blown383z28

iTrader: (3)

Hi guys, im wondering about a customers car again. I had the motor rebuilt by a very well none engine shop. it’s a 383 9.5 to1 comp. Motor parts all top of the line!!! (Forged etc.) I have it in the car with a D1, intercooler set up running 15-16 psi. He got about 725 miles on it and I decided to change engine oil. Not a big deal but I ended up grabbing synthetic oil. He got about 75 - 100 miles on and now it has massive blow bye.!!! I mean it looks like a smoke stack out the pvc on the intake. It has off road y pipe and I don’t see any thing coming out the exhaust. I called my buddy at the dyno shop and he said if they are a molly ring then it was way to early for synthetic oil now its got the rings glazed and they are basically junk!!!!????? What u guys think??? and this is at idle 700 rpm.

355z28

iTrader: (8)

your buddies right, you shouldnt run synthetic intil 10k-15k if you wanted to run it. Basically the only thing worth trying is getting some conventional oil, and a can of sea foam, change the oil and go out driving, vary your speeds a lot, 10-20, 15-35, 40-70 let the rings try to seat to the cylinder walls, try not to go at a steady rpm. Otherwise look at tearing it back down and throwing some rings in it, if he wanted to race it, and run synthetic right away put some cast rings in it, those only take about 800 miles to break in, hell half the people i know just go ***** to the walls with them as soon as they pull it out of the garage. Good luck!

AmericanMuscle33

Yep, what the guy above said...

Most likely un-seated the rings. Drain the synthetic, put some dino-oil back in it. I would suggest being very aggressive at trying to seat the rings this time around since you may be on limited time.

Work up to approx. 80% throttle position in 2nd and 3rd gear pulls. KEY is to do a long hard pull to approx. 5,000 rpm (or higher depending on setup) and lift throttle letting the engine brake you back down to approx. 2,000 rpm. Being on throttle seats the top ring, lift throttle engine-braking seats the bottom ring.

Good Luck!

EDIT: I just noticed you said it wasn't coming out the exhaust...hmm...unseated piston rings should have significant blow by. Should look like a blown motor if you're 50% + throttle going down the road. Maybe I'm interpreting your explanation incorrectly.

Oh, and if you break in this motor aggressively, I would be changing the oil and filter like crazy...

blown383z28

iTrader: (3)

Well I got a new one. My buddy at the dyno shop said pull the motor or try one of his dads old remedies. Run the motor around 2500 3000 to keep it running and put cleaning powder in the intake (comet etc.) after mass air flow and run it in the motor. Says its just enough to take most of the glaze off. Change oil and filter 2- 3 times, and hope for the best. ??????

Yes i did say nothing came out the exhaust but last time I started it looked like it had some smoke..??? Havnt driven it yet though.

1bdbrd

iTrader: (12)

You don't need 10-15,000 miles on the engine before you put synthetic in it. My truck has had 10w30 mobil 1 synthetic in it since it had about 3500 miles on it and the only oil loss is about a quarter to half a quart ever 5-8k miles.

2500-3000 is more like it.

TwoFast4Lv

iTrader: (8)

I usually put synthetic in around 1,000 miles on a street motor.

Old school.

Now I put it in on the first oil change. If the rings are not seated by then my machinest screwed up

SincalT/A

iTrader: (16)

I agree with the above post.750 miles is probably 15 hrs. of run time
and more than enough time to break in a engine.Try a leak down to see where your at.

94 F-body

iTrader: (1)

---X2---

hi officer

are you sure your not pressurizing the crankcase somehow through the pcv system now that it is supercharged. for example still using the pcv vent from the valve cover to the tb will send boosted air into the crankcase. just a thought.

Tony Shepherd

iTrader: (4)

I have first hand experience with synthetic oil on a new engine. Back in 1998 I built an engine for a guy and he put 400 miles on it and changed the oil to synthetic. It then started smoking and using massive amounts of oil. After pulling the engine back out for the tear down, I inspected the cylinder walls and low and behold it had blue(heat spots) in each cylinder. After researching what he did it was the synthetic oil that caused the problem. The rings were not seated yet and caused this issue. I do not recommend running synthetic on a new engine until about 2,500 miles or even more if possible.

355z28

iTrader: (8)

Ive always ran my engines at least eight. But this is a matter of opinion, i do what i know works. Sure you could probably run it a lot sooner, but that doesnt give me peace of mind. This is just my way, everybody does everything different.

The guy with the pcv idea has a good point a couple years ago i turbo charged a cavalier i kept blowin out the dip stick, way to much pressure going back into the crank case, i ended up making a catch can with 2 pcv valves that worked simular to a check valve, it worked very well for me.

LittleRedZ

iTrader: (5)

HI officer is the only person that knows what hes talking about here. Synthetic oil shouldnt make your car smoke like a train you should of broke it in with regular oil but you should be ok. Your problem is the PCV system is getting presurized under boost its normal with LT1 boosted cars. easiest and cheapest and best solution IMO is to buy the Evacuation kit from jegs, i think MR gasket makes it it comes with two breathers and 2 tubest that you weld into your header collectors at an angle you have to buy some heater hose from local parts store cuz it dosent come with the kit which only cost 30 bucks btw, then you connect the breathers with the tubest in the headers when your car runs exhaust constantly pulls out of valve covers...
problem solved you probably pushing oil out of of all kinds of places like dipstick,and engine gaksets. Install that kit and put some regular oil your rings will sit in no problem been there before.
good luck

Tony Shepherd

iTrader: (4)

Oh really....

I was just re-enterating about synthetic fluids...not about pcv ventilation. Ring sealing and crankcase ventilation work hand and hand. Rings will not seal with synthetic fluid on a fresh engine therefore causing blow-by......period. Now if the engine has 5,000 miles that would be a different story.

letsrun97z

iTrader: (7)

[QUOTE=Tony Shepherd;8202289]Oh really....

lol

SincalT/A

iTrader: (16)

[QUOTE=LittleRedZ;8200505]HI officer is the only person that knows what hes talking about here.


Thats a pretty bold statement.You should learn to constructivley disagree.He maybe right but, some of the guys here are not wrong.

AmericanMuscle33

Here's a visual of a Mr. Gasket Crankcase Evac kit:

moehorsepower

iTrader: (3)

Yes read his statement, Tony is correct, I know we are not talking about cam break in but there are oil additives and even break in oil that also help ring seating since todays oils eliminated the pressure additives not needed for todays roller cams. Also if the rings are full chrome molly they will take additional time for break in vs standard or single moly rings..

LittleRedZ

iTrader: (5)

Funny you say that yet you nor anyone else in this thread has said anything about crank case pressure just stuff about synthetic oil, i gurantee you if he used non synthetic oil from the start or now he would still have the same problem.
So everyone else that threw their .2 in about oil did not help the guy out any with the current problem he is having maybe educated him on what not to do in the future.

Tony Shepherd

iTrader: (4)

The main topic from the other people replying was about synthetic oils. I was giving my advice on synthetic oils and ring sealing....just because I did not mention anything about crankcase ventilation does not mean I do not know what I am talking about. It will take more than a pcv modification to fix his current problems. Notice the engine was fine UNTIL he put synthetic in it. The damage is already done.

LittleRedZ

iTrader: (5)

Like i said before been there done that he should be fine as soon as he puts on a right evac system on it, i can almost gurantee you he was driving it easy during brake in and then changed the oil started getting on it alittle and it started smoking like a train.