3L retrofit - boring out 3.5mm

[GreenPump]

As detailed in another thread, I am likely going to be rebuilding my 2.8 diesel.

Because the 3L and 5L engines (5L with mech injection) are incredibly similar, I have considering swapping in a low mileage 5L. Finding one has so far proved difficult. I don't know of anyone that imports them.

Another option could be boring out my existing bottom end 3.5mm and then rebuilding with a 5L kit and heads. Has anyone tried this?

On a side note, how much more lively is the 5L than the 3L?

 

[mudgudgeon]

3.5mm is a lot to bore out. You'd want to try and understand if there was a change in block castings to accommodate the bigger bore of the 5L

 

[Dougal]

Why not look at a 1KZ or 1KD? The 3L is a basic motor to put modification money into.

 

[Eurasiaoverland]

I remember searching for exactly this question years ago, and pulled up a thread on an Australian or NZ forum where someone had tried boring out either a 2L or 3L block to the 5L size and blew throught to a coolant passage. Not sure if you could make it work with wet liners.

I've only driven a 5L-E and while it was noticeably more powerful than my 2L, it was still underpowered for the car it went in (an LJ120 Prado). Given that you already have a 3L and are looking for a mechanical 5L engine, I would say the difference will be marginal and not worth any serious money (though I appreciate a 3L rebuild may be serious money if done properly, but at least you get a like-new engine).

I wouldn't touch a 1KZ, a 1KD would be great but comes with electronics and ECU and (in early models) some potentially serious problems if maintenance was not excellent. A 3RZ or 5VZ would be much cheaper and easier to get in North America and would be a revelation after a 3L.

 

[GreenPump]

I wouldn't touch a 1KZ, a 1KD would be great but comes with electronics and ECU and (in early models) some potentially serious problems if maintenance was not excellent. A 5VZ would be much cheaper and easier to get in North America

Appreciate the reply.

I've come to the same conclusion that boring out my current engine is not an option. Additionally a 5L with mech injection is not worth finding/importing for marginally better performance.

My plan as of right now, I am planning to rebuild the 3L and put on a turbo kit. Northwest Toys out of Oregon sells a lot of stuff, but they charge an arm and a leg. I'd be in like 9 grand to rebuild, modify my pump, and use their valve and turbo kit. That's if I do everything myself.

I'm going to call HD Automotive in Brisbane this afternoon. They have a great reputation with their kits, and they sell a rebuild as well. For about half the price.

Hopefully they will be willing to ship internationally. Their website says they will ship via DHL.

Planning to pull my engine Friday. I'll post pictures.

 

[Dougal]

The 1KZ doesn't have any serious problems. Past ~2000 they stopped cracking heads.
The 1KD is as solid as Toyota diesels get these days. They made them from ~1998 to ~2014.

Turbocharging a 3L is relatively easy, but you're stuck with an engine that can only handle low boost. The heads and cranks aren't tough enough.

 

[Eurasiaoverland]

Appreciate the reply.

I've come to the same conclusion that boring out my current engine is not an option. Additionally a 5L with mech injection is not worth finding/importing for marginally better performance.

My plan as of right now, I am planning to rebuild the 3L and put on a turbo kit. Northwest Toys out of Oregon sells a lot of stuff, but they charge an arm and a leg. I'd be in like 9 grand to rebuild, modify my pump, and use their valve and turbo kit. That's if I do everything myself.

I'm going to call HD Automotive in Brisbane this afternoon. They have a great reputation with their kits, and they sell a rebuild as well. For about half the price.

Hopefully they will be willing to ship internationally. Their website says they will ship via DHL.

Planning to pull my engine Friday. I'll post pictures.

Toyota turbocharged the 2L and you can read about the 2L-T routinely cracking heads on here and any other owner forum. They never tried it on the 3L or 5L. Indirect injection diesels concentrate heat in the pre-combustion chamber of the head (this is where the compression occurs, and where the combustion at least starts), and the head is fundamentally weaker because it has to accomodate the pre-combustion chamber. This seems to be fine on a normally aspirated and low stressed engine - the legendary reliability of the 2L, 3L, B, 3B, 1HZ testify to this, but once you turbocharge it you have an engine which is very vulnerable to overheating - a poorly flowing radiator, malfunctioning viscous coupling, coolant leak etc can easily lead to an overheat and on these engines, that very likely means a cracked cylinder head. This would be fine if you had a cheap turbo and a throw-away engine, but for 9k USD??? That's an outrageous price. Practically double what I paid earlier this month for a complete, low km 15B-T engine with all accessories that came straight from a Japanese military vehicle (given I am in SE Asia where availability and shipping are not an issue).

Sure you will find stories of people running home-turbocharged 3Ls, 3Bs etc for years, but that's survivor bias. Just try searching for cracked heads on 2L-Ts, 1KZ-Ts and you'll get more threads than you can read - especially on non North American forums. Same on user-turbocharged 3Bs. Here in SE Asia the 2L-T and 1KZ-T are not taken seriously as a Landcruiser engine for anything other than road driving. The 1KD however is very popular (though a much more complicated install) and I agree, an amazing engine, though it did have teething problems. The direct-injection B engines are the ones to go for, though they are probably too heavy for a Hilux Surf and are fundamentally lorry/bus engines which feel quite different from the car-like 2L/3L.

I would just open up the 3L and make a call from there. Almost certainly all the pre-combustion chambers will be cracked. If the head is also cracked then you're into serrious money vs. risking Chinese components to keep it running. All being well, I would just do a nice rebuild on the 3L with a local machine shop - it's an easy engine to work on with great part availability (globally). Then just enjoy the slow 3L experience. I did a 4+ year, 150,000 km road trip in a Hilux with a 2L and, yes, they are slow (I once got pulled off the German autobahn for driving too slowly ) but other than that they are great engines.

If you're willing to drop 9k on it then you have a lot of engines to look at there. IMO the only decent engines they ever put in the second and third generations of Hilux Surf were the 3L, 3RZ-FE, 5VZ-FE and 1KD-FTV. I would be picking from that list. North America is, surprisingly, about the only market where the 5VZ came with a manual transmission and that would make a very nice on- and off-road vehicle.

Oh, and I forgot earlier, I have driven a 5L - it was in a friend's LN168 off-roader and is/was turbocharged. It really went nicely but had a short life before the overheating problems started.

EDIT - just looked at your profile picture more closely and see that we are probably talking about a JDM LN10*, so ignore my comments regards a Hilux Surf.

EO

 

[GreenPump]

This might be blasphemy...

But what about an OM617? It should fit, there's adapter plates, and they are easy to find stateside.

Big power upgrade from the 3L. Both robust, cast iron engines. Similar fuel economy as well.

 

[Eurasiaoverland]

This might be blasphemy...

But what about an OM617? It should fit, there's adapter plates, and they are easy to find stateside.

Big power upgrade from the 3L. Both robust, cast iron engines. Similar fuel economy as well.

Well I know nothing about Merc engines but from a quick search it seems they are even older than the L Series... if you can find a good turbo unit, it could be good upgrade. But are there bigger, direct injection 4 cylinder Merc engines available there that would fit? What about a Cummins 4BT? (I also know nothing about Cummins engines). Looks like you have a leaf-sprung SFA Hilux (nice) so would be easy to uprate the springs for the extra weight.

 

[GreenPump]

Well I know nothing about Merc engines but from a quick search it seems they are even older than the L Series... if you can find a good turbo unit, it could be good upgrade. But are there bigger, direct injection 4 cylinder Merc engines available there that would fit? What about a Cummins 4BT? (I also know nothing about Cummins engines). Looks like you have a leaf-sprung SFA Hilux (nice) so would be easy to uprate the springs for the extra weight.

There is something special to me about the old, fully mechanical diesels. I'd feel a sense of loss doing a swap to a newer diesel.

 

[Eurasiaoverland]

There is something special to me about the old, fully mechanical diesels. I'd feel a sense of loss doing a swap to a newer diesel.

That's exactly my brief (on my BJ60 restoration) - a fully mechanical direct injection 4 cylinder turbo diesel. All the good stuff before the ECUs came. Not saying EFI diesels are bad, but not what I want.

 

[Dougal]

This might be blasphemy...

But what about an OM617? It should fit, there's adapter plates, and they are easy to find stateside.

Big power upgrade from the 3L. Both robust, cast iron engines. Similar fuel economy as well.

Plenty of people have put those into similar vehicles with disappointing results: OM617 Performance Review - https://www.4btswaps.com/threads/om617-performance-review.74457/

A Toyota 1KZ does everything better, including fits better and keeps parts supply and resale value.

 

[GreenPump]

I've decided to rebuild the 3L. I will be overhauling the entire engine.

Dave at Back40 Imports is going to do my pump and injectors.

First step was to pull the engine. Having not done it before it took some extra time. The whole afternoon pretty much.

Now it is in the shop on a stand! Good start.

 

[GreenPump]

Further teardown. Had some time today. I'll probably pull the heads off tonight. Honestly other than being totally gunked up, things don't look too bad.

 

[Eurasiaoverland]

Nice work, bringing back nice memories here as the 2L was my first engine rebuild.

Indeed, that engine looks almost new, what year is it? If the rest of thw vehicle is that good it would be a shame to modify it in my (unsolicited) opinion!

Can you get it to make the knocking sound when turning over by hand (don't turn it with the belt off until you've taken the camshaft out)?

 

[GreenPump]

Factory cross hatching still on the cylinder walls...

 

[Eurasiaoverland]

Factory honing - that is nice to see! Can't be many L engines like that these days.

Maybe you've hosed it down with brake cleaner, but to me that crank looks worringly dry.

 

[GreenPump]

Maybe you've hosed it down with brake cleaner, but to me that crank looks worringly dry.

Yeah, I hosed it down with about three cans of Brake Cleaner before I took the heads off.

 

[GTSSportCoupe]

Factory honing - that is nice to see! Can't be many L engines like that these days.

Maybe you've hosed it down with brake cleaner, but to me that crank looks worringly dry.

Every L (2LTEs and 3Ls) engine I've seen a picture of or had apart myself has factory honing still. The quality of the bottom end is not inferior to other Toyotas of that time. That said, this motor looks particularily good.

Just in general to the OP:

The bottom ends are strong, and usually any problems there are from people using the wrong head gasket (too thin) when replacing a cracked head. This leads to pistons kissing valves slightly and taking out BEB after a while. So make sure you follow the factory procedure to measure piston protrusion when you do this rebuild. Or just buy thickest head gasket to be safe.

2LTE and 3L heads are strong too as far as boost or cylinder pressures go. It's heat cycling from localized boiling around the pre-cups that leads to the cracked heads. Avoiding that and high EGTs, and the motors can take a lot of abuse actually. I abuse my 2LTE hard, so went to a waterless coolant to avoid the localized boiling issue.

Glad to see things are not looking too bad on your motor! I guess the sludge problem has not been that long.

Is the cylinder head ok? This looks like a crack?

 

[Eurasiaoverland]

Every L (2LTEs and 3Ls) engine I've seen a picture of or had apart myself has factory honing still. The quality of the bottom end is not inferior to other Toyotas of that time. That said, this motor looks particularily good.

Yes, that was not the best considered statement on my part! I was thinking high km 2L/3L/5L engines needing a rebuild, I guess the lower km engines with head failure should still have honing.

Good spot on the crack, though the direction of propagation looks odd to me. Maybe a little oil droplet which has streamed down when the head was turned on its side?