Black smoke fixed now blue smoke

Problems, ideas and comments specific to engine swaps.
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chunstone
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Joined: 04 Nov 2007 09:12
Location: Wenatchee, Washington

Black smoke fixed now blue smoke

Post by chunstone »

just did the following;
Diagnosing my black smoke problem I found the distributor to be bad as well replacing the computer.

I now have;
rebuilt Hitachi distributor (made in Japan)
1986 automatic transmission computer, part #A18-653M23
02 sensor is a Nissan,17mm titania part # 2269001P00
When I got the car the engine was supposed to be freshed up.

All indications say that the car had not been driven much if any for anywhere from 5 to 7 years. Do not know much about the operation of the engine from the previous owners.

I have driven the car about about 400 miles total.
The engine preforms the same as it did when I first started driving it.

Now I have blue smoke.
NOT upon startup.
Blue smoke idling (light) after acceleration and after shifting gears (heaverier smoke).
I had a compression test done.

#1 was 205
#2 210
#3 205
#4 215
#5 220
#6 210

I talked to moter heads and they think that the oil rings are stuck. A Google search suggested the following;
Rebuild engine, or;
Pour ATF or Marvel Mystery oil into the sparkplug holes after warming up and let sit 24 hrs. Do this 3 or 4 times if necessary. Add other solvents into the sparkplug holes,
Use synthetic oil as it has better detergents.
Add Marvel mystery oil to the gas and the oil.
Before I try any of the above, do any of you have any ideas about unsticking oil rings in a VG 30 engine?
Thank you for helping, Neil W.
4 link VG30 wagon, Stage 2 cams PP heads headers.
170 hp-180 tq
Call Doug at UP Motors, Tacoma, "engine swap elite"
datzenmike
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Re: Black smoke fixed now blue smoke

Post by datzenmike »

Pull the plugs. If one is black this could be the cause of the smoke. No need to medicate the other cylinders if so.

Any chance you are over filled with oil?
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
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chunstone
Posts: 373
Joined: 04 Nov 2007 09:12
Location: Wenatchee, Washington

Re: Black smoke fixed now blue smoke

Post by chunstone »

The engine oil level is one thing I thought about. I have been using the stock dip stick, unsure about the deeper pan and where the oil pickup tube is located. The pan was not a VG30.com or Teamtump. It had to be modified to fit the VG30.com engine mounting location so I believe that it was a custom one off pan. Something that I will be looking at is to see if smoke occurs with the oil level topped off.
Thanks for noting that.

Pulled the plugs and noted the condition of the tops of the pistons.
numbers 1, 3 and 4 were black and looked wet.
5 and 6 were dry looking.
number 2 was dry and black metallic looking.
I put Marvel Mystery oil in all cylinders and plan on letting the oil sit for 2 days. I put some old plugs back in finger tight. Will check and see if any of the oil has run down the cylinder walls
Plan on turning the engine over with the starter then pulling the old plugs and then put the new ones in.
Am I on the right track?
4 link VG30 wagon, Stage 2 cams PP heads headers.
170 hp-180 tq
Call Doug at UP Motors, Tacoma, "engine swap elite"
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thisismatt
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Re: Black smoke fixed now blue smoke

Post by thisismatt »

How much oil did you put in? You're a lot safer turning the motor over without the plugs in.
I'm your huckleberry.
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hang_510
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Re: Black smoke fixed now blue smoke

Post by hang_510 »

chunstone wrote: Marvel Mystery oil into the sparkplug holes after warming up and let sit 24 hrs. Do this 3 or 4 times if necessary. Add other solvents into the sparkplug holes,

Add Marvel mystery oil to the gas and the oil.
Before I try any of the above, do any of you have any ideas about unsticking oil rings in a VG 30 engine?
im a fan of MM (snake)oil. :twisted:
other stuff to try, in the plug holes, is Techron. saturate overnite.
last option IF its running right is Seafoam, but its not specificcly intended for stuck rings.

turn over with the plugs OUT! stand clear the stuff blasts out!!! :shock:

BOTH seemed to do a decent job even when i knew #3 (LZ24) was scored. #2 is the cylinder thats done now...(over rrrrrevvvvved :evil: )
byron wrote:I'd be all over that like a fat kid on a smartie.
okayfine wrote:Sense doesn't always have everything to do with it, and I speak from experience.
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chunstone
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Joined: 04 Nov 2007 09:12
Location: Wenatchee, Washington

Re: Black smoke fixed now blue smoke

Post by chunstone »

Well the marvel mystery sat for 24 hours and I did what all the nice folks said to do. Still have blue smoke so I'm going to run it for a while and see. Looking down the plug holes it looked like 3 cylinders were black and wet and 3 were dry.
I thank everybody here for pitching in.
4 link VG30 wagon, Stage 2 cams PP heads headers.
170 hp-180 tq
Call Doug at UP Motors, Tacoma, "engine swap elite"
datzenmike
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Location: Van. Isle.

Re: Black smoke fixed now blue smoke

Post by datzenmike »

Have you changed the oil??? It's likely half gasoline and thin enough to get past the oil rings.

Running super rich can wash the oil off the cylinder walls and cause ring wear. Running rich can carbon up the ring lands and not allow the rings to seat and flex properly. Your compression looks real good so this may not apply to the top two rings. The two oil control rings act like squeegees or windshield wipers, perhaps the oil scraper rings are plugged with carbon.

I would make sure you have fresh oil/filter in there and take it for a long ride. The detergent in it should slowly dissolve any deposits. As soon as the oil begins to darken, change it again. This won't happen over night and may take several oil changes.
"Nissan 'shit the bed' when they made these, plain and simple." McShagger510 on flattop SUs
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chunstone
Posts: 373
Joined: 04 Nov 2007 09:12
Location: Wenatchee, Washington

Re: Black smoke fixed now blue smoke

Post by chunstone »

Thanks, yes I did change the oil and plan on a long drive. I read that using synthetic oil would be better as it has more detergent in it. I will keep and eye on the color and change after a short time. Thanks again and I will keep you all posted as I'm excited to finally be driving it.
4 link VG30 wagon, Stage 2 cams PP heads headers.
170 hp-180 tq
Call Doug at UP Motors, Tacoma, "engine swap elite"
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