1.9 1y engine gearbox confusion..

[nikalele]

Hi there, Im new to the scene and in need of advise.
I have a 1.9 1y engined t25 4speed. bought it a couple of days ago. had a long journey home after buying it all motorway miles from preston to cardiff. everything was great although i did find that when in 4th i could only potter along at about 50ish (although speedo doesnt work so thats a guess, it felt slow) otherwise it would be revving its breasticles off. there seems to be enough power to make me want to shift up another gear. Also 1st seems pointless even being there as you have to change into 2nd pretty much stright away after fighting it into 1st ha. Just wondering if anyone agrees or knows of a better gearbox to give a more enjoyable and economic cruising speed?

Thanks,

[Aidan]

chances are your van was originally a 1.6 or 1.7 na diesel with gearing to suit
you need to find the gearbox code on the box you have fitted to see what you have but probably fitting a TD gearbox, ie 3H would be a help, or even a petrol box like an AAP, but everyone wants these, many are shagged, and prices are high
all five speeds have a real low first gear great for getting a towed load moving or for really steep hill starts but otherwise pretty useless, but do use, constant pulling away from static in second will shag the second gear synchro

[nikalele]

thanks for the reply,
I cant find the code... not intirely sure where about on the box it is. Also iv looked into the 3H box and iv noticed its a 5speed. would this cause and problems if i was to swap the 4speed i have for a 5speed? im a bit of a novice...

cheers

[nikalele]

hey,

after nearly half an hour of scraping away grime and spitting on my gear box iv found the code hah. Its ABF box. now iv looked at the tables and found my box.. although the numbers mean nothing i dont really understand the ratios or final drive or anything to do with how they work tbh so then, what to do now?

[Aidan]

ok
ABF is a very low geared 4 speed box fitted to load lugging na 1.6 diesel vans (bigger the number lower the gear)
To stay 4 speed and get the longer legs you could try the ABD petrol gearbox which is real common fitted to the 1.9 petrol vans, change the bellhousing and input shafts over and you'd have more of a cruiser and a useable first gear and is broadly comparable to the 3H but without the extra gear in the middle and real low first. Since you don't have a turbo to worry about this should be an acceptable compromise/upgrade

[nikalele]

ah i see.
Okay, how is it the the ratios for ABF and ABD are the same for 1st 2nd 3rd and 4th yet the final drive ratio is different? what exactly is final drive?
Sorry to ask such a broad question... need to understand this theory behind gearing i think before i start faffing around with it... If its complicated dont worry about il get on the old wikipedia and have a browse.

[Plasticman]

http://www.brick-yard.co.uk/VehicleSpec ... fo/gbx.htm" onclick="window.open(this.href);return false;
Hope this helps a bit,
mike

[psychonaut]

Aidan - how would you get around the problem of the starter motor being in a different position on a petrol gearbox to a diesel one? Apologies if that's a dull question and there's an easy fix!!

[Aidan]

final drive is the ratio of the crown and pinion set, ie the shaft that turns the differential
6tooth pinion shaft 29 teeth on the crown wheel(on the diff) =4.83 final drive
your slow diesel is 6 tooth shaft with 35 tooth crown wheel =5.83

no before you ask you can't just swap the diff over the crown and pinion set are just that a matched pair that were ground together so they are perfectly matched and the tooth patterns are specific to the ratio so a 6 tooth 4.83 is a different cut to a 6 tooth 5.83

but otherwise internally the petrol and diesel boxes are the same, often with the same gears and same differential
2.1 gearboxes have a four pinion differential that's the difference between a 2.1 and 1.9 oh and the bellhousing has the extra reinforcement around one of the holes for the accelerator cable stop to be fixed to, but that's not real important

re the petrol diesel box swap you have to change the bellhousing and the input shaft over - the diesel bellhousing obviously matches the bolt pattern on the engine and covers the clutch and the input shafts are specific because of the effective length of the clutch/flywheel etc...the diesel shaft is shorter - swapping the bellhousing and input shaft should be on the wiki; please note it is important to fit the input shaft properly, many are not fitted right in my experience and this can lead to the mainshaft being pushed into the box which eventually will cause big problems, including mainshaft bearing failure which will likely mean a £1k bill for a rebuild. If you are doing this read the section in the gearbox chapter in Bentley which explains exactly how to do it - top tip is screw the threaded joiner fully into the mainshaft before offering the input shaft up and screwing it on, screw it on fully then back off 3/4 spline to the point where splines are alligned and sleeve will slide down and mate the two. There should be movement at the end of the input shaft upto 1cm sometimes when worn, but this end is fully supported by the spigot bearing in the end of the flywheel - remember if fitting a 1.9 diesel to fit a spigot bearing there won't have been one in it when it was in the car cos they have a diferent gearbox with a fully supported input shaft - I have seen dozens of cases where this wasn't done, result worn input seal gearbox oil in the bellhousing ruined clutch and knackered oil thrower and bellhousing, huge work and cost for the sake of a £6 bearing not being fitted by a numpty



gearbox ratios were many because there are so many body types and work/life expectancy for vehicles, so you would order something low geared for a na diesel that was going to be a tow vehicle say and a fast people mover caravelle would have had a higher geared box.

Many campers are converted work vans so may not be ideally geared for their new life, or peoples expectations now they drive modern point and squirt cars, and when boxes go bang they are often replaced with the first cheap compatible box that comes along. The n/a diesels tend to die early and be scrapped so their boxes end up in the 2nd hand system - for me they are good, often very nice inside, but with a final drive ratio that no one wants so they get stripped for the gears and shafts and case parts, so when your nice ratio box needs fixing I have parts to fix it, but if the crown and pinion is shagged then you'll be facing a big bill for a new one while they are still available from germany and when they are gone the bill will be massive as the remanufactured ones are twice to four times the cost, which is why I always say change the oil regularly

[camper]

Aidan sorry to hijack this thread.Can you tell me if you may be reconditioning DK code gearboxes .I spoke to you some time ago and you said its a matter of getting enough interest .

[Aidan]

sorry too busy with the watercooled stuff and not enough interest, try Bears Motorsports in brum, they have a good reputation, have a website with all the info

[nikalele]

Okay,

so i get the theory behind how it works, thanks aidan seems pretty simple really once you get your head around it. some useful videos of youtube helped a bit too.
You say that you need to change the input shafts over... once the gearbox is off and bellhousing removed is it an easy enough swap? how do you get it out? all i can seem to find is that theres a circlip that needs to be romved and then the input shaft comes out. surely is cant just slide out? or is it that simple i have no idea.
Whats the best way of getting the gearbox out? iv found the section in the wiki with the homemade gearbox removal board thing. but i cant find anything on how to actually change input shaft.
Am i right in thinking to change the gearbox over you need to:
First obviously jack the back end up and chock the front,
Drain the box,
Remove linkages to it (shifter, clutch, then drive shifts and anything else i can see connected to it remembering where they go. bag them up and move out the way)
get the box supported using maybe the board technique (or anyother suggestions)
unbolt the gearbox mount the the far end,
unbolt the bellousing from the engine,
drop the box out,
take off the clutch plates
remove the bellhousing from the diesel box and put it to one side,
remove the circlip retaining the input shaft,
...do the same for the petrol box...
take the input shaft from the diesel box and put it into the petrol box,
reattach the diesel bellhousing to the petrol box (is it just a straight swap?)
put the clutch bits back on in the order i removed them,
fit spigot bearing to flywheel?
get the petrol box with diesel bits all fitted back onto the board and jack up ready to slot back in place,
wiggle it on carefully,
bolt it all back up nice and tight (im guessing theres specific torque requirements when putting them back together)
reattach driveshafts,
reattach gearshift linkage and clutch pedal,
fill box with transmission fluid (what type is best?)
let the back end down,
Start it up,
take it for a spin,
come back,
fire up the hob,
make bacon sandwich and cuppa,
job done.
simple

haha if this is pretty much it i may give it a go. im guessing there are probably some gaskets to renew alongthe way. between the bellousing and gearbox? gearbox and engine? no idea. anyspecial tools i may require?

looking at the numbers in the table im guessing that most 4speed 1.9 petrol boxes would fit and give me a better drive? final drive and other gear ratios look the same as the ABE box you suggested, is this true?

Lots of guessing going on here. please add any addition to the list

Cheers

[Aidan]

looks about right
gasket for the bellhousing about £3 new from VW, often possible to reuse with a smear of hylomar if it comes off intact
I'd recommend changing the input seal too as it's easier to do with the bellhousing off, Brickwerks is cheapest source for these
ABD box I suggested, ABE has a lsd and not very common

[nikalele]

Nice one, thanks a lot for your help man. should keep me busy! have you tried making one of thoese gearbox boards? is it literally bolted onto the jack and then bodged brackets going round the board and attaching to the box?

As for torque settings? are these vital to get right or can i just tighten them up as tight as i can get em?

So i was right in thinkign the input shaft jsut slides out after the retaining circlip is removed?

[Aidan]

the gearbox board is my design copied by hacksaw bob, it uses an old upper ball joint as the pivot/attachment to the jack so the box can move in all planes for allignment but retains it on the jack so it can't fall off, makes it safer for one man job, a syncro gearbox is 65kg and they hurt you when they fall on you, even the 4 speed is nearly 40 kg
There is a sleeve that is retained by the circlip, you pull that back and then unscrew the input shaft, it will all become obvious when you are doing it
18ft lb, ie 13mm spanner tight only if you strip the case threads you will have to helicoil or timesert as the box will leak otherwise but there is usually corrosion under the bolts so a bit of crumbling is to be expected, just be careful,
enjoy