S13 blacktop sr20 picked up cheap. Is it salvageable??

[wyattg96]

I picked up a s13 sr20det last night for practically nothing. Took it home put crank pulley on spins great. Guy I got it from says it had head problems. Got to looking at the tops of the pistons and there's 2 small marks on the intake side of the motor on each piston where it looks like the valve hats hit. The damage doesn't look to bad but would cause this? Over revving and throwing rockers? I have never built and sr or had one ripped apart so this is all new to me. I searched for the past 2 hours and haven't found any good answers or similar situations. The damage on top of the pistons is rather minimal. Quarter of an inch at the worst long and not deep at all. Really just 2 little dings on each piston. Any insight on this?


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

[fliprayzin240sx]

Pictures of the damage?

[street_sleeper]

Yeah if you can get us some pics of the damage that would be great. If you valve stamped your pistons then new parts are going to be required as well as a trip to the machine shop.

[wyattg96]

I will post pics in a few hours when I go to my buddy's garage. I was talking to the guy who runs pavels machine shop/engine building. He told me exhaust guides are very prone on sr motors to go bad.


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

[speedfiend]

Exhaust guides on SR's do tend to wear out pretty bad but that is not going to cause the valve to kiss the piston. Do you know if the head was ever taken off by the previous owner and had work done? Sounds to me, since there is very minimal imprint on the pistons, that the head may have had some work done and they mixed up the shims when putting it back together. If it threw a rocker I would think the imprint would be more severe but it is possible if the rocker didn't hold the valves open very far. The other senerio could be that the timing was not set properly or the chain jumped a tooth due to a bad tensioner or something and caused the valves to hit. Either way you are probably looking at some bent valves, for sure, that will need to be replaced. As for the pistons if it is a very very minor imprint, you could probably get away with reusing them, but you are running a high risk of hot spots developing on the pistons and preignition/detonation which is no good. I would recommend replacing the pistons as well. Just my 2 cents based off the information you have provided. Good luck getting it all buttoned back up.
Cameron

[wyattg96]

Yea I'm guessing timing was not set properly. Guy said he bought it as a running swap and it didn't work out. He didn't seem to know much about it at all. He was a "honda guy". I dis assembled the block today and there's a few bearings with a little wear but all journals were perfect. Bearings are really in good shape overall. I'm going to take the head apart tommorow and check that out. I know of a few shops not too far away I feel comfortable with working on the rwd the app for zilvia won't let me upload any pictures but I am going to replace pistons because I do not want to risk any problems down the road. I appreciate the input! Thanks. Glad everybody on here's not a bunch assholes.


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

[wyattg96]

68452
68453


Sent from my iPhone using Tapatalk (http://tapatalk.com/m?id=1)

[brndck]

yeahhhhh that is NOT "minimal" contact.
i would not use those pistons.
you most likely have bent valves as well.