IPD sale XeMODeX - Experts in Volvo Electronics
MVS-Amazon link helps MVS!

Get email notification of topic replies. Log in or register (free). Amazon Link Buy anything with this and it helps MVS!

Small holes on s80 cylinder head

Help, Advice, Owners' Discussion and DIY Tutorials on the Volvo S80 model. Sometimes called an "executive car", the S80 was and continues to be Volvo's top-of-the-line passenger car.
Post Reply
Posts: 1
Joined: Sun May 20, 2018 12:02 pm
Year and Model: 2000 s80 t6
Location: Florida

Small holes on s80 cylinder head

Post by nathanepstein »

There are small holes on the top of my s80 cylinder head and was wondering if they are oil ports or just pockets. There is one for every valve (24). Should I worry about cleaning them out or are they unimportant?
User avatar
Posts: 1617
Joined: Mon Dec 01, 2014 1:28 pm
Year and Model: 2004 & 2016 XC90
Location: Minnesota
Been thanked: 176 times

Re: Small holes on s80 cylinder head

Post by SuperHerman »

I don't recall as working on this head is several years ago. Looking at the photo I would assume they are oil passages. Look for a clean one, take some carb or similar cleaner and insert the plastic pipe into it and spray. See where it comes out and what comes out. What does the other side of the valve cover look out - these may be oil passages to lube the upper cams. Do the same on the corresponding side of the valve cover - if they are oil passages you need those clean. You can spray and use a small wire, copper, and clean them out. If you have a carb wire set, use that. While spraying, be careful of back spray and your eyes.

They could be some exhaust emission passages - just don't remember. They still need to be cleaned out either way.

Head looks good though.
Posts: 6673
Joined: Fri Nov 12, 2010 9:25 am
Year and Model: 2004 V70R GT, et al
Location: Ponder Texas
Has thanked: 4 times
Been thanked: 276 times

Re: Small holes on s80 cylinder head

Post by jimmy57 »

They are drilled to intersect he lifter bores. For either hydraulic or the solid buckets. If you look at top of head you will see the "ditch" cast into head to carry oil along the full length of head on intake and exhaust sides.
Posts: 44
Joined: Mon Jan 02, 2012 11:05 am
Year and Model: XC90 R-Design 2009
Location: Vancouver

Re: Small holes on s80 cylinder head

Post by thebull »

Oil passages delivering oil to the tappets. Check your cover and you will see how they are matching with the oil canals there. Make sure that you spray compressed air in each hole to ensure there is no obstruction to the oil flow. The are very important holes.

Your pic is bringing some memories back 8) cheers
Flying on 2009 XC90 R-design 3.2L AWD and 2006 XC90 2.5T AWD. Volvo owner forever.
Post Reply
  • Similar Topics
    Last post