ThePogs Fiat X1/9 - Deep in the box

[ThePog]

That first box looked pretty good.

 

But I ended up breaking a bit of the casing in my efforts to get the seriously rusty bit of clutch shaft out. You can probably spot the bit in this pic, it probably would be ok but still.

 

So I decided to use the other casing which was a lot cleaner anyway, but this meant dismantling the second box. This was kindof good as it gave me context to decide that the first box was indeed a goodun.

 

The second one was still pretty good, but it had the keyed shaft that was broken on the one in the car (altho not broken) but the nice box is obviously a later revision as it had a spline rather than a keyway.

So I dragged my parts washer out from the depths of the container and cleaned/dried off/inspected everything.

 

Now I just need to find some axle seals and it can go back together.

Oh and sort the diff as well, but if I use the good box diff I will need to fix the endfloat situation, probably.

[ThePog]

Had a spare minute so I thought I would have a hack at a fuel return/restrictor.

Found some brass hex, put some detail into it including a 1.5mm hole and some probably correctly tapped holes, surely BSP and NPT are the same?

 

I checked the resulting pressure but the needle wobbles all over the place from the pulsing of the pump, averaged out it looks like 3.5 or 4 psi, vs 4.5 to 5psi previously.

Ill take it for a spin later and see what the AFR's are doing, then maybe start opening up that hole. I kindof need a way to damp the pressure fluctuations first to get an accurate reading.

[ThePog]

I probably forgot to say I am doing this because the idle circuit (that controls up to about 3000rpm) is running pretty rich, ie about 10 or 11 to 1. I spoke to Murray...? at Weber Specialties who was prepared to talk about Fiats in general and X1/9's in particular for a looong time.

I wanted to source some smaller idle jets but he said that the 45's in it were as low as I should go and that the 5psi the pump was putting out should really be cut down to 2.5psi for the DCNF's.

The return line wasnt connected so I reasoned that a restricted return should lower the pressure appropriately.

I guess we will see.

[ThePog]

Pulled the drivetrain out tonight and pulled the sump off to take a look.

 

I hope my engine stand won't buckle under the strain lols

I can't see any wrong in there, the sump is 100% perfectly clear of debris. And everything looks great, no missing chunks of piston or the like.

There is however a noticable variation in turning resistance with the plugs out, I am suspecting a slightly bent valve or broken valve spring.

I am waiting for a new head gasket and bolts before I get too carried away.

 

 

Also: so many gearboxes, this isnt even all of them, I have 2 more.

 

[ThePog]

Opened things up a bit more, tbh it looks pretty good. Altho number 2 is slightly browner than the rest in the head.

The cam spins nice and free so its not that, but the with the head off rotating the crank is still ever so slight weirdly variable in turning force. The bores look basically perfect so maybe that means the crank might be bent? Rings broken?Time will tell I guess.

 

[ThePog]

Bottom end is mint, bearings are perfect still and without the pistons in the crank spins freely.

Ill take the head to Mean Machine tomorrow to get it looked over, see what they have to say.

 

[ThePog]

Engine shop mans keen eye pointed this out

On the lighter coloured cylinder too, so could well just be the head gasket.

They are going to check it and give it a skim.

There is a certain amount of scum that forms in the header tank, not much so I thought it was just clag from its long park up getting blown out, but maybe not..

[ThePog]

So I have been attempting to get the box back together, but it has taken 3 attempts so far;

#1 - all the clusters back together, everything inserted and getting to put 5th gear on when I realised I was so intently following the written writup on Xweb that I had forgotten to put the actual gearshifting mech in because it wasnt part of the writup. Sigh, gently pull it apart and scrape off all the blue gasket poo.

#2 - everything back together again but realising the there was some burring in one of the the detent ball holes and the now impossible to get out ball bearing was moving neither forwards nor backwards. Sigh, gently pull it apart, extract the ball and then scrape off all the blue gasket poo.

#3 - slowly and methodically reassemble it all again, barely even referring to the writup cos there is now an element of familiarity with the process.

I am still waiting for some axle seals, but apart from that its all done.

Like the old box it has a tapered drain plug in a straight tapped hole, I think I will make a straight plug up so I dont split the case.

Anyway there are very few pics of all this as it required much concentration.