Hey guys,
I have an engine with the following specs:
- 90.5 Mahle pistons with Total Seal third ring
- Engle W125
- 1:1.25 Rockers with swivel feet adjusters
- DRD L5 heads with stainless steel valves
- CSP crankcase breather box (big one)
- CSP valve covers with breather outlets
- 44 IDF
The problem occured is, that I discovered oil at the exhaust flange between head and header on cylinder 3. After disassembling and cleaning oil appeared there again and the engine had some blue smoke. Also the spark plugs looked quite oily. It was not exessivly blue smoke but recognizeable. It got worse over time until cylinder 3 didn't fire anymore - just sometimes while pulling the spark cable slowly away from the distributor.
So I disassembled the engine and found good looking pistons and cylinders with recognizable combustion residuals in the area of the piston to end of barrel (1.5mm). There is was recognizable that there must have been oil sitting at the bottom, since it was not oiled there. This doesn't give me too much pain.
Checking the cylinder heads, there is nothing super frightening but the valves and valve guides do look a little bit odd. I have some pictures here:
BTW the engine was until now not running more than 200km.
[IMGhttp://i31.photobucket.com/albums/c381/hatmax1/engine/D8FE7262-3A13-4E93-9BE1-91C1143A67CB_zps9mzwqqhb.jpg]http://[/img]
The valves have visual wear but are round and not criticaly below 8mm. The guides are not ellipsed - but a bit widened in the middle of the guide lenght: About 0,05mm maximum. Also when I'm pulling out the valves you can feel a edge at the end of the stem just before the spring retainer grooves start. I really have to pull the valve out with more force than usual
I contacted a guy being expert in rebuilding cylinder heads and with his equipment we measured that all the valves seal properly and that the guide is 8mm and not more. His opinion was that if he would replace the guides he would do them bigger than 8mm diameter.
What also caught my eye is that the oil ring seems not to be exactly stiff but measuring is about impossible. The first rings have a gap of 0,5mm to 0,55mm. The second (total seal) have about 0,55mm to 0,65mm and at one cylinders the gap of thick and thin second ring was at the same position.
Questions:
What do you think about the valves and guides? My impression is that the valves are of poor quality and that something might be wrong.
How can I check if the third ring is fine? Any problems known with the total seal ones?
Any problems known with the CSP breather boxes that they do not efficienly separate oil from air?
Thank you so much in advance! Any suggestions are appreciated!