I had been having a little ticking noise from the engine couple weeks ago. The noise eventually got louder. Last night during my trip to my friend's shop, the ticking noise became metal banging metal. I could feel the very strong vibration from the clutch pedal. When I got to my friend's shop, we took the shield between the tranny and the engine off and found that the flywheel was loose. So we thought the flywheel bolts had backed out. Well, today my friend continued to take the tranny out to see if it was really the flywheel bolts. To his surprise, he saw this.











BTW, this is a rebuilt H22A4 motor in Prelude SH. The place where the crankshaft broke was the place where I had spun the bearing on (therefore, the motor rebuilt) last year. Due to some damages caused by the spun bearing, we had the crankshaft ground. My friend double checked the roundness and used undersized bearing for this. Now it broke. Has anyone seen this happened before?

Just a little more info on the rebuilt motor, it has about 10k mile since the rebuilt. It has seen 3 track days, 2 National Tours, 1 Pro-Solo, and 6 weekends of auto-x since the rebuilt. So I don't know if the excess stress may have something to do with this. Now I'm looking for a good used one or to buy a new one. What to do???

 

Wow... I have yet to see a crank broken like that.

 

Lol reminds me of my old sohc engine.
Hope you find a replacement bro.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by B6tPoweredMx3 &raquo;</TD></TR><TR><TD CLASS="quote">Lol reminds me of my old sohc engine.
Hope you find a replacement bro. </TD></TR></TABLE>

So you had this failure before? Did you find out how it broke?

 

WOW Vincent! That is pretty amazing. Could have been a fracture from the pounding the crank saw before the build.

 

i had always heard to not have honda cranks ground because they would lose their structural integrity. Again this is what I was told, not 100% sure.

 

I'm thinking it could be that the place who groundd the crank didn't leave enough radius on the crank rod journals and that is where the stress started. Is it standard procedure to have the crank shot peen and heat treated after grinding? Or it could be the crank has an internal fracture already when the bearing spun before the rebuild? Any thoughts?

Charleston


Modified by CivicFerio at 5:02 PM 6/23/2005

 

Wow - that's pretty gruesome.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2000BoostedEX &raquo;</TD></TR><TR><TD CLASS="quote">i had always heard to not have honda cranks ground because they would lose their structural integrity. Again this is what I was told, not 100% sure.</TD></TR></TABLE>
Although, I've heard of a similar situation happening to a technician I used to work with. He was a bit shady, but I guess this reconfirms it. Once they're machined, they lose their surface hardness. Can anyone elaborate on this? I'm interested...

 

Honda cranks are nitrided I believe, and machining removes that nitride coating.

 

Well this was on my old 1.6 sohc mazda engine, but my best guess was that the woodruff key walked out on me at about 6k rpms. And that it put so much stress on the outside part of the crank that it snapped it off.

 

holy crap ive never seen a picture of that before. thats incredible, thats like the strongest part of a block. You can fix it, just take it to a machine shop, they can weld it back. Or if you wanna save some cash, goto a muffler shop.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by turbo_b16_ex &raquo;</TD></TR><TR><TD CLASS="quote">You can fix it, just take it to a machine shop, they can weld it back. Or if you wanna save some cash, goto a muffler shop.</TD></TR></TABLE>

I hope you're joking!!!

 

holy crap.......never seen that before!

 

What did the motor build consist of? Those are some nice rods

 

Wow....tore it right in two.

I cant even fathom the force it would take to tear a forged crank like that.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by vwong &raquo;</TD></TR><TR><TD CLASS="quote">

I hope you're joking!!! </TD></TR></TABLE>


Of course he is. Everyone knows JB weld is the way to go.

 

yea a little bit of jb weld and some duct tape and youll be set.

 

jeez!!!!! could of been worst. Good luck bro.