TheSamba.com :: View topic - oil leak between head and cylinder, only need retorque?

Fri Oct 28, 2011 10:11 am

Hi, this is a picture and sometimes even get to hear as a compression leak (plop plop plop) when accelerated, the engine was repaired 7000 km ago.

thanks

Fri Oct 28, 2011 10:15 am

If it leaking like that in that short of period of time.
Cylinder head more than likely need to be resurface and top of barrels/cylinders need to be checked.

Fri Oct 28, 2011 10:27 am

That's usually a bad rocker stud seal.

Fri Oct 28, 2011 11:15 am

[email protected] wrote: That's usually a bad rocker stud seal.

No, on another occasion I had the same problem and so the head could be seen in a darker part of the escape of the explosion

tanks

Fri Oct 28, 2011 11:36 am

that is leaky head studs. You need to coat the bottom side of the rocker box washer with RTV to prevent that leakage.

Fri Oct 28, 2011 11:42 am

I had this happen until I had case savers installed. The head studs vibrate loose causing the head to come loose resulting in both oil and compression loss. Re-torquing would only solve it for a short time...I had to tear the entire engine down and have the case savers done....now, dry as a bone.

What are your case numbers? Are the studs 10 or 8mm?

Fri Oct 28, 2011 11:44 am

JeivoPe says he can hear the compression leaking when engine is put under load.
You can see that the cylinder has been pounding into the head,
You can see the oil on the cylinder head surface that surround the cylinder.
I don't see any oil leaking from rocker stud or from head stud area.
If was leaking from those two area it would be closer to rocker box area.

Fri Oct 28, 2011 12:11 pm

all that dried on black $(*$#)& is oil.

If the head is not tight, the washers are not sealed against the head.

Fri Oct 28, 2011 12:23 pm

Yes I know what the black crap is and I see where it is coming from between the cylinder and head.
Seen thousands over the years of working on them.
Yes it from loose cylinder heads from over heating or pulled head studs.

Fri Oct 28, 2011 1:11 pm

the picture wehere you can see that the cylinder has been pounding into the head was when I had enough deck.

now:
deck is 1mm
have a 8mm studs and case savers
i put RTV in washer for prevent leakage
Block is AS21 from brazilian bus of 92 motor code UG
1584, twin solex 32/34 and c25

i think no pulled head studs
is posible studs damage for over heat?
i try retorque?

Fri Oct 28, 2011 4:35 pm

With out a doubt, 1,the head is no longer square to the cyl NEXT to it, remachine it
2, check for a split barrel

Fri Oct 28, 2011 7:17 pm

Yes the head need to be resurfaced(also known as flycutting) to have a true surface for both cylinders to set against.
Cylinders also need to be check to see if flat across both of them.
If cylinders came loose they may have pounded into case causing cylinders to be at two different heights which cause them to never seal to heads.

Mon Nov 21, 2011 12:08 pm

Another theory that has been around me is the possibility that there is insufficient space between the bumper and the header for when first gear decelerator hear a hit as if at that time collide

Mon Nov 21, 2011 2:15 pm

re torque it and see what it does, and use breakleen to kleen it off.my rocker studs dont go that far down,and if the washers are leaking it would usualy have more oilin the rockerbox aera.the head joint is leaking.it might need serfacing it might not.I just use reg sealer(liquid teflon,like what arp has)on my head studs/washers,all of them,upper &lower,both sides of the washer, so all torque the same.

Mon Nov 21, 2011 3:04 pm

Bill271 wrote: With out a doubt, 1,the head is no longer square to the cyl NEXT to it, remachine it
2, check for a split barrel

X2 on this.
Thats no leaky stud, its leaking right oit of the cylinder to head seal.
Pull the head, while your at it install a fresh set of chromoly head studs
from a reputable manifacturer such as CB, or Scat.

Tue Jul 01, 2014 3:43 pm

Im having the exact same issue. Case has case savers. should I pull the heads and cylinders off and just have them resurfaced?