TDI INTO PICK-UP

[Tez]

Why on earth would you want to go from gods fuel to heavy oil?

We like to go to the sea side almost every weekend, Its a three hundred mile round trip, takes a lot of petrol £££, Its a hard decision as the 2.1 motor that's in it is faultless, smooth as owt! but I dare not drive much more than 50 mph or it drinks juice, it'll do 80 no probs but 18 miles a gallon is no good to me (100 quids worth of juice to go the sea side) Anyway I've bought an engine and I'm now looking for a passat box to use then this winter after Vans at the Sands I'll take it off the road and do it. It'll be Ok!

[silverbullet]

Oh dear. Passat box = three words:

Pinion oil starvation.

[davegsm82]

Oh dear. Passat box = three words:

Pinion oil starvation.

This isn't what I want to hear.

How much oil should there be in there to stop the pinion going dry? I put about 4.5L in mine. Surely the crownwheel will pick up enough to stay well lubed?

Dave.

[silverbullet]

This is one of my pet hates.
There are good reasons why a transaxle is designed a certain way, not just because of the historical thinking behind the hypoid offset (a lower propshaft in front engine/rear drive layouts)
By turning a transaxle over and putting the pinion shaft and its bearings in the high position, they will run hot because of marginal lubrication: rear-engine diffs suffer because the crownwheel pulls oil away from the low pinion, whereas in a fwd it pushes oil toward it. This is why the SA diff oiling plate is neeeded, to encourage oil to stay on the crownwheel and carry round to the pinion head.
First and second gear synchromesh will perform the first shifts of the day almost dry and this will lead to premature wear etc etc
An upside down transaxle is not even an engineering solution to my eyes, its just a way of using a cheap plentiful transmission is a wholly inappropriate way.

[weimarbus]

LPG is the way to go, stay with the smooth engine and power, a diy kit from Tinley Tech will cost you much less than the engine and box change you propose, especially by the time you change all the nessesary service parts, eg timing belt ,clutch, oils, filters, water pump etc. Not to mention the reduced value and market of the converted vehicle.

[mrhutch]

9A with a cam puts you in the "driveable as a daily" ballpark

[davegsm82]

This is why the SA diff oiling plate is neeeded...

I'm not familiar with the SA Diff oiling plate, does this apply to the Passat/A4 box?

If I remember correctly from when I had the box in bits/on the bench, the fill level (overflow) plug is just under half of the way up the radius of the diff plate. In the standard configuration obviously this puts the input shaft well out of the oil bath, but as you suggest the syncros etc are all dry initially.

To be honest I've no idea what the oil level is like in the gearbox currently, 4.5L went in but I did lose a small amount from an improperly positioned vent hose.

Would there be any reason other than possibly excessive oil drag on the input shaft to overfill such that the pinion and bearings are constantly wet?

I have to admit that so far I've had no issues with the modification, initially I had some trouble selecting 1st for some reason but only occasionally. It's been absolutely fine for the last few weeks. Have done about 1000 miles so far.

Dave.

[silverbullet]

SA oiling plates are for VW 094 transmission. I mention them only to underline the inherent problems associated with rear-engined transaxles.

[davegsm82]

Gotcha, fair enough.

[Tez]

LPG is the way to go, stay with the smooth engine and power, a diy kit from Tinley Tech will cost you much less than the engine and box change you propose, especially by the time you change all the nessesary service parts, eg timing belt ,clutch, oils, filters, water pump etc. Not to mention the reduced value and market of the converted vehicle.

Ref the market value, I've had my pick up for sale for two years, perfect runner and never welded, not one person has been to look at it.