New rebuild, low compression on #3 cyl.
 

About 1000 miles on a rebuilt D16A6 I wanted to check my C/R so we checked with a gauge to get 181, 180, 160, 180. After some oil was poured in the compression read 180.The piston and rings are new and the block was bored .20 over. My question is what is most likely the cause for the leak. ???

Re: New rebuild, low compression on #3 cyl.
 

how is the head did you get it machined? re-torque the head...you got a new head gasket right?

Re: New rebuild, low compression on #3 cyl.
 

Yeah, thanks for responding. The head was milled and the headgasket is new also. I ordered a new set of rings Im gonna pull the piston and inspect the rings and replace them if needed. Its possible they are not seating properly.

Re: New rebuild, low compression on #3 cyl.
 

maybe that one didnt seat or you broke a ring putting them in.. i dont thing that happened though i would think the compression would be lower.

did you use honda rings?

mine arent exactly even either. 200 200 200 210. good enough for me on my new rebuild though, like i give a ---- about 10psi..lol

Re: New rebuild, low compression on #3 cyl.
 

It's only a 12.2% difference which is still within spec. (someone correct me here, but isn't it a 20% difference?) I wouldn't worry about it.

Re: New rebuild, low compression on #3 cyl.
 

Yes, I believe you are correct. a Honda Tech told me about the 20% variance. I may be a bit of a perfectionist, but Im blowing swoke like a pig. Im gonna pull the piston today and inspect the rings. I bought a spare set just in case they are the problem. im not using Honda brand rings, Im using Top Line brand pistons and rings. Im hoping the block isnt warped.

Re: New rebuild, low compression on #3 cyl.
 

You also want to make sure that all the gaps in the rings are in different angles when put on the piston.

Re: New rebuild, low compression on #3 cyl.
 

yeah did you position the rings correctly?

Re: New rebuild, low compression on #3 cyl.
 

I havent pulled the piston out yet, but, bore looks mint. The diagnosis of the rings gaps not being positioned properly seems very probable. Ill find out fur shure soon enough.
The A6 gasket was starting to deteriorate where it allowed coolant to flow by.( I can post pics if anyone is having a similar problem) this is the possible cause for the oil residue in my coolant catch tank. I rec'd my ARP bolts, and Im gonna put the Z6 metal gasket torqued to 60lbs as per ARP instructions.
I also noticed how the rocker arm bolts were not torqued to specs. The head was rebuilt about 500 miles ago and they seemingly loosened up. Is this a common problem? Im gonna re-torque them but I cannot see why they wont loosen up again. Has any one torqued them over manufacturer specs, or used Loc- Tite? ???
Any how after about 6mos. of gathering parts I am ready to do the install after the compression leak is repaired. I really couldnt have done it W/O HMT. Thanks Nogs.
Oh yeah, Ill post pics fer ya when all is done. :y

Re: New rebuild, low compression on #3 cyl.
 

not an error when using comp. tester :P? how did you break in the motor? how about vlave lash?