[Ethanissan]

OK I initially thought you were talking about the rear main bearing cap. If it is just the seal housing it will be fine if you can find a replacement.

Ahh yes sorry I can see how I misworded that, should have clarified rear main seal, I didn’t realise the rear cap could also be referred to the same way.

But yeah I’ve lost the other half of the seal, so I’ve just started taking the piston-conrod assemblies apart and cleaning them, so I’m thinking I’ll install those and continue on with the rebuild, and hope that I find the seal as I use up parts.

 

[Ethanissan]

Alright, just a couple pictures of a cleaned up piston/conrod. I’m not too fussed with taking off the stubborn carbon buildup around the soot grooves as I know it’ll just get built up again, more so about cleaning off any grit from me not storing them properly, cleaning out the piston ring grooves, and just generally making them look nicer before reassembly.
Also to re-lubricate the small end so that it’s good when I start the engine, as there’s no oil pressure feed to the gudgeon pins or small end bearings, the oil squirters cool the bottom of the piston, then it looks like that oil just falls into the bearing to lubricate it.

Dirty pistons:

And #1 after mild cleaning (might even do a bit more yet) :

In the second to last photo you can see the wear on the small end bearings. There was no visible movement in them, felt very good, but I am wondering if I should replace them or not.

 

[edb]

Hi Ethan,
after de-greasing the pistons, at the Cat Dealer we used to soak the pistons in a tub of plain tap water to soften the carbon buildup.
Cheers,
Eddie B.

 

[Ethanissan]

Hi Ethan,
after de-greasing the pistons, at the Cat Dealer we used to soak the pistons in a tub of plain tap water to soften the carbon buildup.
Cheers,
Eddie B.

Oh righto, interesting, I’ll give that a go, thanks 👍
I wonder if soaking them in the water based cleaner mixture will do the same thing? It’s roughly a 3/4 mix, 3 parts tap water to 1 part cleaner concentrate.

 

[Bidja]

In the second to last photo you can see the wear on the small end bearings. There was no visible movement in them, felt very good, but I am wondering if I should replace them or not.

Yes, get new ones.

 

[Ethanissan]

Yes, get new ones.

I’ll have a look online and see what I can find 👍

Edit:
Out of curiosity I’ll also take apart a piston from my old engine. Presumably it had done less kms since it’s last rebuild than this one has done since it left the factory, and the gudgeon pin circlips on each end have been replaced (with better designed ones that I’ll use in my new pistons) so I assume the small end bearing has too. I’ll see how much wear they have to compare.
Also have just ordered new NDC small end bearings from eBay, hopefully they get here Monday so I can assemble my new “rebuilt” pistons.

 

[Ethanissan]

Alright, been a few days and been doing things here and there on the engine.

Firstly, I took the injectors to get tested at North Coast Diesel Service in Nambour.
He did a quick test of the spray pattern on the hand pump and said they're average. I'm confident they were rebuilt less than 200,000km ago at the last engine rebuild, and he said he'd rebuild them if I'm doing up the whole engine, but I can run them for now and get them rebuilt at a later stage. That's what I'll do for now, I'll have them rebuilt in a few thousand k's when I'm in a better financial situation.

I also pressed new small end bearings into the conrods, and took them another engine builder, also in Nambour, to have them honed to suit the gudgeon pins, so the pistons are ready to be reassembled. I tried the one in Caloundra first, since when I walk in he just recognises me at this point and I know he does decent work; but he said they sold their small hone a while ago and didn't have one to suit so recommended I go to the Nambour guys for them, so that's what I did.

Currently waiting on the rear main seal to arrive, then I can put the last main cap on, put the pistons in, oil pickup in, sump on, and the bottom end will be sealed up ready to go.

I cleaned up the oil cooler, took it apart and cleaned all the built up cooling system rust out, so it'll be good for another 5000km now .

 

[Ethanissan]

I also took apart a piston from my old engine, rebuilt less than 200,000 km ago, and compared them to the pistons from my new engine, never rebuilt as far as I can tell, 400ish thousand km.

What I found may interest some people, and explains a few things too

Firstly, decked to suit the decked block, no biggie. I also removed my comment from earlier about my new pistons being stronger due to not being decked, since the amount of material that's been taken off these pistons is so miniscule, and only off the tallest layer, not where the crown is thinnest right in the middle.

Now the interesting bit, here's the inside of one of my new pistons:

Clear Nissan logo cast into the skirt there, and "IZUMI" further up. So they are a good quality, genuine piston. Awesome...

Here's the inside of one of my old pistons:

(Conrod is in the way of the heat mark on the underside of the crown in this photo)
That right there I'd say is an eBay piston. Unless someone recognises the logo in which case please let me know. But I'm going for the assumption of ebay piston.
Out of curiosity I held one of each type of piston in the bore of the old engine and lo and behold, the Nissan piston sits quite obviously more snug in the cylinder. The eBay piston has quite a bit more movement in the cylinder. So definitely using the Nissan pistons.

The eBay pistons have definitely seen less heat in their lifetime, so I'll keep them as a backup, but I'll be keeping my EGT's at quite safe levels anyway so I can't imagine heat being an issue for them anymore (who knows if the previous owners of this engine ever had an EGT gauge on it).

(No cracks on either, I did scratch both by accident getting the old rings off)

 

[geeyoutoo]

Alright, been a few days and been doing things here and there on the engine.

Firstly, I took the injectors to get tested at North Coast Diesel Service in Nambour.
He did a quick test of the spray pattern on the hand pump and said they're average. I'm confident they were rebuilt less than 200,000km ago at the last engine rebuild, and he said he'd rebuild them if I'm doing up the whole engine, but I can run them for now and get them rebuilt at a later stage. That's what I'll do for now, I'll have them rebuilt in a few thousand k's when I'm in a better financial situation.

I also pressed new small end bearings into the conrods, and took them another engine builder, also in Nambour, to have them honed to suit the gudgeon pins, so the pistons are ready to be reassembled. I tried the one in Caloundra first, since when I walk in he just recognises me at this point and I know he does decent work; but he said they sold their small hone a while ago and didn't have one to suit so recommended I go to the Nambour guys for them, so that's what I did.
View attachment 549780


Currently waiting on the rear main seal to arrive, then I can put the last main cap on, put the pistons in, oil pickup in, sump on, and the bottom end will be sealed up ready to go.

I cleaned up the oil cooler, took it apart and cleaned all the built up cooling system rust out, so it'll be good for another 5000km now .
View attachment 549786
View attachment 549787

Nambour does have some talented automotive guys whom I have used from time to time.

 

[Ethanissan]

 

[Ethanissan]

It arrived!
Onto assembly!

 

[Ethanissan]

Alright, eventually managed to get the rear main bearing cap in. Because it makes up the sealing surface that keeps the oil in the block it's a tight fit, had to put the stick seals in afterwards. Even then I found that the ebay stick seals were completely wrong, so I said stuff it and put the old ones back in with some gasket maker to make sure they seal on either end.

Also installed the Cam timing gear so the cam and crank are now in time with each other, then installed the timing cover. There's a cover that goes over the IP timing gear that can be removed seperately so I don't need to worry about installing the pump yet.

Pressed the new front crank seal into the timing cover before I installed it too, so that's good to go. It'll seal when I install the harmonic balancer (Don't worry, I'll put some oil on to lubricate it)

.
Really hard to see, but I put the idler that drives the oil pump (drives off a gear on the camshaft) in as well, so when I put the oil pickup and pump on it'll be good to go.

Also went and bought a piston ring installer tool so I'll be able to assemble the pistons.

And then today I went back into Caloundra to the engine builder to ask about cost of getting the head sorted.
He gave me a reasonable quote, so when I take the head in and drop it off to him next Monday, within a couple weeks (he's got a 2-3 week wait time at the moment) he'll take out the valves, do a 3-angle valve grind on the exhaust valve and a 5-angle grind (including the 30* back cut) on the intake valve following @OldMav's angles, run a stone over the head face to make sure it's flat, give it a clean, and reinstall the valves. So essentially a full head service, I drop it off to him and he gives it back ready to drop straight onto the engine. Perfect. Engine should have the head back on in a couple weeks, just gotta do the port matching before I go drop it off to him.

So this'll come back to me nice and clean, and with improved valve angles
I'll need to order an injector seal kit in the meantime too.

 

[Ethanissan]

Alright wasn't going to do this until after the engine was built and running for a while but I've been convinced (thanks Dad).

Took the exhaust manifold to Dats Cool Fab today to get an adapter made up, so I'll be able to bolt the Garrett to the engine for first startup. I told them there's no rush since the head won't be back for a couple weeks, so they'll just do it when they get some spare time. The adapter itself won't be any more than a couple inches long, so shouldn't affect the turbo drive compared to a turbo that would bolt straight to the manifold. It's also a turbo designed for a 3L engine with 18ish:1 compression, being put on a 3.3L engine with 21ish:1 compression. Basically in the low end I'll have better turbo drive than the ZD (that needle valve will be needed for sure), as soon as I get any revs in it though the ZD will blow it out of the water in efficiency.

I tell you what, with how badly the intake is designed, you'd think the exhaust (also designed in the late 70's mind you) would be just as bad, but every time I look at it it impresses me how good of a job Nissan did making the manifold.
It's got nice short runners, so plenty of drive to the turbo, the middle cylinders are angled towards the flange, and I even found out today it's a split pulse manifold, so the gasses don't have to fight each other to get out, they're directed out as if each set of 3 cylinders had it's own manifold. Impressive Mr Nissan, very impressive.

 

[Ethanissan]

Also forgot to mention I decided to take the head in today as well, I figured with that long of a wait time I may as well do it now, so both the head and manifold are off getting stuff done.

 

[Ethanissan]

I’m case anyone in the future is reading this with an SD33T, here’s the thread explaining why bigger injectors won’t do anything, why TD42 injectors won’t work, some mods to do to improve airflow, info about the SD pump and upgrades to it, and how Cummins injectors work, interestingly.

TD42T injectors in an SD33T?

Alright so time in the SD33T rebuild to sort out injectors and I've got a couple options. The first is to get my current set of injectors tested, and if good I'll just use those. I also have a second set of injectors that came as spares with the ute that I'll be getting tested at the same time...

www.patrol4x4.com

 

[Ethanissan]

Progress today!

I got one piston assembled with the conrod, re-ringed and in the engine a couple days ago as a test, but haven't had time to do the rest till today, so that's what I did . All the pistons are now assembled and in
Measured all the ring gaps first fully expecting to have to file them to fit, but turns out they were all pre-gapped and were within spec. Apparently I don't have a photo of any ring in the bore.

Then, I got the oil pump/pickup assembly installed. This is different from something like a TD42 where the oil pump is near the timing cover (from memory), and the pickup runs from the front of the sump where it feeds the pump, down into the oil at the back. On the SD's, the oil pump and pickup both sit in the sump, the pump is driven off the cam gear you can see in the middle of the above photo, and the pickup just goes straight down from the pump into the sump.

Also as you can see I got the harmonic balancer cleaned up and installed as well. I mostly did that so I could use the big nut as an easy way to turn the engine over, but obviously it just had to be done at some point too.
Tomorrow I'll get the sump cleaned up and installed, then the bottom end (internally) will be buttoned up and ready for the head, when that comes back.
The injector pump I do still need to install, luckily you don't have to have the timing cover off to do it on these.


P.S.
Nice one eBay

 

[Ethanissan]

 

[klappers]

Nice head gasket 😅🤦

 

[Ethanissan]

Nice head gasket 😅🤦

Hey the sump would probably hold in combustion better than whatever eBay gave me 😂

just in case it isn’t obvious the engine’s upside down in that photo lol

 

[Ethanissan]

Alrighty, got the head back today from the engine builder, came up a treat!

Multi-angle valve grind (5-angle intake and 3-angle exhaust), head skim, full clean, new valve stem seals, and since the head wasn’t actually that old it still came up the great blue colour they come from factory. Now I can seal up the top end, and just got to wait for Dats Cool to finish the turbo adapter (they’re waiting on a place in Brisbane to laser-cut a ZD turbo flange) then it’ll be properly done. Once I get that back I’ll probably get the manifold machined flat so it seals properly against the head (something I don’t want to have to do twice), figure out how oil lines are going to work with the ZD turbo, and get the engine in the car. Then starts the break-in process before I can start seeing what this engine/turbo/valve grind combo is capable of 😁