2kblueintegra

I burnt a valve on my exhaust side of my b18b ls engine. I brought it to the machine shop and they replaced the burnt valve with new ones and seals pressure tested the head and decked it. When I put the head on I did a leakdown test and my results are not good.

All 4 cylinders have 50% leakage. When I set cylinder 1 to tdc and leakdown air is escaping from cylinder 3! When I set cylinder 2 to tdc and leakdown air escapes from another cylinder...i believe 4....they consistantly change from one to the other as I leakdown each cylinder...

I am not sure what is wrong at this point... I started to perform a valve job last night but only finished two of the 4 cylinders because I ran out of time. I tested each cylinder after the valve job and still same problems...

My best guesses to whats wrong are as follows...but really i have no clue...
I am leaking out of my head gasket
My timing is off
I need to finish my valve job and see whats good

Any suggestions would be very helpful!!!

kyden

you're only supposed to check leakage in the cylinder that is TDC. did you adjust valve lash?

why did you do a valve job after a machine shop fixed the head? i'm not following..

2kblueintegra

I am only checking leakage in the cylinder that is tdc however air is leaking from another cylinder.... sorry I mean i am adjusting valve lash not a valve job...the machine shop did fix the head and the valves....

dev203d

I am 90% sure its ur head gasket, thats how air is getting from one cylinder to another. Unless you have a cracked head but probably not. Check for mayo like stuff under the oil cap, and white smoke from ur muffler and u will be 100% sure that it is it.

2kblueintegra

i dont even have the distributor on yet....and im not starting it unless my leakdown test results get better..... head was pressure tested and checked....no cracks...head was decked and head gasket is new from honda but based on the results it def could be... i really hope not though! im really leaning toward it being a timing issue or valve is open...

dev203d

Ok, time to check all the little things, if its a new head gasket, check to make sure it's installed correctly. Not like backwards or something because there is a direction that they are supposed to go in. After that, check that you have the piston at TDC on the right stroke, not in the intake stroke!! lol i know this sounds like stupid stuff but it could be it! let me know how it goes!

2kblueintegra

many things wrong but number 1 is that my harbor freight leakdown tool was fed up and no matter what every cylinder wether it was tdc or not was 50-60% leakage... returned it for a new one and now im 5-10% leakage on all 4...

racebum

are you 100% sure cam timing is correct? if it isn't you could be creating too much overlap by being off a tooth on one of both cam causing pressure loss. also you're spinning the motor with the starter for results right? spinning by hand or impact is not fast enough to be accurate

dev203d

WTf dude lol im buying a engine lift from them later this week. Never shopped with them before but they better be good!!! 5-10% is normal leak your fine thats because of the gap between the piston ring and the wall, which lets some amounts of air pass through, known as "blow-by". You should be good to go.

2kblueintegra

Your lift should be fine from them. Keep your receipt and your all good... Yes engine is all good now. Thanks for the help...

dev203d

Glad it worked, maybe I'll see around it if I'm in Hartford sometime lol