Syphus

I've recently rebuilt my motor. Pretty much every is new except for the block and the head itself (valves, springs and retainers etc all new) but im getting oil in cylinder 4 (furthest right) Any ideas on what could cause it? I've thought that maybe I didnt run it in properly but then id expect all 4 cylinders to exhibit a similar issue.

Im starting to freak out because its cost me quite a bit (Pricing in Australia for this stuff is messed up!)

Cheers

4b11slayer

How many miles? How much oil? Compression test? Leak down test? You sure it aint valve cover tube seal leak onto plug?

Syphus

Fresh built about 10000km on it. I’m genuinely not sure. I don’t know too much about the internals and stuff of an engine this the asking for help. Was wondering if there’s any quick checks I can do rather than just going straight to ripping the motor out again.

4b11slayer

Compression test. Leak down test

bsh

iTrader: (1)

Piston rings on that cyl installed wrong?

Syphus

I’m wondering if that’s the case. Or just poor workmanship

barneyb

A quick check - how about the dip stick? How much oil is it using? You should know having driven it 10000km. If no oil is disappearing from the crankcase then nothing is wrong.

Syphus

I’m loosing like 1-1.5 quarts every 2 or so weeks.

kaj

iTrader: (60)

1. Comp test. If low:
2. Leakdown test.

Oil could be from a bad valve seal, ring gaps not set correctly, or entering from the intake mani (though there would probably be oil in other cylinders).
Any oil anywhere in the intake tract?

barneyb

Neither a compression test nor a leak down test is a valve seal test. However, negative results point to valve seals.

kaj

iTrader: (60)

I don't think anyone said a comp/leakdown tested valve seals.

Syphus

This is all great info! At least now I have a better understanding of what could be wrong. I’m also crapping myself because if it’s rings then I’ve paid a whole lot of money for what amounts to nothing

RightSaid fred

You're not going to fix it without pulling it all apart.
When you pull it apart, you'll find out what's wrong.

You'll also find out that the tests you've done to find it out, they don't work.



Often with a new engine that's smoked from day one, it was honed wrong.
Maybe not though?
Maybe the ring gap is wrong?
Maybe piston to bore clearance is wrong?
Maybe insufficient clearance from top of valve guide to retainer , too much cam lift?


But if it's only a problem with cylinder 4?
That one runs leanest, gets more air, detonates first and most.


You didn't mention the max boost that it's had?

barneyb

No one did. I made this comment because Syphus wrote, "I don't know too much about the internals and stuff of an engine...".

kaj

iTrader: (60)

Ooooh LOL. Your comment was after mine, so I assumed.