Hello all,

I have a 2007 Honda Fit Sport (manual) and lately I have been noticing a slight ticking sound coming from the engine. I decided to check the oil pressure in the block. The mechanical pressure gauge showed very good pressure (about 70psi)


so then I took off the valve cover and saw that the rocker arms were all in good shape. But when I started the car, the oil didn't really shoot out of the small rocker holes like I expected, but rather it just oozed out gently. So I connected another gauge to the channel above the camshaft, which supplies the oil to the rockers. Unlike in the block, the oil pressure was very LOW (about 5psi).


So what does this all mean? Is this normal pressure? Or should it be the same as in the block? One mechanic told me that it should be the same, and that since the pressure that supplies the oil to the rockers is very low, THAT is what is causing the sound in my engine.

Any input is highly appreciated! Thanks.

 

Just where did you measure the oil pressure and at what rpm?

 

To the channel above the camshaft

 

Just how did you do that? more importantly, what was the rpm?

 

As long as the valve cover was off, did you check valve lash? Unless you have a noisy injector, a loose valve would be the most likely cause of ticking.

Oh, and if you enjoy driving your car hard, you might want to run a 5W-30 oil rather than the recommended 5W-20.

 

Why 5W30. ?

 

Manufacturers who sell cars that are driven "enthusiastically" will often spec a "heavier" oil.

Two examples that I know of are:
Civic Si: Regular Civic = 5W-20, Si = 5W-30
Toyota Celica: 5W-30. Exact Same Engine in Lotus Elise: 0W-40.

Realize my recommendation is JMHO. No flames please.

 

Not so. The only reason for choosing more viscous oil is age or tolerances in rebuilt engines.
Cars with 100 k miles may need 10w-30 instead of 5w-20 because the tolerances between lubed parts has increased due to wear. Thats especially true when conventional hydrocarbon oils have been used. Wear is considerably reduced with synthetic oils from recognized suppliers like Mobil, C Castrol, or others.
The most important attribute of an engine lubricant is its ability to avoid 'tearing' when spread out in thin sheets and leading to failure; thats the reason syntrhetics are so much better than conventional oils. And synthetics don't wear out as fast as synthetics; heat and prfessures in lubricated parts wear the oil much more quickly in conventional versus that in synthetics. Thats measureable by the change in visdcosity. thin convention oils used in severe service will fail far quicker than synthetics and are particularlr prone to failure for the first 50 miles after an oil change. ask why, its a good Bunkie Knudson story. Knudson rose to President of GM after confronding his superiors by solving his left-handed monkey wrench assignment.
There is a good reason why less visous oils are preferred in newer engines; thinner oil pentrates the fine tolerance gaps much better and of course having as much of the contacting lubricated parts coated with films or sheets of oil as possible is invaluable in reducing horsepower and mpg robbing friction. Any dyno master can attest to hp difference between synthetic and conventional oils; some can point to mpg reductioons too.
Comparing the design specs of engines from different sources or purposes is not useful, even if the engine is used by the same manufacturer, as Honda, or used by two manufacturers, especially if one is Lotus. And Si's versus standard; tolerances affect the horsepower too and viscosity is chosedn to match.