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Thread ID: 81485	2007-07-29 01:20:00	Auto gearbox problem	tut (12033)	PC World Chat

Post ID	Timestamp	Content	User
573841	2007-07-29 06:30:00	that works here too...	SurferJoe46 (51)
573842	2007-07-29 06:34:00	Sorry to confuse you plod. I was referring to my Mitsi about filler holes and yes It occurred to me I might have drained the gearbox instead of the sump. that would account for the problem. However a quick check indicates this was unlikely. I will check again though as it is the only sensible possibility. Before I get too carried away I will change the engine oil again making sure it is the sump I open, top up the gearbox and see what happens.	tut (12033)
573843	2007-07-29 06:46:00	There was no sign of the 'trannie' drain but I know a sump drain when I see one (I think) I agree that it will probaly go ok when I make sure of the fluid levels and get the right drains if that is what happened. All your inputs have been valuable thanks.I need to be told frequently that I am stupid. Grounds me for a while. I have rebuilt a few manual boxes over the years but keep away from autos as I do from modern cars where I recognise nothing under the hood nowadays. SJ, I enjoyed your recent lessons on auto boxes. In fact I enjoy all your posts, it makes me homesick as I spent a lot of time in Manhatten Beach.	tut (12033)
573844	2007-07-29 06:57:00	Sorry to confuse you plod. I was referring to my Mitsi about filler holes and yes It occurred to me I might have drained the gearbox instead of the sump. that would account for the problem. However a quick check indicates this was unlikely. I will check again though as it is the only sensible possibility. Before I get too carried away I will change the engine oil again making sure it is the sump I open, top up the gearbox and see what happens. thats alright, not confused. I was just stating a point. What was common knowledge about cars 15-20 years ago, no longer applies now for home mechanics and in some cases this means even oil changes	plod (107)
573845	2007-07-29 16:58:00	There was no sign of the 'trannie' drain but I know a sump drain when I see one (I think) I agree that it will probaly go ok when I make sure of the fluid levels and get the right drains if that is what happened . All your inputs have been valuable thanks . I need to be told frequently that I am stupid . Grounds me for a while . I have rebuilt a few manual boxes over the years but keep away from autos as I do from modern cars where I recognise nothing under the hood nowadays . SJ, I enjoyed your recent lessons on auto boxes . In fact I enjoy all your posts, it makes me homesick as I spent a lot of time in Manhatten Beach . TY . . . Sometimes the Auto trans drains from the differential in front wheel drive cars too . I think that has been changed in the latter years as it was a little confusing to the "mechanics" in the jiffy-lube circuit, who . . . let's face it are all BK burger-flipper rejects anyway . Make sure that you have ATF in MOST differentials (FW drive) as they are mostly all designed for that fluid . It seems strange, but the old days of 85-120 EPW gear lubes is all but gone for the sake of economy . Thinner lube fluids mean less parasitic drain on the engine and better fuel mileage . Some rear wheel drive transmissions (manual types here) still use 85-120 EPW, but they are rare indeed . As to the possibility of ATF migrating to the engine lube oil . . not likely . There is always either the clutch/flywheel between the engine and the transmission or the torque converter/flex plate that all but totally obviate that problem as impossible to happen . If oil even tried to change places, then you'd have a severe leak out the bottom of the bellhousing and that's gonna flow all over the floor anyway . Without that happening, then you don't have a seal failure to worry about . Overfilling an engine USED to be (another old wive's tale here) the cause of blowing out the seals in an engine . The only possible scenario would be the anecdotal evidence of a large puddle under the engine after such mistreatment . What REALLY happened was more like this: The seal(s), made of wax-impregnated rope, would already be loose and brittle and the overfilling would take the oil level to a height where it was not normally allowed while the engine was at rest and it would pour out . . evidence enough! Bah! The seals were already bad and the extra oil would leak down to a more normal operating level in a while anyway . . . . just sheep-poop (I try to use local color for youse guys to understand the silliness of the theory . . does it help? You seem to have sheep in abundance and I figger the reference is an easier mental picture for youse . ) As far as hydraulicking an engine by severe overfilling of the crankcase . . well, I guess it's possible if the oil actually got into the top of the cylinders and stopped the piston from coming to top-dead-center somehow . To actually hydraulic an engine means that a non-compressible fluid or solid (ask me about peanut husks someday) had to get into the combustion chamber keeping the piston from making it's appointed arrival . A bent rod, broken ring lands, cracked piston, brineled rod bearing surface or busted crank (not too likely nowadays) would be evidential . The hard part is actually getting the oil (in this case) onto and in the top of the pistons/cylinders . It COULD happen if the KV or CV side of the crankcase ventilation circuit entrained vast amounts of oil from the valve cover (CV) vent or the top of the closed block (KV) side . The CV side is operated by vacuum from the intake manifold and MIGHT just be able to suck oil ot of the engine common area called the crankcase if the oil was actually high enough to get to the inlet of the valve . That valve is incorrectly monikered as the PCV valve, here "valve" is redundant as the letter "V" in PCV stands for valve anyway . The KV side is just a more or less atmospheric passageway that keeps the pressures in the crankcase and the air filter box close to equal for reasons of emission control and purging the crankcase of volatile and sulfurous fumes, prolonging the life of the less noble metals in those areas . If you see a lot of oil in this system, you've got or had problems . Clean it out or not, but watch it for a while to see if it continues to get oily . Oil SHOULD NOT entrain and gather here . It is a bad sign usually of worn rings, broken piston . . etc . . . all sorts of nightmare things too nasty to think of now . An oil-soaked air filter is primary evidence of trouble here . As far as the transmission being overfilled . . the same fairy tales about blowing seals is told here too in the event of overfilling . Think of it this way: The transmission DOES NOT have a pressurized internal case . The ONLY place for high pressure is in the charged/pumped fluid areas that operate the clutches, bands and the torque converter and valve body . There are some passageways that have high or extremely high pressures, but they are not usually controlled for leakage by seals as you perceive them anyway . Besides, leaks from them would all be internal and you'd never see them at all . Again, the transmission is typically atmospheric pressure inside it because there are vents on the case for just that purpose . Some are hidden inside the bellhousing and some are obvious on top of the case and look like a little metal mushroom with a jiggly lose cap on it . If you see fluid from here and you KNOW the level is correct, then you likely have something whipping the ATF into a frenzy and it is just foaming out of the vent . That is not likely a good sign . SOME of the modern overdrive AT's have an overrunning clutch that is applied when the transmission drops from overdrive/lock-up to a lower gear and it has to absorb the horsepower during that brief moment . This is designed to keep the engine from "flaring-up" during that brief moment when there is no true connection to the wheels and the engine can run away to high RPMs . It usually is fairly small and not really up to the task under harsh conditions and it can whip the ATF into a mass of pink foam, letting it get out of the case . This is also more a FORD E4OD-E problem . . . as they have really puny overrun clutch packs and this is their biggest friction material weak link . Either way, if an AT is normally filled to a correct level and the leak is coming from a vent, they you are on the short end of the stick and are gonna be seeing a transmission overhaul expert soon . A less serious front or rear seal leak is easier to amend and it should not cost an arm and a leg to repair . Manual transmissions can take a severe overfill with glee . . . and these too have atmospheric vents that have to be looked at to ascertain if they are the culprit . If a manual transmission leaks otherwise, they likely do so out the input shaft/front seal (it is subject to wiggles and misalignment) or the rear seals . . it's more likely that the tailshaft/output seal, or the rear seal will fail earlier as it is subject to wiggles and misalignment more so than the front seal . A front seal leak will likely soak the friction material of the clutch if it does leak . You'll also need to replace the clutch if that happens . A rear seal leak will wet the tailshaft or the output housing of the transmission, making it obvious where the problem is . Many times when I rebuild a manual transmission, I like to overfill it a little while I have it on the bench and before it's installed . It just makes sure that everything gets sufficient lube for the first 25-50 miles or so . Overfilling an AT is OK for a short while . It should be corrected ASAP however, as foaming the oil makes it hard to control the hydraulic controls internally . It may also act strangely and act up as it tries to handle foamed oil . It will not usually harm the unit . . . but again that's if the level is corrected very soon . Another long tirade, sorry . . . . . but it's Sunday morning, my meeting isn't for a few more hours and I have the whole house still asleep and all to myself . I rather like sending this info off to NZ and wherever else it goes . . . . .	SurferJoe46 (51)
573846	2007-07-29 23:35:00	TY . . . Overfilling an engine USED to be (another old wive's tale here) the cause of blowing out the seals in an engine . The only possible scenario would be the anecdotal evidence of a large puddle under the engine after such mistreatment . As far as hydraulicking an engine by severe overfilling of the crankcase . . well, I guess it's possible if the oil actually got into the top of the cylinders and stopped the piston from coming to top-dead-center somehow . To actually hydraulic an engine means that a non-compressible fluid or solid (ask me about peanut husks someday) had to get into the combustion chamber keeping the piston from making it's appointed arrival . A bent rod, broken ring lands, cracked piston, brineled rod bearing surface or busted crank (not too likely nowadays) would be evidential . not that uncomman . a few people on a couple of forums i'm on have actually done it on deisels . also a few have a had the motor run on the engine oil . hydraulicking an engine by severe overfilling isn't that hard . if you filled it to the top of the filler hole, as Tut mentioned he had, (which is the top of the rocker cover) the oil would fill all adviable space inside the crankcase . if you managed to turn the motor over the piston traveling down the bore into the crankcase space would push the oil out of every possible space/seal . you can kiss good bye to the rods and crank fairly quickly . more of a reverse hydraulicking ;)	tweak'e (69)
573847	2007-07-30 00:51:00	So Surfer Joe, what do we have to ask you about peanut husks? I figure now is as good as someday... :D	Sick Puppy (6959)
573848	2007-07-30 02:35:00	So Surfer Joe, what do we have to ask you about peanut husks? I figure now is as good as someday . . . :D The first shop I worked in was in Anaheim, California where two brothers owned the shop equally . One was a dyed in the wool FORD man; the other a Cadillac man . Now, in the old days when there was a problem with non-detergent oils, which everybody THOUGHT they needed, there was also a lot of incidental ash formed on top of the pistons and that needed to be removed by "de-carbonizing" the engine on a regular schedule . The Cadillac guys always used peanut husks for this purpose, and they did that by slowly sprinkling some down the throat of the carburetor as the engine ran at high idle . The results were that the husks pinged around in the cylinders and chopped awaay at the carbon, throwing it all out the tailpipe . Dan, the Cadillac man told George, the FORD guy about it one time and George thought he'd give it a try and impress me and another mechanic with his smarts one day while Dan was out getting a haircut . George brought his own Lincoln into the shop, opened the air cleaner and as the engine ran he dumped some of the peanut husks into the carb just like he'd seen Dan do a few days before . After about ¼ of a handful of the husks had gone into the engine . . the engine shook mightily and instantly halted . Just in time for Dan to return, George tried the starter and the engine was locked solid . You see, Cadillacs had an open combustion chamber and the Lincolns/Fords has a squish chamber, The husks lodged on the top of the Lincoln pistons and broke ever one of them and cracked both of the heads . I never forgot that scene . . . George all blown away with a lunched engine and Dan just smiling as George pushed his Lincoln off the floor where he tore it down and had to buy a new long block . The moral: Don't assume anything . . especially things mechanical, romantic or sexual .	SurferJoe46 (51)
573849	2007-07-30 02:51:00	Last weekend I changed the oil in my 95 Mitsubishi Galant EXE . I noticed the oil was a reddish colour instead of black but no warning bells rang . The fact that the so called old engine oil was red instead of black should have raised warning bells . I wonder whar colour transmission fluid is:rolleyes: Thats right, its red . You emptied the wrong sump	plod (107)
573850	2007-07-30 03:00:00	if you managed to turn the motor over the piston traveling down the bore into the crankcase space would push the oil out of every possible space/seal . you can kiss good bye to the rods and crank fairly quickly . more of a reverse hydraulicking ;) Maybe! But remember that a piston going down also has its counterpart going up, so I don't see any volumetric change in the available oil to hydraulic the pistons or pressurize the crankcase . Now, trying to move a viscous fluid like lube oil from one under-cylinder to another and get out of the way of the crankshaft is a little more believable, but I don't see it causing any actual damage to the rods/pistons on the underside . As to the diesel running on lube oil . . yes that happens all the time on 2-cycle engines like Detroits . . . but even they are dinosaurs any more and not too available to screw up nowadays . For example, the Ford 6 . 9/7 . 3L permutations have a PCV device mounted low in back of the plenum chamber and they can cause a lot of trouble if the engine is severely overfilled with oil . I've gone on service calls where the dipstick has broken off and the driver just "guesses" that the engine needs oil and puts some in when he fuels up every time . That caused the crankcase to get so full, that oil was pouring through the PCV into the plenum and yes . . . the engine would not shut off . The oil build up so much gunk that a few valves stuck opened and the pistons hit them and then all hell broke loose . Engine time! The driver got fired . I made a lot of money and the fleet owner made sure that the dipsticks were intact from that point on . No . . IMO, I only actually see the problem if the oil gets to the top of the pistons, or in the case of the Detroits, into the intake ports in the sleeves of the cylinders . THAT would be messy . But again, that oil would have to travel through the supercharger first to get to the stuffed crankcase and then to the airbox and finally to the combustion chambers . I've had turbocharger seals fail and pump lube oil into the airbox and then the Detroit will run away on that oil . . . but that's kinda rare too . Back to the Mitsubishi: Maybe if the oil level was SO HIGH that it traveled thru the KV or CV system to the top of the cylinders, then YES . . indeed that too would be damaging . It has to get into combustion/squish areas to actually physically damage the pistons/rods I think .	SurferJoe46 (51)
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