Northstar 6 Speed (Page 14/20)
Will FEB 17, 09:40 PM

quote
Originally posted by AJxtcman:

I think that the Northstar gets cobbled together as well.



And we're seeing the results of doing that.



quote
Originally posted by Zac88GT:

I put the intake back on today and ran it for a while with the PCV disconnected and it was still smoking, so i shut it off and pulled the intake again. This time there was definatly a pool of oil on the backs of some of the valves. Probably a teaspoons worth on the backs of the #7 valves. I might still do the leakdown test depending on how i feel but it looks like it's gotta come out again. The real question is: Is it worth it to try and rebuild it again and have it bored and honed with new pistons and whatnot, or should i just buy a new shortblock from the dealer?



Unless you can find oversized pistons (maybe they're out there now...), you'll need custom slugs if you get your block honed. Mine is ending up at 3.670 bore (3.662 is stock, so it's .008 over). Don't take it to a shop that does mostly Chevies, though, as they won't be able to hone the bores correctly. You'll have better luck with an import shop that does a lot of work on Hondas and Subarus.
BMTFIERO FEB 29, 09:49 AM
Bump because knowledge is POWER!!!
buds MAR 04, 06:33 PM
What have you decided to do Zac ?

If it was me I would probably look for a low K used motor to replace but if money permits a brand new one would be sweet.
Steven Snyder MAR 04, 06:46 PM
Re-sleeving is not an option?
AJxtcman MAR 04, 06:56 PM

quote
Originally posted by Zac88GT:

I put the intake back on today and ran it for a while with the PCV disconnected and it was still smoking, so i shut it off and pulled the intake again. This time there was definatly a pool of oil on the backs of some of the valves. Probably a teaspoons worth on the backs of the #7 valves. I might still do the leakdown test depending on how i feel but it looks like it's gotta come out again. The real question is: Is it worth it to try and rebuild it again and have it bored and honed with new pistons and whatnot, or should i just buy a new shortblock from the dealer?



Just so I understand You removed the oil from the intake manifold correct?
Then you ran the engine without the PCV system attached correct?
Just to double check that again. you had both PCV hoses pulled or just one when you ran it?
If it was a ring problem that was so bad it would deposit that much oil on the valves you would have had smoke billowing out of the PCV holes in the valve covers.
You have not mentioned that so I am going to assume that is not the case.
Think about it it the rings don't seal the gases have to leave the crank case some how.
Now we have kind of ruled out rings.
How can oil get to the back side of the valves? Hmmmmmmmmmmmmmmm.

The only way it is possible to get that much oil on the back side of the intake valves with the PCV disconnected is from the intake valve guides.
When I say the guides I mean the oil must run down from the top side. The can happen from to much Valve Stem to guide clearance, Bad or incorrect valve stem seals, or a leak from the outside of the guide. I have seen several valve guides that had been damaged in installation on Northstars.
Hand down it is a Valve train issue
THE BEAST MAR 04, 07:38 PM
I hope this is not something that repeats every single time (Will and now you). I too rebuilt my engine and although is not yet running yet I wouldn't want to go through this.

Zac I can almost feel your pain bro (money and time invested...). I wish you the best luck and hopefully it is something that can be fix without you loosing your whole investment.

JG
Steven Snyder MAR 04, 07:56 PM

quote
Originally posted by AJxtcman:


Just so I understand You removed the oil from the intake manifold correct?
Then you ran the engine without the PCV system attached correct?
Just to double check that again. you had both PCV hoses pulled or just one when you ran it?
If it was a ring problem that was so bad it would deposit that much oil on the valves you would have had smoke billowing out of the PCV holes in the valve covers.
You have not mentioned that so I am going to assume that is not the case.
Think about it it the rings don't seal the gases have to leave the crank case some how.
Now we have kind of ruled out rings.
How can oil get to the back side of the valves? Hmmmmmmmmmmmmmmm.

The only way it is possible to get that much oil on the back side of the intake valves with the PCV disconnected is from the intake valve guides.
When I say the guides I mean the oil must run down from the top side. The can happen from to much Valve Stem to guide clearance, Bad or incorrect valve stem seals, or a leak from the outside of the guide. I have seen several valve guides that had been damaged in installation on Northstars.
Hand down it is a Valve train issue



You can't rule out ring sealing like that. What you say is not true.. Smoke does not have to billow out from the vent holes if he has a ring problem.
On decel the car billows smoke. This is true. There is vacuum in the cylinders because the throttle is closed. It's not generating blowby at this point. The cylinders are pulling up oil from the crankcase because the rings are not sealing..
AJxtcman MAR 04, 08:06 PM

quote
Originally posted by Steven Snyder:


You can't rule out ring sealing like that. What you say is not true.. Smoke does not have to billow out from the vent holes if he has a ring problem.
On decel the car billows smoke. This is true. There is vacuum in the cylinders because the throttle is closed. It's not generating blowby at this point. The cylinders are pulling up oil from the crankcase because the rings are not sealing..



He has oil on top of the VALVES

How can the oil get on top of the valves from a ring not seating? Remember he pulled the PCV
AJxtcman MAR 04, 08:11 PM
This is a black light picture. The oil has dye in it.


This is oil from valve guides not rings.




BTW I have a few Northstars.

[This message has been edited by AJxtcman (edited 03-04-2008).]

AJxtcman MAR 04, 11:09 PM
Hey this is a picture of the valve cover. It is not your problem.
Loose sealer


Lack of RTV and you can see that it had been sucking in oil.


The baffle