Small Block & Big Block Chevy Specific Mouse & Rat Motor Discussion & Conversions

zz572 problems....

Thread Tools
 
Search this Thread
 
Old 09-01-2006, 11:18 AM
  #1  
Launching!
Thread Starter
iTrader: (2)
 
lt1s10's Avatar
 
Join Date: Jun 2005
Posts: 245
Likes: 0
Received 0 Likes on 0 Posts

Default zz572 problems....

I have a customer who has a fresh longblock 572. When he decels from a plane (its one of two in a 36' cig. gladiator), he says it backfires; and blows off the oil cap. The back of the boat is covered in black soit. It has demon 1050s? It sounds to me like it has too much crankcase pressure- but why would it only blow out the cap on decel? The carb hasnt been touched since the last 572 was in. Maybe the needle isnt seating on one of bowls? The base timing is set at 24*. There is only 1.5 hours on the engine so far. Any thoughts??
Old 09-01-2006, 02:30 PM
  #2  
Launching!
Thread Starter
iTrader: (2)
 
lt1s10's Avatar
 
Join Date: Jun 2005
Posts: 245
Likes: 0
Received 0 Likes on 0 Posts

Default

Think Ive got it- Main jets were waaaaay to big. Gas was passing the rings and exploding in the crankcase. The boat was jetted rich @ sea level. We are at 6500ft.
Old 09-01-2006, 07:49 PM
  #3  
Teching In
 
Tiresmokin's Avatar
 
Join Date: Mar 2006
Location: Oshkosh,WI
Posts: 39
Likes: 0
Received 0 Likes on 0 Posts
Default

Had a Chevelle BBC that I HAD to get running in the middle of a Wisconsin winter. Guess I had too much gas in the crankcase, it backfired and blew a valvecover right off! I wasn't laughing at the time, 20 years later and now it's funny.
Old 09-02-2006, 11:26 AM
  #4  
Launching!
Thread Starter
iTrader: (2)
 
lt1s10's Avatar
 
Join Date: Jun 2005
Posts: 245
Likes: 0
Received 0 Likes on 0 Posts

Default

Went down 8 jet sizes- per demon. See what happens.



Quick Reply: zz572 problems....



All times are GMT -5. The time now is 05:23 PM.