FML... I'm done for now with sr's and maybe 240's - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

moses · 05-24-2010, 01:31 AM

This is the second time I rebuild an sr and the third time it shit out on me. I don't even know if I want to rebuild another sr. I was suppose to drive half way across America with this motor and it made it a quarter mile. For those who don't remember my first rebuild was after my turbo FODed out so I did headgasket and cams. Then I killed my #1 cylinder with detonation as shown in the pic.

I found out that my fuel pump did not have enough voltage at full boost after thing else checked good so I hard wired it. Then after fully rebuilding it, I broke it in 500 soft miles and ran it at 15lbs (stock boost for actuator) after and everything went good and checked good the night before. I warm up the car for a 2000 mile drive the next day and down the road it shuts off.
I find

then

that little bump is the piston pin! Yeah destroyed! I don't want to fix it right now, I just want to know how it happened? I think spun bearing but I really don't know what that involves. It's not detonation like the first time because it's not melted, it's just in a bunch of big pieces. Y?

sectorjeff · 05-24-2010, 02:05 AM

Damn dude that sucks. At least drop a bone stock ka just for your dd

Ceepo · 05-24-2010, 02:06 AM

yeah, throw a ka in there and redo the sr slowly

shiftdrift · 05-24-2010, 02:08 AM

or build a ka-t....just saying.

mmdb · 05-24-2010, 02:13 AM

wouldn't have that problem with a LSx v8 :B Keep at it and learn from what happened. It'll serve you a lot in the future. Good luck.

Slammed Assassin · 05-24-2010, 03:00 AM

that sucks bro.. just keep on going and dont give up..try a different route.

spools420a · 05-24-2010, 03:11 AM

dude what makes you think that the second time wasnt detonation?or even pre ignition

1. you have a sark plug thats near disinigrated

2. you have a hole in your piston with a broken wrist pin

3. last rebuild you melted a piston

um whats your setup?I bet this could have been prevented with a wideband and a cheap $300 water/meth injection but again whats your setup you do have some serious heat issues.(detonation/pre ignition is my bet)

moses · 05-24-2010, 08:56 AM

I don't think it was detonation because the spark plug is not melted off like the other time. I don't know if you can see it but the part that curves out on the plug is smashed in and the ring is black from running rich. There is also pieces chuncked off in the cylinder and I can not seem to move the motor at all. I'll pop the head off later to see what really happened but it looks like the piston slamed into the spark plug and valves but I don't know how or why that happens.

fcdrifter20 · 05-24-2010, 11:05 AM

did you change those wrist pins out when you rebuilt it?

jspaeth · 05-24-2010, 11:43 AM

I did a ton of research these weekend on spark plugs.

I know A LOT of people run the BKR7E....but that plug is ISO spec, meaning the distance from the seating surface to the tip of the top is about 4 mm or so shorter than a JIS spec plug, which our cars are SUPPOSED to run. Some people have experienced poor contact with the coilpacks due to this....

I am not sure (I doubt it) if this conributed, but next time go with a JIS spec plug.

The relevant part number is

BCPR7ES-11 (Stock number 1095)....they come gapped at 0.044 so you have to close that down a bit.

Also, the BKR7E is a v-power tip.

As far as I know, ALL of the V-power tip NGK plugs are ISO length....sucks....

moses · 05-24-2010, 02:04 PM

Of course I changed those pins.

And coil packs not hitting the spark plug would cause the opposite of detonation and exploding piston. Good info tho. You should make sure that's in sr FAQ

***S14DB*** · 05-24-2010, 02:26 PM

AFR doesn't cause detonation. Timing Does.

It doesn't matter that you were running pig rich. If you like that spark off to early that's more fuel that is burning as that cylinder is flying up.

You aren't melting shit, you're blowing shit up.

slider2828 · 05-24-2010, 02:33 PM

Interesting, but I never had a problem..... How about Iridiums? EIX plugs? I just checked mine these weekend and they were perfect...

AND S14DB Speaks the TROOF!!!

Quote:

Originally Posted by jspaeth

I did a ton of research these weekend on spark plugs.

I know A LOT of people run the BKR7E....but that plug is ISO spec, meaning the distance from the seating surface to the tip of the top is about 4 mm or so shorter than a JIS spec plug, which our cars are SUPPOSED to run. Some people have experienced poor contact with the coilpacks due to this....

I am not sure (I doubt it) if this conributed, but next time go with a JIS spec plug.

The relevant part number is

BCPR7ES-11 (Stock number 1095)....they come gapped at 0.044 so you have to close that down a bit.

Also, the BKR7E is a v-power tip.

As far as I know, ALL of the V-power tip NGK plugs are ISO length....sucks....

racepar1 · 05-24-2010, 02:39 PM

Quote:

Originally Posted by S14DB

AFR doesn't cause detonation. Timing Does.

It doesn't matter that you were running pig rich. If you like that spark off to early that's more fuel that is burning as that cylinder is flying up.

You aren't melting shit, you're blowing shit up.

A lean mixture can cause detonation or "pinging" just the same as timing can. Ever gotten some bad gas? It pings like shit... A lean mixture is almost certainly what happened to the first piston pictured. Timing can't do that. Lean = heat, heat = melted shit. I also seriously doubt that it was timing that caused his latest failure as well. I suspect either an oiling issue or incorrect clearences related to that piston caused it. The way the piston came apart it looks like it seized in the bore and the rod smashed it's way through it.

*DALAZ_68* · 05-24-2010, 03:12 PM

in other words...he should have his engine built for him...not by him...

***S14DB*** · 05-24-2010, 03:14 PM

Quote:

Originally Posted by racepar1

A lean mixture can cause detonation or "pinging" just the same as timing can. Ever gotten some bad gas? It pings like shit... A lean mixture is almost certainly what happened to the first piston pictured. Timing can't do that. Lean = heat, heat = melted shit. I also seriously doubt that it was timing that caused his latest failure as well. I suspect either an oiling issue or incorrect clearences related to that piston caused it. The way the piston came apart it looks like it seized in the bore and the rod smashed it's way through it.

Lean mixture melting shit is different then detonation.

Bad gas you describe is low octane or resistance to detonation. Not the air:fuel ratio. Bad gas doesn't change the A:F ratio.

I am not saying his damage was caused by detonation or running lean or both. I am saying that his statement that you can't detonate while running rich is false.

moses · 05-24-2010, 04:14 PM

Ok ok thanks for info. Learn something new every day. I ran about 100 miles with timing off but there was no boost. I fixed it and drove 400 miles. Can it be timing if it happen in one cylinder?

And I had a shop build the short block, I did the rest. It does sound like racepar1 is right about the piston getting stuck. How could it be oil tho if the piston got stuck?

jspaeth · 05-24-2010, 05:37 PM

Quote:

Originally Posted by moses

Can it be timing if it happen in one cylinder?

Of course! One cylinder has to fail before the others...the odds of all 4 going out at once is like infinitely low

jr_ss · 05-24-2010, 07:04 PM

Quote:

Originally Posted by moses

And I had a shop build the short block, I did the rest. It does sound like racepar1 is right about the piston getting stuck. How could it be oil tho if the piston got stuck?

If the piston got stuck, that should be a machine shop issue. Then again, you've driven on it for 500miles, so perhaps there is an oiling issue. Siezed shit usually means lack of lubrication.

moses · 05-24-2010, 08:10 PM

I did not know that about timing. But if the piston got stuck in the cylinder then where would the oil not be getting thru? Would a spun bearing do it?

g35gabby · 05-24-2010, 08:17 PM

Quote:

Originally Posted by moses

I did not know that about timing. But if the piston got stuck in the cylinder then where would the oil not be getting thru? Would a spun bearing do it?

sounds like you slapped this car together without understanding alot of things..... no wonder it is in the shape it is.

j20accord00 · 05-24-2010, 08:50 PM

^ lmao this should get good

moses · 05-24-2010, 09:51 PM

Because I didn't know all the aspects of how a engine can break down I shouldn't have built a motor. Haha, I'm not going to get into it online.

bb4_96 · 05-25-2010, 05:32 AM

Have you pulled the bottom end apart yet. I'd kinda like to know what actually caused the problem.

GripTerror · 05-25-2010, 06:32 AM

or you could go ls1 and make as much power with stock reliability and easy plug and play power gainers.

rex2sx · 05-25-2010, 06:51 AM

well i have a 3 pistons from my SR20DET..so if you want 1..just let me know

The same thing happened to my friends BMW, we looked down and saw the wrist...but he over revved his motor so..

dreamin240sx · 05-25-2010, 06:54 AM

sounds like u have a bad case of "i have no idea what i'm doing"

jspaeth · 05-25-2010, 07:58 AM

Quote:

Originally Posted by GripTerror

or you could go ls1 and make as much power with stock reliability and easy plug and play power gainers.

Some people enjoy the process of building a quality motor that is efficient for it's displacement.

Others take the easy route and slap in a SHITTY, INEFFICIENT 6 or 7 liter motor that only produces 50 hp/L. :ghey:

GripTerror · 05-25-2010, 09:13 AM

And some people are clueless idiots example above

400whp and 30mpg on the highway with no turbos and something called torque and a powerband = win

You COULD spend countless thousands on a small displacement motor and push it to its limits and blow it up over and over again spend countless thousands on tuning and so on.... just to reach 400whp... OR you could spend a lil extra to begin with on a nice reliable 400whp+ with TORQUE (aka power) and a power band that's not in the sky but that gets moving from the get go... and not have to blow shit up. Whatever floats your boat.

And your ignorant ass it's 5.7liter for a ls1, it's 6liter for an ls2 and 7liter for an ls7 which produces 500bhp~ that's actually not too shabby considering a 2liter sr requires a turbo to make close to 200bhp.

I rather have a newer fire breathing v8 than a junkyard japan sr motor. The SR is not the be all end all motor.

I rather have a 4G63 than an SR but unfrotunately it doesnt go in a 240.

rex2sx · 05-25-2010, 09:35 AM

Quote:

Originally Posted by GripTerror

400whp and 30mpg on the highway with no turbos and something called torque and a powerband = win

And your ignorant ass it's 5.7liter for a ls1, it's 6liter for an ls2 and 7liter for an ls7 which produces 500bhp~ that's actually not too shabby considering a 2liter sr requires a turbo to make close to 200bhp.

I rather have a newer fire breathing v8 than a junkyard japan sr motor. The SR is not the be all end all motor.
.

I was going to say something about his statement but i let it go. The Ls1 weighs how more than an SR..about 100lbs IIRC, and it has twice the cylinders..i didnt want to turn this into another "XXX motor is better" thread.

So people make CRAZY assumptions. At any rate LS1 FTW

05-24-2010, 02:06 AM	#3
Ceepo Nissanaholic! Join Date: Jan 2008 Location: Cedar City, Utah Posts: 2,007 Trader Rating: (9) Rides Gallery: Ceepo Feedback Score: 9 reviews	yeah, throw a ka in there and redo the sr slowly __________________ TW: http://zilvia.net/f/cars-sale/390459...d9s-coils.html

05-24-2010, 02:13 AM	#5
mmdb Zilvia FREAK! Join Date: Apr 2003 Location: 240sx Posts: 1,558 Trader Rating: (20) Feedback Score: 20 reviews	wouldn't have that problem with a LSx v8 :B Keep at it and learn from what happened. It'll serve you a lot in the future. Good luck. __________________ .25 till 3

05-24-2010, 03:00 AM	#6
Slammed Assassin Nissanaholic! Join Date: Feb 2007 Location: Oxnard/SV Posts: 2,065 Trader Rating: (34) Feedback Score: 34 reviews	that sucks bro.. just keep on going and dont give up..try a different route. __________________

05-24-2010, 08:56 AM	#8
moses Zilvia Junkie Join Date: Mar 2005 Location: Jacksonville, ar Age: 38 Posts: 555 Trader Rating: (2) Rides Gallery: moses Feedback Score: 2 reviews	I don't think it was detonation because the spark plug is not melted off like the other time. I don't know if you can see it but the part that curves out on the plug is smashed in and the ring is black from running rich. There is also pieces chuncked off in the cylinder and I can not seem to move the motor at all. I'll pop the head off later to see what really happened but it looks like the piston slamed into the spark plug and valves but I don't know how or why that happens. __________________ Thats what I said

05-24-2010, 11:43 AM	#10
jspaeth Nissanaholic! Join Date: Mar 2006 Location: Philadelphia suburbs Age: 40 Posts: 2,347 Trader Rating: (7) Rides Gallery: jspaeth Feedback Score: 7 reviews	I did a ton of research these weekend on spark plugs. I know A LOT of people run the BKR7E....but that plug is ISO spec, meaning the distance from the seating surface to the tip of the top is about 4 mm or so shorter than a JIS spec plug, which our cars are SUPPOSED to run. Some people have experienced poor contact with the coilpacks due to this.... I am not sure (I doubt it) if this conributed, but next time go with a JIS spec plug. The relevant part number is BCPR7ES-11 (Stock number 1095)....they come gapped at 0.044 so you have to close that down a bit. Also, the BKR7E is a v-power tip. As far as I know, ALL of the V-power tip NGK plugs are ISO length....sucks.... __________________ Daily driven

05-24-2010, 01:31 AM	#1
moses Zilvia Junkie Join Date: Mar 2005 Location: Jacksonville, ar Age: 38 Posts: 555 Trader Rating: (2) Rides Gallery: moses Feedback Score: 2 reviews	FML... I'm done for now with sr's and maybe 240's This is the second time I rebuild an sr and the third time it shit out on me. I don't even know if I want to rebuild another sr. I was suppose to drive half way across America with this motor and it made it a quarter mile. For those who don't remember my first rebuild was after my turbo FODed out so I did headgasket and cams. Then I killed my #1 cylinder with detonation as shown in the pic. I found out that my fuel pump did not have enough voltage at full boost after thing else checked good so I hard wired it. Then after fully rebuilding it, I broke it in 500 soft miles and ran it at 15lbs (stock boost for actuator) after and everything went good and checked good the night before. I warm up the car for a 2000 mile drive the next day and down the road it shuts off. I find then that little bump is the piston pin! Yeah destroyed! I don't want to fix it right now, I just want to know how it happened? I think spun bearing but I really don't know what that involves. It's not detonation like the first time because it's not melted, it's just in a bunch of big pieces. Y? __________________ Thats what I said

05-24-2010, 02:05 AM	#2
sectorjeff Leaky Injector Join Date: Feb 2010 Location: CA(661) Posts: 83 Trader Rating: (0) Feedback Score: 0 reviews	Damn dude that sucks. At least drop a bone stock ka just for your dd

05-24-2010, 02:08 AM	#4
shiftdrift Nissanaholic! Join Date: Nov 2009 Location: indiana Age: 34 Posts: 2,242 Trader Rating: (42) Feedback Score: 42 reviews	or build a ka-t....just saying.

05-24-2010, 03:11 AM	#7
spools420a Zilvia Junkie Join Date: Dec 2009 Location: phoenix az Age: 43 Posts: 460 Trader Rating: (1) Feedback Score: 1 reviews	dude what makes you think that the second time wasnt detonation?or even pre ignition 1. you have a sark plug thats near disinigrated 2. you have a hole in your piston with a broken wrist pin 3. last rebuild you melted a piston um whats your setup?I bet this could have been prevented with a wideband and a cheap $300 water/meth injection but again whats your setup you do have some serious heat issues.(detonation/pre ignition is my bet)

05-24-2010, 11:05 AM	#9
fcdrifter20 Post Whore! Join Date: Nov 2007 Location: riverside, ca Age: 37 Posts: 2,869 Trader Rating: (44) Feedback Score: 44 reviews	did you change those wrist pins out when you rebuilt it?

05-24-2010, 02:04 PM	#11
moses Zilvia Junkie Join Date: Mar 2005 Location: Jacksonville, ar Age: 38 Posts: 555 Trader Rating: (2) Rides Gallery: moses Feedback Score: 2 reviews	Of course I changed those pins. And coil packs not hitting the spark plug would cause the opposite of detonation and exploding piston. Good info tho. You should make sure that's in sr FAQ __________________ Thats what I said

05-24-2010, 02:26 PM	#12
*S14DB* AFC #1 Join Date: Oct 2003 Location: 昨晩あなたのお母さんの家 Posts: 20,181 Trader Rating: (3) Feedback Score: 3 reviews	AFR doesn't cause detonation. Timing Does. It doesn't matter that you were running pig rich. If you like that spark off to early that's more fuel that is burning as that cylinder is flying up. You aren't melting shit, you're blowing shit up. __________________ Comments should be taken as Opinions not as Statements of Fact

05-24-2010, 03:12 PM	#15
DALAZ_68 not giving a fuck Join Date: Apr 2007 Location: Los angeles Age: 38 Posts: 15,077 Trader Rating: (104) Feedback Score: 104 reviews	in other words...he should have his engine built for him...not by him... __________________ LOL 240... whats better than 1? 5 1's ...lol PSN & XBL GT : Wh0pp3r68 CLUB LEXUS : Wh0pp3r

05-24-2010, 04:14 PM	#17
moses Zilvia Junkie Join Date: Mar 2005 Location: Jacksonville, ar Age: 38 Posts: 555 Trader Rating: (2) Rides Gallery: moses Feedback Score: 2 reviews	Ok ok thanks for info. Learn something new every day. I ran about 100 miles with timing off but there was no boost. I fixed it and drove 400 miles. Can it be timing if it happen in one cylinder? And I had a shop build the short block, I did the rest. It does sound like racepar1 is right about the piston getting stuck. How could it be oil tho if the piston got stuck? __________________ Thats what I said

05-24-2010, 08:10 PM	#20
moses Zilvia Junkie Join Date: Mar 2005 Location: Jacksonville, ar Age: 38 Posts: 555 Trader Rating: (2) Rides Gallery: moses Feedback Score: 2 reviews	I did not know that about timing. But if the piston got stuck in the cylinder then where would the oil not be getting thru? Would a spun bearing do it? __________________ Thats what I said

05-24-2010, 08:50 PM	#22
j20accord00 Zilvia Addict Join Date: Oct 2006 Location: SEASIDE PARK, NJ Age: 39 Posts: 720 Trader Rating: (4) Feedback Score: 4 reviews	^ lmao this should get good __________________ 92 Coupe ka-t

05-24-2010, 09:51 PM	#23
moses Zilvia Junkie Join Date: Mar 2005 Location: Jacksonville, ar Age: 38 Posts: 555 Trader Rating: (2) Rides Gallery: moses Feedback Score: 2 reviews	Because I didn't know all the aspects of how a engine can break down I shouldn't have built a motor. Haha, I'm not going to get into it online. __________________ Thats what I said

05-25-2010, 05:32 AM	#24
bb4_96 Zilvia Addict Join Date: Jan 2006 Location: Under my car Posts: 785 Trader Rating: (4) Feedback Score: 4 reviews	Have you pulled the bottom end apart yet. I'd kinda like to know what actually caused the problem.

05-25-2010, 06:32 AM	#25
GripTerror Zilvia Addict Join Date: Nov 2009 Location: Canada Age: 40 Posts: 685 Trader Rating: (0) Feedback Score: 0 reviews	or you could go ls1 and make as much power with stock reliability and easy plug and play power gainers.

05-25-2010, 06:51 AM	#26
rex2sx Zilvia Member Join Date: Feb 2009 Location: pennsylvania Age: 34 Posts: 158 Trader Rating: (0) Feedback Score: 0 reviews	well i have a 3 pistons from my SR20DET..so if you want 1..just let me know The same thing happened to my friends BMW, we looked down and saw the wrist...but he over revved his motor so.. __________________ SR20DET RDTOP Cylinder Head FS

05-25-2010, 06:54 AM	#27
dreamin240sx Zilvia Junkie Join Date: Aug 2009 Location: west virginia Age: 33 Posts: 531 Trader Rating: (2) Feedback Score: 2 reviews	sounds like u have a bad case of "i have no idea what i'm doing" __________________ RB POWA!!!!!!!!

05-25-2010, 09:13 AM	#29
GripTerror Zilvia Addict Join Date: Nov 2009 Location: Canada Age: 40 Posts: 685 Trader Rating: (0) Feedback Score: 0 reviews	And some people are clueless idiots example above 400whp and 30mpg on the highway with no turbos and something called torque and a powerband = win You COULD spend countless thousands on a small displacement motor and push it to its limits and blow it up over and over again spend countless thousands on tuning and so on.... just to reach 400whp... OR you could spend a lil extra to begin with on a nice reliable 400whp+ with TORQUE (aka power) and a power band that's not in the sky but that gets moving from the get go... and not have to blow shit up. Whatever floats your boat. And your ignorant ass it's 5.7liter for a ls1, it's 6liter for an ls2 and 7liter for an ls7 which produces 500bhp~ that's actually not too shabby considering a 2liter sr requires a turbo to make close to 200bhp. I rather have a newer fire breathing v8 than a junkyard japan sr motor. The SR is not the be all end all motor. I rather have a 4G63 than an SR but unfrotunately it doesnt go in a 240.