i just rebuilt my d16a {new rings,bearings and so forth} and did a mini me swap. the car was idiling rough so i did a compression test i was getting 200 lbs in #1&2 185 in#3 and 65 in #4. i adjusted the valves and got #4 up to 90 lbs yesterday before i went to work i was letting the car warm up and it shut off. did another compression test and now i have 0 compression in #3 & 4 and 185 in #2 my question is do you think i screwed up putting the rings in or do you think it could be a head gasket i took the head off today and noticed nothing out of the ordinary it is a 88 crx si some suggestions would be nice thank you i am about to drop the oil pan and pull the #4 piston out and check the rings.

 

Like you said, you did a compression test and below 135 psi i think that is what it is if i can remember correctly is considered below optimal compression. if you are getting a huge fluxuation in compression between cylinders then you have either the rings or a gasket leaking somewhere.

When i did a piston replacement on a b16b2 a while back, an easy way to make sure all your rings are being put under the same conditions is to lube (be generous) the cylinder with clean oil, lube the piston and all rings the same, compress the rings with the ring compressor and assuming that you are going to pull the head off the block, and add oil to the inside of the ring compressor (the top of the piston basically) while inserting the piston in from the top. after the piston is in, move it within the cylinder slowly straight up and down trying not to come to close to the top or bottom of the cylinder, then reconnect the connecting rod to the crankshaft. Remember to lube the journals then assemble.

After you have done all of this to every cylinder, pistons/rings, journals, insert a paper towel into each of the cylinders to help soak up the oil (repeat paper towel application until oil level in the cylinder is minimal) then turn the flywheel by hand to get the inner 2 pistons to TDC. Wipe as much oil as you can from the top of the pistons and repeat the same process for the 2 outer cylinders. Remember, try as hard as possible to avoid getting oil in the cooling jackets or the head threads (if you get fluid in there, you risk cracking the block when torquing the head down so try and get it out if you do).

Assuming you only pull the oil pan off and do all work from the bottom of the engine, do every step i showed except for pouring oil into the top of the ring compressor.

Replace oil (and coolant if you pulled the head) start the engine and run no more than 10 seconds. When started, DO NOT blip the throttle or rev the engine in ANY way, just let it do its thing to get everything settled. Pull the plugs after the short run and do a compression test in all cylinders stating with any cylinder and working your way across the block. 1 to 3 psi difference is acceptable in my books but i think 5 to 7 is considered ok in others. But you should never be getting more than 10 psi otherwise you definately have something wrong but after all of this you can know for sure that it is NOT the rings causing the fluxuations.

If it still does it, check your gasket. When started and you are diagnosing to see if the head gasket is the culprit, you can tell by small "pishing" sounds coming from the gasket seat around where the cylinders should be. If you have a D16, you most likely have a metal head gasket. make sure there is no debris or small pieces of dirt on the gasket seat. If there is, clean them and torque the head down to i think it was 54 ft lbs. Start with the middle head bolts and work your way outward torquing each of them to 22 ft lbs then to the full 54 ft lbs repeating the same bolt pattern movement. An improperly torqued head can cause leakage too.

You can tell for sure with a mechanics stethoscope and narrow in on the problem. Hope this gives a little insight.

 

Thanks for the info. Very helpful and informative.

 

thanks for the help after doing all of that the trouble was in the head the valves are not seating properly

 

That would definately do it. Did you fix the problem yet? If you did, good job. Thats a hard problem to diagnose and repair even if you are present at the time of the problem.

 

i put the stock head back on unitl i can get the vtec head reworked. i checked the head by closing the valves and pouring gas through the intake ports and the exhaust ports and it leaked out through the valves. with the head off.it runs good with the stock head but i would like to get the vtec head back on soon 250.00 to rebuild it at the local machine shop