e30antonio

I have a 2000 LS400. After my botched timing belt job, I'd rather just get a whole new engine in. I see some legit ones on Ebay that are JDM-imported here to SoCal.

My biggest concern is what I'd need to swap over from my USA 1UZFE VVTi (that was running perfect before I screwed it up) into the JDM engine -- if anything at all.

Also, I'd need it to pass smog. The sellers I've contacted said that the engine can be placed in and, without putting on USA emission components, will pass smog. But I'm kinda iffy on that.

I read a very similar thread here: https://www.clublexus.com/forums/ls-1st-and-2nd-gen-1990-2000/799461-jdm-vs-usdm-1uzfe-vvti-questions.html but I'm trying to gather up as much info as possible.

Yamae

The biggest issue would be the cooling fan. A Celsior's engine uses a totally different cooling system. It uses a hydraulic fan and the control system is not the same with USDM's.

To use many of these JDM parts below would not be practical. In case you use the JDM ECU, the quickest way would be to use original USDM fan and the fan clutch as well as to use electric fans modifying the signal which control the hydraulic pressure control valve.

Other than the fan, there is a minor difference at the purge system. The exhaust gas control would not be a big problem as long as the JDM engine is not too old since our regulation here is as strict as the Californian's except the gasoline vapour. That's why the purge system is more complicated in your state.

e30antonio

By "purge system" are you talking about the EGR system (that's what I know it as)?

I'll be using my USDM ecu, so what sort of bypass for the cooling system would I do?

Currently, to me, it seems like I can simply swap over my USDM components (emission pieces, for ex) and be good to go. So it seems like the biggest problems willl be the "purge" system and cooling?

Yamae

The "purge system" here means to purge the gasoline vapour in the gas tank. The absorbed vapour by the canister is led to the intake manifold using a purge valve which is controlled by the ECU. The Japanese regulation about the vapour is not as strict as US's one and the capacity of the canister is smaller and there are not too many controlling units and hoses compared with yours. I think all you need to do about the purge system is just to use current your car's ones. The JDM engine doesn't use the vacuum port next to the PCV valve line and there is a cap. You need to remove the cap and attach the vacuum hose as is connected on your USDM engine. Other than this, there is another port and a hose at the resonator box. You need to use the current resonator and related parts too.

Regarding the cooling system, I haven't tried that but I think you only need to remove hydraulic related parts and shift the cooling fan with it's attachments.

e30antonio

So long story short, the jdm engine can be done? Im still worried about CA's smog crap, but since it is the same engine (but might not be from the same year as my LS400) and I have a spare USDM engine, I should be good?

Striker223

Why bother with a JDM swap instead of just sourcing a direct drop in?

e30antonio

I like the idea that the jdm ones are instantly ready for pickup and can be compression tested on the spot. I'd really like to go for a USDM engine but I can't seem to find em. Unless Im not looking in the right places.

Other than compression testing, is there any other possible thing to look out for when getting an engine to determine if it'll run properly?

Striker223

Compression testing doesn't tell you much of anything outside of major major issues, a leakdown test is a far better indicator of health

Check the belt and all seals, I would advise just buying a US engine to avoid the hours of extra labor

timmy0tool

iTrader: (7)

i've only had experience using a JDM engine into my honda and getting it to pass smog. what i essentially did was use the bare long block (head and block) only and swapped over pretty much all the US-spec stuff; even the intake manifold, wiring harness, ECU and other US-only accessories were reused. mechanically i think the 1UZ engines are similar between USDM and JDM, so i would imagine this would work just the same.