| Author |
Message |
geoffwestmore
Samba Member
Joined: April 07, 2008
Posts: 95
Location: Australia
|
 Posted: Tue Apr 29, 2008 8:29 pm Post subject: smoke from exhaust when starting (sometimes) |
 |
|
About once in every 20 times when I start my stock 1600 DP a small cloud of blue (oil) smoke comes from both exhaust pipes.
The car is parked on level concrete overnight.
I use Castrol 15W40 which I change evry 3,000 miles.
The engine burns a negligable amount of oil.
My compressions are all 130 - 140 on warm engine.
Oil pressure is 60 psi cold, 40psi after 10 mins at 45 mph and 18 psi at idle when hot.
The heads and valves are 6 months old.
The crankcase ventilation seems normal with no excessive pressure at the oil filler cap, the generator stand baffle is correctly fitted and the vertical breather on the oil filler is clear with the rubber extension fitted.
The valve covers are stock and not vented.
Could anyone suggest what might be causing the oil getting into the combustion chambers . Thanks, |
|
| Back to top |
|
 |
timsvw
Samba Member
Joined: September 07, 2004
Posts: 286
|
| Posted: Tue Apr 29, 2008 11:08 pm Post subject: Re: smoke from exhaust when starting (sometimes) |
|
|
| geoffwestmore wrote: |
About once in every 20 times when I start my stock 1600 DP a small cloud of blue (oil) smoke comes from both exhaust pipes.
The car is parked on level concrete overnight.
I use Castrol 15W40 which I change evry 3,000 miles.
The engine burns a negligable amount of oil.
My compressions are all 130 - 140 on warm engine.
Oil pressure is 60 psi cold, 40psi after 10 mins at 45 mph and 18 psi at idle when hot.
The heads and valves are 6 months old.
The crankcase ventilation seems normal with no excessive pressure at the oil filler cap, the generator stand baffle is correctly fitted and the vertical breather on the oil filler is clear with the rubber extension fitted.
The valve covers are stock and not vented.
Could anyone suggest what might be causing the oil getting into the combustion chambers . Thanks, |
Bad oil rings and/or worn-out pistons and/or glazed cylinder walls and/or crankcase overfilled. |
|
| Back to top |
|
|
towd
Samba Member
Joined: June 20, 2005
Posts: 2458
|
| Posted: Tue Apr 29, 2008 11:15 pm Post subject: |
|
|
| valve guides are getting worn |
|
| Back to top |
|
|
67jason
Samba Member
Joined: August 28, 2005
Posts: 4741
Location: behind my back feet - Pittsburg CA
|
| Posted: Tue Apr 29, 2008 11:30 pm Post subject: |
|
|
i agree the valve guides are the likely culprit here. if your heads truely are 6 months old, whoever rebuilt them did a shitty job installing the guides....or didnt replace them durring the rebuild.
_________________
67 bug x3
67 ghia
64 bug |
|
| Back to top |
|
|
miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
|
| Posted: Wed Apr 30, 2008 12:03 am Post subject: |
|
|
I don't know about you guys, but when I pulled the heads to recase the 1915 turbo there was a little oil in all 4 cylinders. They only had at most 500 miles since first start, so I kinda figured it was normal; most likely due to the flat design of the engine I figured. It almost always makes a little 'puff' at first start, but after that it's gone.
_________________
Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
|
|
| Back to top |
|
|
nextgen
Samba Member
Joined: August 19, 2004
Posts: 6151
Location: CONGERS, N.Y.
|
|
| Back to top |
|
|
BugMan114
Samba Member
Joined: March 22, 2007
Posts: 3744
Location: Ellenwood, GA
|
| Posted: Wed Apr 30, 2008 2:51 pm Post subject: |
|
|
Damn, i was always wondering about that. But why will it only do it about every 20 times? WHat causes it to only occur every 20 times? What in the engine "changes" once every 20 times? Help me to understand this.   . Does oil build up somewhere, and just unload in the cylinders after about 20 times, or what?
_________________
1974 Super Beetle: Custom resto in progress
1972 Super Beetle: Daily Driver
1971 Std. Beetle w/ 1929 Mercedes Benz Gazelle kit
1960 Baja Bug
1969 Baja Bug
Sand Rail- Homemade
Sand Rail- FUBAR
Aircooled Airheads
Why the hell do they call it a gland nut. its obviously a big fat bolt!!! |
|
| Back to top |
|
|
miniman82
Samba Swamp Donkey
Joined: March 22, 2005
Posts: 9515
Location: Southern Maryland
|
| Posted: Wed Apr 30, 2008 5:00 pm Post subject: |
|
|
Probably has something to do with the amount of time the car is left sitting, because the longer it sits the more the oil seeps past the rings. The best you can do is make sure the rings are aligned correctly as per the manual, and seat them as good as you can.
_________________
Build thread: http://www.thesamba.com/vw/forum/viewtopic.php?t=212747
| Glenn wrote: |
| satterley_sr wrote: |
I just wanted to bitch but I'm getting no sympathy. |
Welcome to the Samba. |
|
|
| Back to top |
|
|
koolkarmakombi
Samba Member
Joined: June 26, 2007
Posts: 238
|
| Posted: Wed Apr 30, 2008 6:56 pm Post subject: |
|
|
| BugMan114 wrote: |
| Damn, i was always wondering about that. But why will it only do it about every 20 times? WHat causes it to only occur every 20 times? What in the engine "changes" once every 20 times? Help me to understand this. . Does oil build up somewhere, and just unload in the cylinders after about 20 times, or what? |
sun spots, ouiji boardsand sectors of the moon combine!
My fasty did that about the same frequency. It had an all new engine with tight valve guides etc.
They just do that sir!  |
|
| Back to top |
|
|
nextgen
Samba Member
Joined: August 19, 2004
Posts: 6151
Location: CONGERS, N.Y.
|
| Posted: Wed Apr 30, 2008 8:42 pm Post subject: |
|
|
Ha I like the Sun Spot!!! Serious, I think it may have something to do wh how and when the engine stops and I do believe for sure is you let the car lay for a long time the oil will get into the cylinders and burn off on a start. But it has happened to me on a 5 min drive on a saturday to the bagel barn for some bagels and coffee. I shut the engine and less the 5 minutes later, start it and James Bond Smoke screen appears.
We know it is oil in the cylinder, so maybe on the shut down oil is sucked in and not burned or maybe it is not just oil but extra fuel that did not burn on shut down. Yep sound more like it. THen you start and burn it. Which would explain why only at times it happens. Like when you shut you car it is keeps running, dieseling. If you get a good clean shut down it don't happen.
Can't confirm any of that so still holding on to the Sun Spots.
_________________
email: [email protected]
The TYPE IV UPRIGHT CONVERSION MANUAL
BEETLE MAGNETIC DEFLECTOR SHIELDS
LETS TALK DUBS https://www.youtube.com/results?search_query=joe+cali+ghia https://letstalkdubs.libsyn.com/ep-200-joe-cali-ty...qI3xJTCzjs |
|
| Back to top |
|
|
geoffwestmore
Samba Member
Joined: April 07, 2008
Posts: 95
Location: Australia
|
| Posted: Thu May 01, 2008 11:28 pm Post subject: smoke from exhaust (sometimes) |
|
|
thanks for your advice. I was referred to the Rob and Dave article "Burning Oil" in another forum. It all made sense and it has convinced me to try SAE30 oil next change . I will report back soon.
See www.vw-resource.com/burning oil |
|
| Back to top |
|
|
VSarge
Samba Member
Joined: March 31, 2008
Posts: 367
Location: St Louis, MO
|
| Posted: Fri May 02, 2008 5:43 am Post subject: |
|
|
Motorcycles with flat motors will do this and it depends on the position of the low cylinders (what portion of the stroke they're on) and causes no problems whatsoever.
Sarge
_________________
_________________
VW trike -- FrankenMutt
1971 1600
Swing Arm frame
Stock 4 spd tranny - no reverse gate (crap!)
1966/67 rear brakes wheel cylinders from front of 1966 Bug
1934 Chevy headlight
Custom leading link front end
Ford Ranger rims
P225/60R15 rear tires
GoldWIng front tire
Body is fiberglass nose from semi
One ugly exhaust, heavily rusted, set up for heat??? On a trike?? |
|
| Back to top |
|
|
|
