Bad Honda Civic Valves?

civic
honda
valves

#1

Has anyone ever heard of Honda Civics having bad valves in the early 1990’s. I just had my second valve job done in three years and it appears that the valves have internal voids in the metal which could lead to burn through under lean conditions.

Also, are the Civic computers (ECM) plug and play within various years or do you need to replace them part number for part number ? I had one stolen and the replacement’s part number was off by one on the last digit.


#2

What do you mean by valve job done???

Did they REPLACE the valves or just remove the heads and clean up the carbon???


#3

There is a maintenance item to inspect/adjust the valve lash every 30k miles in that vintage. If you do not do this it can lead to burned valves like you have incurred. Most people perform it in conjunction with a timing belt change as the engine is opened up anyway.


#4

Someone is not doing a proper valve job and/or the valve lash adjustment is not being checked and readjusted as necessary.

There are no “internal voids” in the metal causing the valves to go bad.
It is pure and simple a faulty valve job on their part or your failure to check the lash on a regular basis; preferably every 30k at the most.

Actually, whenever a valve job or engine overhaul is done the vehicle should always be brought back in about a 1000 miles to recheck that valve adjustment, which will have a tendency to close up a bit.


#5

Pulled the head, cleaned it, and ground the valves that were good and replaced the ones that were bad. $25 each new. one of the ground valves had metal pits in the seat area. Twice now.


#6

Its possible that the adjustment was the cause, but it was much less than 30K since the last valve job. The 1000 mile check was not done however.

There actually were small internal voids or pits in the metal of at least one valve. They showed up in the seat area when the valves were ground. I have it along with the failed valve.


#7

The valve and seats are not made with internal voids but it is possible that pitting can develop for a number of reasons.

  1. Tight valve lash adjustment leading to burning of the seat and valve. Tight lash means either they were improperly adjusted during reassembly or the valves tightened up too much after reassembly. The latter is why it is a good idea to go back in at a 1000 miles and recheck them.
  2. Ignition timing with too much advance which could then cause valve and seat damage.
  3. Whoever did the valve job not doing a very good job of grinding the valves/seats (seat contact too close to the edge of the valve, wrong valve face/seat angle, etc.) and/or not doing a good job of properly lapping them in after grinding.

As an example of how critical this can be, I had to replace not one, but both, cylinder heads on a Subaru once in which the owner had neglected the free, Subaru paid for, 1000 mile valve adjustment. This near new car only had 7500 miles on it and both heads were trashed so bad they were not worth fixing.