H23A1 Knocking - Honda Prelude Forum

mcnos · 11-25-2010, 01:15 AM

I'm thinking its a headgasket but im not sure

Been sitting for 3 years and now back to life.
Compression came 200 200 185 225, but if i do a compression test again, the numbers come up differently. Hearing slight knocking but not sure if its normal. Slight white smoke still, no milky coolant. oil and gas tank cleaned and refilled.

After turning the car off and listening in the engine bay, air sounds like its escaping from somewhere and theres slight oil all over the tranny.

and I have slight carbon build-up.

Cracked head gasket or can it be something else?

It drives fine but the knocking worries me.

If anyone can help that would be nice.

1996 lude si · 11-26-2010, 11:49 AM

I'm guessing you probably have a bad bottom end...spun a rod bearing or main bearing... had the same thing with my prelude... couldn't really figure out where the knock was coming from and then my motor seized up. Probably buy a new motor or rebuild it...i'm guessing the motor is toast

mcnos · 11-29-2010, 09:05 PM

Quote:

Originally Posted by 1996 lude si

I'm guessing you probably have a bad bottom end...spun a rod bearing or main bearing... had the same thing with my prelude... couldn't really figure out where the knock was coming from and then my motor seized up. Probably buy a new motor or rebuild it...i'm guessing the motor is toast

Well I talked to my brother who previously owned it, and he said it was the rod bearing, but thats not causing the sound is it? might be for the white smoke yeah

1996 lude si · 11-30-2010, 09:45 AM

does the sound sound like its coming from the top end in the timing area? because that's where mine was coming from and i thought maybe it was the top end but it ended up to be a bottom end. is you're oil pressure light blinking? does the noise only happen when its idling or all the time?

mcnos · 11-30-2010, 05:54 PM

Quote:

Originally Posted by 1996 lude si

does the sound sound like its coming from the top end in the timing area? because that's where mine was coming from and i thought maybe it was the top end but it ended up to be a bottom end. is you're oil pressure light blinking? does the noise only happen when its idling or all the time?

The sound sounds like its coming from below the head and top of the block but idk for sure, can't specify the sound even with a sound test. noise happens all the time and the oil light is blinking as well

minilogoguy18 · 12-01-2010, 07:47 AM

More than likely a spun bearing, the gap created by the excessive clearance is your rod smacking the crank.

1996 lude si · 12-01-2010, 09:50 AM

yup exactly what he's saying and i'm going to have to say part of it is going to be you're oil pump is junk b/c thats directly below the head under the timing cover... and thats where the oil light reads everything i believe... going to have to say its time for a COMPLETE rebuild... just a matter of time until the bottom end seizes up! you're having the Same problem i had with my h23a

mcnos · 12-01-2010, 09:05 PM

well the weird thing is it was rebuilt

is it possible to replace the rod bearings by taking of the oil pan and doing it that way? someone told me I can

mcnos · 12-01-2010, 09:05 PM

well the weird thing is it was rebuilt

is it possible to replace the rod bearings by taking of the oil pan and doing it that way? someone told me I can

minilogoguy18 · 12-02-2010, 07:06 AM

Yeah I have seen someone do it that way but the problem is your crank, it probably needs to be turned, just putting over sized bearings in it is like putting a band aid on it and it will more than likely spin those. A guy I work with tried to do that for a customer with a S2K who didn't have the money to do it right and it spun the bearings again not long after.

1996 lude si · 12-02-2010, 09:21 AM

Personally I would buy a whole new crank kit with main and rod bearings... but its going to depend on how bad you're block is damaged. just w/e u do DONT buy a jdm motor from JDM engine depot

westbank23 · 12-02-2010, 04:22 PM

Quote:

Originally Posted by 1996 lude si

Personally I would buy a whole new crank kit with main and rod bearings... but its going to depend on how bad you're block is damaged. just w/e u do DONT buy a jdm motor from JDM engine depot

^^ why not?just curious

1996 lude si · 12-02-2010, 04:59 PM

b/c of the nightmare that i'm dealing with them now about getting a motor i never put in the car and it was internally damaged when i got it... if u wanna know more read this forum about my problems with them... Sioux Falls Racing • View topic - Has anyone dealt with JDM Engine Depot

minilogoguy18 · 12-02-2010, 06:20 PM

^And you are wrong about the oil pump. The sending unit on the back center of the block just above the oil pan reads pressure/level not the pump itself. The pump is on the bottom of the block too btw, not directly below the head, and if it were bad he'd get a flashing oil light, be careful not to misinform.

1996 lude si · 12-03-2010, 08:23 AM

Quote:

Originally Posted by mcnos

The sound sounds like its coming from below the head and top of the block but idk for sure, can't specify the sound even with a sound test. noise happens all the time and the oil light is blinking as well

obviously you didn't read what he wrote... and didn't mean to misinform considering the oil pump is still in the timing area and i know where it is...

mcnos · 12-06-2010, 03:21 PM

Well now I took off the oil pan, find the rod bearings slightly moveable, and found metal shavings inside the pan, asking what could that posssibly be besides rod bearings

minilogoguy18 · 12-06-2010, 06:15 PM

How were the main bearings? The metal shavings are more than likely from the rod bearings. Also never said anything about oil all over the tranny, that's the distributor o-ring, that thing can make a nasty leak if not changed when it starts.