My 82 280zx just started blowing huge clouds of smoke

[toneatron83-280z]

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

[JSM]

The condition of the start is what has me concerned. That just doesn't sound right. 

Did you check to ensure you PCV isn't clogged?  Also check to make sure you water Is not milky. 

[Diseazd]

White smoke usually indicates steam (water). Sounds like it could be a blown head gasket. Fire it up, remove the radiator cap and look for bubbles. You can also check for milky oil or oily water. The aluminum heads are notorious for corrosion caused by electrolysis......always use distilled water in your radiator to keep contaminants (metals) that can lead to destructive electrolysis in your aluminum head out of your cooling system.

Edited February 20, 2017 by Diseazd

[Zed Head]

6 hours ago, toneatron83-280z said:

- 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.

The smoking gun.  What grade of fuel have you been using?

[siteunseen]

You can borrow a compression gauge from chain parts stores "loaner program"

I think you may have advanced the timing then possibly ran it too hard and broke a ring in one of the cylinders.  A quick and easy check would be to pull the plugs and look for one that is much darker than the rest. 

Hopefully I'm wrong, as usual. 

[Zed Head]

If it's coolant then it would be a head gasket, probably.  There are other possibilities.  Hope for a blown head gasket.

[Mark Maras]

 My guess is coolant. Coolant in a(?) cylinder could account for the strange sound when trying to start it. Especially after it's been sitting.

 After it has set overnight, I'd pull all the spark plugs and turn it over with the starter. I'm betting that at least one cylinder will spit coolant out of the spark plug hole. You may find coolant running out as soon as the plug is removed. 

[Diseazd]

1 hour ago, Mark Maras said:

 My guess is coolant. Coolant in a(?) cylinder could account for the strange sound when trying to start it. Especially after it's been sitting.

 After it has set overnight, I'd pull all the spark plugs and turn it over with the starter. I'm betting that at least one cylinder will spit coolant out of the spark plug hole. You may find coolant running out as soon as the plug is removed. 

Absolutely Mark.......good advise.....Not only that, I'll bet if you start with number 6, chances are it's the problem. The large water jacket outlet there seems to tunnel over to the cylinder in a number of cases. Regardless, I'd like to hear back from toneatron83-280z to see if he's tried any of our suggestions. Hard to give further advise if we don't hear back

[siteunseen]

Diseazed, is that the water elbow off the head that feeds the heater core?  I've got mine plugged now but when I put the new hoses and water kock on the core if I have the heat off (water kock closed) does that stop coolant flow from that you are talking about?  I think it will after playing with the functionality of that kock.

Hate to hijack but if it's his DD I think he found another form of transportation. 

[Diseazd]

No Cliff, not that.......If you pull the head and look right behind number 6 cylinder you see the big water jacket (1 1/2 inches or so square)........sometimes I've seen a tiny trench eaten by electrolysis that seeps into number 6. That's why you want to use distilled water and anti freeze to prevent iron, lime and calcium from creating electrolysis, and eating up your aluminum heads.

[siteunseen]

Oh!  I understand, thank you sir.

I used to use water from my dehumidifier for the radiator but then I found gallons for a dollar at the dollar store. 

[siteunseen]

This is what you're speaking of?