VortechC5

iTrader: (6)

My 427 (< 2500 miles) has been using a quart of oil in 500 miles or less. I have been told that there is some visible smoke on har acceleration. I pulled the drivers side header off to install an oil cooler and found a problem. The exhaust port of #5 is quite oily. The other three are dry.

What is the best way to troubleshoot this this problem?

This thing had better not need a rebuild with so few miles on it...

03 BUSA

iTrader: (25)

That sounds like a valve seal issue.

VortechC5

iTrader: (6)

Thanks. How can I verify that? If I do a leak down (excuse to buy a new tool) and it looks ok would that point to a valve stem seal for sure?

Haans249

iTrader: (24)

No, how is your PCV system run?

What pistons are used? What stroke?

Replace the one valve steam seal and see if it helps.

LS6427

iTrader: (2)

Yeah, hitting the pedal hard from a roll and getting that initial cloud of smoke usually means valve seasl(s). Could be broken ring too I suppose. I guess you could lsoe one seal and none of the others.

Sharpe

iTrader: (7)

Sorry to hear about your problem, but is that your engine bay in your avatar? Do you have more pics of that engine bay? Thanks.

VortechC5

iTrader: (6)

PCV uses the restrictor that came from SDPC with the engine. I run that from the valley pan through a catch can to vacuum source. I also run a line from the passengers side valve cover through another catch can with a breather on it.

The pistons are forged flat tops (11.05:1 compression) and I run a 4" stroke with the 4.125" bore.

VortechC5

iTrader: (6)

Yes it is. The MSD coils are gone now though. They proved to be unreliable.

03 BUSA

iTrader: (25)

Very clean. I love when people take their time and do it right the first time. Attention to detail. A+++++

ImTheCeo

iTrader: (3)

I agree , very clean setup. Love the polished alternator. too bad you had to lose the coils.

See5

iTrader: (53)

Hope it is a valve seal.
If you can borrow a scope check out the cyl wall of #5. Worst case is there is some scuffing or something irregular there.

JUNK

Look here...I would get my *** under that valve cover, pull the #5 plug, remove both rockers, air up the cyl., remove springs/replace seals (1 at a time).......reverse order for assembly. Total time w/ parts in hand: Less than a six-pack (30-45min). Time worrying about it that last few days: well, a few days huh?

Do the leakdown but my $ is on the seals, big $ on the intake seal

VGLNTE1

iTrader: (1)

I have a SDPC motor and mine is doiong the same thing. I am running a 416 LS3 with L92 heads. Its eating oil like a mother and im blowing the dipstick out due to crankcase pressure.


guys, If I pull a header and the ports are oily, does that mean its a valve seal for sure?

I wasnt sure if SDPC lapped the valve seats. ? But i called and said they did.

BlownVette 2001

iTrader: (2)

It sounds like you have a PVC issue if or some really bad blow buy problems , i hope it's not the latter.

What kind of crank case venilation are you using ? Any forced induction or are you NA ?

VortechC5

iTrader: (6)

Been gone for a few days. I am pretty convinced that I have at least one bad valve seal. This shouldn't happen so soon but oh well. I pulled a couple of plugs and they look ok. Neither one is oily.

I think that I will replace all of them since if I have one bad one I may well have others that are hosed. Are stock valve seals the way to go? Do I just order L76/L92 seals or they all the same?

Has anyone seen a valve seal replacement DYI on the net somewhere?

Thanks.

VortechC5

iTrader: (6)

I am not seeing signs of crankcase pressure with mine. My dip stick is staying put.

Gen414

iTrader: (38)

Well, typically smoke on ACCeleration means rings, and smoke on DECeleration, seals. Does not mean it is not seals however, but that is typically the rule of thumb:
First start up, deceleration, long idle, or just at idle period is usually seals.

Under acceleration rings.

Again, usually, not always the case.

Good luck, nice ride!

VortechC5

iTrader: (6)

I finally took the car into my favorite shop and they found the problem.

They did a leak down and all cylinders were at 1% to 4%. No problem there.

I found oil in #5 exhaust port so they pulled one apart and there was the problem. The valve springs were installed at the wrong height (thanks a lot Livernois). When the valves opened they crushed the valve seals. Livernois said that the valve springs were good to .620 or something like that. I am only running .591/.610.

dannyual777

Its good that its not a ring issue. The shop will still have to keep the retainers from smacking the new seals. I'd much rather have to deal with this than a non-sealing ring issue!

VortechC5

iTrader: (6)

The shop recommended going with a Comp set of springs/retainers/locks that can be done in car without having to machine the spring pockets. They are supposedly good for .640 lift. They are going to make sure that the installed height is correct.