S000M

Had a bad day at the track. An intake valve seat for #1 cylinder let go and beat up the piston and head a little bit. 8k ago I had all 4 cylinders resleeved and the head rebuilt with new valves, guides, dual coil springs using Ferrea componets and 4 new JE pistons. This was after broken valve in #2. Engine has been running great until this. The # 4 piston got a couple chunks in it too. Cylinder walls are fine. And the new springs & valves look fine, but I'll let the machine shop determine that when I either repair or place the head itself.

So I have engine torn down & the cylinder head removed. Is it possible to remove and replace pistons from below? I plan to reuse the oem connecting rods as I did before. (after remove subframe cross brace, drop the oil pan then oil pump baffle). In other words disconnect the connecting rods on 1 & 2 from below then push out top and reinstall new pistons from top and reconnect rods from below? Trying to avoid complete engine tear down again if feasable. I also had the crank polished and balanced, new bearings and such when I had it out before. (Found a great machine shop). I have a feeling the answer is no but it never hurts to ask. I imagine someone has tried this before. My main concern here is the oil pump assy interfearing with access to #1.

Thanks

almost forgot: 2003 AP1 with 102,000 miles.

yamahaSHO

That's how it is done... Remove rod bolts/nuts from bottom and remove the piston and rod from the top. Remove retaining clip, push out wrist pin, and swap the pistons while reversing the process.

osoquik

Exactly! Do it from the top like yamahaSHO stated. On a 4g63t the crank, oil pump & etc. would need to be removed before dropping the pistons/rods from below (extra work for just swapping pistons). I assume it's a similar process on a f20/22.

Side note: yamahaSHO saw you're in Omaha, NE

S000M

That is music to my ears. I will certainly give it a go. Since these are new rings ( 8k mi), and assuming no hidden damage, I plan to carefully mark location of each ring and reuse on new pistons and avoid break-in time. I think it should work. If you or anybody else has suggestions please chime in.

yamahaSHO

Unfortunately.

osoquik

PM'd

postman

If you dropped a valve seat I don't see how its possible all your valves are OK?

S000M

Like I said they look fine, but I have not disassembled any of the valves themselves yet for close inspection. I don't have a tool for that yet. I have a good reliable machine shop guy. He totally rebuilt the valve head assembly for cylinder # 2 a year ago when I actually broke an oem valve inside the cylinder causing much worse damage than the seat did this time. That's when I had the valve train beefed up a little, resleeved cylinders and new pistons, brass guides, s/s valves and dual coil springs. The engine ran great, 8 & 9k rpm at track all the time. His repair work still looks like new, just unfortunate occurance on valve seat which I understand is not unusual for a Honda to do now & then. I may just let him check out all the valves & guides when he repairs head. I trust him.

S000M

For General Information: I was successful at removing all four pistons. Access to #1 piston requires a little repositioning of crank shaft in order to work around the oil pump but not a problem. All rings appear to be ok except the top ring on #1 got compressed a little and stuck in the piston. I'm hoping I can replace just that one ring and avoid a lengthy break-in after repairs. My machine shop expert will check all rods and make sure nothing bent or broken. probably replace the connecting rod bearings while at it. The crank is ok except for a slight shadow line on #3 which I can easily polish it out..can't feel it. So now it's in hands of my machinest to repair or replace what's necessary. May end up replacing all 4 pistons as well. Decided to splurge & replace OEM headers w/Invidia's and maybe gain a couple ponies but loose some weight for sure.

Anyway, thanks for the helpful replies.