Outer Limits 4x4 Board

Just a few small questions about my NJ exceed.

Reading the bible stuff on the 3.5 DOHC engine ... why is it a bad engine for gas? i got gas a year ago and now its running like shit .. was it a bad choice? Think i will have to pull the heads off - it backfires now (on gas) so im thinking burnt out valve? I am an engine recondition though so the work is cheap

I have a problem with the alternator light (and A/T light though i think they are joined somehow) being permenatly on but not fully luminated. Somedays its very dull and somedays it bright though i have never had a flat battery... any ideas?

My air con works for about 5 - 10 mins everyday and then turns off. I took it to a gas place and they said all the hardware is perfect and when they bypass all the electrics the aircon works fine. They couldnt isolate the problem and said it was maybe in the aircon module somewhere... has anyone had this problem

Come on can nobody help me here?

OK, I'll see what I can do.

Who said the 3.5 is a bad engine for gas? AFAIK, it's only the 12 valve 3.0 V6 which isn't recommended for gas (something to do with the valves/seats/heads - I don't recall) but I could be wrong.

Although Mitsubishi advise against gas on the 3.0, some people have had no problems - and other people have had massive problems.

If you suspect a burnt valve then test for it!

NFI on the alternator & A/T lights. Alternator light can be a dud diode, but NFI on the A/T.

Air con could be a TX valve. Crud builds up in the refrigerant lines (not sure why) and can intermittently block the valve. Mine wasn't discovered until the third time I sent it back, and they'd been running it for most of the day before they noticed a problem. It's possible your car needs to be driven (accelerate/brake/bumps) before this problem will show up - perhaps they need to actually drive it, rather than sit it in the corner of the workshop.

Good luck,

Scott

http://www.outerlimits4x4.com/viewtopic.php?t=17870 It was a page in the tech guide relating to the 3.5 L engine "The other pronounced difference is the DOHC are not gas happy. The SOHC 3.5L though is fine"

From my experience the 6G72 (3L) engines have soft seat but the g674 (3.5L) have nice hard seats - very thin though.

I am leaking coolant out the side of a head so i will have to take them off anyway.


Is the T/x something i can fix or just take it to a different aircon place and suggest they check it out?

I actually talked to a Mitsu tech about the difference in the DOHC in the NJ and NK . Was told only the NK 3.5 is gas compatable. It was about 1997 that they started making all the motors gas compatable with the likes of Challengers and Triton motors as well.
Dave

The 3.0L model in the NK is OK on gas as they came out with a 24 valve single cam motor (I think it was the same as the Triton - I think the engine number on these models are 6G72AC.. whereas earlier model engine numbers were 6G72AA..). All earlier 3L models had poor valve seats and were not recommended for LPG. I have read that LPG compatible heads are stamped with LPG on them.

Where did you find an NK with a 24V 3.0 V6? I thought they were all 3.5 by the NK?

[quote="-Scott-"]Where did you find an NK with a 24V 3.0 V6? I thought they were all 3.5 by the NK?[/quote]

In my garage. Mitsu did make a 3L NK. Initially I was skeptical that my Mitsu may have been a re badged earlier model (especially since mine also has rear leaf springs) but the compliance plate does state that the vehicle is an NK 3L made in late 96. Another difference is that all earlier 6G72 motors began with 6G72AA.. but mine began with 6G72AC... The only other vehicle which I have found the 6G72AC.. engine number on was MK Tritons. The the main difference with the motor was the motor was a 24 valve single cam motor as opposed to the double cam 24 valve motors in earlier models.

It took alot of research to find out that the motor was LPG compatible which I finally got off a Mitsu webpage and confirming by ringing Mitsubishi - this web page also showed other makes if anyone is interested. Mitsu did have a webpage where they stated what cars were and were not
It looks like they have taken this webpage down but I have a copy saved on my PC which I can forward if anyone needs it.

Looks like I've got one of the only 3.0L NK's in Aus and to tell the truth I would probably prefer a 3.5L but I got the car for what I thought was fair price (5K), it has not let me down (other repairs you would expect for a car with over 200K on it).