oil loss on trackday

tomcat · Post by **tomcat** » Thu Nov 22, 2012 11:34 pm

gary@apt wrote:valve guides must be fine or you would see smoke on overrun,

do you do many miles on road? if its burning oil will show up on plugs,

turbo probs would show smoke to.

by sounds of it its rings if you cant see it smoke,when you had pistons out was top of pistons oily or dry

probably 2000 miles a year
plugs always look ok when I have checked them however i will check again tomorrow though.

From memory there was quite a bit of what looked like burnt oil/carbon on piston tops some worse than others-shame I didn't take photos
plus valves and back of valves were well carboned up in not that many miles which surprised me

I also don't thinks its turbo as its a bb unit with very small oil feed cores only done about 5k miles

It smells bad especially when driving slow with the window open

Scott

tomcat · Post by **tomcat** » Fri Nov 23, 2012 11:57 pm

I just had a look at the plugs to me they look pretty spot on?

exhaust tailpipe is very black and sooty not wet though

scott

stockcar · Post by **stockcar** » Sat Nov 24, 2012 7:49 pm

you mention "forged" pistons so presumably its been bored/honed.............

unless done properly this can cause the issue you are suffering as can the bores being "glazed" due to incorrect bed-in

gary@apt · Post by **gary@apt** » Sat Nov 24, 2012 7:51 pm

them plugs look like burning oil to me,you got any close ups

tomcat · Post by **tomcat** » Sun Nov 25, 2012 9:13 am

think you both might be right

It might be due to the honing as I didn't get it bored or honed -i did it with a diy honing tool and didn't get rebore as it was low mileage, when I last checked the pistons the bores did look a bit shiny.
The std bore is 84.45 and the pistons were 84.5mm -I only lightly honed as I didn't want to oversize the bores accralite reconed that if anything the engine would be a bit tight.

I also checked the compressor outlet to intercooler pipe and there is a carbon oil build up in their, but its not wet and compressor intake is well stained in oil as is intake pipe after breather pipe enters pipe. also only a small amount of play in turbo shaft so think turbos ok.

The catch can has about 10mm of oil in bottom of it.

I had a word with towler engineer yesterday and he was also convinced that its excessive blow by caused by poor bore honing or ovaling - I am going to strip it over the winter and get towler to check the bores with bore gauge to see if it needs rebore or just hone and new rings.

Can't leave it as its making me feel ill driving!

cheers
Scott