S2 Avant -93

[Kiku]

I always use green loctite. Never had a leaking plug even with very corroded sockets.
If possible then installation(hammering) is done with engine block tilted horizontally in stand.

[Crasher]

The FEBI plugs are perfect, use thread lock to seal them and don’t apply pressure to the dish, just the edge. I have fitted thousands of FEBI core plugs and never had one leak.

[Antsa]

Friday I received everything I needed to pressure test the coolant system for leaks. I fitted the water manifold and used silicone caps to block all outlets. When torquing the water manifold bolts I found three of the threads were stripped and they couldn't take the required 10nm torque. So I repaired them using helicoils. After filling the system with coolant I found that one of the water manifold outlets on the cylinder head is leaking. Upon closer inspection it seems that whoever made the holes for the water manifold (I have a modified 7A head) did not do a very good job. There is a deep scratch in the head where the water manifold o-ring should seal. Nothing a little bit of rtv won't fix Now I have left the rtv to cure before attempting the pressure test again.

[Antsa]

Leak test now done. Water manifold is going to need to be sealed with rtv and the rear block coolant outlet needed a new o ring. After that I filled the block and head with coolant and pressurized the system to 1.4 bar using compressed air through the turbo coolant feed. All good now

Tomorrow I will give the first set of aluminum parts a ceramic coating. I ordered a bottle of cerakote clear ceramic coating meant for aluminum parts.

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[Antsa]

All aluminum parts were coated today. First they all got a clean in hot water plus dish soap, dried with compressed air and then I sprayed on the coating with a small spraygun. The stuff goes on pretty thin and that the half litre bottle I got was an overkill, I used maximum of 100ml of it.


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[Crasher]

I went down the aqua blast and clear powder coat route with the exhaust manifold and turbo turbine housing done by Camcoat.

[Tom_]

how much cost that cerakote bottle? Parts looks nice

[Antsa]

I went down the aqua blast and clear powder coat route with the exhaust manifold and turbo turbine housing done by Camcoat.

Nice looking parts I was also looking for passivation treatments, but that would mean I should post the parts to be treated and the companies that do them generally like to do bigger batches at once.

[Antsa]

how much cost that cerakote bottle? Parts looks nice

It was 80euros for the 473ml bottle.

[Antsa]

I've been goin back and forth about balancing the pistons and connecting rods myself. I didn't have a precision scale or balancing fixture for weighing the rod big and small end separately. Turns out that scales capable of 0.1gram accuracy are not that expensive and a balancing jig can be 3D printed. So my friend is going to print me one

While waiting for the jig to be finished I started with the pistons.


All pistons were numbered, put on the scale and the weight was noted.

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This is the lightest one which all the other pistons will me matched to


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This is the spot were I removed material. Taking away 2 grams from aluminum piston is a little terrifying for someone putting an engine together for the first time.


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[Antsa]

Connecting rod weighing fixture was printed and put together. It works very well given that it probably cost a little over 10 euros in material. All the rods big and small ends were withing 0,5 gram, so there was no need grind anything Hopefully next week I can take the crank for balancing.


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[Crasher]

I had Camcoat treat the pistons, Ceramic on the crown, anti friction on the skirts and oil shedding inside. Probably makes no difference but looks nice... and I know it's in there; rather like when I build model tanks and aircraft with full interiors (but no humans ) but once built, you can't see them.



I had the rods and crank Black Nitrided, AKA Tuftriding