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Discussion Starter · #1 ·
So, I rebuilt my short block over the winter which included measuring the cylinder bores, honing the cylinders, milling the decks, milling the heads, having them cleaned and checked, replacing the crank, rods and pistons with those of a 3.5L, new rings and bearings.

It's been a couple thousand miles since and more often than I like I get a puff of blue smoke at start up and when accelerating. It comes and goes. Sometimes no smoke, sometimes a little sometimes a lot. I'm thinking the start-up smoke is due to the heads being cleaned revealing leaking valve stem seals. But the smoke on accel is clearly the rings. Do I need to do anything the help the rings seat? Use different oil? I've been using regular 5-30. Now that it's warm, should I switch to a 30weight non-detergent?
 

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Discussion Starter · #3 ·
Ring gaps were off-set, used dino oil and didn't really do any sort of break-in. Just started driving it.
 

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You should do a bunch of runs to full RPM at varying throttle positions. Then drive on the highway and vary the RPM every few minutes. Also try and do as much engine braking as possible. If the engine does not stop burning blue after 200 miles or so then your going to be stuck with it forever.
 

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I forget where I read about breaking in rings, specifically about the 3.2's & 3.5's. But if I remember correctly, one of of the manuals somewhere advised finding a long, empty street and driving the vehicle up to 50mph and then just letting off the accelerator (like an engine break) until it slows down to 30mph. I forget how many times it said to do this.

I'll see if I can't find that information.

-edit- Make that "seating the rings" not "breaking in rings". A little detail, but important difference. :)
 

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Chiron said:
I forget where I read about breaking in rings, specifically about the 3.2's & 3.5's. But if I remember correctly, one of of the manuals somewhere advised finding a long, empty street and driving the vehicle up to 50mph and then just letting off the accelerator (like an engine break) until it slows down to 30mph. I forget how many times it said to do this.

I'll see if I can't find that information.

-edit- Make that "seating the rings" not "breaking in rings". A little detail, but important difference. :)
Read my link, it's basically the same deal. Hard acceleration & hard engine braking.

~psguardian
 

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Discussion Starter · #7 ·
I'll give it a whirl but according to that article, it may be too late.
 

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Engine braking on a long down hill. or even just let off the gas pedal at speed. Have someone trail you with the report.

Oiling on Acceleration, so soon after a rebuild? Something didn't go right?

There are a lot of different oil control ring style. Perhaps the rings and pistons were not the match made in heaven.

Poor Compression ring sealing, even with good oil control results in blow by, which leads to stuck rings.

Poor Oil control action just burns oil, no problems other than that.

I would suggest confirming the heads, since those pieces you did not rework (at least that is what I got from your description).
 

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Discussion Starter · #10 ·
psguardian said:
It may be at this point... Does g the puffing translate to notable oil consumption?

~psguardian
Oh yeah. It's drinking oil like there's no tomorrow.
 
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