another question.

The spark plug from cylinder 2 was missing about half of the prong. The guy said at the start they thought it was a spark plug failure, but then they pulled off the head and discovered the cylinder scoring; and from this have said that the heat generated from the cylinder scoring against the piston has generated the heat which 'vapourized' the bit of spark plug that cracked off. They said its the heat which broke the spark plug.....Can i argue that it was the spark plug that failed, and the remaining piece of spark plug which has come off has scored my cylinder wall??

 

Their story sounds like a crock of shit. It's much easier to believe that the scoring started from a broken-off piece of spark plug.

That said, how low was the oil?

 

You have a MY'00. Was the spark plug recall ever done on your car? If not, then you may have a course of action. The new plus have a stainless steel crush ring and Honda increased the torque spec because the old plugs were backing out and causing cylinder grenades.

 

I agree, sounds like a piece of broken spark plug rattled around inside the cylinder leading to the scoring. If it was an oil problem the big end bearings would be the first to go. I've never seen bore damage caused by oil starvation, even when the engine was driven to the point of melted bearing from lack of oil pressure.

Also, If it was due to lack of oil why arent all the cylinders damaged.

I would get an independent automotive engineer involved. Give them copies of the spark plug recall. Your engineer should see the engine ASAP before Honda do any work. The engineer can help present your case in the case of a Dept Fair trading small claims hearing. As soon as the guy rocks up the Honda guys will stop the bullshit and get a proper assesment on their side. You may be able to get the NRMA, AA or RACV, RACQ involved depending on which Aus state you reside.


Good luck.

Chris,

 

the guy said that cylinder 2 is the first to get affected from low oil. they told me that the lack of oil means that the piston and cylinder aren't getting enough lubrication and its just metal on metal.

the funny thing is that last friday the oil was low and was topped up. I drive all weekend no problem then sunday night i get home and notice the tapping noise.

I'm going to wait and see what honda propose in regards to fixing, they said they might be able to organise a 'half half' where myself and them chip in half each. I'll see what they say and what the reason was for the damage and then call in my own independent guy.

 

Does anyone know which cylinder is last to get the oil????
isn't it #4??

 

Huh? They all get oil at the same time. It's #4 that's farthest from the incoming coolant and may run just a tad bit hotter than the others.

 

well these geezers are telling me that cylinder 2 is the last to recieve oil out of the 4 cylinders.

what is the truth to this?

 

You have one oiljet spray nozzle under each piston. They all squirt at the same time once the galley is filled and it takes a second or two after a cold start for it to fill. I'm not seeing how any one cylinder is "last".

 

The guy should really pull the engine down to look at the bearings and pistons skirts before coming to any conclusions.

The bores are lubricated by the oil that spins out from the crank, and oil from bore squirters on the underside of pistons. I build race engines based on Toyota motors and sometimes remove bore squirters due to skirt/squirter clearance problems, or in some cases change to blocks with no squirters at all. The squirters do help keep the piston cooler as they squirt directly on the underside of the piston. The cooling of the bore squirters is only really needed for sustained high load work such as high speed cruising or racing. For day to day driving the splash oil will be enough. The F20C has a history of piston/bore overheats with the revised oil squirter options so its probably more sensitive than other motors. If your engine was raced by the previous owner there could be some existing damage. Best option is to pull the piston/rod under the supervision of a independent engineer. If the pistons skirts and bores are black this is a sign of overheating/rubbing. It there are just sharp scores the cause is more likely to be due to spark plug debris getting stuck down the sides of the piston crown. You may even find some of the ceramic insulator imbedded in there.

The spark plug insulator damage will be a cause of the problem rather than a symptom of an oil problem. Ask the guy if he can explain the spark plug disintegration.

To answer your question, after the oil filter/cooler the oil enters a gallery in the block between cylinders 1 and 2. This gallery supplies the head, crank and bore squirters through lots of small passages. The bore squirter for cylinder number 2 is pretty much the closest thing to where the oil is pumped into the block so will have the best supply. Number 4 if at the end of the gallery so you would expect it to be at the end of the slight pressure gradient along the gallery.

If there is an oil pressure problem it will show up on the rod bearings. If the rod bearings are in good condition there is not an oil supply problem.