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Leaking Front Cam Seals On Rb26, Any Ideas Why?

CruiseLiner

By CruiseLiner,
in Engines & Forced Induction

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CruiseLiner Mentor

CruiseLiner

Posted
Posted

hey guys got my rb26 with jun oil pump and tomei head restrictor and jun cams. the problem is the front cam seals wont stop leaking for some reason. im seeing 90-100psi oil pressure when its cold, and around 75psi when its warm and at full revs. would these leak from too much pressure? or maybe the head is getting too little presure from the restrictor and its not pushing the oil seals out enough to seal correctly?

anyone else have any ideas ? anyone had the same issues?

ive replaced the seals like 4 times now trying to fix it and still the same problems.

cheers

sweetr33 Experienced

sweetr33

Posted
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hmm thats tough. guess you've checked for obvious signs of wear on the end of the camshaft assuming its stock cam for groove wear seal rubs? When u replace the seals ur not dinting the seal face itself? this damages seals capability to seal. all obvious things i know n im sure u've checked but had to be said, good luck

CruiseLiner Mentor

CruiseLiner

Posted
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Posted
hmm thats tough. guess you've checked for obvious signs of wear on the end of the camshaft assuming its stock cam for groove wear seal rubs? When u replace the seals ur not dinting the seal face itself? this damages seals capability to seal. all obvious things i know n im sure u've checked but had to be said, good luck

hey mate, the cams are brand new, they are a really tight fit into the head where the front end is but i just thought thats becuase they are new. its not the seal surfaces as both of them leak unfortunately :down: i am thinking too much oil getting into the rear of the seal and cant drain out quick enough so its pushing past the seals. it was all fine when everything was stock (oil pump, cams, no restrictor, etc).

thanks for the help mate :D

Mik Experienced

Mik

Posted
Posted
hey mate, the cams are brand new, they are a really tight fit into the head where the front end is but i just thought thats becuase they are new. its not the seal surfaces as both of them leak unfortunately :) i am thinking too much oil getting into the rear of the seal and cant drain out quick enough so its pushing past the seals. it was all fine when everything was stock (oil pump, cams, no restrictor, etc).

thanks for the help mate :dry:

Did you put a bit of silastic on the front cam caps when you assembled it?

CruiseLiner Mentor

CruiseLiner

Posted
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Posted
Did you put a bit of silastic on the front cam caps when you assembled it?

silastic as in gasket goo? the gtr workshop manual shows nothing so i didnt put anything except the cam rubber seals in.

do u mean between the caps and the head on the joining surfaces? is this reccomended?

r33_racer Grand Master

r33_racer

Posted
Posted

Its normally there from factory. Same on the rear caps. Well when i stripped my 25 head down there was silastic there. Can only assume on a rb26 it would be the same if not similar.

  • 3 weeks later...
carl h Proficient

carl h

Posted
Posted

old thread but having the same problem on my rb20 thats been fitted with the n1 pump and restrictors in head, where exactly should i put the silicone, there looks like there is groove in the cam cap which should be filled?

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