Changing Gearbox Oil on a VR6

[G-Lad 0]

What's the correct volume of oil for a VR6 gearbox? I was under the impression it was 2 litres :scratch:

 

I've just drained and refilled mine (draining from the bottom plug, and refilling from the forward facing 17mm plug) and only 1.5litres went in before it started spilling out of the front.

 

[ATTACH=CONFIG]51180[/ATTACH]

 

This guide (below) says to run the gearbox in second gear for a couple of minutes, but I can't see how this guy got a full 2 litres / 2 quarts in the gearbox, without it spilling out everywhere!

 

http://www.corrado-club.ca/mods/tranny_fluid_change.html

 

I can't believe the Canadians have a different spec gearbox in their VR6s but hey, maybe they do!!

 

I'm going to run the gearbox for a couple of mins as suggested, to see if any of the 1.5l gets displaced inside and lets me squeeze the last 500mls in, but I don't see it happening!

 

...I'd love to know the official gearbox oil volume from a textbook / experienced person please :bonk:

 

Cheers folks

 

 

Chris

Edited January 21, 2012 by G-Lad
added pic

[CazzaVR 0]

Pretty sure it's 2 litres/quarts as you say. I've always managed to just about empty the two bottles. There will always be a little oil left in, but wouldn't think 1/2 a litre. Did you drive the car first to get the oil warm? This is a must. Also, how long did you leave it to drain for?

[RW1 0]

Its 2.0 litres (VW workshop manual) for all gearbox codes with the gearbox level, not a jacked up car. If you jack up and try to put more in, you risk it blowing the shaft seals or it will weep past anyway, cos its too full.

Being wet, it works out at about 1.90 ltrs that is put back in.

 

Best way to drain a gearbox is with the oil warm to hot (ie. 30 mins running time). It flows faster and therefore drags debris out better. Plus there is less left clinging to internal gears and shafts.

 

Leave until the drips are down to one every 2 seconds. Call it a day at that point.

 

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Edited January 21, 2012 by RW1

[G-Lad 0]

thanks for the reassurance :)

 

OK, so perhaps it didn't help that I didn't warm it up sufficiently before draining (car is SORN, so doing a fluid service after 9mths standing), though it did drain for 45-60mins with both drain and fill plugs out, and only looked like approx 1.5l of oil in the old washing up bowl i use (handy volume marks up the side). After I threw in 1l of unused but oldish fuchs hypoid gear oil (from my golf, oil bought about 4 years ago) to flush out any grud, that brought the volume in the bowl up to about 2.5l, suggesting the whole 1litre of clean flush oil came through.

 

I started with 3 x 1 quart bottles of MT-90 (bought 1 extra for fear of running out by 100mls) and have weighed one empty bottle, 1 full bottle and the part full bottle. After taking away the weight of the empty plastic bottle (90g) I've got 405ml left in the second bottle. That means I've got 946ml + 541ml = 1487ml of MT-90 in the gearbox (give or take probably 20mls that spilled out before I stuck my finger in the funnel)....

 

Very odd!

 

I guess if the rear of the car is on the deck and the front is jacked maybe 12-18 inches, and the oil is flowing out of the fill hole, then if anything it is slightly over filled, not underfilled.

 

It sounds like the worst case is that I've mixed dirty old oil with old but clean fuchs oil, and about 1.5l of MT-90. Agreed? Potentially a bit of a waste of the MT-90 :(

 

I guess I can do the same trick after I've retaxed, MOTed etc and gone for a drive - that should increase the relative volume of MT-90 at least, though if 2 litres is correct, I'm now about 500mls short of a full warm gearbox oil change...

:bonk:

 

---------- Post added at 03:28 PM ---------- Previous post was at 03:23 PM ----------

 

If you jack up and try to put more in, you risk it blowing the shaft seals or it will weep past anyway, cos its too full.

 

Yes, I've done that before on the Mk2 16v, hence my paranoia. Had to have the output cup oil seals replaced - good to note though. Over filling is just as bad as underfilling.

[RW1 0]

1 quart = 2 pints = 1.14 litrs.

Therefore 1 full & about 2/3rds from a second quart bottle.

 

There are no pockets inside that store gear oil.

 

But you can create one if the Corrado is jacked up cos it puts the drian hole near the higher point and that would cause oil to stored in the bottom of the gearbox towards the engine end. Have you done that by accident???

 

I empty/fill (all VW boxes) with wheels on level ground, no jacking.

 

.

Edited January 21, 2012 by RW1

[G-Lad 0]

The bottle of MT-90 states it holds "1 US Quart / 0.946 liters" so I think my maths is close enough.

 

I've been underneath again and considering the very slight slope in my garage which points the nose of the car down hill (so slight a slope that it's safe to jack from) and considering that the jack is as low as I can keep it, while physically being able to squeeze small belly under the car, I think the angle is probably not a big enough factor to be causing the drain hole to be too high and cause a significant pocket (or at least I hope not) - thanks for the suggestion though :)

 

Now the oil is in, albeit mixed a little, I think I'll move the car to billiard-table-flat ground and whip out the fill plug (now lubed and smooth) to allow the excess to drain, before I go for the MOT and to ensure I don't blow a gearbox oil seal...

 

...now to wrestle off the bottom rad hose and do the coolant! wish me luck :D

[RW1 0]

Good point. I'm too old and remember Imperial Quarts & Guineas :lol:

 

It will always be mixed a little as you won't get it out of the shaft bearings. A second fill may give you better but it still won't be perfect.

 

Is this the VR6? If so, warm the engine to open the thermostat.

 

Why the rad hose????? There is a little drain plug on the cross pipe just behind and slightly to the left (inboard) of the alternator. You can see it with a torch on the underside of the cross pipe. The stopper with knurled edge is about the size of a 10p coin and its thickness visible is about the same as a 10p coin.

 

Watch you hand when finally removing the last turn of the stopper and it starts to drain. The engine core coolant will be at operating temp. I usually leave mine a couple hours to allow the core to cool a little but the thermostat is still open a little.

 

If the thermostat is open, all the coolant will come out. If its closed, you only get out 3/4trs. (Same would apply if you went the rad hose way method and it would be less I think.)

 

.

Edited January 21, 2012 by RW1

[Yandards 0]

Easiest way to fill the gearbox oil is get a 1m (or about 3 feet) of 30mm bore oil hose, I then feed that down through the engine bay and into the gearbox filler hole, you can then lower the car back onto level ground and fill up with ease.

[G-Lad 0]

Is this the VR6? If so, warm the engine to open the thermostat.

 

Why the rad hose????? There is a little drain plug on the cross pipe just behind and slightly to the left (inboard) of the alternator. You can see it with a torch on the underside of the cross pipe. The stopper with knurled edge is about the size of a 10p coin and its thickness visible is about the same as a 10p coin.

 

Doh! Yes it is the VR6.

 

I thought I had read about a stopper elsewhere but couldn't see it, and spurred on by this thread (http://the-corrado.net/showthread.php?46198-VR6-Coolant-Flush) I just whipped the hose off...

 

As predicted, that got me about 4litres of coolant out, into a bucket. I've already read up on the proportions i need for refilling, so I'm expecting to see 9-9.5litres! Knowing something was up, I tried pulling out one of the thermostat temp senders, but no joy (presumably the wrong side of the 'stat).

 

With only 6ish litres of coolant in the block, can I now start the engine up to heat the thermostat and release the remaining coolant?

 

What happens when the new cold coolant goes in after the thermostat has cooled? Do I have to part fill the first 4 litres ito the rad part of the circuit, and then run it before the remaining 5-5.5 litres will go in? Doesn't that leave the block empty when I'm first running it and at serious risk, or is the oil alone sufficient to keep it cool during the refill process and thermostat warming / opening stage of the task?

 

Aye curamba, I feel like a right newbie today!!

 

Thanks for all of the help.

 

Chris

[RW1 0]

Just put the hose back on, plug the sender in and top up with plain water (you ain't working at sub zero artic temps (well, not yet)). Then run it to open up the thermostat to get the amount you mention as expected.

 

When filled statically, you will have to run it again to open the thermostat, run initially with the header tank cap off and continue topping up. Seem to remember putting in half a header tank full last September, ie. the whole of the bottom half after putting on the header tank cap. Fill to the halfway as final level when warm. Down 5 to 7mm from midway when cold.

 

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Edited January 21, 2012 by RW1

[G-Lad 0]

thanks, will do :)