S2 Stagea RB25DET NEO stockish rebuild thread

[QLDR31]

 

Hey guys,

I finally have some time and cash to do a rebuild.

I haven't done a rebuild before so any advice would be appreciated.

I'm doing a rebuild because my engine was overheating. I had a coolant leak between cylinders 5 and 6. When the head came off pistons 6 looked clean because of the coolant going on it. There wasn't any coolant in the oil.

The car had around 240K on the clock, I did about 160K of that. Apparently some time previously someone had patched the head gasket. So the patch lasted pretty well.

The car has been off the road now for over 2 years.

The car is fairly stock only mods are R32 GTR center cluster and R34 GTT rims. The auto gearbox has been replaced with a second hand one that was tricked up.

I got a couple of quotes to fix the engine. One was $10k for a forged etc engine (id have to fit it myself). Another quote was $6k for a bodgie repair job not touching the bottom end.

I have always wanted to rebuild an engine so I decided to bite the bullet and do one myself.

I'm not looking at doing a super build. Just a pretty stockish one. Thinking of adding a turbo back exhaust after the rebuild. I also have some KYB shocks to go in.

The head was dismantled and cleaned by one workshop. Still in pieces. Apparently it is good to get reassembled. They also said the turbo looks in good nick.

I am planing on reusing the pistons. New rings?, ACL Racing bearings, ARP main and head bolts, Full Nissan gasket set.

One of my mechanic friends recommended replacing the rods with Maxspeeding rods. He used them on a SR20 and said they are good quality. Very similar or the same as Eagle rods.

So recently I dismantled the block.

Took the block, crank and pistons to Engine Engineering at Rocklea QLD. They have acid cleaned the block, honed it and decked it. They are currently checking the pistons and cleaning them. X-raying the crank and linishing it.

Today I painted the block with 3M  300deg c Engine Enamel Ford Light Blue. I think it looks pretty rad.

Let the rebuild begin.

Brendan

[daneprostamobrown]

i would suggest afew things for reliability.

get a crank collar fitted and billet pump gears. very cheap insurance and may as well be done while its out. these stock sintered gears break not just on limiter, but randomly too. 

nitto head drain. once again cheap as and great for oil control. 

forged rods of whatever brand with arp studs. not only stronger but lighter so engine will accelerate faster due to lower inertia. balance with crank and stock pistons  

if arp main studs you will have to get the tunnel measured and probably honed to get it round again. 

new genuine balancer and arp balancer bolt if the balancer is old as with lots of km's.

brand new tensioner and idler bolt and stud and new bearings 

spend money on a good ecu with oil, fuel and coolant pressure and temerature sensors for engine protection. you can flog the living shit out of an engine with all that. big turbo and supporting mods is just optional for the future at that point.

 

[QLDR31]

On 8/7/2021 at 9:30 PM, daneprostamobrown said:

i would suggest afew things for reliability.

get a crank collar fitted and billet pump gears. very cheap insurance and may as well be done while its out. these stock sintered gears break not just on limiter, but randomly too. 

nitto head drain. once again cheap as and great for oil control. 

forged rods of whatever brand with arp studs. not only stronger but lighter so engine will accelerate faster due to lower inertia. balance with crank and stock pistons  

if arp main studs you will have to get the tunnel measured and probably honed to get it round again. 

new genuine balancer and arp balancer bolt if the balancer is old as with lots of km's.

brand new tensioner and idler bolt and stud and new bearings 

spend money on a good ecu with oil, fuel and coolant pressure and temerature sensors for engine protection. you can flog the living shit out of an engine with all that. big turbo and supporting mods is just optional for the future at that point.

 

Sound like good suggestions. I'll look into all of them.

I might get an ECU at a later date.

[QLDR31]

I ordered a NPR piston ring set, ACL race series bearings and Maxspeeding rods. 

I have received the ARP head and main studs.

[QLDR31]

I've been working out which parts of the gasket kit are for what. Most parts are easy to identify.

If someone could guide me on these it would be great.

I think D is the temp sensor. B is about the same size, but D is thicker.

Not sure on the other seals and eye bolt gaskets. 

 

On the following picture we have valve stems, crankshaft and camshaft seals. Is there a way of telling the valve stems apart?

The big seal is obviously for the crank. I think the seal with the valve stems is also for the crank. I'm also thinking the two seals with the large crank seal are for the camshafts.

 

[Duncan]

Don't overthink it at this stage. Just check against what you remove and pay attention to sizing when you refit. The kits can be very comprehensive and you may well have parts left over.

My guess is C is the sump plug washer and D the oil strainer o ring, but like I said, check against what you take off. A and B are probably turbo water and oil banjo bolts respectively.

The front crank and cam seals are identical so you will have 3 of those the same. The large seal is the rear main seal for the crank.

[QLDR31]

Cheers Duncan.

The two camshaft seals have different part numbers to the two crankshaft seals. The smaller crankshaft seal does look similar but I don't think its the same. I haven't taken them out of the bag yet.

The sump plug seal is in the bag to the right.

But yeah i'll work it out.

One workshop pulled my head apart and cleaned it. I found this workshop unreasonable priced. I'm not game to reassemble the head myself. So i'm getting my machine shop to do this. They are going to check that it doesn't need any machining. Then assemble it.

Edited August 17, 2021 by QLDR31

[Duncan]

Good choice, I've had a few good head jobs and have always found them worth every cent, and way better than trying to do it yourself.

[QLDR31]

I nearly have all the parts now. Maxspeeding rods (around 125grams lighter each than originals). ARP head and main studs. Plazmaman billet oil pump and crank collar. ACL race series bearings. NPR rings. Ross head oil drain. OEM Thermostat.

Just need timing belt and tensioners, injector seals, belts. Maybe replace some hoses. Thinking about getting billet half moons as lost originals. Thinking of reusing the OEM water pump as was replaced recently.

Apparently my head was a bit bent. So all up it's going to cost $1400 to sort the head. Ready to drop on.

Yesterday I setup for a Ross head drain.

[QLDR31]

I got the head back from the machine shop. Apparently the block and crank need to be final cleaned. The guy at the machine shop said best to wash with hot sopy water. Scrub bores with a large pipe cleaner. and scrub the galleries as well. Rinse off then blow dry. Wipe the bores with a clean rag and repeat until no grim is found.

Any one done a final clean on their block and crank?

I'm guessing i'm going to need to remove all the welsh plugs. I'm not really keen to do this.

I can get the machine shop to do the final cleaning if needed.

I bought some multi point sockets for the ARP stud and nuts. I bought 10mm, 13mm and 16mm. These metric sizes ok or should they be imperial?

The head is wrapped in plastic. Apparently I just need to give it a good blow out before assembly.

[Duncan]

Welsh plugs should be OK, they only go to the water galleries and they don't have to be spec free like oil galleries.

Yes, I'd pressure wash it, dry with compressed air or leave overnight,  then wipe bores clean with clean rag with light oil or wd40

[QLDR31]

Hopefully I'll get this motor together over the Christmas break.

I ran into one minor problem today. Getting the cap off the conrod. I've taken the bolts out but caps dont want to come loose. I don't really want to purchase a conrod cap splitter. Anyone got any tips?

 

 

[GTSBoy]

Soft faced mallet?

[QLDR31]

On 12/27/2021 at 6:42 PM, GTSBoy said:

Soft faced mallet?

Yeah I tried that a bit. Loosened one a bit. Maybe if I kept at it.

I'm thinking of making a splitter tool made out of a bit of pipe chopped in half. With bolts to separate it.

[QLDR31]

Torque Settings?

ARP instructions for main studs says 60fp for an RB26.

ARP instructions for head studs says 80fp for a generic 7/16inch diameter.

I've seen a few threads about ARP head Torques of 72fp (just under 100nm and others around 100nm).

I'm thinking of going 72fp for the head and 60fp for the main.

Anyone got any recommendations?

Cheers

[QLDR31]

I made this to separate the rod caps:

Crank torqued up:

Having difficulties getting the gudgeon pin into stock pistons, Anyone got any tips?

[Duncan]

There are clearances listed in the manual for the pins, I've found some tighter and looser in various rebuilds. Either way, lightly tapping them in should be more than enough if you aren't going to check them

[QLDR31]

The first four pins were nastie to get started. My 5th and 6th pins went in relatively easy. I can see why some people keep the pin partially in the piston.

Now i've run into my next problem. The NPR 2nd ring doesn't fit right. The oil rings and top rings look alright.  I saw on one of the DriftSquids RB30 budget build Youtube videos that Nissan rings are needed. I better get ordering. I wonder if anyone in Brisbane stocks them?

 

[QLDR31]

Looks like I might of put the 1st and 2nd rings around the wrong way. 1st is middle and 2nd is top.

Nah that didn't work either.

Edited December 30, 2021 by QLDR31

[Duncan]

It is important you check the ring end gaps before installing. Push each carefully into the bore and check the gap with a feeler gauge. The rings should have the required end gap in the included doco