The Forward Look Network
The Forward Look Network
Search | Statistics | User Listing Forums | Chat | eBay | Calendars | Albums | Skins | Language
You are logged in as a guest. ( logon | register )

4 bolt 6 bolt BB valve cover question
Jump to page : 1
Now viewing page 1 [50 messages per page]
View previous thread :: View next thread
   Forward Look Technical Discussions -> Engine, Exhaust, Fuel and IgnitionMessage format
 
Apollo 61
Posted 2019-08-03 12:26 PM (#585574)
Subject: 4 bolt 6 bolt BB valve cover question



Extreme Veteran

Posts: 426
10010010010025
What year did they stop making 4 bolt big block valve covers and start making 6 bolt covers? Recently I've seen 6 bolts in 62s and 4 bolts in 63s?
Top of the page Bottom of the page
57chizler
Posted 2019-08-03 1:42 PM (#585577 - in reply to #585574)
Subject: RE: 4 bolt 6 bolt BB valve cover question



Expert

Posts: 3291
20001000100100252525
Location: NorCal
The change was made midyear in the 1963 model year, 12-04-62 or thereabouts. If you saw 6-bolts on a '62 it wasn't original.
Top of the page Bottom of the page
Apollo 61
Posted 2019-08-03 2:31 PM (#585581 - in reply to #585577)
Subject: RE: 4 bolt 6 bolt BB valve cover question



Extreme Veteran

Posts: 426
10010010010025
Thanks, I take it that this was done to prevent oil leaks. Is there problem using 4 bolt covers/heads with oil leaks or was just a precaution from Chrysler?
Top of the page Bottom of the page
1960fury
Posted 2019-08-03 4:36 PM (#585587 - in reply to #585581)
Subject: RE: 4 bolt 6 bolt BB valve cover question



Expert 5K+

Posts: 6324
50001000100100100
Location: northern germany
Apollo 61 - 2019-08-03 2:31 PM

Thanks, I take it that this was done to prevent oil leaks. Is there problem using 4 bolt covers/heads with oil leaks or was just a precaution from Chrysler?


Yes, there was a problem, that doesn't mean they all leaked, it just need some extra carefull assembly. 2 problems (not so much the number of bolts) the sealing edge isn't machined, it is a cast surface. The other: They made a major desing fault, when you shut of the engine, the oil level of the oil "sump" in the head is always a bit higher than the outer (lower) cylinder head ridge. They could have easily prevented any leaks just by rising the ridge a 3/8th of an inch or so.

Edited by 1960fury 2019-08-03 4:37 PM
Top of the page Bottom of the page
Jump to page : 1
Now viewing page 1 [50 messages per page]
Jump to forum :
Search this forum
Printer friendly version
E-mail a link to this thread



(Delete all cookies set by this site)