What do you all think should be replaced on a J-Spec motor before installing it in my car? i'm not looking for any performance mods, I'm interested in reliability.

-anochie

 

If you're really looking for the engine to last long, then a complete rebuild is the best answer to this question. Without taking the engine apart, just check the plugs/hoses/any connections/belts if any/injectors and make sure they are in good working order. You may want to check the PD while you're at it (I'm assuming your upper intake will be coming off)

 

complete rebuild.

If you are lucky, the housings will be able to be re-used and some people re-use apex seals, but I always replace them, for peace of mind.

Also professionally clean the injectors, replace all the gaskets (some of those motors have been sitting in a junk yard a long long time without running).

 

do you mean the gaskets between the rotor housings?
or exhaust manifold, intake manifold, etc?

 

I replace all, but I don't have the skills or patience to pull the motor apart without damaging them.

Kevin or someone else that has some skill rebuilding might have a different opinion.

 

if the motor costs me $500 is it worth it to just drop it in without rebuilding until I can afford a rebuild from pineappleracing.com?

 

check the compression and condition.

Is it leaking anywhere?

are the plugs intact, or does it look like it has been sitting in a mud hole for the last 5 years?

if you remove the plugs can you rotate the internals by hand with a wrench?

Does it look decent, when looking in the plug holes? or are there chips in the apex seals or rotor faces?

If it checks out okay try it. In worst case you'll have to rebuild it in the future.

But if compression is low, it leaks, or there is water damage, or lots of build up, rebuild it now and save yourself the hassle down the road.

 

so if the compression is over say .... 105 in the front and rear, you'd just throw it in your car wouldn't you?

 

I would, but how do you know the compression?

 

the compression numbers i'll get are what they test at the day that they ship the motor. I'll expect the numbers to remain pretty close to the same during the 3 day trip to reach me. I get a 6 month warranty on the engine too....

 

Where you getting it from? Most tests are performed before they leave Japan, and the ride can be bumpy to its destination. I myself would put it in.

 

Those compression charts are notoriously inaccurate and Tony is right, all the ones I have ever seen were done in Japan.

I would check it myself before installing or be prepared to R&R the motor.

 

I guess im just saying dont be dissapointed if something happens to it. The one I got had a steady 95 psi front and rear, and it still popped. I cant for sure blame the motor, because I believe it was faulty wiring in the car that blew the motor. I drove it when I shouldnt have, before it was running 100%. Sure I was mad when it blew, I tried to laugh it off. I cant say it was a bad deal though. If the next one im getting pops, im going with a rebuild. Being burned twice isnt cool, so im giving the jspec another chance, based on the wiring theory.

 

The company is in Gardena and they're selling me 5 89-91 engines for 500 each and will compression test them in Gardena before shipping to me. I can't remember their name right now even though i've been calling every morning for a week, but i will in the morning. It starts with an "Li"... the rest is on the tip of my brain, but i can't remember.

I'm draining their stock because they don't want to carry rotaries anymore. This way i can have extra engines.

I intend to purchase a single one and see how the company handles any issues (if they come up) before purchasing the rest.

IT'S CALLED LIGERO USA!!! (i remembered the name)

 

anyone heard of them?

 

What, 500 a peice? i want an s5 t2 motor and i was going to have to pay 1k, are you buying all of them?

 

Can you put a 89-91 n/a engine in a 87 n/a

 

Bro I need a 89-91 TII engine! Let me buy one, if anything for me to rebuild! My car's been dead for 5 months now and I'm still trying to save money for a new engine.

C'mon man! Let's all share! :-D

Hell, even EMAIL me... oldmanwilly666@aol.com

 

i'll probably sell a couple for $700 +shipping.

 

ok, I got the test back from the first motor they are sending me. 125psi front and 120 rear. Are those numbers unreal for a used motor imported from japan?

 

those are VERY good numbers. i just got a jspec. i don't know exact #'s but it has good compression from the EAR test right now its soaking in ATF

 

anyone know what the compression is supposed to be when the motor is brand new?

 

If you’re going to the considerable expense of having the motor completely rebuilt (worth every penny), then why buy another motor to rebuild? Why not just rebuild your own motor? There’s no advantage to using a J-spec motor over a US-spec one.

 

You must consider that in Japan most people use public transportation and must pay high premiums for cars older than 5 years. Japan is also extremely small and exceeding 30,000 miles witihin 5 years isn't so common. I just got a complete J-spec TII motor w/turbo for $500 bucks. By just removing the exhaust manifold and using a flashlight and dental mirror I inspect each apex seal and housing as I slowly turn the motor. I'm not taking mine apart...I did discover some interesting spec information, but I'll do that on another post...
Getting back... the compression test that was done is inncorrect. First it would need to be turned with the starter or similar device, not by hand. Unlike piston engines, the process to determine compression on a rotary is quite different. You must watch the 3 pulses as the compression climbs to its maximum. Each pulse should be somewhat equal to each other, like 40-40-40. Let's say one apex seal is damaged the other 2 are good. When cranking the engine you must watch the pressure gauge starting from 0 and you should see something like 40-40-15 or 40-15-40, which gives you a total of 95. If you go around one more time, just one of the undamaged apex seals will take it past 100. In fact even had you 2 broken apex seals the 1 good apex seal will take you past 100 but it'll just take a couple more turns. Another thing, cranking RPM, and engine oil weight and temperature will have a direct affect as well

Arpus if you have a 89-91 motor and a 87-88 RX-7 there are some changes you will have to do... coolant inlet /outlet location, Fuel Injector resistance, oil metering pump, twin scroll turbocharger setup, TPS, intake...
Maybe we should trade cause I have the J-spec 87-88 TII motor but a 89-91 TII car. argh!

Sensei

 

my car is a 89... I know someone who is looking for an S4 turbo engine if yours is in good order, i can give him your email address.