sr20det knocking sound - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

nicku · 09-25-2007, 12:50 AM

So my friend helped me rebuilt the engine. And after we put it back, the car started right away. when we rev the engine to 2000 rpm, it starts to get the knocking sound. We bleed the lifters already. but the sound didnt go away. it starts at 2k rpm, and as the rpm goes higher, the sound goes faster. it goes away as soon as we let go the throttle. now my friend who is a mechanic started to think its a sign of detenation. But we dont know what cause that. Or anybody has any other idea?

sunnys14 · 09-25-2007, 01:09 AM

i never heard anyone detonating at idle. rod knock? did you install the bearings correctly?

nicku · 09-25-2007, 01:14 AM

it wasnt doing that at idle. at idle it was perfectly fine. Only when I rev to 2k and it started doing that. well...2k to 2500 it starts doing that

Sileighty_85 · 09-25-2007, 07:35 AM

yeah if its knocking only when you rev it and its gets faster through the RPMS then you spun a rod bearing, so id advise you not to start that engine anymore

nicku · 09-25-2007, 11:24 AM

then what am i supposed to do now? take out the engine again?

daryl337 · 09-25-2007, 11:28 AM

yep. Or take the lower and upper pan off... which is just as much work as taking out the engine. At either route, it sounds like the torque specs on your rods were not met.

benefitx · 09-25-2007, 12:03 PM

yep, happened to me.

nicku · 09-25-2007, 12:19 PM

if its the rods, why there was no sound when i idle?

nicku · 09-25-2007, 12:24 PM

will it still be the lifters are bad even though I already bled them?

Sileighty_85 · 09-25-2007, 12:25 PM

well did you have the crank polished and and checked to make sure its straight and with in rebuildable specs?

Did you Mic the bearings to make sure they were the correct size?

Sileighty_85 · 09-25-2007, 12:33 PM

Quote:

Originally Posted by nicku

will it still be the lifters are bad even though I already bled them?

Lifters make Quick "ticking" noises

So if you Engine is making ticking noises then your oil pump crapped itself

09-25-2007, 12:50 AM	#1
nicku Zilvia Junkie Join Date: Aug 2007 Location: St. Cloud, MN Age: 40 Posts: 545 Trader Rating: (0) Feedback Score: 0 reviews	sr20det knocking sound So my friend helped me rebuilt the engine. And after we put it back, the car started right away. when we rev the engine to 2000 rpm, it starts to get the knocking sound. We bleed the lifters already. but the sound didnt go away. it starts at 2k rpm, and as the rpm goes higher, the sound goes faster. it goes away as soon as we let go the throttle. now my friend who is a mechanic started to think its a sign of detenation. But we dont know what cause that. Or anybody has any other idea?

09-25-2007, 07:35 AM	#4
Sileighty_85 Post Whore! Join Date: Dec 2006 Location: Misawa, Japan Posts: 6,815 Trader Rating: (8) Feedback Score: 8 reviews	yeah if its knocking only when you rev it and its gets faster through the RPMS then you spun a rod bearing, so id advise you not to start that engine anymore __________________ 後輪駆動車１番 1989 Built SR GT2871R -363whp 1998 S14 W/RB25- 250ish (For Now) 1986 SR86 - 200ish 1990 R32 GTR - 320hp Don't Buy Engines from JDM-Online http://zilvia.net/f/businesses/207457-jdm-online.html Don't Buy XS-Power or SSAC Shit

09-25-2007, 11:28 AM	#6
daryl337 Zilvia Junkie Join Date: Aug 2005 Location: Pac NW Age: 39 Posts: 589 Trader Rating: (1) Feedback Score: 1 reviews	yep. Or take the lower and upper pan off... which is just as much work as taking out the engine. At either route, it sounds like the torque specs on your rods were not met. __________________ This is my clever and witty signature.

09-25-2007, 12:25 PM	#10
Sileighty_85 Post Whore! Join Date: Dec 2006 Location: Misawa, Japan Posts: 6,815 Trader Rating: (8) Feedback Score: 8 reviews	well did you have the crank polished and and checked to make sure its straight and with in rebuildable specs? Did you Mic the bearings to make sure they were the correct size? __________________ 後輪駆動車１番 1989 Built SR GT2871R -363whp 1998 S14 W/RB25- 250ish (For Now) 1986 SR86 - 200ish 1990 R32 GTR - 320hp Don't Buy Engines from JDM-Online http://zilvia.net/f/businesses/207457-jdm-online.html Don't Buy XS-Power or SSAC Shit

09-25-2007, 01:09 AM	#2
sunnys14 Zilvia FREAK! Join Date: Mar 2006 Location: a land far far away... Posts: 1,549 Trader Rating: (19) Feedback Score: 19 reviews	i never heard anyone detonating at idle. rod knock? did you install the bearings correctly?

09-25-2007, 01:14 AM	#3
nicku Zilvia Junkie Join Date: Aug 2007 Location: St. Cloud, MN Age: 40 Posts: 545 Trader Rating: (0) Feedback Score: 0 reviews	it wasnt doing that at idle. at idle it was perfectly fine. Only when I rev to 2k and it started doing that. well...2k to 2500 it starts doing that

09-25-2007, 11:24 AM	#5
nicku Zilvia Junkie Join Date: Aug 2007 Location: St. Cloud, MN Age: 40 Posts: 545 Trader Rating: (0) Feedback Score: 0 reviews	then what am i supposed to do now? take out the engine again?

09-25-2007, 12:03 PM	#7
benefitx Banned from the Marketplace Join Date: Oct 2006 Location: suwanee ga Posts: 670 Trader Rating: (0) Feedback Score: 0 reviews	yep, happened to me.

09-25-2007, 12:19 PM	#8
nicku Zilvia Junkie Join Date: Aug 2007 Location: St. Cloud, MN Age: 40 Posts: 545 Trader Rating: (0) Feedback Score: 0 reviews	if its the rods, why there was no sound when i idle?

09-25-2007, 12:24 PM	#9
nicku Zilvia Junkie Join Date: Aug 2007 Location: St. Cloud, MN Age: 40 Posts: 545 Trader Rating: (0) Feedback Score: 0 reviews	will it still be the lifters are bad even though I already bled them?