Cylinder head rebuilding guides and pointers

[s2_bo]

Hello,

I'm going to attempt to rebuild the head for my project engine this weekend.

Its been cleaned, skimmed and i have port matched it all round.

I had a search on here but couldn't find any step by step guides on head rebuilding.

Does any one know of any? Or have any pointers and tips?

Thanks in advance.

Bo

[S2central.net]

Not much to say other than rebuild in reverse order from strip down. Only things to watch out for are that observe the torque settings everywhere and make sure the VSOS are snugly in place.

I have the torque settings and order for the cams if you need it - you also need to line them up first !

Oh and finally you need a good way to lock the cam pulley when tightening its centre bolt - make sure not to stress the lil keyway there.

Use plenty of oil to lube the lifters and valves on reassembly and you are supposed to leave a freshly refitted head on the engine for a time (can't remember) so the lifters can prepare themselves. I would always handcrank any rebuilt engine a number of times to make sure all is good.

Oh have you had the valves lapped in already ? Thats a boring old job but important for a good seal.

Make sure to check all the valve springs are OK - look for any odd ones out.

Cleanliness and patience is the key to success here - access to an airline to blow all the oilways and such clear is useful - keep linty rags away.

Paul

[s2_bo]

Thanks Paul, thats a big help.

I just picked up the head from the machine shop. They have pressed in the new VG's and reseated the Valves so they they seal well.
The skimmed surface also looks spot on.


One of the valves is bent though Could i call in another favor? No idea why i didn't spot this before.

Torque settings would be a big help.

I presume with line up the cams you mean that the two O's (markers) on the cams meet in center position as they were when i took them off?

Ill have a go at it this weekend.


Thanks again.

Bo

[mcandmar]

Use plenty of oil to lube the lifters and valves on reassembly and you are supposed to leave a freshly refitted head on the engine for a time (can't remember) so the lifters can prepare themselves. I would always handcrank any rebuilt engine a number of times to make sure all is good.

Thats so true, last head i rebuilt took a few hours before all the lifters settled down. You dont need it on the engine just fit the cams and turn it over every now and again so each one gets compressed.

Oh and watch the timing marks for the exhaust cam when you fit it, trust me it will look right until you torque it down and then its a tooth out

[Flat on my back]

Make sure you get the cam caps on in the right position and the correct way round. THERE IS A DIFFERENCE. Not shouting

Do a dry fit on one of the caps and you'll see, do every thing up with a cap the wrong way round and its 'fecqed', so check twice fit once!

Good luck.

[S2central.net]

Well remembered on the cam caps - forgot that one. But they should feel wrong if you do them wrong before you start tightening.

Oh the best tip of all though I also forgot is to use a we dab of grease at the top of the valve so it temporarily glues the collets in place while you have the springs and stuff compressed. Almost impossible without some sort of goo holding them... And just be careful uncompressing them with the tool so that nothin jumps out. I always give them a gentle tap with a hammer to make sure the collets are locked in OK.

Paul


PS - Will dig out the relevant torque settings tonight or over the weekend.

[Knight Rider S4]

I did the cam cap one with last rebuild :-)........Same as Paul says about the collets for the springs ,a welding rod with grease on the end does the trick......A good spring compressor that has a good length for putting the collets in as well

[dubmeister]

I use this in work:
http://cgi.ebay.com/ebaymotors/TORCO...spagenameZWD2V
Great stuff-sticks like **** to a shovel-and will not run off if the head is left standing for a while.
Lube everything: valves,guides,tappets,springs,cams etc and give the head face a good clean with a brake/clutch cleaner-excellent stuff eg:
http://cgi.ebay.co.uk/12-X-Shell-Bra...QQcmdZViewItem

Torques for a 3b are:

head bolts: 1: 40Nm
2: 60Nm
3: 180 degrees

Cam sprocket: 67Nm
Cam Cap : 15Nm
Cam cover : 10Nm
Inlet Manifold :25Nm
Exh Manifold :25Nm (use new studs/nuts)

Good luck and remember- clean it -then clean it again

[dubmeister]

Sorry forgot
You can try this with the lifters:
Once the lifters have been cleaned etc put them in a bath of HOT oil, the hot oil will cause any air inside to expand and be forced out, don't burn yourself.. put the lifters open side down. Then allow the oil to completely cool, the remaining air will contract and be replaced by oil.. that will get them nearly full.
You can do this on the cooker (use an OLD pan) and do it while the wife/girlfriend/mother etc is out for the day:mischeif:

[s2_bo]

Thanks for all your help guys!!!!

Ill let you know how i get on.

Cheers.
Bo

[spink]

If you havnt already you may want to think about replacing the spring disc's,ive just been stripping down a recentley rebuilt ported head that im going to use and found the disc has shattered in the area where the inner spring sits on it.Thankfully there is no evidence of damage to the cylinder head.Will have a dig around in the bottom end and see if i can find the bits.

[spink]

Luckily all the bits had got trapped under the valve spring so were easy to find.The one on the right is a good one.

[4WheelDrifter]

That doesn't look pretty. I haven't found any like that yet.
Was that spring seat one from a car that had been through some of your track punishment Spink?

[spink]

That doesn't look pretty. I haven't found any like that yet.
Was that spring seat one from a car that had been through some of your track punishment Spink?

lol,no i always make a proper job if i knacker a head.

[Mark Halligan]

lol,no i always make a proper job if i knacker a head.

Was there anything 'different' about the head that may have caused that, cams etc?