Honda / Acura K20a K24a Engine Forum banner

21 - 40 of 42 Posts

·
Registered
Joined
·
253 Posts
No, just clean it if salvageable. If you want be 100% sure, count the needles in a surviving needle bearing and could the ones from the broken ones you found across the engine. No need to change the oil pump tensioner if it still is springy and not worn.
 

·
Registered
Joined
·
27 Posts
Discussion Starter #23
I pulled the head from the block today.
Everything looks great.. I can see marks in the small amounts of carbon on top of pistons 2 and 3 where they made valve contact but i dont see anything on 1 and 4 so I should be dealing with 8 valves at the most Im hoping. I turned the motor over a few times with the head off and the cylinder walls look brand new. Everything including the pistons is very very clean.
 

·
Registered
Joined
·
27 Posts
Discussion Starter #25
Awesome, depending on the market, either replace & refresh the valves or get an other head.
Going to drop it off at a qualified machine shop on Monday. I am a technician at the local Honda dealership and thats where we send all of our heads for cleaning/inspection/valve guides etc. We have been sending k24 heads out like crazy to get seals and guides replaced and occasionally the odd valve. I think the k24 and my k20a are very similar. I will replace all the bad valves with genuine Honda K20A2 valves which I am sure are the same as the K20a valves. I will also replace any guides/seals they say are no good. The last one we sent out at work only took 2 days. I am pretty sure I have the only K20A in the city I live in. The closest one I know of is a couple hours drive away so sourcing a new head isn't really an option,
 

·
Registered
Joined
·
27 Posts
Discussion Starter #27
The machine shop called me this afternoon. He said all 16 valves are bent and need to be replaced. Some guides and seals need to be replaced as well. Hes going to do everything needed and it should be ready in the next couple of weeks. Seems like lots of damage.. more than i expected. I really hope all is good when this is all back together and hopefully running again.
 

·
Registered
Joined
·
27 Posts
Discussion Starter #28
Finally got my head back with 16 new valves, new seals and guides. I got a new OEM head gasket so I am not ready to start putting the engine back together! :)
 

·
Registered
Joined
·
253 Posts
and remember to put the crank pulley bolt on exactly as described in the workshop manual. If a shop does it, print them a copy of the relevant page with the instructions showing torque and where oil has to put on the bolt and washer before the install.
 

·
Registered
Joined
·
27 Posts
Discussion Starter #30
You are just referring to the part where you put new engine oil on the threads/washer then torque to 35 then an additional 90 degrees right? As far as the timing gear pin/key and the crank pulley key there is only one way to install correct? I put the oil pump chain and timing gear back together over a month ago I am wondering if I should take it back apart and re-check it. I should have the head back on the block tonight or tomorrow morning. I still need to rebuild the rocker assembly. I am going to use the complete rocker assembly from the original engine that completely blew up as well as the cams from that engine. The cams are a bit scuffed on two lobes from when the two roller rockers shattered on the newer engine so that's why I am going to avoid them.
 

·
Registered
Joined
·
253 Posts
No, I was referring to the bolt of the crank pulley.
These are tightened just by torque.

The incorrect fitment of this bolt caused all your issues in first place.
 

·
Registered
Joined
·
27 Posts
Discussion Starter #33
I am pretty sure the guy at the machine shop used the wrong valves in my head? I have the head back on with the cams and everything installed. It is timed perfectly and after turning it over a few times the cam marks and all the chain marks line up perfectly. When I turn it over with a ratchet i can hear/feel air coming out of the exhaust side of each cylinder on the compression stroke...
 

·
Registered
Joined
·
27 Posts
Discussion Starter #34
I just flipped the engine on its side so the exhaust ports are facing up. I filled the ports with oil on number 1 cylinder and turned the engine over with a ratchet. As soon as the piston started coming up for the compression stroke the oil bubbled on the timing chain side valve seat. I repeated this process for all cylinders and the timing chain side valve is leaking on every cylinder exhaust side except #4 is making compression.. so it appears the guy at the machine shop put the wrong valves in the head... how the hell do you manage that? Or could there be something else I'm missing?
 

·
Registered
Joined
·
144 Posts
When you say valve clearance are you referring to valve lash? This is easy to check if you have a set of feeler gauges.

Also, are you sure you're not on the exhaust stroke when you feel air?
 

·
Registered
Joined
·
253 Posts
A small amount of leakage is normal. Proper test is a leak down test. Post the numbers here and the pressure used.

Replacing guides and valves needs special machines that can cut the valve seats after honing the guides without realignment. If not, the valve seat plane is not perfectly orthogonal to the valve guide axis.
 

·
Registered
Joined
·
27 Posts
Discussion Starter #37
I know everything was timed correctly. I work as a technician at a Honda dealership and we do VTC actuators and timing chains on K24s all the time so I'm very familiar with this process. I just pulled the head again and when shining a light at the valve seats (piston side) you can see a large amount of light in the exhaust ports. The intake valves aren't seated properly either but not nearly as bad as the exhaust. No wonder I have no compression.
The shop I brought it to has been doing this for 30+ years and i have had a few heads rebuilt there in the past without issue... Not sure what happened. Is there something special about K20A valves vs. A2? I will be bringing the head back in the morning.
 

·
Registered
Joined
·
156 Posts
Just read through your saga. What a nightmare. Here's hoping the shop fixes it. Hard to see how they could not check the valves were seated before sending it out - what a mess!
 

·
Registered
Joined
·
27 Posts
Discussion Starter #39
Just read through your saga. What a nightmare. Here's hoping the shop fixes it. Hard to see how they could not check the valves were seated before sending it out - what a mess!
What a nightmare indeed.
I was going to bring it back to the original machine shop that messed up but he was closed yesterday when I went to drop it off for some reason. I decided I would bring it to another shop. The shop I brought it to this time does every single head rebuild we do at work. We've sent 4 heads to him in the last month or so and hes NEVER had an issue rebuilding our heads. The reason I didn't originally bring it to this shop is because they were on holidays at the time (closed). He said the other guy probably didn't lap the valves correctly but he may have over ground the valves/seats and if that's the case he may need to change valves/seats AGAIN. He said at minimum I'll be at least another $300 into it depending if it needs any new parts. SO in the end this head rebuild is costing me around $1000 when it should have been 500 max.:oops: Better run good when its done!
 

·
Registered
Joined
·
27 Posts
Discussion Starter #40
Got the head back from the new machine shop Installed on block - everything good now! :)
Engine is almost all buttoned up now... oil pan sealed, timing cover sealed, just needs accessories/intake then its ready for the car. :)
 
21 - 40 of 42 Posts
Top