Jump to content
SAU Community

Recommended Posts

Blown Neo bottom end - Next steps?

Welcome to the continuation thread to Blown Neo head gasket - Next steps https://www.sau.com.au/forums/topic/467066-blown-neo-head-gasket-next-steps/

Soooooo another track day, another drama. Did Sandown yesterday, first session went well but started having more and more issues as the day wore on. The engine starting pushing coolant again and had boiling coolant in the overflow despite checking and re-bleeding the system (thanks once again for lending a hand Bill!!). In the last slow session it decided to blow off the PCV hose and push oil + smoke from rocker cover breathers. Sounded like a Rex too.

I got it towed to the workshop and the verdict came in this afternoon, bottom end is gone. It's lost compression on cylinders 3, 5 and 6, and I'm guessing that's probably the root cause for the originally presumed head gasket issues too, so all that expense is likely to have been in vain.

 

If 2016 was the year of dead celebrities looks like 2017 is the year of dead RB25's (hi Johnny)... This one lasted about 150k and ~10 track days @ 275 rwkw so there you go.

Silver lining: My last Sandown PB was 1:34.06 from December 2015 (!) because I was s__t and/or #becausedrama every single time in 2016 ... I only got some 20 laps in yesterday but did grab a string of PB's:

1:32.36
1:32.17
1:31.81
1:30.73
1:29.58

 

So at least this Neo died in style.

Sidenote: The RDA rotors worked wonders with the Intima SR's & brake air guides, and the Nismo 1.5-way is absolute magic on the track.

 

Anyhow, onto the next steps:

I think it's time to get out whilst winning and stop throwing good money after bad. Other than the engine, it's a good sorted car with a 5-page long mod list.

The options are:

  1. Find a replacement engine, get it swapped over and sell is as a sorted, running & regoed street and track car
  2. Buy a replacement block, get the freshened up head transferred onto it, then as above
  3. Stop spending stupid money, pull out all the parts worth anything, and unload as a rolling shell
  4. Something else, you tell me?

Cost of options 1 & 2 will probably be in the 3-5k range (workshop labour) but you'll also get more in selling a proper running car. Flip side, second hand engines or blocks rarely come with warranty.

Having spent hundreds and hundreds of hours and many many more $$$ on this car I was kinda hoping to sell it as a turnkey street & track package for someone else to enjoy, so would really hate to part it out... Plus I don't think it's worth much that way, and you'd end up dealing with a whole heap of tyre kickers.

 

What do you guys reckon?

 

Link to comment
https://www.sau.com.au/forums/topic/468826-blown-neo-bottom-end-next-steps/
Share on other sites

Option 1 should not cost more than $3K

http://www.trademe.co.nz/motors/car-parts-accessories/nissan/engines/auction-1250747254.htm

plus installation should not be more than $1k

Maybe things are different in Aus.

Try advertising it as a project with lots of work already done - just needs new short block and see what offers you get.

  • Like 1

Thanks guys.

13 hours ago, V28VX37 said:

...

The options are:

  1. Find a replacement engine, get it swapped over and sell is as a sorted, running & regoed street and track car
  2. Buy a replacement block, get the freshened up head transferred onto it, then as above
  3. Stop spending stupid money, pull out all the parts worth anything, and unload as a rolling shell
  4. Something else, you tell me?

...

One more option is to get the engine fixed up and at the same time put it back to stock as much as possible, and sell as a running stock car + separate turbo/exhaust/intercooler/intake/oil cooler/gauges/diff etc. Just trying to work out which option will minimise further loss of $$, thoughts?

I've had a look around the usual suspects eBay and Gumtree and there's basically nothing at the moment in terms of Neos, so might need to start calling through the wreckers on Monday.

Can you check engine numbers on FAST? Is there a way to confirm year/type of an RB25 block/full engine based on the engine number? I need to find a 2WD Neo unit, so that there's no further mucking around.

Put another stocker in. Continue enjoying car.

If changing direction... Put stocker engine in, sell car. You cold advertise the parts and remove them as they actually sell. (If you have stock stuff to replace with)

Dirty 30 is another option but not if you want a RWC or plan on selling. Would stick with another neo.

You may sell it with no engine, but I expect the price you get will be less in your pocket than it would be selling a running car, after also paying for the engine being replaced.

  • Like 1
11 minutes ago, Kinkstaah said:

Put another stocker in. Continue enjoying car.

If changing direction... Put stocker engine in, sell car. You cold advertise the parts and remove them as they actually sell. (If you have stock stuff to replace with)

Dirty 30 is another option but not if you want a RWC or plan on selling. Would stick with another neo.

You may sell it with no engine, but I expect the price you get will be less in your pocket than it would be selling a running car, after also paying for the engine being replaced.

^^^ Re last line, yep that's what I'm thinking too. I'll keep looking for an engine.

There's a decent looking block in the FS section but I have no idea how much more work it'd be to mate the existing head onto that, compared to a straight engine swap. Probably lots. With this option I'm also wondering if I can reuse my recently installed OEM HG and ARP head studs, or are they disposable items?

I have a spare OEM HG for sale ;)

But in all seriousness I didn't reuse any of my Tomei Metal HG's even though they claim to be re-usable. Just didn't want to ever risk it.
It would be cheaper to keep the head you have, but its a lot tricker to trust a block unless you know how to inspect it and know it's fine when it's apart. It will save you to do that if you can. It'd be more labour but the block will cost less than an assembled engine. Probably still work out in your favour and then you don't have a spare, perfectly working head.


Then again someone may want that spare perfectly working head for a RB30.
Or you could just get a great deal on a fresh RB28. ;)

  • Like 1

Contact Tony (Blah_Blah above) who may be able to do the labour, or knows of someone who can,  and get some indicative pricing for the main options (complete motor swap or replacement block).

BTW I have reused the same Tomei H/G three times with no problems - but don't think you can do that with other types.

  • Like 1
On 1/27/2017 at 8:48 PM, V28VX37 said:

I got it towed to the workshop and the verdict came in this afternoon, bottom end is gone. It's lost compression on cylinders 3, 5 and 6, and I'm guessing that's probably the root cause for the originally presumed head gasket issues too, so all that expense is likely to have been in vain.
 

What's the logic here? Lost compression wont cause head gasket issues, but head gasket issues can cause lost compression. Are you saying that the head gasket fix didnt take, or that there was a piston/valve issue and that the HG was ok all along?

14 minutes ago, MrStabby said:

What's the logic here? Lost compression wont cause head gasket issues, but head gasket issues can cause lost compression. Are you saying that the head gasket fix didnt take, or that there was a piston/valve issue and that the HG was ok all along?

Correct, one theory is that there a was an underlying piston/ring issue and that the HG was ok-ish all along.

The HG issue was always really difficult to diagnose as on the street the car was fine, on the dyno it was mostly fine, and only on the track did it start chucking coolant – which occurred again on Thursday even after the head refresh, new HG and head studs.

It was comp tested before the HG change and returned reasonable figures so the bottom end was deemed ok. Also powerwise it ran pretty much the original numbers on the dyno after the new HG so I thought it was all a-ok now... But yeah it's an RB so who knows really.

3 minutes ago, MrStabby said:

Weird. So temperatures were ok? (do you trust your temp gauge?)

Yes and no.

Yes in the sense that I didn't cook it this time and the temps started dropping once you backed off the loud pedal. When I cooked it at Sandown last year the temps kept on rising even with no throttle and ultimately hit 125C for water. The root cause for this back then was a minor leak in the cooling system (that I didn't pick up in time), which depressurised the system and significantly reduced its cooling ability.

No in the sense that on Thursday the car would only take 1-2 hot laps before hitting the warning level for water and oil soon thereafter (set at 105C for water and 120C for oil). This is with a brand new Mishimoto radiator and a 19-row oil cooler, and IMHO it should be able to take more than a lap and a half...

I trust my gauges, genuine Defis and sensors all around. I also watch them like a hawk since last year's incidents, to the level that it's actually not that much fun driving as I'm just waiting for s__t to break again. Which it did. 

52 minutes ago, V28VX37 said:

No in the sense that on Thursday the car would only take 1-2 hot laps before hitting the warning level for water and oil soon thereafter (set at 105C for water and 120C for oil). This is with a brand new Mishimoto radiator and a 19-row oil cooler, and IMHO it should be able to take more than a lap and a half...d. 

Yeah that seems very quick to be getting to your limits. Did you push past 105/120 on Thursday? At what temp did the coolant come out the overflow? (or was that from heat soak after stopping the motor?)

Interesting re your water and oil temps

Mines a rb25 neo with a 13row oil cooler?

 

Street temps generally Water and oil 75 to 80c.

 

Track 5 hot laps i think Water still around 80 to 90max. Oil around 105-110c max

18 minutes ago, MrStabby said:

Blah_blah - more or less than V28s 275kw?

On e85 360 to 385rwkw

 

When i had no oil cooler. Yeah i'd see 120c after about 2 to 3 hot laps. Even when i had a stock turbo and and stock engine bout 200rwkw it would hit 120 to 130 after a few laps

1 hour ago, MrStabby said:

Yeah that seems very quick to be getting to your limits. Did you push past 105/120 on Thursday? At what temp did the coolant come out the overflow? (or was that from heat soak after stopping the motor?)

Nope backed off at that point. Overflow level always rose after a session, at one stage about 10cm so heaps. That's when it spat a bit out at the top of the overflow tanks.

Bill and I bled the system in the afternoon, there was heaps of air in there at that point, too.

 

1 hour ago, blah_blah said:

Interesting re your water and oil temps

Mines a rb25 neo with a 13row oil cooler?

Street temps generally Water and oil 75 to 80c.

Track 5 hot laps i think Water still around 80 to 90max. Oil around 105-110c max

Yep absolutely no way I could do more than 2 hot laps at all. Which is strange, as when I first started tracking the car I could do that much with stock rad and no oil cooler, so something's definitely amiss.

52 minutes ago, blah_blah said:

On e85 360 to 385rwkw

When i had no oil cooler. Yeah i'd see 120c after about 2 to 3 hot laps. Even when i had a stock turbo and and stock engine bout 200rwkw it would hit 120 to 130 after a few laps

^^^ Same here.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • As discussed in the previous post, the bushes in the 110 needed replacing. I took this opportunity to replace the castor bushes, the front lower control arm, lower the car and get the alignment dialled in with new tyres. I took it down to Alignment Motorsports on the GC to get this work done and also get more out of the Shockworks as I felt like I wasn't getting the full use out of them.  To cut a very long story short, it ended up being the case the passenger side castor arm wouldn't accept the brand new bush as the sleeve had worn badly enough to the point you could push the new bush in by hand and completely through. Trying a pair of TRD bushes didn't fix the issue either (I had originally gone with Hardrace bushes). We needed to urgently source another castor arm, and thankfully this was sourced and the guys at the shop worked on my car until 7pm on a Saturday to get everything done. The car rides a lot nicer now with the suspension dialled in properly. Lowered the car a little as well to suit the lower profile front tyres, and just bring the car down generally. Eternally thankful for the guys down at the shop to get the car sorted, we both pulled big favours from our contacts to get it done on the Saturday.  Also plugged in the new Stedi foglights into the S15, and even from a quick test in the garage I'm keen to see how they look out on the road. I had some concerns about the length of the LED body and whether it'd fit in the foglight housing but it's fine.  I've got a small window coming up next month where I'll likely get a little paint work done on the 110 to remove the rear wing, add a boot wing and roof wing, get the side skirt fixed up and colour match the little panel on the tail lights so that I can install some badges that I've kept in storage. I'm also tempted to put in a new pair of headlights on the 110.  Until then, here's some more pictures from Easter this year. 
    • I would put a fuel pressure gauge between the filter and the fuel rail, see if it's maintaining good fuel pressure at idle going up to the point when it stalls. Do you see any strange behavior in commanded fuel leading up to the point when it stalls? You might have to start going through the service manual and doing a long list of sensor tests if it's not the fuel system for whatever reason.
    • Hi,  Just joined the forum so I could share my "fix" of this problem. Might be of use to someone. Had the same hunting at idle issue on my V36 with VQ35HR engine after swapping the engine because the original one got overheated.  While changing the engine I made the mistake of cleaning the throttle bodies and tried all the tricks i could find to do a throttle relearn with no luck. Gave in and took it to a shop and they couldn't sort it. Then took it to my local Nissan dealership and they couldn't get it to idle properly. They said I'd need to replace the throttle bodies and the ecu probably costing more than the car is worth. So I had the idea of replacing the carbon I cleaned out with a thin layer of super glue and it's back to normal idle now. Bit rough but saved the car from the wreckers 🤣
    • After my last update, I went ahead with cleaning and restoring the entire fuel system. This included removing the tank and cleaning it with the Beyond Balistics solution, power washing it multiple times, drying it thoroughly, rinsing with IPA, drying again with heat gun and compressed air. Also, cleaning out the lines, fuel rail, and replacing the fuel pump with an OEM-style one. During the cleaning process, I replaced several hoses - including the breather hose on the fuel tank, which turned out to be the cause of the earlier fuel leak. This is what the old fuel filter looked like: Fuel tank before cleaning: Dirty Fuel Tank.mp4   Fuel tank after cleaning (some staining remains): Clean Fuel Tank.mp4 Both the OEM 270cc and new DeatschWerks 550cc injectors were cleaned professionally by a shop. Before reassembling everything, I tested the fuel flow by running the pump output into a container at the fuel filter location - flow looked good. I then fitted the new fuel filter and reassembled the rest of the system. Fuel Flow Test.mp4 Test 1 - 550cc injectors Ran the new fuel pump with its supplied diagonal strainer (different from OEM’s flat strainer) and my 550cc injectors using the same resized-injector map I had successfully used before. At first, it idled roughly and stalled when I applied throttle. Checked the spark plugs and found that they were fouled with carbon (likely from the earlier overly rich running when the injectors were clogged). After cleaning the plugs, the car started fine. However, it would only idle for 30–60 seconds before stalling, and while driving it would feel like a “fuel cut” after a few seconds - though it wouldn’t fully stall. Test 2 – Strainer swap Suspecting the diagonal strainer might not be reaching the tank bottom, I swapped it for the original flat strainer and filled the tank with ~45L of fuel. The issue persisted exactly the same. Test 3 – OEM injectors To eliminate tuning variables, I reinstalled the OEM 270cc injectors and reverted to the original map. Cleaned the spark plugs again just in-case. The stalling and “fuel cut” still remained.   At this stage, I suspect an intermittent power or connection fault at the fuel pump hanger, caused during the cleaning process. This has led me to look into getting Frenchy’s fuel hanger and replacing the unit entirely. TL;DR: Cleaned and restored the fuel system (tank, lines, rail, pump). Tested 550cc injectors with the same resized-injector map as before, but the car stalls at idle and experiences what feels like “fuel cut” after a few seconds of driving. Swapped back to OEM injectors with original map to rule out tuning, but the issue persists. Now suspecting an intermittent power or connection fault at the fuel pump hanger, possibly cause by the cleaning process.  
×
×
  • Create New...