Hi all. My 1982 280zx refused to start a few days ago in a very strange way and then, when she did start, blew clouds of white smoke.

 

Before I have her towed to a mechanic, I'd really appreciate the opinion of club members as to just how much trouble i'm in for. This is my daily driver, so it's fairly urgent that I do something about getting her back on the road.

 

She had been running really well - plenty of power, including uphill, with very little exhaust smoke. Oil level hasn't moved since I last serviced her about three months ago.

 

When I turned the key the other day, the starter kicked and I could see and hear that the engine was attempting to turn over. The battery and alternator are quite new. I also have a lithium ion jump starter that I plugged in, so I was fairly confident that battery wasn't an issue.

 

After four or five tries, the engine very slowly turned over with a kind of squelching noise, like rubber against metal, and sprang to life - with a cloud of smoke from the exhaust that hadn't been there before.

 

I drove her around the block the next day and there was no noticeable difference in power. Still plenty of compression, but with what seemed to be something intermittently freezing up/dragging in the engine, accompanied by constant and copious clouds of white smoke.

 

Obviously I don't want to exacerbate the issue, so I drove straight home and the car is laid up in the driveway.

 

- I don't have a compression tester, so my saying 'plenty of compression' is based on the performance of the engine under load.

- I had the manifold cover off a few months ago and did the valve timing. Everything looked surprisingly good. Nice clean oil, with very little varnish on the cam and rockers. I'm fairly confident I torqued everything properly afterward.

- I have suspected that the oil seals are in need of replacement for a while as there seems to be a little bit of oil blow-by, particularly when the engine is cold.

- I advanced the timing a week or so ago, to around 20 degrees when it would normally sit at around 10. She seemed much happier, easier cold starting and a fair bit more power. But I'm guessing that I pushed her a little bit too far.

 

Other stuff

- Oil is Penrite HPR30 20W-60

- Oil filter, sparks, leads, dizzy cap and rotor, fuel filter and air filter are all pretty new

- I've systematically gone through all of the EFI components, tested, adjusted and repaired

- Cold idle has been rough for a while, with occasional misses and splutters, but she ran fine once warmed up.

 

Any ideas folks?

 

Thanks in advance

1 hour ago, Diseazd said:

Cliff.....The large water jacket is a common problem area, but any of the smaller jackets can cause problems too

I see something to read up on.  You're head bolt holes are threaded, mine aren't on that E31.  Is that something you did or do all P79s have that? Thanks!

Hi all. Thanks for your suggestions. Just got home from work.

I pulled the plugs and cranked the starter - sure enough, there is a whole lot of water in cylinder 6. So I guess it's the head gasket? If so, good news I suppose. Could be a lot worse!

I've always used quality coolant, but I've only had her for 5 out of her 35 years. The radiator was certainly full of plain old water when I took ownership. That said, the radiator was in fairly good condition and didn't run brown when I first drained it.

1982 280zx 2+2 non-turbo, auto in Melbourne, Australia

These engines are prone to detonation and detonation is a very powerful force in the combustion chamber that can cause damage.  When you advanced the timing you made detonation more likely.  Or, it's just got miles on it and it finally let go when you were hooning around enjoying the extra punch.  Pretty cool though, how these guys narrowed it down to the exact cylinder and details of what you would see, huh?  Wizards.

Now you can start a new thread soon, titled  "how do I remove this broken bolt/stud fragment from my head/block/whatever".  It will be fun.

10 hours ago, siteunseen said:

I see something to read up on.  You're head bolt holes are threaded, mine aren't on that E31.  Is that something you did or do all P79s have that? Thanks!

That's an F54 block not a P79 head   All blocks I've dealt with are threaded.....

59 minutes ago, Diseazd said:

That's an F54 block not a P79 head   All blocks I've dealt with are threaded.....

Egg on face.  Sorry

I looked at a head in my spare bedroom to see that water hole then looked at your picture.  Looking back those 6 cylinders are a dead give away. 

Still check the oil for milky condition.  You want that oil out of your motor ASAP if there is water in in.

I'll check tonight after work and if it's milky I'll drain it, thanks JSM. I'm waiting on a ballpark quote from a cylinder head specialist.

1982 280zx 2+2 non-turbo, auto in Melbourne, Australia