GX Valve Adjustments Decreased to 30k Intervals

[Curtis]

In a discussion with my service director I discovered that the valve adjustment intervals for the GX have been reduced (by Honda) to every 30,000 mi. I would imagine that the cng's lack of lubricating qualities makes it a bit harder on the valves.

So if you're getting intermitent miss' and you haven't had your valves adjusted in some time... that may be one of the first things you should check.

[freedml]

Re: GX Valve Adjustments Decreased to 30k Intervals

does that apply to all years?

[cnielsen]

Re: GX Valve Adjustments Decreased to 30k Intervals

Is this covered by the warrany?

[Curtis]

Re: GX Valve Adjustments Decreased to 30k Intervals

does that apply to all years?

I would suspect the answer would be yes. Remember, this is recommended, not mandated, but like I said... if you have a misfire situation... get'er done.

[Curtis]

Re: GX Valve Adjustments Decreased to 30k Intervals

Is this covered by the warrany?

The warranty does not, nor ever has, covered maintenace items.

[cnielsen]

Re: GX Valve Adjustments Decreased to 30k Intervals

The warranty does not, nor ever has, covered maintenace items.

On my BMW it did .

[Curtis]

Re: GX Valve Adjustments Decreased to 30k Intervals

On my BMW it did .

Sure it did. You paid for it in the up front price of the car. Another reason the price of a luxury brand is inflated... "free" service, "free" loaner cars, "free" massages while your cars in service....

With luxury brands being so soft in the market, you probably paid for it again in resale value.

I think I'll stick with the Honda... and the "free" donuts in the service dept.

[frankiem]

Re: GX Valve Adjustments Decreased to 30k Intervals

Sure it did. You paid for it in the up front price of the car. Another reason the price of a luxury brand is inflated... "free" service, "free" loaner cars, "free" massages while your cars in service....

With luxury brands being so soft in the market, you probably paid for it again in resale value.

I think I'll stick with the Honda... and the "free" donuts in the service dept.

free donuts? Amazing! I'm kind of a noob here, but what do you mean by a misfire? What seems to be the problem here? And these are all issues that can be fixed y taking in to the dealership ?

[TheBundo]

Re: GX Valve Adjustments Decreased to 30k Intervals

Misfire, likes it's "missing" when running. Perhaps a valve isn't quite closing, or not opening enough

[Curtis]

Re: GX Valve Adjustments Decreased to 30k Intervals

free donuts? Amazing! I'm kind of a noob here, but what do you mean by a misfire? What seems to be the problem here? And these are all issues that can be fixed y taking in to the dealership ?

There are 3 things which I've seen cause a "random misfire" code.
1) Valve adjustment
2) Coil pack cracked
3) Injector dirty/clogged

In Ca there is a 15 yr/150,000 mile warranty on emissions related parts. In your warranty book the last 2 pages define emissions warranties as they apply in your state. All above items are fixable by the Honda service tech if the tech is worth his salt. As long as you've had your filter changes done and maintenance kept up, warranty shouldn't be a problem, but again... valve adjustments are a service item like air cleaners.

[Michael]

Re: GX Valve Adjustments Decreased to 30k Intervals

The Maintenance Minder schedule for my 2006 Honda Civic GX says "Adjust the valves during services A, B, 1, 2, or 3 only if they are noisy." The vehicle now has 45,000 miles on it. I have never had the valves adjusted. The engine runs smoothly, the valves are not noisy, and the Malfunction Indicator Lamp has never come on. Should I wait until the valves become noisy and/or the engine misfires, or should I have the service done soon because the mileage is substantially beyond 30,000 miles? A valve adjustment service is not inexpensive and I would prefer not to have the service done more frequently than necessary.

Thanks in advance for your anticipated response.

Michael

[Techie]

Re: GX Valve Adjustments Decreased to 30k Intervals

Civic GX, unlike many modern cars, has solid lifters. Solid lifters are a set-up of my choice.

Unlike hydraulic lifters, solid lifters have threaded adjustments on them somewhere, depending on the engine set-up.

Typically, valves that need adjustment get tighter rather than looser. Valve seat gets pushed into the cylinder head as it gets struck with the valve face on average 1000 times a minute. As valve seat gets pushed deeper into the cylinder head (recession), the valve stem will ultimately get "taller" and this will reduce valve clearance. Valve adjustment will be necessary.

Both Civics and Integras use solid lifters. On gasoline models, exhaust valves will burn at about 130,000 miles if left unadjusted, depending on driving.

There is a good reason why Honda recommends adjustment of valves at 30,000 miles on CNG Civics.

In reference to CNG. CNG, unlike gasoline, it is delivered to combustion chamber in gas form. As gasoline travels through the intake systems, it evaporates somewhat, therefore cooling the intake valve and the intake valve seat. During the valve adjustments that I have performed on gasoline Civics, I have noticed that intake valves hardly ever needed adjustments. Exhaust valves, which received no cooling, always had to be adjusted.

When any engine (not just Civics) is operating on CNG, one important thing to remember is that CNG does non evaporate in the intake ports. Intake valves, which generally have softer seats, do not get the cooling they would if they were operating on liquid fuels. They will wear out sooner, they will need more frequent adjustments. Problem is even more noticeable in dry desert climates with higher temperatures. If valves are properly adjusted, they will last almost as long as they would on gasoline engine.

Liquid Propane Injection offers correction to valve heat issues, but LPG (propane) is currently more expensive than CNG and most of the use will fade in the past due to fuel cost and road tax issues.

The good thing about a Civic is that the cylinder head is not difficult to remove. A decent machine shop can change seats/valves for about $400, and then you are good for another 150,000 to 180,000 miles.

Pistons and rings will last a very long time on CNG. I have seen like new cross hatch pattern on cylinder walls of 250,000 mile engine.

[edo]

Re: GX Valve Adjustments Decreased to 30k Intervals

Techie, I have an 8th gen (09) approaching 30K, so getting ready to do a valve clearance check/adjust. Manual seems to make it pretty straightforward.
A few Questions:
1) Do I need to purchase a new valve cover gasket or can the old one be successfully re-used?
2) I notice in the manual that a liquid gasket (Honda part #) material is recommended in a couple spots on the valve cover gasket. Can I use Permatex Grey, and are there any do's/dont's with regard to application of the liquid gasket material?
3) My last valve adjustment activity was on a Honda---motorcycle. My dad taught me to always leave them a little on the open (loose) side of the tolerance to avoid possibility of valve burning. Same here?
4) Any final advice?
Thanks

[Darkstarchuck]

Re: GX Valve Adjustments Decreased to 30k Intervals

Anyone? be nice to know some of the answers to these questions....

[Darkstarchuck]

Shame on honda

SHAME ON HONDA.....

For even suggesting that the criteria be "noisy" for checking the valve lash! I did mine today, the exhaust valves were .100 mm too tight! The spec. is .250mm ± .020mm, and the measurement was .150mm. With only 88K miles, and no "noisy" valve train, it took just due diligence to discover that I was more than 1/2 way to a burnt exhaust valve. Honda should change the service interval wording, as in this day and age, valve trains do not typically get looser (noiser,) only tighter, as valve seat wear is the major issue.

Just like techie says, "Typically, valves that need adjustment get tighter rather than looser. Valve seat gets pushed into the cylinder head as it gets struck with the valve face on average 1000 times a minute. As valve seat gets pushed deeper into the cylinder head (recession), the valve stem will ultimately get "taller" and this will reduce valve clearance. Valve adjustment will be necessary."

Thank you for letting me rant.