Ok, guys. I promised pics and boy do I have pics. First I'm going to put the facts and then I'll put what my mechanic thinks and what I think happened. Take into consideration I had been running 9PSI for a long time. I had run 14PSI for like 2 months and failure occured when trying to up the boost to 18PSI. I was still running the 9PSI maps I had setup on the dyno caused I forgot to include more fuel for protection... yes you can hit me for that.
First of all, once we took out the engine we saw holes on both sides of the block on rods #2 and #4.
There is also a hole on the right side of rod #1, which actually removed the alternator base from the block so the alternator was hanging.
The left side does not look good either.
My main concern was the head. So I was real anxious to get it off. At first site, when we removed the valve cover, it looked ok. No signs of problems.
The timing kit was also ok. Meaning that at least the crank and cams kept turning in sync. Lucky me since I had them replaced brand new from my last rebuild.
Once we got the head off first thing we looked at was the pistons. Pistons 1 through 3 looked ok. Piston #4 looked like it contacted water.
Pistons #1 & 2
Pistons #3 & 4
Under further inspection, the gasket had given way between cylinder #4 and a water passage causing water to get into the cylinder. None the less, the car did not smoke nor did it consume water before that night, cause I check the radiator level just before going out for testing.
So now onto the head. When looking at the face of the head you can see all valves look ok but cylinder #4 looks a bit too white, meaning possible lean conditions. Also, under further inspection we saw contact @ pistons #2. The same evidence can be seen on the piston:
We are going to test all the valves later to see if they are still sealing.
Some of the miscelaneous bits and pieces found. On the oil pan you can see a piece of the main bearing cap (center of pic) and the top part of the rod #2 end.
The bottom part of the rod or rod cap #2 was found on the highway...
Now from the oil pan pics you can see water in the oil. But looking at the main bearings I don't see any evidence of water induced problems:
Main bearings #1 & 2:
Main bearing #3:
Main bearing #4:
Ok. so rods #1 and #3 came out clean. Rod end #4 was still on the crank and it could still be moved easily by hand so it was not stuck to the crank. Rod #2... well as I said before the rod cap was found on the highway. The top part of the rod end was found in the oil pan. And the crank looked hitted or impacted on rod bearing #2.
Rod #1, 3 looks the same:
Rod end #4:
Rod bearing #2:
And wrapping up... this is what pistons #2 and #4 looked like. It does not need to be said that the rod was almost welded into the wrist pin and could not be moved by hand.
Now onto the subjective part of this post. My mechanic believes that the water entering cylinder #4 caused the rod to fail. I on the other hand believe that if this was so then the rod end should be stuck to the crank or something. The water should have caused bearing failure and this caused rod failure? Am I way off? Also, as I said, the car was not consuming water before that night so maybe the gasket failed when I was testing @ 16PSI with ****ty fuel maps (rookie mistake). I still believe that me not adjusting the fuel maps caused detonation. Maybe this caused the rod bolts on rod #2 or the rod itself to fail and pieces of rod #2 caused rod #4 to break in two. My mechanic did say the other bolts looked worned out. By the way, this were stock rods on stock bolts.
What do you engine gurus think?
CSI: 240sx (not 56k safe)
Argh, another one.
Well again like mine, I am leaning away from thinking the cause was detonation. The piston tops look pretty good, ring lands from what I can see look decent as well. How do the spark plugs look? Serious, rod destroying detonation should leave some significant damage on the piston tops and ring lands, and usually destroys spark plug tips. I dont see any of that damage.
Hydrolocking is a definite possability. At high amounts of boost it takes only a VERY small amount of water in the cyl to cause hydrolocking. Coolant in the oil is not really a telling factor at this point though, as things tend to get mixed up inside the shortblock once holes are bieng made and things are breaking haha.
Weird that you only had failure on that one rod, and it bent so badly. It looks almost as if the bearing siezed. Where did you have your engine assembled? If I were you I would have the wreckage checked out by a good machine shop guy, not just a regular mechanic. See what he says.
Sorry to see that man. Are you planning on rebuilding?
Well again like mine, I am leaning away from thinking the cause was detonation. The piston tops look pretty good, ring lands from what I can see look decent as well. How do the spark plugs look? Serious, rod destroying detonation should leave some significant damage on the piston tops and ring lands, and usually destroys spark plug tips. I dont see any of that damage.
Hydrolocking is a definite possability. At high amounts of boost it takes only a VERY small amount of water in the cyl to cause hydrolocking. Coolant in the oil is not really a telling factor at this point though, as things tend to get mixed up inside the shortblock once holes are bieng made and things are breaking haha.
Weird that you only had failure on that one rod, and it bent so badly. It looks almost as if the bearing siezed. Where did you have your engine assembled? If I were you I would have the wreckage checked out by a good machine shop guy, not just a regular mechanic. See what he says.
Sorry to see that man. Are you planning on rebuilding?
Re: (fiznat)
The only pic i have of the plugs is the one from the head. But they looked ok. Maybe a bit white but no physical damage. The ring lands on every cylinder look ok. The only phisycal damage i could find was was the piston skirts where the rods made contact.
Hydrolocking is a possiblity but I still think rod #2 went out first, although I can't be sure. Rod end #4 was not locked or anything, it spun freely enough by hand. I'll try and have my mechanic send the pieces to the machine shop... but I don't think they are going to say much about it. Third world country... ****ty machine shops. So my mechanic's opinion is probably the best I have.
But the crank where rod bearings #2 sit looks ok. Does not seem to have seized. Just the impact damage on the sides.
Now, if hydrolocking was the culprit it was caused by the gasket leak on cylinder #4. What the hell could have caused this? My mechanic thinks maybe chamber temps got too high on cylinder #4 making the head warp and thus the gasket gave way. This would point to my fuel maps again But I was using ARP head bolts, if that means anything.
Of course I'll be rebuilding... unless somebody buys my car as it is. What would it look like if I encouraged you to rebuild when you blew up the engine and when I blow mine I ran away?
Hydrolocking is a possiblity but I still think rod #2 went out first, although I can't be sure. Rod end #4 was not locked or anything, it spun freely enough by hand. I'll try and have my mechanic send the pieces to the machine shop... but I don't think they are going to say much about it. Third world country... ****ty machine shops. So my mechanic's opinion is probably the best I have.
But the crank where rod bearings #2 sit looks ok. Does not seem to have seized. Just the impact damage on the sides.
Now, if hydrolocking was the culprit it was caused by the gasket leak on cylinder #4. What the hell could have caused this? My mechanic thinks maybe chamber temps got too high on cylinder #4 making the head warp and thus the gasket gave way. This would point to my fuel maps again But I was using ARP head bolts, if that means anything.
Of course I'll be rebuilding... unless somebody buys my car as it is. What would it look like if I encouraged you to rebuild when you blew up the engine and when I blow mine I ran away?
Re: (turtl631)
Eastmost county of San Jose, right next to San Pedro. And since this is a small country it takes like 30min to drive from one side to the other of SJ.turtl631 wrote:Hm, I hope you're able to figure it out. I don't have much tech info to offer, but we have to keep plugging away with the KA-Ts. Slightly OT...where is Curridabat? Is that part of San Jose? I'm gonna be in San Pedro for about a month.
Re: (Kenrik)
Ahhh....another one bites the dust!
This is crazy how many rod failures there have been in the past month...
Also, were you running forged pistons? From the pics it looks like you were...
Good luck with everything man, me, fiznat, virus, etc etc know exactly what you're going through...
This is crazy how many rod failures there have been in the past month...
Also, were you running forged pistons? From the pics it looks like you were...
Good luck with everything man, me, fiznat, virus, etc etc know exactly what you're going through...
Re: (mirra32)
Too freaking difficult/expensive to even consider it. I just live with the downtimes when **** happens.mirra32 wrote:so here is my though about ka-t....go for it but have an extra block or two for when it blows.....i hate seeing this stuff...makes my stomach hurt thinking i'll be going turbo soon......
Re: (Kenrik)
Stock bottom end should be good to 300WHP. Add forged pistons... I'll say 350WHP. More than that and it's pushing it.Kenrik wrote:Keep in mind that he was going for 18PSI that's over 400WHP on stock rods? From what I have been reading on these forums things start to break if your running stock over 300WHP right?
Re: (MarkEmark)
Yes. Ross 8.5 .020 over from KA24DE.com. Those things rock. Probably going to go with those again and a set of Pauters also from ka24de.com.MarkEmark wrote:Also, were you running forged pistons? From the pics it looks like you were...
Re: (turtl631)
All tuner magz here suck big time. Wouldn't be caught dead on them... plus they just go for the show car look. Not my style.turtl631 wrote:Try to get it featured in TicoTuner when its back together! On a serious note, do you get taxed on all the parts you import?
Yes we do. Anywhere from 30-50% from the receipt price + shipping (WTF?). It all depends on how the customs guy wants to call the part. But I have my ways of going around them....
Re: (erollinc)
Depends on the size of your turbo. On a T3/T4E, yes. It also depends on your mods. It's better to set the limits on WHP.erollinc wrote:wouldnt it be safe to assume that any boost in upwards of 15psi deserves some forged rods? i mena isnt this like motor#4?
good luck with the rebuild