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.

20260511_094054.jpg




20260511_094105.jpg

[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.


20260513_144713.jpg



20260513_144701.jpg

[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.

20260517_175846.jpg


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


20260517_175849.jpg



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.


20260517_175915.jpg

[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 within 0,5 grams, so there was no need grind anything Hopefully next week I can take the crank for balancing.


Tellinki.png

[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

[Antsa]

Another quiet period has passed, but I have the crankshaft back from balancing and today was time to check and adjust the piston ring end gaps. I bought this manual ring gap filer for the job.



20260717_181544.jpg


I used a piston to set the ring in the bore and then measured with feeler gauge. I set the top ring at 0.4mm and bottom ring at 0.45mm gap, sligthly larger than the engine manual says.


20260717_181604.jpg


20260717_181817.jpg


I still have the cylinder head with nothing done to it, so I called a cylinder head specialist. We agreed that I will post the head over and after checking what condition its in, we'll figure out what to do with it.

My bonnet also had these weird lines around the washer jet holes. They have been bothering me a long time and I decided I can't leave them. So I took the orbital sander to it and will paint it again

20260717_104927.jpg


20260717_131134.jpg

[struikie]

Wouldn't Nordic Porting Services have been a good place to send your cilinder head to?

JW

[Antsa]

NPS was one option, but I think I'm going to send the head to Kansiset.