Sr20det crank not spinning freely after build - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Vicious Beaner! · 11-25-2019, 10:19 AM

What's up guys . Got a sr20det built last year by a shop. Engine ran fan before stock but decided to build to get to 450 to 500 reliably with a gtx3076r . Did pistons, rods , new all ARP hardware. The whole 9. Tried to get it going last week with a tuner etc . Did the proper break in procedures and that crank wont really budge. Spins maybe a 1/4 turn by hand and then just stops. . Engine ran for 10 seconds and shut off. Drained the oil and no shavings . Undid the trans , starter etc and still hard to turn by hand with a 2 foot breaker bar. So yanked the engine out and having another shop take a look at what's wrong . Is it possible for that engine to be complete crap?
I'd appreciate any feed back or similar related issues.

Sent from my SM-N960U using Tapatalk

Turbosauce74 · 11-25-2019, 10:37 AM

Was the crank polished or machined? Sounds to me like your mains could be too tight of tolerance.

Sent from my SM-G965W using Tapatalk

Vicious Beaner! · 11-25-2019, 10:49 AM

Quote:

Originally Posted by Turbosauce74

Was the crank polished or machined? Sounds to me like your mains could be too tight of tolerance.

Sent from my SM-G965W using Tapatalk

Yea from my understanding builder did say it was machined and polished. That's what I was thinking aswell . Hopefully it isn't anything major. That would be a bummer

Sent from my SM-N960U using Tapatalk

PoorMans180SX · 11-25-2019, 10:56 AM

Yep, sounds like the mains were too tight. If you're lucky it'll just require a polish on the crank and resetting the main clearance. If you're unlucky they did some wonky machining and the engine will need a line hone and a new crank.

Turbosauce74 · 11-25-2019, 11:19 AM

Quote:

Originally Posted by Vicious Beaner!

Yea from my understanding builder did say it was machined and polished. That's what I was thinking aswell . Hopefully it isn't anything major. That would be a bummer

Sent from my SM-N960U using Tapatalk

Luckily you might not need to pull too much apart, a bit of plastigauge and you could check each bearing individually. I'm assuming you didn't get the block line bored?

Sent from my SM-G965W using Tapatalk

*brndck* · 11-25-2019, 01:40 PM

Pull the spark plugs and make sure the cylinders aren’t full of fuel.

I bought a car that the previous owner said wouldn’t run, turns out he replaced the injectors but there was an old oring stuck in the fuel rail causing raw fuel to fill cyl 2. It would crank about 2 revolutions then stop dead.

ultimateirving · 11-26-2019, 10:34 AM

Quote:

Originally Posted by brndck

Pull the spark plugs and make sure the cylinders aren’t full of fuel.

I bought a car that the previous owner said wouldn’t run, turns out he replaced the injectors but there was an old oring stuck in the fuel rail causing raw fuel to fill cyl 2. It would crank about 2 revolutions then stop dead.

This shit happened on my car too. Started her up and she was idling then just died after about 15 seconds and wouldnt crank any more. Took off the fuel rail and fuel was everywhere.

jedi03 · 11-26-2019, 12:39 PM

if nothing in cylinders, check with bore o scope that nothing has contacted piston and see if spins freely, if doesn't check timing too before pulling motor apart

RalliartRsX · 11-26-2019, 01:06 PM

1) Either the main clearances are too tight (which is why you ALWAYS spin the crank by hand once you bolt up the mains and after every conrod install)
2) Piston to valve contact

Confirm if they align honed when they rebuilt the engine if using stock main bolts. If using aftermarket make sure they align hone correctly and have them issue you the spec sheet before and after align hone. If they did it incorrectly, the engine will have to be torn down.

And make sure they also give you always the measurement bearing clearances and which bearings they used (mains and rod bearings)

[email protected] · 11-26-2019, 02:01 PM

is someone seriously recommending plastigauge? lol
crank bearing clearances could have possibly been too tight. tear it apart and if it only ran for 10 sec. your crank could be ok. Get a new shop to redo the whole bottom end.

S14rebuild · 11-26-2019, 03:16 PM

Quote:

Originally Posted by [email protected]

is someone seriously recommending plastigauge? lol
crank bearing clearances could have possibly been too tight. tear it apart and if it only ran for 10 sec. your crank could be ok. Get a new shop to redo the whole bottom end.

Whats wrong with plastigauge? Yes are there better tools to.check measurements?

But plastigauge is a very useful tool and many if not thousands of motors have been built using it and ran perfectly

jedi03 · 11-27-2019, 11:57 AM

there are just better ways of doing things...

*brndck* · 11-27-2019, 01:24 PM

Quote:

Originally Posted by jedi03

there are just better ways of doing things...

imo plastigauge is a great tool to use to make sure someone didn't put the decimal in the wrong spot when trying to use a dial caliper.

i'm still amazed at how many people can't properly use one, but claim to be engine builders.

RalliartRsX · 11-27-2019, 01:55 PM

Nothing wrong with plastigauge for a DIY to double check.

However, youtube mechanics who have no idea how to use their $800 dial calipers need something to blame......

Vicious Beaner! · 11-27-2019, 04:37 PM

Ended up taking it to another shop so they can tear it down and check everything .I have a feeling he didnt line hone since they were Arp main studs and or tight clearances. Just found out hes known for leaving tight clearances through another customer smh.

Vicious Beaner! · 11-27-2019, 08:41 PM

Sooo look what I found guys . Head and cams are shot. Smh. Crank spins smoothly still after head is off. So it was the head all along

Sent from my SM-N960U using Tapatalk

S14rebuild · 11-27-2019, 09:59 PM

Holy fuk, after seeing that nightmare, id pull the bottom end apart and check EVERYTHING

Vicious Beaner! · 11-27-2019, 10:33 PM

Oh bottom end coming apart forsure to get inspected. Damn it I'm deep into this sr20 already smh lol

Kingtal0n · 11-30-2019, 08:55 AM

you would notice something like that during installation

which means those parts went in looking fine

which means they were ruined within that 10 second time frame

which means they were installed without any oil (my guess)

Turbosauce74 · 11-30-2019, 09:58 AM

Quote:

Originally Posted by [email protected]

is someone seriously recommending plastigauge? lol
crank bearing clearances could have possibly been too tight. tear it apart and if it only ran for 10 sec. your crank could be ok. Get a new shop to redo the whole bottom end.

Boy do you look wrong now....

Sent from my SM-G965W using Tapatalk

Turbosauce74 · 11-30-2019, 10:01 AM

Quote:

Originally Posted by Vicious Beaner!

Sooo look what I found guys . Head and cams are shot. Smh. Crank spins smoothly still after head is off. So it was the head all along
Sent from my SM-N960U using Tapatalk

Glad to see the bottom end most likely survived, but yeah I'd be pulling it apart and checking every oil galley for shavings. What cams are those?

Sent from my SM-G965W using Tapatalk

RalliartRsX · 11-30-2019, 10:29 AM

Quote:

Originally Posted by Kingtal0n

you would notice something like that during installation

which means those parts went in looking fine

which means they were ruined within that 10 second time frame

which means they were installed without any oil (my guess)

I am leaning this direction. However, the photo with the cam cracked right at the cam gear seems like the shop installed the cam caps with a 500lb torque wrench as it looks like a fracture vs a fatigue (no oil) failure.

*brndck* · 11-30-2019, 06:42 PM

JEEZUS FUCK.
Dude that sucks.

Looks no oil pressure was getting to the head.
Why the cam cracked I don’t know, but FUCK.

Turbosauce74 · 11-30-2019, 06:45 PM

Possibility that the caps were over torqued or the cam shaft was bent. I had a shitty shop drop one of my cam shafts and bend it. Cam would install fine but tough to turn, ended up having to pay for a new set.

Sent from my SM-G965W using Tapatalk

RalliartRsX · 11-30-2019, 06:52 PM

Cams are hardened (brittle). If they are dropped, they shatter, not bend lol

*brndck* · 12-01-2019, 01:48 AM

Quote:

Originally Posted by Turbosauce74

Possibility that the caps were over torqued or the cam shaft was bent. I had a shitty shop drop one of my cam shafts and bend it. Cam would install fine but tough to turn, ended up having to pay for a new set.

On a KA or SR20 if you overtighten the cam caps, you’ll pull the threads out. Seen it quite a few times when people don’t pay attention to the part where it says INCH/pounds, not FOOT/pounds.

Also yeah I’ve never seen a cam bend. They crack.

crazyorigin · 12-01-2019, 08:40 AM

Quote:

Originally Posted by RalliartRsX

Cams are hardened (brittle). If they are dropped, they shatter, not bend lol

Cams can certainly bend. The hardening on iron camshafts does make them brittle but as long as they are they will easily bend. The can chip or have a piece break off that is partially due to hardening and also partially due to the metal characteristics of iron. The hardening is also just case hardening, meaning roughly the outer .020" of their surface is much harder than the rest. They are not made of carbide...

jedi03 · 12-02-2019, 09:29 AM

I would reach out to the original shop and have them pay for fixing it...sry to see that...

nick_d_240sx · 12-03-2019, 02:10 PM

Anytime an engine is rebuilt or the cams/cam gears or timing chain/belt has been removed, turn over the engine by hand multiple times to verify everything is spinning smoothly.

Sorry man.

Vicious Beaner! · 12-03-2019, 07:59 PM

Yea engine is getting completely overhauled fellas/ladies . Had shavings in the pan. Reached out to the original builder and he is dodging me. Had to buy a new head , get it machined and of course tear had the engine tore down to fully inspect any further damage smh. Would it be right or wrong to put the shop out on blast with these pictures I have to save someone else's engine in the future?

11-25-2019, 10:19 AM	#1
Vicious Beaner! Zilvia FREAK! Join Date: Oct 2009 Location: Moreno valley/ Riverside Ca Posts: 1,498 Trader Rating: (38) Feedback Score: 38 reviews	Sr20det crank not spinning freely after build What's up guys . Got a sr20det built last year by a shop. Engine ran fan before stock but decided to build to get to 450 to 500 reliably with a gtx3076r . Did pistons, rods , new all ARP hardware. The whole 9. Tried to get it going last week with a tuner etc . Did the proper break in procedures and that crank wont really budge. Spins maybe a 1/4 turn by hand and then just stops. . Engine ran for 10 seconds and shut off. Drained the oil and no shavings . Undid the trans , starter etc and still hard to turn by hand with a 2 foot breaker bar. So yanked the engine out and having another shop take a look at what's wrong . Is it possible for that engine to be complete crap? I'd appreciate any feed back or similar related issues. Sent from my SM-N960U using Tapatalk

11-25-2019, 10:56 AM	#4
PoorMans180SX Zilvia.net Advertiser Join Date: Nov 2005 Location: Michigan Age: 33 Posts: 5,431 Trader Rating: (16) Rides Gallery: PoorMans180SX Feedback Score: 16 reviews	Yep, sounds like the mains were too tight. If you're lucky it'll just require a polish on the crank and resetting the main clearance. If you're unlucky they did some wonky machining and the engine will need a line hone and a new crank. __________________ Build: http://zilvia.net/f/showthread.php?t=643065 Friends don't let friends buy knock-offs.

12-03-2019, 02:10 PM	#29
nick_d_240sx Leaky Injector Join Date: Dec 2017 Location: Oregon Age: 39 Posts: 64 Trader Rating: (0) Feedback Score: 0 reviews	Anytime an engine is rebuilt or the cams/cam gears or timing chain/belt has been removed, turn over the engine by hand multiple times to verify everything is spinning smoothly. Sorry man. __________________ 1990 240SX SR20DET GTX2863R

Thread Tools
Show Printable Version Email this Page
Display Modes
Linear Mode Switch to Hybrid Mode Switch to Threaded Mode

11-25-2019, 10:37 AM	#2
Turbosauce74 Join Date: Jun 2017 Location: Ab Age: 32 Posts: 34 Trader Rating: (0) Feedback Score: 0 reviews	Was the crank polished or machined? Sounds to me like your mains could be too tight of tolerance. Sent from my SM-G965W using Tapatalk

11-26-2019, 12:39 PM	#8
jedi03 Nissanaholic! Join Date: Jul 2008 Location: albuquerque Posts: 1,786 Trader Rating: (8) Feedback Score: 8 reviews	if nothing in cylinders, check with bore o scope that nothing has contacted piston and see if spins freely, if doesn't check timing too before pulling motor apart

11-26-2019, 01:06 PM	#9
RalliartRsX Post Whore! Join Date: Apr 2006 Location: Maryland Posts: 4,753 Trader Rating: (32) Feedback Score: 32 reviews	1) Either the main clearances are too tight (which is why you ALWAYS spin the crank by hand once you bolt up the mains and after every conrod install) 2) Piston to valve contact Confirm if they align honed when they rebuilt the engine if using stock main bolts. If using aftermarket make sure they align hone correctly and have them issue you the spec sheet before and after align hone. If they did it incorrectly, the engine will have to be torn down. And make sure they also give you always the measurement bearing clearances and which bearings they used (mains and rod bearings)

11-26-2019, 02:01 PM	#10
[email protected] Nissanaholic! Join Date: Jul 2008 Location: Zacatecas, Mx; Paramount, Ca Age: 31 Posts: 1,626 Trader Rating: (32) Feedback Score: 32 reviews	is someone seriously recommending plastigauge? lol crank bearing clearances could have possibly been too tight. tear it apart and if it only ran for 10 sec. your crank could be ok. Get a new shop to redo the whole bottom end.

11-27-2019, 11:57 AM	#12
jedi03 Nissanaholic! Join Date: Jul 2008 Location: albuquerque Posts: 1,786 Trader Rating: (8) Feedback Score: 8 reviews	there are just better ways of doing things...

11-27-2019, 01:55 PM	#14
RalliartRsX Post Whore! Join Date: Apr 2006 Location: Maryland Posts: 4,753 Trader Rating: (32) Feedback Score: 32 reviews	Nothing wrong with plastigauge for a DIY to double check. However, youtube mechanics who have no idea how to use their $800 dial calipers need something to blame......

11-27-2019, 04:37 PM	#15
Vicious Beaner! Zilvia FREAK! Join Date: Oct 2009 Location: Moreno valley/ Riverside Ca Posts: 1,498 Trader Rating: (38) Feedback Score: 38 reviews	Ended up taking it to another shop so they can tear it down and check everything .I have a feeling he didnt line hone since they were Arp main studs and or tight clearances. Just found out hes known for leaving tight clearances through another customer smh.

11-27-2019, 08:41 PM	#16
Vicious Beaner! Zilvia FREAK! Join Date: Oct 2009 Location: Moreno valley/ Riverside Ca Posts: 1,498 Trader Rating: (38) Feedback Score: 38 reviews	Sooo look what I found guys . Head and cams are shot. Smh. Crank spins smoothly still after head is off. So it was the head all along Sent from my SM-N960U using Tapatalk

11-27-2019, 09:59 PM	#17
S14rebuild BANNED Join Date: May 2019 Location: Florida-FAIL Posts: 2,497 Trader Rating: (8) Feedback Score: 8 reviews	Holy fuk, after seeing that nightmare, id pull the bottom end apart and check EVERYTHING

11-27-2019, 10:33 PM	#18
Vicious Beaner! Zilvia FREAK! Join Date: Oct 2009 Location: Moreno valley/ Riverside Ca Posts: 1,498 Trader Rating: (38) Feedback Score: 38 reviews	Oh bottom end coming apart forsure to get inspected. Damn it I'm deep into this sr20 already smh lol

11-30-2019, 08:55 AM	#19
Kingtal0n Post Whore! Join Date: Jul 2005 Location: South Florida Age: 38 Posts: 4,649 Trader Rating: (17) Feedback Score: 17 reviews	you would notice something like that during installation which means those parts went in looking fine which means they were ruined within that 10 second time frame which means they were installed without any oil (my guess)

11-30-2019, 06:45 PM	#24
Turbosauce74 Join Date: Jun 2017 Location: Ab Age: 32 Posts: 34 Trader Rating: (0) Feedback Score: 0 reviews	Possibility that the caps were over torqued or the cam shaft was bent. I had a shitty shop drop one of my cam shafts and bend it. Cam would install fine but tough to turn, ended up having to pay for a new set. Sent from my SM-G965W using Tapatalk

11-30-2019, 06:52 PM	#25
RalliartRsX Post Whore! Join Date: Apr 2006 Location: Maryland Posts: 4,753 Trader Rating: (32) Feedback Score: 32 reviews	Cams are hardened (brittle). If they are dropped, they shatter, not bend lol

12-02-2019, 09:29 AM	#28
jedi03 Nissanaholic! Join Date: Jul 2008 Location: albuquerque Posts: 1,786 Trader Rating: (8) Feedback Score: 8 reviews	I would reach out to the original shop and have them pay for fixing it...sry to see that...

12-03-2019, 07:59 PM	#30
Vicious Beaner! Zilvia FREAK! Join Date: Oct 2009 Location: Moreno valley/ Riverside Ca Posts: 1,498 Trader Rating: (38) Feedback Score: 38 reviews	Yea engine is getting completely overhauled fellas/ladies . Had shavings in the pan. Reached out to the original builder and he is dodging me. Had to buy a new head , get it machined and of course tear had the engine tore down to fully inspect any further damage smh. Would it be right or wrong to put the shop out on blast with these pictures I have to save someone else's engine in the future?