Nissan 240SX Forums banner
Cancel
Create thread New Garage Forums

SR20DET ran..ran...then died.

Jump to Latest
1 - 20 of 24 Posts
T

tokendog

· Registered
Joined
·
94 Posts
Discussion starter · #1 ·
HI 240sxforums.

I've posted a few times on here but not in a while. I have a 240sx with a SR20DET in it. It blew a HG a while back and I changed it. I used a OEM HG with ARP studs - torqued to specs. The car started right up - had a few grounding issues, sorted those out, and then it had coolant flow issues - sorted that out. It ran for about two days and one day while speeding up to around 3.5k RPM, the RPMs just dropped and the car shut off.

It would not start again. I checked for fuel, good to go. I checked for spark, good to go. I checked the timing - still the same as when it was running. The cams are turning. I have not removed the valve cover to check the camshafts, to see if they are broken or anything, but I did not hear any type of rattling noise or mechanical breakdown when it shut off. It just turned off.

I do not have a diagnostic port on my ECU and my wiring is not perfect(a mechanic did this for me, doubt he knew what he was doing), but it has been running fine up til this point. It most likely is an electrical problem, but I am not experienced enough to know.

Here's a video of the car trying to start up:
http://video.google.com/videoplay?do...15816985&hl=en

I have not done a compression check but that is the next on the list when I get another day off.

Any ideas? I will happilyS send cash to anyone who can help me get this thing up and running again.
 
#2 ·
whow.... to my ear and eye that is spinning WAY to fast, even for a SR20DET

yeah, i'd be doing a compression test asap

personally if i had this i'd be asking myself did i torque the head studs to the correct ft/lbs? could they have backed out? stretched?
 
Discussion starter · #3 ·
I used a good torque wrench and double checked the settings, but I am willing to admit that its possible any where that I made a mistake. I'm a paranoid person though and usually double check every thing, but some thing is wrong and its quite possible I made a mistake.

I'm assuming its likely I will need to redo the HG job.
 
#4 ·
well i'm talking from one of my friends personal experience

he did a HG job on his KA24DE

ran for a day or so, then did what yours did, died and cranked uber' fast. cracked everything open again to see WTF?

turns out that the head studs either stretched or backed out a bit and the engine lost compression on all cylinders. all he did was re-tightened the studs back down to the specs, ran fine [until it hit a wall at a local track]

check compression
 
Discussion starter · #5 ·
So do you think it would be as simple as retorquing the head? The OEM gasket "melts" and forms to the surface. If he used a metal gasket, retorquing it might have worked. With a composite gasket, its possible I may have to redo the head altogether...unless the "stretching" is minor and the gasket is still in tact... I doubt I'd be that lucky.

But what you're saying does make sense. The engine heats up, expands, cools down, contracts...the studs, ARP or not, stretch...compression is lost. I will check compression and check the torque on the studs. I need to make sure the camshafts and lobes are good anyway. I am simply hoping my decision to go with an OEM gasket doesn't bite me on the rear end.

Thanks for the info. :)

P.S. Usually tho the ARP studs need to be retorqued around 1k miles. Most reason ARP studs "fail" is because the installer didn't retorque them at around 1k miles...I barely put 30 miles on the car before it died.
 
#6 ·
yeah his were ARP

idk it's just an idea, worth looking into before you go just ripping the head off

i know how much of a b!tch it is, but just taking out the cams and checking the bolt torque FIRST before pulling the head off completely seems worth the effort
 
#7 ·
Did you use motor oil or moly lube with the arp head studs??? The reason i ask is, arp gives two different sets of torque specs for their studs depending on which one you use when installing them. I have seen many honda engines do the same due to people calling arp and asking for moly lube specs and then using 10w30 instead. This DOES matter greatly.
 
Discussion starter · #8 ·
I used the ARP lube. I will definitely check the torque on the studs. Tearing down my engine isn't a big deal. I like working on my car - especially when I'm motivated by the possibility of finding a solution to fix the problem. I am going to get a compression tester and test the compression first. If its bad, I'll pull the valve cover off and cams, etc. and check the torque on the studs.

From what I know, the SR20DET's main HG issue is head lift during high heat/revs due to weak OEM bolts. The HG is actually pretty good and its recommended to use the ARP studs to eliminate the lift issue. The OEM gasket acts as a good fail safe to keep you from warping your block by blowing out should you overheat. Metal HGs like Apexi on the other hand will not give out and you'll likely warp the block before you know there is a problem...

However in this case it appears, if my thought rational is correct, that I may have made a poor decision. If the ARP studs did allow the head to lift enough to lose compression, it might have damaged the composite HG and now I may have to replace it altogether. If I had of gone with metal, tightening it down would have resealed it and it may have been fine..

I guess I'll find out soon enough. =P
 
Discussion starter · #9 ·
Btw, I torqued it down 75lbs. In increments of course. I used the instructions, but if I remember correctly, it was increments of 50, 70, then 75. Some thing like that. I also tightened it by hand with the hex wrench, then backed it out just a tad to allow for the stud to seat correctly when torqued.
 
Discussion starter · #13 ·
Erscheinung said:
using the wrong lube on the studs, sorry i was distracted by countdown on MSNBC

my comment was late lol
Click to expand...
LOL, yeah I reread the thread and caught on. Nah, I used the ARP lube. I try to do things by the books whenever I can. I took a long time working on this HG job because it was my first time doing this and I wanted to do it right. I researched a lot before I did any thing and made sure it was the proper way to do it. Some thing went wrong and I lack the experience to problem solve it.

I should have taken the car to a "professional" who knew about the engine and had it done right the first time, but I wanted to learn how to work on my own car. I have been scammed by mechanics before so I figured it was a good idea.

I don't have a running car to show for it, but I definitely have learned a lot...so it was worth it. Now if I can get a running car AND the knowledge, I'd be golden. :>
 
#14 ·
Erscheinung said:
using the wrong lube on the studs, sorry i was distracted by countdown on MSNBC

my comment was late lol
Click to expand...

i know from exp. trust me it makes all the difference in the world. My gs-r motor that i sunk almost 8k in had the same issue. I used the moly lube, and the wrong specs and bam, back at square one. I have done many of them before, but on that one, i was in a hurry.
 
#15 ·
tokendog said:
LOL, yeah I reread the thread and caught on. Nah, I used the ARP lube. I try to do things by the books whenever I can. I took a long time working on this HG job because it was my first time doing this and I wanted to do it right. I researched a lot before I did any thing and made sure it was the proper way to do it. Some thing went wrong and I lack the experience to problem solve it.

I should have taken the car to a "professional" who knew about the engine and had it done right the first time, but I wanted to learn how to work on my own car. I have been scammed by mechanics before so I figured it was a good idea.

I don't have a running car to show for it, but I definitely have learned a lot...so it was worth it. Now if I can get a running car AND the knowledge, I'd be golden. :>
Click to expand...
no see that might be the problem, BECAUSE you used the ARP stud lube... there is a SEPARATE set of torque specs that you are SUPPOSED to use because you used their lube

idk ARP is fu@ked up in my opinion

i just use OEM replacement studs whenever i can, unless you're running like insane boost OEM should hold
 
#18 ·
sometimes it is

BUT ceramic HG makes things complicated

if it was metal i'd tell you to torque it back down and forget about it

however i can't tell you that for a ceramic, personally if it was my car [and it seems that you don't mind work] i'd check the torque FRIST, to see if it's loose, if it is then pull the head off and inspect the headgasket [prolly replace it if was a HG leak]

HOWEVER THIS IS AFTER YOU COMPRESSION TEST THE ENGINE

don't forget that step, cause IF the compression comes up good [which i doubt due to that vid] then you've got other problems

start with the simple easy an CHEAP fixes first

then move on to open heart surgery
 
#19 ·
do a coolant pressure test to determine if the hg is busted. After you get those results, you will then know what to do next. Oreilley's, autozone, or advance auto should have the tester as a rental tool btw.
 
Discussion starter · #20 ·
HKS 240 said:
do a coolant pressure test to determine if the hg is busted. After you get those results, you will then know what to do next. Oreilley's, autozone, or advance auto should have the tester as a rental tool btw.
Click to expand...
Coolant pressure test? How does one do that? I know how to do a dry compression check, but never heard of a coolant pressure test.
 
1 - 20 of 24 Posts
About this Discussion
23 Replies
3 Participants
Last post:
HKS 240
Nissan 240SX Forums
posts
1.6M
members
94K
Since
2002
A forum community dedicated to Nissan 240SX owners and enthusiasts. Come join the discussion about performance, builds, engine swaps, turbos, modifications, classifieds, troubleshooting, maintenance, and more!
Full Forum Listing
Explore Our Forums
S13 240SX (89-94) New Member Introductions General Tech S14 240SX (95-98) KA24DE & KA24E