Built new 383 and Got Blowby
Built new 383 and Got Blowby hi ,i recently built a 383 engine with Mahle pistons Rods and Eagle Crank,with King Bearing Metals,PRC stage 2.5 LS6 heads ,Fast intake 102 with TB 102,and TR stoker cam V.3, i cant find why im Having Blowby with the Dipstick and when im on full throttle at about 5000 to 6500 RPMS im having smoke coming from behind the engine, i will upload some pics if i installe correct my PCV system or what things you recomend me to change,sorry for the low quality of the pics,my Galaxy 4 was battery off this pics are from my Friends cel,thanks for your help!
TECH Fanatic
Joined: Jun 2011
Posts: 1,343
Likes: 8
From: Katy, TX
Your PCV is indeed setup wrong. The catch can and PCV valve are on the clean side, but should be on the dirty side. See this link:
https://ls1tech.com/forums/11059703-post70.html
However, this is not the reason that you are getting blow-by. When I first built my engine, I made the same mistake and set up the PCV backwards. I ran it that way for a few weeks and didn't get any blow-by.
https://ls1tech.com/forums/11059703-post70.html
However, this is not the reason that you are getting blow-by. When I first built my engine, I made the same mistake and set up the PCV backwards. I ran it that way for a few weeks and didn't get any blow-by.
Time to do leak down, and compression tests.
What do the plugs look like?
Other items to consider:
Ring broken on install.
Rings on upside down.
Insufficient ring end gap.
Oil ring rail not on correctly. [Overlapped?]
Incorrect wall hone finish.
Excessive piston to wall clearance.
What do the plugs look like?
Other items to consider:
Ring broken on install.
Rings on upside down.
Insufficient ring end gap.
Oil ring rail not on correctly. [Overlapped?]
Incorrect wall hone finish.
Excessive piston to wall clearance.
all good ideas sofar.
Just to expand on Old Geezer's ideas, people often MISTAKE "built" for built well, that is not the case. Most reputable local shops aren't even that good if you then take the engine to someone who really knows what they are doing.
Point being keep an open mind when looking for the problem, I have seen too many guys have too much faith in vendors they trust and refuse to see shoddy workmanship.
Just to expand on Old Geezer's ideas, people often MISTAKE "built" for built well, that is not the case. Most reputable local shops aren't even that good if you then take the engine to someone who really knows what they are doing.
Point being keep an open mind when looking for the problem, I have seen too many guys have too much faith in vendors they trust and refuse to see shoddy workmanship.
TECH Fanatic
Joined: Jul 2011
Posts: 1,074
Likes: 2
Its sad but I do agree with the 96capricemgr. I see it time and time again where people take their engine to a shop to be built and it doesn't come out like it should. Many shops can build engines for stock cars, but making high performance and or race motors is a whole another ball game that many shops aren't ready to play in. That being said this may be the problem with the engine it may not since we have no way knowing who built the motor. It may just be a simple pcv problem, RezinTexas pointed out it is run wrong. Do a leakdown test and go from there.
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Your PCV is indeed setup wrong. The catch can and PCV valve are on the clean side, but should be on the dirty side. See this link:
https://ls1tech.com/forums/11059703-post70.html
However, this is not the reason that you are getting blow-by. When I first built my engine, I made the same mistake and set up the PCV backwards. I ran it that way for a few weeks and didn't get any blow-by.
https://ls1tech.com/forums/11059703-post70.html
However, this is not the reason that you are getting blow-by. When I first built my engine, I made the same mistake and set up the PCV backwards. I ran it that way for a few weeks and didn't get any blow-by.
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Verdad Gallardo ill record a video of the blowby ,and see how the vapor comes from the oil cap and the catch can open,
http://www.youtube.com/watch?v=QXm9c...ature=youtu.be
http://www.youtube.com/watch?v=QXm9c...ature=youtu.be
I just rebuilt mine, actually 10,000 miles ago. Mine does the same thing out the oil cap, Im going to just keep driving it until something goes. Mine runs fine, just uses some oil.
Time to do leak down, and compression tests.
What do the plugs look like?
Other items to consider:
Ring broken on install.
Rings on upside down.
Insufficient ring end gap.
Oil ring rail not on correctly. [Overlapped?]
Incorrect wall hone finish.
Excessive piston to wall clearance.
What do the plugs look like?
Other items to consider:
Ring broken on install.
Rings on upside down.
Insufficient ring end gap.
Oil ring rail not on correctly. [Overlapped?]
Incorrect wall hone finish.
Excessive piston to wall clearance.
hi Old geezer,
tomorrow i will take to the shop to start checking the things you are asking,the bad thing is that the oil smoke is burning somewhere and start leaking from behind the engine,maybe in the crankshaft seal or what else can be from behind?
thanks for your help geezer
hi !my car also is getting a leak from behind of the engine maybe the crankshaft seal ,when i WOT the car it starts getting smoke and leaking ,Damm this is annoying! thanks all for helping me
If the crankcase pressure is great enough it will push it (oil) past the crank seal. Isn't Mobil a synthetic? Is that ok to break in a new motor?
Just watched the vid.
You REALLY need to do a compression and more importantly leak down test. That is a TON of blow by. Get that motor checked out.
After the tests, if you didn't build it yourself you need to go back to the builder. Assuming there aren't too many miles on it.
Edit: with only 200 miles I'd suggest talking to the builder.
You REALLY need to do a compression and more importantly leak down test. That is a TON of blow by. Get that motor checked out.
After the tests, if you didn't build it yourself you need to go back to the builder. Assuming there aren't too many miles on it.
Edit: with only 200 miles I'd suggest talking to the builder.
Last edited by Exidous; Jul 28, 2013 at 11:43 PM.
hi,,i was thinking about the same,i think the excess pressure is making the seal leak ,the oil is not Mobil 1 ,is a Regular Mobil Super 7500 Mineral Oil,i was thinking put Mobil 1 before 1000 miles.
thanks!
