Topic: Shit (Read 23478 times)

patsmx5 · « **on:** October 28, 2009, 12:39:51 PM »

When I parked my car this morning, I noticed a cloud of blue-smoke coming from behind the car. Pretty bad too.

Runs perfect though. Guess I'll be doing a compression test soon. Might be building an engine sooner then anticipated.

Joseph Davis · « **Reply #1 on:** October 28, 2009, 01:29:09 PM »

Fucking SWEET.

Now you get to build the fuck out of it.

Teg2boo · « **Reply #2 on:** October 28, 2009, 04:14:46 PM »

My cars are smoking badly on very cold days. I don't know if this one will smoke. I hope not. It's kinda embarrassing when ppl look at you with their "WTF" face.

patsmx5 · « **Reply #3 on:** October 28, 2009, 04:18:20 PM »

Well, before I turbo'd it the compression was 185 on cylinders 1 and 4, 165 on cylinders 2 and 3. A leakdown test showed the exhaust valves leaked a spec on cylinder 2&3.

Just checked the compression after 10 months of boost. Hot engine, all the plugs were out during the test, throttle wide open.

Compression looks Ok to me. Plugs are black from runing a cold plug rich, but they otherwise look fine.

So, wtf would make it smoke so bad? This morning I was letting the car idle a few minutes and saw a cloud of smoke from the corner of my eye. I almost reached for the fire extinguisher till I realized it was blue-smoke. Got out, and sure enough it was coming from the exhaust pretty bad. Rev'd it up and it blew a good bit out, and sorta cleared up some. I just killed it and went to class.

Then when I got out of class I fired it up, no smoke. Drove it some, no smoke. Boosted the shit out of it, no smoke. Now it's not smoking at all.

Joseph Davis · « **Reply #4 on:** October 28, 2009, 04:27:54 PM »

7's are not cold for your setup. You either had an atomisation problem, or much more likely based off of how sooty the ground strap and the well is you were running way too rich. How did you log your wideband when tuning?

patsmx5 · « **Reply #5 on:** October 28, 2009, 04:32:56 PM »

I'm using a LC-1. It's tuned pretty rich. 13:1 at 100kPa absolute tapering to 12:1 by 150kPa, then 11:1 by 170kPa and I'm running 200kPa, or 15 PSI boost. The megasquirt logs the wideband through MegaTune. Running RC engineering 550cc injectors FWIW.

Joseph Davis · « **Reply #6 on:** October 28, 2009, 04:45:37 PM »

So you logged the LC-1 through the MS box via MegaTune? Given your history of ground problems, I daresay your tune is richer than you think it is.

You might have gassed your oil, making it super thin + prone to burn. Check that first, then retune quick before you go hammering on it.

SloS13 · « **Reply #7 on:** October 28, 2009, 04:50:45 PM »

changed my miata's oil a week ago. Smelled like straight-up fuel. Finally got around to fixing *most* of my rich spots.

Joseph Davis · « **Reply #8 on:** October 28, 2009, 05:03:50 PM »

You two need to date or something.

patsmx5 · « **Reply #9 on:** October 28, 2009, 05:14:10 PM »

It's been a while since I compared the LC-1's serial output two the one displayed in Megatune, but last time I did, they were within 0.1 AFR. I believe all my grounding stuff is correct.

Oil appears normal, doesn't smell of fuel. It's got about 10k/ 10 months on it. I was planning on changing it at 12K.

Also, just pulled the hose off the inlet and outlet of the turbo. No signs of oil at either inlet or discharge, and zero shaft play on the turbo.

92CXyD · « **Reply #10 on:** October 28, 2009, 05:27:24 PM »

What about pushing oil out of the crankcase?
Do you use an oil catch can?

Robb · « **Reply #11 on:** October 28, 2009, 05:36:55 PM »

Pat, what oil/weight are you running?

patsmx5 · « **Reply #12 on:** October 28, 2009, 05:40:04 PM »

Valve stem seals were replaced with FelPro fancy high quality valve stem seals about 2 years ago when I had the head off fixing a blown headgasket from my own stupidity.

I don't have a catchcan. The PCV valve just has a short piece of hose hooked to it that dumps to atmosphere, and a small filter hooked onto the breather. So even if there was excessive crankcase pressure, it would just blow oil into the engine bay, which it is not doing.

EDIT: running Mobile 1 10w-30 synthetic oil and a mazda oil filter. I suppose I could change the oil and filter.

92CXyD · « **Reply #13 on:** October 28, 2009, 05:50:22 PM »

Change the oil and the filter would be a good start.

Could be as simple as oil being too saturated with soot/dirt/fuel and causing the rings to not seal fully.

On most turbo/supercharged engines you should change the oil more often than the recommended OEM spec.

On my Supercharged Previa I have to change the oil every 7.5k miles even though I have a 7qt. oil pan and a 2 qt. reserve.

Maybe through some detergent in your oil to help clean the sticky rings.

After about 500miles on clean oil those rings should seal better and your compression will go up. ;D

Robb · « **Reply #14 on:** October 28, 2009, 05:53:15 PM »

Quote from: patsmx5 on October 28, 2009, 05:40:04 PM

Valve stem seals were replaced with FelPro fancy high quality valve stem seals about 2 years ago when I had the head off fixing a blown headgasket from my own stupidity.

I don't have a catchcan. The PCV valve just has a short piece of hose hooked to it that dumps to atmosphere, and a small filter hooked onto the breather. So even if there was excessive crankcase pressure, it would just blow oil into the engine bay, which it is not doing.

EDIT: running Mobile 1 10w-30 synthetic oil and a mazda oil filter. I suppose I could change the oil and filter.

I wouldnt put the new mobil 1 formula in any of my cars. Google API standards and school yourself on zinc content and detergents. Not sure where you live, but I dont run anything lighter than a 40 weight in my turbo cars. Not saying any of this is your problem, but Ive been doing alot of oil research lately and have made myself paranoid lol.

patsmx5 · « **Reply #15 on:** October 28, 2009, 05:59:26 PM »

Well, I'll change the oil this weekend I suppose. I guess after driving it for a week or two on clean oil I'll do another compression test just to see if it makes a difference. I kinda don't think the rings are bad though, as when I did a leakdown test before turbo'ing it I got virtually no leakage through the rings. Factory spec is 185 PSI on this engine, and it's got 150K on it, 10K with boost, and had about 14 bottle of nitrous through it before the turbo. If I had my leakdown tester with me I'd do that again just to verify the rings are good, but I don't have it right now.

EDIT: And yeah, I've done a little reasearch on oil and my next oil will be walmart's Super-tech synthetic. Supposed to be good synthetic oil for 12 buck/ gallon.

And I live in MS, so it doesn't get too cold here. Maybe 10 days where it drops below 32 in a year.

92CXyD · « **Reply #16 on:** October 28, 2009, 06:06:29 PM »

Quote from: Robb on October 28, 2009, 05:53:15 PM

Quote from: patsmx5 on October 28, 2009, 05:40:04 PM
Valve stem seals were replaced with FelPro fancy high quality valve stem seals about 2 years ago when I had the head off fixing a blown headgasket from my own stupidity.

I don't have a catchcan. The PCV valve just has a short piece of hose hooked to it that dumps to atmosphere, and a small filter hooked onto the breather. So even if there was excessive crankcase pressure, it would just blow oil into the engine bay, which it is not doing.

EDIT: running Mobile 1 10w-30 synthetic oil and a mazda oil filter. I suppose I could change the oil and filter.

I wouldnt put the new mobil 1 formula in any of my cars. Google API standards and school yourself on zinc content and detergents. Not sure where you live, but I dont run anything lighter than a 40 weight in my turbo cars. Not saying any of this is your problem, but Ive been doing alot of oil research lately and have made myself paranoid lol.

I agree I found that if you want synthetic try some Royal Purple or Valvaline Syn. or Valvoline reg. make sure API SM or higher.

I remember reading something about looking at the tightest bearing clearances you have and for every 0.0015" you go 10 up on the oil grade scale. And this is where you start for the minimum oil thickness.

Remember "w" after the number means how it flows when cold and the second number is the weight/flow characteristics it has at engine temp.

Joseph Davis · « **Reply #17 on:** October 28, 2009, 06:09:53 PM »

Rotella T 15W40 for life.

patsmx5 · « **Reply #18 on:** October 28, 2009, 06:53:20 PM »

I run rotella in my trucks, but not the miata.

HiProfile · « **Reply #19 on:** October 28, 2009, 07:13:32 PM »

187/165 would be 13%, ideally you'd be at 5-10% variance. Not the best, but it's an abused old motor, by the low standards Miata probably intended for it.

Bad rings lead to a clear-blue smoke while driving, and half-burned oil leads to white-blue smoke. Unburnt particulate oil is sooty black like gasoline. As mentioned before, it's probably some leaky exhaust valves or a slight leak from your turbine. That would lead to whitish oil after sitting for a while, since it would sloooowly leak out.

Just beware that moving to synthetic can make a plugged-up (sludgey) bad seal unplugged, and leak. Its very uncommon, but it can happen. It doesn't like to mix with impurities, and tends to sweep that sludge into the pan bottom. If you change oil regularly and don't have leaks now, you probably won't have them later.

patsmx5 · « **Reply #20 on:** October 28, 2009, 07:20:08 PM »

Yeah, funny thing is this engine doesn't use oil. It's got 10K on the oil now, and it's used about 4 oz in the last 2K miles. Since Last December when I changed the oil, I've added a total of less then 1/2 a quart to it. And I've been running synthetic for 2-2.5 years now. FWIW, it was a white-blue smoke.

I guess it could be the valve guides on the exhaust side, as I know the exhaust valves leak a spec on cylinders 2 and 3.

Urban Indian · « **Reply #21 on:** October 28, 2009, 08:31:07 PM »

fyi i didnt read

but WTF how long have those plugs been in there?

patsmx5 · « **Reply #22 on:** October 28, 2009, 08:34:05 PM »

They've been in for 5-6 months/ ~5K miles.

Eggylshatch · « **Reply #23 on:** October 28, 2009, 09:53:11 PM »

why are you waiting so long to change your oil? I don't give a fuck if its synthetic or not, that shit breaks down and accumulates foreign particles in it.

sewell94 · « **Reply #24 on:** October 28, 2009, 11:55:08 PM »

Quote from: Joseph Davis on October 28, 2009, 06:09:53 PM

Rotella T 15W40 for life.

quoted for truth, i know quite a few 7 sec cars that run it.

xsenceo89x · « **Reply #25 on:** October 29, 2009, 12:04:15 AM »

im an idiot

Eggylshatch · « **Reply #26 on:** October 29, 2009, 12:17:21 AM »

Quote from: xsenceo89x on October 29, 2009, 12:04:15 AM

Damn are you sure youre not leaking it from somewhere? lol 4 quarts that quick? try gear oil or somthing really thick

nurrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrrr

Pat, you're turbo'd aren't you? Have you checked your turbo? When my turbo was dying it would leak oil into the exhaust, but it would only be noticeable after stopping and idling for a bit and then you would see smoke when accelerating/revving.

HiProfile · « **Reply #27 on:** October 29, 2009, 10:42:21 PM »

Quote from: c0mpl3x on October 28, 2009, 11:11:45 PM

and it's mobil 1

Last long-term test I saw even with that stuff still didn't support 10k milage, let alone 6k. It's viscosity changed enough to impact fuel milage, and viscosity change will also affect the amount of protection it provides. It also chemically showed signs it was breaking down. By chemically, I mean they sent oil samples ever 1k miles to a lab that tests people's race oils from 0 to 10k miles.

patsmx5 · « **Reply #28 on:** October 29, 2009, 11:14:10 PM »

Yes it tubo, new GT3271 10 months old/ ~10K miles on it. zero shaft play, no signs of oil in the compressor discharge. But yeah, it could have been through the turbine. Strangely it has not done it again.

Robb · « **Reply #29 on:** October 31, 2009, 12:05:07 PM »

Quote from: HiProfile on October 29, 2009, 10:42:21 PM

Quote from: c0mpl3x on October 28, 2009, 11:11:45 PM
and it's mobil 1

Last long-term test I saw even with that stuff still didn't support 10k milage, let alone 6k. It's viscosity changed enough to impact fuel milage, and viscosity change will also affect the amount of protection it provides. It also chemically showed signs it was breaking down. By chemically, I mean they sent oil samples ever 1k miles to a lab that tests people's race oils from 0 to 10k miles.

I had a stock pile of the old Mobil1 15w-50 ive been running in the Porsche, but im about to run out and need to make a decision. Probably gonna be Rotella truth be told. I change oil/filter every 2500 and cant justify redline or royal purple in it.

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Author Topic: Shit (Read 23478 times)