Project Honda EJ Civic: Building the B18C1 Part IV

Once the lapping was complete, we installed new valve stem seals.  If you have your B series head apart, spend the few extra bucks to replace these as worn seals will allow oil to escape down the valve and into the combustion chamber.  This will lead you to chase around an oil control issue which you will surely blame on your piston and/or ring manufacturer.  Shame on you. 

Some engine builders advise against using assembly lube on the valve stem as they fear it may contaminate cylinder walls and prevent the piston rings from breaking in properly.  I say just don’t be stupid about how much you apply and the piston rings will be just fine.  Generally, valves have a very smooth, wear-resistant nitrided surface so the valve would most likely be fine at start up even with just a light coat of WD-40.

 

Leave me alone! I know what I'm doing… or do I?

After you’re done posting a cool picture that convinces your Facebook friends that you’re a master engine builder when you’re really not, install the OEM hardened steel lower spring seats and then confirm that the valve stem installed height is within the service limit. The valve stem installed height is the distance from the cylinder head surface (where the lower spring seat sits) to the top of the valve.  If an excessive valve stem installed height goes undetected, it could result in less spring pressure and potentially result in catastrophic engine failure.  If your valves or valve seats have been re-cut or replaced, this step becomes even more critical. 

 

Supposedly, a smart guy named Archimedes once said, “give me a lever arm long enough and a fulcrum on which to place it, and I shall move the world.”  Well, Chuck Johnson (that’s me) says: “Give me a lever arm, a beer, and an extra hand and we can finally get this damn engine together using this valve spring compressor.”