kc7

Does anyone has bad experience of doing head & block skimming on your hondas before changing to new head gasket (top overhaul)? Can you share in this thread.

I have a Honda Accord 2.0 (soch non-Vtec). Had a blown gasket and mechanic recommend top overhaul but require skimming on the cylinder head as it was warped. 3 days after job done, the gasket is blown again but luckily i realize it before temperature meter rise. This time, i take the car to another guy who said the engine block is warp and likely that the previous mechanic did not check its surface before installing the new gasket. He then recommend to skim the head cylinder again and also skim the engine block. This is to allow a good mating surface for the gasket to sit on it and seal up the entire surface.

I'm not sure at this stage, whether to go ahead with the skimming as i heard some say its not worth doing skimming on a warped block as it will lead to bigger problem later on. Not to mention i paid big bucks previously for a shitty job.

Please advise.

GhostAccord

To have the head milled (Skimmed) a touch more and the block decked (Skimmed) is a regular process if the mounting surfaces are warped and still within Honda's machining specifications.

Ask your mechanic if he has the specs for the F20 deck height and head height limits. It is OK to have this procedure done as long as it does not exceed Honda's specs for your engine.

This procedure will also bump up the compression of the motor a bit and your timing may have to be adjusted a wee bit due to the shorter deck height. Depending on how much is taken off both surfaces. Not a real big deal.

Do you know how much the head has been milled already?

kc7

Thanks for replying Ghost. I really have no idea how much material has been milled off. I bought the car last year and its 13 yrs old. Previous owner could also have milled it before. Anyway, the mechanic is not doing the milling himself but has to send it to some machine workshop to do it. I hv to hope and pray that they know what they are doing.

About adjusting the timing, do you mean adjusting the distributor? Should I go for more +ve or more -ve? Does increasing compression also increase the risk of pre-detonation. Will using a colder plug helps?

GhostAccord

Timing and compression increase all depends on how much they have to remove from the block to straiten it out. If they only have to remove enough that the block and head will still be within spec you shouldn't have any problems with detonation (compression being too high) and timing can probably be adjusted with the distributor as you mentioned.

Ask the machine shop how much they removed and see if you can get a thicker head gasket to make up the difference. Then you will have nothing to worry about.

kc7

Finally, got the car back today. I notice it's difficult to get the engine started after the overhaul job. Now the engine crank for about 2-3 sec and then stopped. I have to turn the ignition key again to make it crank. There is a 50% chance that each cranking will stop after 2-3 sec (the other 50% it will crank continuously until engine come alive).

The mechanic told me that the ignition timing has been adjusted to original setting and distributor was adjusted correctly. I felt the car has lost some power overall and throttle has poor response between 1 to 2.5k rpm. Any idea what happened?

Whats Up DOHC

Damn for all that $$$ you could have got a lower mileage motor. Somethin to consider for the future

kc7

Agree, the amt i spent is enough to get a used 2.2 Vtec soch + installation. But my car is running on natural gas, so a 2.0 is a better option in terms of cost and ease of tuning.

Anyway, I send it to another place to check today and it was a great relief for me when the guy discovered a tool left behind in the air intake hose (just before the air filter). Guess this cause obstruction in the air flow and in turn power lost. Took it out and problem solved. I hope they didn't leave more **** like this inside the engine.

AnDoxia

Wow, at least ya got a free tool out of it. Props on the nat gas, nice.