1.8Td Driveshafts In A Hdi Box

[Uberderv 6]

Hi all,

 

I am half way through fitting a HDI engine into my GRDT and would like to clear up what to do with the HDI box.

 

I know the shafts are the same as the 1.6gti and will fit but apparently they are slightly too long so something needs to be swapped between the xud and hdi box. I just don't know what that something is

 

The eventual plan is to swap to 1.9 shafts/hubs etc but for now I would like to get it running and mot'd etc .....

 

Thanks in advance for any help/links. Pete.

[Anthony 1,003]

I imagine that it's just a diff swap needed, much as you have to when using 205 shafts on something like a VTS gearbox.

[welshpug 1,666]

exactly that

[Uberderv 6]

Once the diff is swapped will it be ok for the 1.9 shafts too? Is it straight forward enough to change? any special tools required?

 

Thanks Pete.

[Anthony 1,003]

Yes, fine for 1.6 and 1.9 shafts (and 309 for that matter).

 

Easy enough to swap the diff over - a vice is handy but not essental for swapping the crownwheel across from the HDi diff onto the 205 one, but otherwise it's just normal tools and about 20 minutes start to finish if the box is already off the car.

[Uberderv 6]

Perfect thanks I will get started

[Uberderv 6]

What would be the result if I didn't swap the crown wheel over? I thought they would be the same part. I will be doing it this evening so fingers crossed I can get the box bolted the engine.

[omega 82]

did i miss the build thread on this?

any major proplems etc?

got a 406 hdi that i was going to scrap now having nasty thoughts but the mrs dos want the space back,

[pug_ham 245 3 Cars]

Hi Pete,

 

The standard 205 GTI diff is the same across both models (& they 309) but the 306 & later 405's use a different duiff that doesn't let the 205 driveshafts sit in far enough so they tend not to seal on the driveshaft oil seals very well & can also cause buinding problems on even slightly lowered cars.

 

What would be the result if I didn't swap the crown wheel over?

Not swapping the crownwheel over will quite possibbly wreck the box if the crownwheel teeth don't match perfectly it could chip one or lock the box while you drive.

 

For the sake of the eight bolts & half hours work it isn't worth the risk imo.

 

g

[Uberderv 6]

Cheers Graham will swap the crown wheel too

 

Omega, not done a project thread on here just on tdocuk.com , can post a link if you like? Probs at min are MC clearance, boost pipes and rear engine fork.

[omega 82]

Cheers Graham will swap the crown wheel too

 

Omega, not done a project thread on here just on tdocuk.com , can post a link if you like? Probs at min are MC clearance, boost pipes and rear engine fork.

 

link would be good as i havnt a clue what tdocuk is.

[Uberderv 6]

http://www.tdocuk.com/viewtopic.php?f=41&t=4991&hilit=uberderv+ii+project

 

I changed the diff over this evening, there is only a small difference between them in regards to the driveshaft position, fingers crossed that's all it needs.

The crown wheel on the HDI box has almost double the teeth than the XUD one, also every bolt in the HDI diff appeared to be cross threaded which was nice.

[pug_ham 245 3 Cars]

You might need to use the original XUD lower rear engine mount & intermediate driveshaft bearing housing so things are perfectly in line.

Hard to believe the diff / crownwheel bolts were cross threaded, maybe it was just lots of threadlock instead.

g

[Anthony 1,003]

Were they actually cross-threaded, or were the threads on the bolts just stripped?

 

According to Miles the later is very common, and certainly I've seen it before - 6 out of the 8 bolts on the last diff I removed the crownwheel on stripped, yet the threads on the diff itself were perfect and was fine with new bolts.

[welshpug 1,666]

had that when I swapped the diff for Dan recently

[Uberderv 6]

Graham I am sure the rear bearing housing will not fit as the bolt pattern is different. I think a simple chop,move and weld of the rear fork should do the trick.

 

Deffo no thread lock on there, every bolt had the thread stripped on the HDI box. Possibly not cross threaded and like Anthony has mentioned the diff appeared to be ok but I didn't rebuild it I just put in the 'spares' box

[welshpug 1,666]

bolt pattern on the hdi rear bracket is 3 bolt not 4, but the angle of the diff is the same if the box came from a 306, not sure on other vehicles.

 

shouldn't need to extend the fork, the XUD fits in there fine gives driveshaft issues if you do.

[Uberderv 6]

I don't need to extend the fork just move it over to the side by approx 10mm you can see a slight difference in the position in this pic-

 

Not the best pic but they are in slighly different positions.

[welshpug 1,666]

hmm, do the bolts line up? looks like just one missing, and the dowels slightly different.

[pug_ham 245 3 Cars]

Just a thought, what box are you using Pete?

 

You might need to re-drill the hdi crownwheel to fit the 205 diff or start changing the inner driveshafts ends to match the hdi box.

 

You are using the hdi box then it must something else because the box & engine mount should be a match from the factory so I incorrectly threw a curveball in & it won't be the lower mount imo.

 

g

[Uberderv 6]

The bolts do line up on the R/H edge of the XUD mount but as far as I remember the other one needs drilling.

 

The box is out of a 306 HDI. The diff when fitted to the XUD crown wheel sits on the R/H face of it so bolts in from the left. It's the opposite for the HDI diff but it does go together as it should if you get what I mean?

[welshpug 1,666]

yup

[Uberderv 6]

Just to update this a little bit, the engine went straight in using the original mounts. The sub frame has two mounting points for the rear fork so using the one closest to the d/s hub it lines up perfectly.

 

Problems now are M/C clearance and boost pipes.

[Uberderv 6]

New problem now Changed the diff, swapped over the bracket for the gear selector rods and when its all connected back up I can't get 5th or reverse.

I have looked underneath and there is nothing obstructing the rods... Could it be that the rods need extending to get the HDI box to work properly?

 

Cheers Pete.

[Anthony 1,003]

Did you change the selector arm and accidentally allow the selector shaft to drop? Causes exactly that issue...