Questions and Answers
Valve Job Faux Pax
Q. Hi, I have a 1987 Honda Civic, 1488 cc, 16 valve, carbureted, P/S, automatic transmission, 140,000 miles, no ABS, A/C, rack & pinion. My question is about the auxiliary valves. What is their function? They do not extend through to the combustion chamber.
I have excessive oil consumption in the #2 cylinder and have had a valve job done three times. Each time after only 20-25,000 miles the problem is back. This time I have replaced the valve seals and hand lapped the other valves but left the "aux" valves alone. The problem is still there so I suspect it is something with the "aux" valve. I have not been able to find what is the purpose of these valves. Can I simply change the "O" rings and disable them?
Thanks,
GuidoA. In general, the reason for using two smaller valves is that they will provide a larger opening then one large valve. This increases the intake and exhaust flow. Now what the specific purpose Honda had in mind for those specific valves you mention, I don't know. The last time I did a valve job on a Honda all 16 of the valves were in the combustion chamber.
If you just decided to replace the valve seals and lap the valves after three successive valve jobs, then I would suggest you take the whole head to a machine shop and let them do the valve job. Replacing valve seals and lapping valves should be done with the valve job every time.
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