Headgasket? bad rings? valve guides? - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

Rm240sx · 10-18-2013, 06:58 PM

Hey guys sorry to start this thread but ive got a issue with sr, I was cruising through the neighborhood the other day and I decided to get on it a bit and i did and when I let off it barrelled white smoke... like a freight train. I instantly thought head gasket coolant=white smoke. Then I ran a compression test and cylinders 1,3,4 all 150 but 2 was 120. I put a teaspoon of 30w oil in the cylinder and re tested it and it spiked to 160 so I am thinking wore or cracked rings. But then it sounds like it has a exhaust leak and theres oil coming out of my catch can... by the way no water in the oil, popped the rad cap and no bubbles, I am lost

tauntdevil · 10-18-2013, 07:05 PM

That definitely sounds like a ring issue being that there is no water in the oil and when you put oil in, it spiked because the oil will temporarily block that hole for a split second.

Rm240sx · 10-18-2013, 07:08 PM

Thats what I am thinking it is as well but I was hoping to get input from the sr/240 community rather than my honda driving friends haha

Kallixtos · 10-18-2013, 08:56 PM

Make sure your not overfilled on oil. Easy step to miss.

*fliprayzin240sx* · 10-19-2013, 02:50 AM

Could also be a blown turbo seal but that 120 compression is no good. Minimum per FSM is 125.

Rm240sx · 10-20-2013, 10:22 AM

i think i am just going to tear her down and rebuild her anyway, thanks guys

RedtopTech · 10-22-2013, 06:40 PM

A bad piston ring will cause smoke under load, If you are only getting smoke on decal then look for bad valve seals. Oull the plugs and check for one that is oil fouled or has excess gray soot on it.

Rm240sx · 10-25-2013, 06:10 PM

the cylinder that failed the compression check did however have grey like soot on it. wich would explain the white smoke but why the loss of compression?

10-18-2013, 06:58 PM	#1
Rm240sx Join Date: Oct 2013 Location: Fort Wayne, Indiana Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	Headgasket? bad rings? valve guides? Hey guys sorry to start this thread but ive got a issue with sr, I was cruising through the neighborhood the other day and I decided to get on it a bit and i did and when I let off it barrelled white smoke... like a freight train. I instantly thought head gasket coolant=white smoke. Then I ran a compression test and cylinders 1,3,4 all 150 but 2 was 120. I put a teaspoon of 30w oil in the cylinder and re tested it and it spiked to 160 so I am thinking wore or cracked rings. But then it sounds like it has a exhaust leak and theres oil coming out of my catch can... by the way no water in the oil, popped the rad cap and no bubbles, I am lost

10-18-2013, 07:05 PM	#2
tauntdevil Zilvia Junkie Join Date: Jun 2010 Location: Arizona/LA, California Posts: 476 Trader Rating: (3) Feedback Score: 3 reviews	That definitely sounds like a ring issue being that there is no water in the oil and when you put oil in, it spiked because the oil will temporarily block that hole for a split second. __________________ S14 KA NA two cylinders, 75whp limper

10-19-2013, 02:50 AM	#5
fliprayzin240sx Man w/ CTSV & a Car Seat Join Date: Aug 2002 Location: Tampa Posts: 17,998 Trader Rating: (19) Rides Gallery: fliprayzin240sx Feedback Score: 19 reviews	Could also be a blown turbo seal but that 120 compression is no good. Minimum per FSM is 125. __________________ If you think Zilvia has too many assholes... CLICK HERE!!!

10-18-2013, 07:08 PM	#3
Rm240sx Join Date: Oct 2013 Location: Fort Wayne, Indiana Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	Thats what I am thinking it is as well but I was hoping to get input from the sr/240 community rather than my honda driving friends haha

10-18-2013, 08:56 PM	#4
Kallixtos Zilvia Addict Join Date: Feb 2009 Location: Long Beach Posts: 835 Trader Rating: (61) Feedback Score: 61 reviews	Make sure your not overfilled on oil. Easy step to miss.

10-20-2013, 10:22 AM	#6
Rm240sx Join Date: Oct 2013 Location: Fort Wayne, Indiana Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	i think i am just going to tear her down and rebuild her anyway, thanks guys

10-22-2013, 06:40 PM	#7
RedtopTech Zilvia Member Join Date: Dec 2005 Location: Virginia Beach, VA Age: 39 Posts: 293 Trader Rating: (0) Feedback Score: 0 reviews	A bad piston ring will cause smoke under load, If you are only getting smoke on decal then look for bad valve seals. Oull the plugs and check for one that is oil fouled or has excess gray soot on it.

10-25-2013, 06:10 PM	#8
Rm240sx Join Date: Oct 2013 Location: Fort Wayne, Indiana Posts: 5 Trader Rating: (0) Feedback Score: 0 reviews	the cylinder that failed the compression check did however have grey like soot on it. wich would explain the white smoke but why the loss of compression?