leaking from over flow bottle - RX7Club.com - Mazda RX7 Forum

3rd Generation Specific (1993-2002) 1993-2002 Discussion including performance modifications and Technical Support Sections.

leaking from over flow bottle

Old 01-15-19, 04:36 AM
  #1  
Junior Member
Thread Starter
 
filoralph's Avatar
 
Join Date: Jan 2013
Location: australia
Posts: 47
Thanks: 0
Thanked 0 Times in 0 Posts
leaking from over flow bottle

Hi,

i have a 2000 rx7 FD bridge ported bigger single turbo GT4294. i hardly drive it like ever maybe 1ce 2ce a yr. after a fresh build i didnt drive it for a good close if not a yr. it was running fine then when i started it the overflow bottle started to leak after warming up. it seems to keep pressure at the filler cap even after a day or 2. i flushed the coolant and put new fluid in. smoke came up but not as aggresive as if i was to have blown water seal jacket. would anyone know what this is or whats causing it to do this as i dont want to risk it being damaged. also how would i block off the water hose connecting to the turbo as i have the above turbo
filoralph is offline  
Old 01-15-19, 07:30 AM
  #2  
Viable fossil
iTrader: (14)
 
Sgtblue's Avatar
 
Join Date: Oct 2003
Location: Mid-west
Posts: 10,096
Thanked 149 Times in 129 Posts

Last edited by Sgtblue; 01-15-19 at 07:34 AM.
Sgtblue is online now  
Old 01-15-19, 10:34 AM
  #3  
Junior Member
Thread Starter
 
filoralph's Avatar
 
Join Date: Jan 2013
Location: australia
Posts: 47
Thanks: 0
Thanked 0 Times in 0 Posts
i done a pressure test and it still holds psi.
filoralph is offline  
Old 01-15-19, 12:52 PM
  #4  
half ass 2 or whole ass 1
iTrader: (110)
 
cr-rex's Avatar
 
Join Date: Nov 2011
Location: okinawa to tampa
Posts: 1,788
Thanked 45 Times in 42 Posts
You pressure tested the system but did you pressure test the cap? With that, typically when your overflow is leaking over like that you just need to bleed your system. You may not think there's air in it but there is. Get a lisle funnel and bleed it.

for capping off the coolant line, you have a few options. The first is to get a SILICONE cap and a non serrated hose clamp and just cover it. Those nipples that come off the water pump housing are actually inserts and can be removed. Some strategic taps with a hammer and they come right out. Then you can either get the ports welded shut or tap them to install a plug.
cr-rex is offline  
Old 01-19-19, 06:10 AM
  #5  
Junior Member
Thread Starter
 
filoralph's Avatar
 
Join Date: Jan 2013
Location: australia
Posts: 47
Thanks: 0
Thanked 0 Times in 0 Posts
when i try bleeding the cooling system with funnel i noticed it wont leak out of overflow only when cap is on filler neck. does this sound like bad seals or just air in my system? the car was barely driven when rebuilt under 100km but did sit close to a year not started. could this be the cause of the seals to go bad? would removing the ast help anyway?
filoralph is offline  
Old 01-28-19, 10:52 AM
  #6  
Top of the food chain!!!
 
ItalynStylion's Avatar
 
Join Date: May 2005
Location: North Dallas, TX
Posts: 802
Thanked 0 Times in 0 Posts
I agree you first need to try and burp the system of air entirely with the funnel approach. Do you have an AST still in the car? If so, you might want to replace that cap too. If that doesn't help, see my answer below...

I'll give you my experience as it relates to my last car. I had a very low mileage FD at the time (38k original miles) that was exhibiting identical symptoms. Mine would hold a pressure test for DAYS. The end result was it was a minimally blown coolant seal on the combustion side of the housing. What happened was the seal rupture was happy to hold 15-18psi indefinitely (pressure pushing IN) but the seal couldn't hold the immense pressure of the combustion cycle (a LOT more than 18psi). This lead to no coolant being leaked INTO the combustion chamber (thus no smoke) and it resulted in massive air pockets getting into the coolant system which pushed the coolant into the overflow tank.
ItalynStylion is online now  
Old 01-28-19, 04:30 PM
  #7  
half ass 2 or whole ass 1
iTrader: (110)
 
cr-rex's Avatar
 
Join Date: Nov 2011
Location: okinawa to tampa
Posts: 1,788
Thanked 45 Times in 42 Posts
Originally Posted by filoralph View Post
when i try bleeding the cooling system with funnel i noticed it wont leak out of overflow only when cap is on filler neck. does this sound like bad seals or just air in my system? the car was barely driven when rebuilt under 100km but did sit close to a year not started. could this be the cause of the seals to go bad? would removing the ast help anyway?
when using the lisle, coolant has no way of getting to the overflow for it to leak out. There are ways to test for a bad coolant seal. Look up the champagne test and also a pressure test will work. Unless you're like the guy above.
cr-rex is offline  
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
marshall13B
2nd Generation Specific (1986-1992)
5
08-07-10 11:34 PM
FC_EDDIE
2nd Generation Specific (1986-1992)
50
06-16-09 12:05 PM
NeCr0mStR
2nd Generation Specific (1986-1992)
3
03-07-06 05:30 PM


Thread Tools
Search this Thread
Quick Reply: leaking from over flow bottle


Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service

© 2019 MH Sub I, LLC dba Internet Brands

We are a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for us to earn fees by linking to Amazon.com and affiliated sites.