting a crank would be too much of a big deal, costwise they're really not expensive or rare, the big deal is that I'm still in no position to be able to do this kind of work myself, and whether the bearings or the crank, the labor price is gonna be high and probably about the same either way. Would be cheaper to find another good block or complete motor and swap it in, and I may be able to actually do that myself in a day, now that I have made friends with a couple of guys with cherry pickers and their own space to work. I'm having trouble understanding one thing, is it possible to replace the crank bearings w/o removing the engine? What EXACTLY would be involved? Please as much details as you can give me as to what needs to come out and what work is necessary to do this would be very helpful... maybe it IS something I can arrange to do and not cost a fortune?

 

I thought the Daikin stuff was similar though. Strong pp and stock type disk.

 

The Daikin disk he showed me looked very similar to my ACT disc, it was a six puck, metallic type disc, except for the Daikin had springs in the middle whereas the ACT did not. Luckily I did get ahold of the shop in time, and was able to change my 'order'. So now he is installing a stock replacement clutch disk, and the Daikin pressure plate, which he says is definately stronger than stock. So you guys DO think this will be able to handle the relatively modest power I'm putting down right?

 

As it stands now I'm no longer going to be driving the Z every day so I'm gonna try my hardest not to let this get to me. I'm aware of it now, that's good at least. The Z will only be driven a couple times a week and not very far... I'll just keep my eye on the crank play and hope that with the synthetic oil and stock disc the wear will be slow enough as to allow me plenty of time to figure which way I'll go and save up the money w/o straining myself. This car has made me strain too much and I'm not gonna do it anymore, the car will be sold first. I drove my camaro with a LOT more crank play than this for a long period of time before it finally started causing problems (a very strong vibration which started damaging the torque converter shaft). So I'll just drive it and see what happens....

[Guest bastaad525]

Oh and not that it matters much anymore (all my plans for increased power just went out the window until this crank problem is fixed... I/C still gonna keep gathering dust!) but if this stock disc/daikin plate combo can hold this much power, do you guys know how much headroom I have whenever the day comes that I do shoot for more power? What do you think the max limit will be before going back to a stronger disc will be necessary?

[Guest bastaad525]

Grrrrrrrr it keeps getting better. They can't even get the new, stock clutch plate in w/o a problem... apparently some part of the clutch plate is rubbing on the flywheel bolts??? Odd seeing as the machine shop that just resurfaced the flywheel said that the the flywheel thickness was within allowable specs...???? So they sent another flywheel and though it was supposed to be a zx 2+2 flywheel the bolts wouldn't even fit in it at all....

 

Why.... why can't this damn car just once, let something be only what I think it will be... why is it every time I go to fix one thing I find that 10 other things need to be fixed as well? I feel a for sale ad coming on again... trying very hard to resist but man how many times can I easily drop $1000 on stuff like this? All this just because I wanted my tranny and rear main seal to stop leaking, and now I find my motor is f**ked as well. And now they can't even get the clutch back in.

[olie05]

I'm thinking to replace the main bearings you have to drop the crank shaft, so you have to take out that cross member right under the engine, but then that holds the engine up... What you have to do is hoist the engine with a chery picker, drop that cross member and then get to work on the bearings. Personaly, I would take the engine out and work on it outside of the car...

 

I can sympathize with you... My car was running perfectly before I took it apart (although the block had a rod through it) But now with everything connected EXACTLY as it was before, with no modifications to the electrical system, I'm not getting any spark or fuel. I'm thinking about that for sale sign too...

[Tim240z]

You can replace the bearings with the motor in the car....It's not as easy obviously, but very do-able...

[Guest bastaad525]

It's not as easy obviously, but very do-able...

 

 

Not in my case Heh Tim you of all the guys here ought to know by now that asides from my apartment situation, I kinda suck all around as a mechanic... at least for the more complicated stuff. No way I would try to do this job myself with my "Murphy's Touch - every he touches can and will go wrong"

 

I dunno, I'll figure out what I"m gonna do... Like I said I may just keep my eye out for another motor... maybe even find a used one and get a full rebuild on it, the right way this time. If it just keeps beating on me though (and really... has it shown any sign of letting up?) I'm gonna raise the white flag sooner or later.

 

Asides from sitting there and measuring the amount of play there is every so often, are there any signs I should look out for that will tell me that it's getting TOO bad. Or to put it another way, if I had never found out that it was like that... never dropped the tranny or anything, and just kept driving it like that, how would the problem most likely first make itself known?

[Ben]

I can sympathise with your predicament. My 240Z restoration took 5 years, and for most of the last year my L28ET was sitting, unused, in the shed. Well, after driving it for a few months I've discovered that the exhaust stem seals are failing & as a result it's burning a reasonable amount of oil during over-run. Grrrr....

So this brings forward the ported P90/forged piston/big boost conversion that I was hoping to put off for around another year in order to 'finish' freshening up my Skyline (one day I'll get he seats retrimmed & the A/C fixed!)

 

BUT - I suggest you get the crank thrust play fixed ASAP, as it wil be adding extra load to the rods, pistons, bores & balancer as wel as causing your ignition timing to wander all over the place. This is a cause for concern, you don't want to have to replace the pistons & have the engine re-bored due to scuffing.

[johnc]

You can run your big pp, but run a stock disk.

 

I think you have that backwards. The pressure plate exerts force on the crankshaft with the clutch transmitting torque to the trans input shaft.

 

1mm (.0394") of end play is not good. The thrust bearing is going fast and you'll be looking at replacing the crank very soon. Been there, done that.

[JMortensen]

You can run your big pp, but run a stock disk.

 

 

I think you have that backwards. The pressure plate exerts force on the crankshaft with the clutch transmitting torque to the trans input shaft.

 

I thought it was the violent grab on the clutch disk from the bronze or iron pucks that took the thrust bearing out. The pressure plate is attached to the crank via the flywheel, so I don't understand how it would cause more wear if it gripped hard but didn't chatter like a puck disk does.

 

EDIT--just figured it out. You're pushing on the end of the crank when you press the pressure plate. Still, I've known LOTS of guys with heavy pp's on L series, and the only ones that have had thrust bg probs were the ones with the puck clutches. There has to be something about shocking the crank with the clutch that causes damage, especially when they start to chatter.

 

Jon

[Guest bastaad525]

you guys are confusing me... PLEASE dont tell me I just made the wrong choice with this stock clutch/heavy duty pressure plate....

 

BUT - I suggest you get the crank thrust play fixed ASAP, as it wil be adding extra load to the rods, pistons, bores & balancer as wel as causing your ignition timing to wander all over the place. This is a cause for concern, you don't want to have to replace the pistons & have the engine re-bored due to scuffing.

 

Problem is dude I really dont have a choice. I just dont' have the money to pay to get this done right now and cannot do this myself for a number of reasons. I can only do the next best thing which is to severely limit the amount of driving I do in the thing. Unfortunately, this trans/clutch fiasco is costing nearly twice as much as I'd originally planned due to other problems popping up (which ALWAYS happens with this damn thing) and is taking a significant amount of cash out of the savings I was going to use to buy a beater/daily driver. I will be 'borrowing' the heck out of my wifes car, but I can't use it every day, so there will be times that not driving the Z is not an option, at least until I can save up again, a good enough amount to get myself something I can drive every day.

[JMortensen]

IME you've made the right choice on the pressure plate and clutch. Like I said, I've only seen damaged thrust bearings on puck clutch equipped L series.

 

Going to super cheeseball hack mechanic mode--

 

Couldn't Bastaad just pull the middle main and replace just that one? That's where the thrust bg is. Mark the cap so you don't flip it around when you reinstall it.

 

I'm sure you already know that it's better to fix it right Bastaad, but maybe this would just get you back on the road...

 

Jon

[Guest bastaad525]

Heh funny thing is... if I hadn't been so anal about a leaky rear main seal... I'd still be ON the road, never knowing that this was a problem. I WISH I knew how long this has been like that, or how quickly it's been getting worse. I'm willing to bet it's been like this for a lonnnnnnng time.....

[technicalninja]

Dirt simple. After clutch job finished (tranny helps support engine) remove pan. You do not have to disco engine mounts. after pan loose from block turn crank from front pully until pan can be removed towards tranny. Remove oil pump pick up (2 8X1.25 bolts) loosen all main bolts except last journal 1 turn only (last journal is very difficult to remove in car- I would leave alone) remove main caps one at a time (lossen bolts and use bolts to wiggle cap untill it releases from block) Replace bearing in cap. look at exposed crank main journal. The ends of the upper bearing will be exposed- one side will have a locating tab which fits into block. push other side of bearing up and bearing will rotate on crank allowing replacement. install in reverse order being carefull that locating tab fits into recess in bearing journal and bearing shell is not angled in block. Lube crank side of bearing with a little lubri-plate or eng assembly lube. reinstall lower cap and hand tighten main cap bolts evenly. finish one journal before moving to next. The center journal (and the rear more so) have larger shoulders where they fit into block. Nissan machined removal holes into both of thes journals. Thread a 8X1.25 bolt into hole and use a small prybar (large screwdriver) to remove (once again wiggle cap- do not try to remove in one single pry). Slipping center main in is tighter but can be done.

Make sure you replace bearings with identical ones as top and bottom are different and widths change with journal (center journal is obvious as it has thrust built on) first and last journal are slightly wider that the rest, block inserts have oil groove in them, cap inserts do not. This may vary with manufactors.

Total cost for all parts could be below 50 dollars and although this is not a "correct" repair it could get you many miles down the road.

It would take me an afternoon to replace bearings and can easily be done on jack stands. If I went to all of the trouble to remove engine I would do a correct job and have crank checked by machine shop and complete lower end rebuid as nec. Very expensive and time consuming.

Final note- use a good torque wrench to torque all main bearing bolts.

Hope this helps. Good luck

[Guest bastaad525]

*sigh* but it's NOT that simple. I do appreciate your detailed explanation though. I'd need a lot more tools than what I have now. I dont even have a good jack or set of jackstands simply because I'm not really allowed to work on the car in my apartment parking lot, and dont really have any other place I could work on it, not usually anyways. My friend that helped me replace the rod bearings and rings vowed he'd never do anything like that again... it was a PITA and pain on both of us. Second... I dont trust myself on anything that major... if there is a way I could screw it up, you can bet I probably would. Third, I'm POSITIVE it wouldn't be as simple as you outline it, if only because of the fact that this car has NEVER failed to reveal another problem, sometimes MULTIPLE additional problems, whenever I'm in the course of trying to fix one. Just like what just happened with this tranny job. And by the way, I thought you had to undo the engine mounts and raise the engine no matter what to get the oil pan out?

 

I will look into this, however. I'll get a tally of costs for the bearings and tools I would need, and take a good long look at diagrams in the haynes manual to get an idea of what all I'd be dealing with. If there is a way that I can do it, I probably will. Even if I wanted to pay someone else to do it, the 'cheap' guys I used to rely on I dont trust any more, too many botched jobs now, and a real shop probably wouldn't even bother with this, because you said, it's an 'incorrect repair' and they'd be too worried I'd be back in a month complaining that they screwed up or something.