Changing piston rings - advice

[mctagart]

My car has started developing signs of blowby, i am getting exhaust vapour throuh my breather and a bit of oil.

I compression tested it and and cylinder 3 is down to 120psi where as the rest are 179.

http://youtu.be/87J3eKxsE_w

I am gonna pull it apart with the hope its just a cracked ringland, as i had been having problems with boost spiking and i thnk it fucked my bloody piston/ring, i am hoping that my cylinder wall is ok and hasnt been damaged

My question is that i can do it with my engine still in the car cant i, i dont want to take it out as i only put the bloody thing in back in August.

Has anyone replaced just the rings before?

Its fairly expensive as its gonna cost £180 in parts just to change the rings by the time you factor in taking the head off with HG and bolts. People have been saying while i am doing it i should change all the shells, but again its when do you stop!

 

[buckets]

most likey the piston ring lands ,100 percent

 

[starletburkie]

do it once do it right mate

 

[weeJohn]

You might need to rehone the block but there is a chance the honing is still good and wont need to be done. The head needs to come off anyway so you could pull it and the sump off, take #3 out and see what you have. Pistons wont come out the bottom, can only come out the top. If you are on the stock mani and its not ported there is a good chance the pistons rings are cracked.

 

[mctagart]

yes pulling it apart tomorrow, its on a an uprated mani so dont think that was the problem. Lets hope no damage!!

Its the gold EP70 sleeper in the mebers garage