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KLZE reliability

5828 Views 9 Replies 10 Participants Last post by  marcdh
I need to change my engine on my 6er...
I wanted to get a ze but my father is trying to convince me about the reliability of these engines.... Someone stated to him that every 30 000km, an e-test is required in japan, in if not passed, the engine is replaced... The chances of getting a crappy engine is high and that if I do get a good one, he suspects that within a year, work will need to be done on the engine.... This person is a machinist/engine rebuilder. For double the price, he rebuild my old de engine, oversize's he gives a 1 year warranty....

Anyone care to defend the ze engine (number of years in car, driving style and any major repairs)
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Well the what I have seen for stock piston its only a .1 over bore, I almost had mine done.

My ZE came with a 1 year warrenty.

Nathans ZE was strong as hell when we fired it up.
well, rebuilding a de is fine and great, but if you are going to rebuild it to stock form and keep it n/a, its not worth it at all. i gave up trying to make my de fast.

but it all depends on what you want to do. if its for reliability purposes, go for it. or run the de down to the ground, which will probably be a long time.

its good for boost,

ze is a good platform for n/a power.
indeed, my engine did sound strong and idled great. didn't really have to adjust anything either besides the usual tps stuff

DE is better for boost. lower compression unless you find a low compression ZE. go look in the FI section luminaeus
My ZE has 6 months warrenty and has worked very well for me started no problem, idle's great and feels strong. If you do it right and change things like water pump, timing belt, oil seals etc you should have a reliable engine
Just as others have said, mine is great. Comes with a 3 month warranty. I changed the usual: water pump, timing belt, plugs, wires, pcv, thermostat, oil cooler adapter gasket, headers, touched up the valve cover gasket corner mates with silicone, etc.

She runs strong and I haven't had to adjust a single thing, idle is dead on, etc. And i'm on the stock ECU for reference.
Warranties can be difficult to get honor'd if you're not local to the seller. They don't like to pay shipping of a motor in both directions to get it returned.

Anyway, the biggest gamble with a ZE is DOA. If the engine runs for the first 100 miles, you'll probably have a good one. My original ZE gave me metal shavings after my 100 mile oil change. Then after my 500 mile oil change more metal shavings came out. Then it lasted for 60k of abuse (first Nitrous, then over 300whp of boost) before it was set aside. So even with the poor early history, it ended up being a great motor.

As far as emissions testing goes, the ZE doesn't have an EGR so it *can* (not to be confused with *will*) be difficult to pass. There are a couple ways to get your EGR to work, but that's for you to search in the forums to find out.
Bumping and old thread:

My ZE seems to blow a fair bit of smoke as I recently found out.

Seems like unless you do some thorough research and inspection, you can end up with one that's not as powerful as your DE and in worse condition.

In japan they get rid of the cars so quick, many of them are morons and don't bother changing oil and basically thrash their cars coz it's going to be replaced anyways.

I'm wondering wtf to do about this blowing smoke (possibly burning oil) and I guess inevitably I might have to rebuild the engine.
There's really not alot of difference between the ZE and DE. The only way I consider the ZE less reliable is the weak retainer problem.

Most ZEs are from automatic cars (japs are mostly auto), meaning the engines have never seen a good high rev thrashing and never been past 118mph. However lack of oil changes can have worse consequences. Pop off the valve cover, check for no sludge, no cam rust, light golden to no coloration, no scoring. This will be a strong indication of the state of the engine.

KLZE 30x have you done a compression test?
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