[project] Project 205 Xu13j4

[B1ack_Mi16 67]

Thought about it, as it looks as there is a slight amount of pitting between the cylinders too from the old head gasket I might at least take it to a machineshop and ask what they think.

 

And I finally think I need to invest in a proper straight edge / flat bar so one can do some kind of examination oneself.

[Tom Fenton 1,541]

I'd also use that head as it is. If there is any material really proud, knock it off flat with a needle file first.

[Andy 105 1 Cars]

I do not have the experience or either Tom or Peter, so tend to be a bit paranoid about head surface finish. Looking at the photographs of your head, I would be taking the above two bits of advice and bolting the head back on with a nice new gasket and some new, well lubricated bolts .

[petert 586]

When I use a copper gasket, I rely on the mechanical o-ring for combustion sealing, however for oil & water, I smear 1211 on both sides of the gasket. End of story.

[SRDT 175]

I used loctite 5923 with great success.

A 50 years old tractor cylinder head had a big casting defect so the new head gasket just couldn't seal. It was leaking like a sieve until a liberal amount of this ugly paste was applied.

[B1ack_Mi16 67]

Head is in for a slight skim.

 

Today the headgasket arrived and I was really keen about that.

 

 

 

It looks ace and have stopper rings around the bores:

 

So looks pretty good.

 

After trial fitting it however it proved just to be wrong

 

The bore is 88mm and not 89mm as I ordered and drew in the DXF file... 

 

I'm not sure how the model was altered, but at least it has also affected the bore spacing and bolt spacing pattern... so the bore furthest away from the centering dowel is about 1mm off-senter too...

So now I just need to wait for a response on my complaint and see what happen next... very frustrating.

 

[Andy 105 1 Cars]

That is frustrating .Given that the block is an Xu10 , it is very surprising that the bolt pattern and bore spacing are in error , but a real nuisance for you  as it delays you . Is the gasket directly from Cometic ?

[B1ack_Mi16 67]

No it is not from Cometic at all, didn't get any response from them regarding custom gasket, but I am wondering if I'll have to try to get in touch with them again.

They seemed to respond much better 10 years ago on inqueries compared to today...

[Andy 105 1 Cars]

Ah.Hope you get some positive response from the gasket maker .

[B1ack_Mi16 67]

So finally the re-done gasket came as a early X-mas gift.

 

[Andy 105 1 Cars]

Excellent. So there is a Santa Claus after all. Hope it all fits together well and behaves itself subsequently 

[B1ack_Mi16 67]

I've also assembled the head after the skim and set the valve clearances while waiting for the gasket.. so maybe some assembly progress soon to come now

Valves were given a slight regrind and valve seal was confirmed.

 

 

 

 

Edited December 23, 2019 by B1ack_Mi16

[petert 586]

Hopefully the gaps won't close up like mine did recently.

[B1ack_Mi16 67]

Hopefully not.. I'll try to measure CL again once head is on... might the head distort a slight bit more if using a copper HG if there's o-rings around the bores, resulting in more uneven gasket pressure?

[Andy 105 1 Cars]

Based on my vast and extensive experience of one solid lifter head, I got the clearances absolutely spot on on the bench, installed the head and , almost as an afterthought, checked the clearances. Yep. Not one was where I had left it . Had to start again. 

[B1ack_Mi16 67]

Yes  I suppose I will measure the clearances after the head is on again.

Just been tidying a bit in the garage tonight preparing/gathering motivation for putting head back on.

 

Had the thermostat housing slightly modified, welded in aluminium pipe instead of the orginal steel one that had started to rust quite badly.

Also removed the 10mm pipe take-off with the bleed screw on, and replaced with self made bleed screw attachment.

 

 

Also concidering to buy new injectors for it as the ones I have on are of the rather old style, was brand new back in the days, but I believe some proper new style ones will atomize the fuel significantly better. So made some injector spacers on the lathe lately as the new one usually are a tad shorter than the old ones.

 

 

 

[petert 586]

Can you fit an 8V housing on a 16V head? I never knew that. Are the extenders made of stainless? Good turning exercise but they're also cheap to buy:

https://www.efihardware.com/products/2937/Injector-Height-Adapter-1-2-Height-to-3-4-Height-11mm-Oring

 

Edited December 30, 2019 by petert

[B1ack_Mi16 67]

The housing fits fine, missing one bolt I think, but only on the upper part which ain't problematic anyway regarding oil leaks as the oil seal is in place on the camshaft.

Just using it as it is a nice bracket for the coilpack.

 

Yes I know the adapters can be bought. Found some in the correct length made for Audi, but the locking clip groove was not in the right spot. As I just bought some tools for the lathe it was nice enough to do some self learing, it is aluminium btw.

[B1ack_Mi16 67]

After I got my straight edge some days ago I found out that the block actually had a slight high spot in the middle, nothing major but about 0.03mm.

 

As I really can't be arsed to spend time on dismantling and getting it machined I decided to try to sand it flat myself.

 

So I set out to look for as flat as possible piece of plate that I could find. Then I took a piece of wood and sanded one side completely flat (as flat as I could at least using my workbench which is 4mm steel plate bent down 90 degrees at the front, making it quite rigid).

 

Made the tool:
 

 

Started sanding it, first with 120 grit, renewed paper (which I glued on) 3 times.

Then I took a last pass with 240 grit. Wet sanding with WD40 all the time.

 

It turned out surprisingly flat and nice.

 

 

 

Checked with the straight edge and my thinnest feeler gauge of 0.02mm in all directions and around the whole area it is impossible to get the feeler gauge in.

 

 

Only place there is a slight low spot is at the gearbox side oil drain at the outer edge, I can't get the 0.02mm feeler gauge in there anymore, but I guess it probably is between 0.01 and 0.015mm at the edge. This however must have been much worse before, so I am not afraid of that.

 

You can see slight contours of the sealing area of the old head gasket at the remaining low spot.

'

 

Never thought it would be so "easy" to resurface the block.

 

[petert 586]

Nice work!

 

I see a knock sensor. Do you use it?

[Romb 0]

Wow, super cool project !

[Andy 105 1 Cars]

Full marks for bravery, determination and ingenuity. How did you manage to contain the sanding debris to avoid it getting into oil and waterways and down into the top piston ring groove ?. 

[B1ack_Mi16 67]

The knock sensor is just wired to a mini-jack outlet I have in the dash area. I had it connected to a small amplifier and head-set once when dynoing it. Not connected to the ECU.

 

I didn't care too much about the oil returns and waterways to be honest might fill the sump with some thinner or something and drain it before I fill oil.

Stuffed sylinders with paper and cleaned often during sanding.

 

Oil feed I did push pipe-cleaners into and then filled the top with grease, havent pulled it out yet but the grease didnt seem to let anything in

[Andy 105 1 Cars]

Deeply impressed.

[B1ack_Mi16 67]

So got some new parts and I've been struggling for a long time finding new top mounts for the front, as I'm putting on 306 Bilstein B6 dampers and Eibach springs on the front so it will be easy enough to get it through MOT, which it ain't with the coilovers.

 

I had to cut off the location dowel from the new Partner top mounts, and drill 2 new holes in them.

My chassi legs where the struts locate already had a bit "widened" holes for the bolt pattern of the eccentric mounts I used with the coilovers, but I had to slightly open it up a little bit more actually to fit these new.

 

Another finding is that the new mounts seem to be approximately 10mm shorter than the orginal ones, so the car will probably sit 10mm lower than with orginal type top mounts.