Holden V6 3.8litre 2001 8928km Delo 400 High Si !

[vxcalais]

Had my gaskets changed over recently due to cracked valve springs, valve sealing chamber causing gasket to blow out. These works were done nearly 9000km before test. 1 litre of top up oil was used. Recent test are the first results and the second set are the last test i did. The silicon is very high. Lead and Iron are also high. Cast iron block and heads, aloy intake. New gaskets installed, sealant only used on portions of intake manifold gasket as per GM instructions. Where would the Lead be coming from ? Recoed heads also installed etc.

282928km (Delo400) 219665km(Synpower 10w50)
PQ 31 3
Fe 82 12
Cu 43 23
Cr 9 1
Pb 21 2
Sn 4 1
Ni 2 0
Al 10 2
Si 79 20
Na 20 4
K 7 9
Mo 42 7
B 51 41
Mg 18 15
Ca 2631 2004
Zn 1177 888
P 916 1067
Ag 0 0
Mn 5 0
V 0 0
Ti 0 0
Cd 0 0
W 0.0 0.1
V40 141 122
ST 0 -32
OXI 12 14
NIT 9 22
SUL 23 0

 

[The motor guy]

I could be totally wrong but I think that heads and blocks are usually sand casted. Which explains the silicon. The lead might be from any sealer used on the head gasket.

 

[The motor guy]

I'd say change the oil. Then see if it washes out on this change.

 

[vxcalais]

Thanks guys. The heads are reconditioned, so not sure if any casting sand present. Car is at 280,000k's etc. New recoed heads etc on for around 9000k's.

I know the heads are fitted dry on the GM engines. Intake manifold gasket dry, except for front and rear rubber ends, blobs of silicon places in corners to seal.

Could coolant be entering the Crankase ?

 

[Trav]

Is the coolant level dropping?
Its possible the silicon is from the sealant and the lead may be from never seize (most is lead free today but there is still some of it with lead)if you used it anywhere.

 

[Rand]

I'd try a shorter interval and see if the tread is downward.

 

[vxcalais]

I didnt notice any water in the oil. Also on the dipstick etc. Even now on the new oil there is no sign of water. I had to do a couple top ups maybe 100ml max.

Should i test at 3000km ?

 

[SubLGT]

Were both oils run the same distance? It looks like you also have increases in Al, Cr, Cu, and Sn which would imply that the engine is ingesting dirty air.

 

[vxcalais]

Similar. Could those wear figures also show coolant ingress ?

 

[SubLGT]

I don't think Na and K are high enough to indicate coolant in the oil. You probably have a bad air filter or a leak in the air intake system allowing air to bypass the filter.