I've got a set of total seal gapless rings, JE forged pistons (.040 over). The setup has been run for about 20 minutes, idle-3000 rpm.

I noticed that I was blowing a little bit of air out of my valve cover breather. Removing the breather, there is a steady stream of air out of the valve cover.

I called LC Engineering and they said that it may take a while for moly rings to seat. Anyone have any experience with this? I don't think I had this much blow by on start-up, but not for sure...

I'll probabably run a compression test when I get back to look for trouble...


-D

Air is not the same as blow-by. Any engine is going to push some air out of the crankcase. Does the 'air' smell like exhaust?

Dunno what else it could be, it's a pretty solid flow. I don't know how it smells as I'm running on open header and everthing smells like exaust...

Think about it, you have a sealed crankcase and you have four pistions 90 degrees apart moving up and down there is going to be air movement coming from the CC. Smell it if it smells like exhaust it is blow-by, it it smells like oil it is just air from piston movement. How long for the rings to seat, depends on how well the the x-hatching in the cylinders was done. Twenty minutes is not long enought to seat rings!!!:D

Well, I'm getting some oil in that breather, so that's an indication of blow-by.

OK if 20 min isn't time for them to seat. So it's "normal" to have this condition on a "new" motor? Same behavior that I ended up rebuilding the motor for, so it's pissing me off...

I'm told that normal rings should seat almost immediately, but moly rings may take a while... LC Engineering and Ted (engnbldr) tell me to take it out and drive the crap out of it... (load the motor). I'll do that as soon as I get the throttle linkage worked out...

I will run a compression test tonight, if there is a diff, then I'll be concerned.

thanks for the responses.

-d

Moly rings (top) will seat once the motor is loaded, the second ring is the time taker in your case. You're running a single moly set, the number two ring is ductile iron, same as your block, so this ring takes time to seat. Forged pistons for toy applications are run at a minimum @ .003 piston to cylinder wall, don't expect a quiet running engine, and do expect oil cunsumption.
The migration and "breathing" you see is blowby, but until you aquire some numbers on the combo you're running it's just too early to tell.
And for the gent talking about normal "air" movement by pistons and a sealed crankcase, toyota crankcases are not sealed, they are exposed to the timing assembly, valvecover, and so on, and this is all exposed to atmosphere.

I ran a compression test last night:
125
137
125
125

I'm 8.5:1 CR.

So, everything seems to be in order.. #2 is maybe more seated than the rest. I'll load the motor this weekend, I was just afraid of having one cylinder with problems.. My compression indicateds (to me) that I just haven't seated the rings.

total seal rings when seated will have less than 1% leakdown, a set at over a 100k miles will usualy be around 2-3%

a set of standard gaped rings has 5-7% leak down when seated, up to about 15% when worn.

compresion tests dont realy tell you if they are sealed, what you want to do is a leak down test.

and if there is air coming out of the v/c it is blow by. if its a steady stream and the pcv valve is still hooked up then they arent sealed! the pcv valve shuld actualy cause there to be vaccume in the crankase. a tight motor with good ring seal will produce up to about 5-7" of vaccume in the crancase.

Originally posted by Tim@DOA
And for the gent talking about normal "air" movement by pistons and a sealed crankcase, toyota crankcases are not sealed, they are exposed to the timing assembly, valvecover, and so on, and this is all exposed to atmosphere.

Tim, I'm pretty sure he meant 'sealed' except for the PCV and breather. Those are the only 2 openings to atmosphere right?

The breather would be open to atm, yes, the pcv is a vacuum item. The way it was written meant that the rotating assembly was "making air."

PVC valve is in, but not connected to the carb.
I know that I can't tell how well the rings are seated w/o a leak down test, but I thought that I might have had a single cylinder that failed to seat. Based on the compression test, that's not the case.

Tim, is this kind of blow-by normal with a new motor with Moly rings? I'll try to have it on the road tonight.

The issue is not just the rings, it's the piston composition. Forged slugs for toyota applications require large clearances, they're race formatted units, they're not like offerings for domestics and hondas, etc. Why the marketplace has not caught up I don't know, but regardless, high silicone content pistons like yours are going to slap, knock, use oil, and feature the lovely everpresence of blowby. It will diminish some, but not completely. Those comp. figures seem odd, what's the written static compression of the pistons you've used?

The static compression should be 8.5:1. The reason for the low compression is the install of a camden supercharger.

I figured out part of my problem. The copper head gasket I was using sucked BADLY. IE - I was puking water all over the place and not getting a good seal. My head studs were properly torqued and the block had been decked.. I really don't know why it was like that, other than I did notice that the copper gasket left a lot to be desired in terms of properly positing the hole for water and oil flow.

I swapped in a fel-pro (stock) gasket this weekend, things are 100% better. No leakage, still some blowby, but not enough to bother me at all. I haven't run a compression test again.

Next mystery - my camden blower I was told was setup for 4-5 psi. Superchargers are RPM dependant beasts, but I'm getting 4-5 psi at maybe 4900-5400 rpm. It's handing that boost fine, but it's too far up the power band to be useful. I don't know if this is normal for my blower or not... Opinions. I dunno if the charger itself might be in need of new seals.

I've contacted AdkinsRotary, which now owns Camden, but judging by their previous responses, I think they sold all the rights the LC Engineering. This thing is still in a prototype stage over there - no install manual, no throttle cable brackets.. They do list it and have dyno'd it, but I think that's about it.

-Darin

Those figures are in line for a 8.5 static. Copper is a race only piece and constant retorques are the norm. Camdens have a 10 lb pulley and a 14 for those who dare ;-) If you're suffering from low boost until those rpms I'd think your cam has too much overlap.