

| Subject: | Re: Intermittent smoke after stop signal wait... |
| From: | Don Hanson |
| Date: | Sat, 19 Oct 2013 17:24:34 -0700 |
Now that I hear back from everyone, it just may be the valve guide seals, or the guides themselves, or both. I recall when I swapped in a slightly 'performance' cam and also when I moved the head over to my current block...something about the valve stem seals....trying to 'make' a spring compressor to remove the valves and then giving up..it is probably time for a reworked head soon anyhow...lottsa miles piling up on this head I have been using, untouched pretty much, since I got the van about 60k miles ago. I see them listed, rebuilt with new valves and everything for around $275..that ain't too bad. Maybe next spring...thanks all Don Hanson On Sat, Oct 19, 2013 at 3:36 PM, Scott Daniel <scottdaniel@turbovans.com>wrote: > is it blue are black smoke ? > > Worn guides or valve seals is what I'm suggesting right now. > > you're not running a cat. > I think that most cars, like 80's and forward, with 02 sensor and cat can > burn oil 'nicely' and not smoke .. > in that the 02 is helping adust perhaps ...for oil burning in the > cylidners ... > and the cat cleans it up. I've seen cars that use a qt of oil in 500 to > 1,000 miles and never smoke at all. .. > perhaps lack of a cat is a factor. > I like to have at least looking like it has a cat, since having one on a > gasoline van of that year was stock in all 50 states. > > I4 VW engines were well known for valve seals and /or worn valve guides. > > > On 10/19/2013 9:21 AM, Don Hanson wrote: > > I sometimes see a nasty grey cloud of smoke from the exhaust of my 84. > Digifant EMS on an inline VW motor. I am guessing it may be a faulty > throttle switch that sometimes goes to 'full rich' for whatever reason. By > intermittent I mean....When I go to town, perhaps 1 trip of four, this > smoke shows up. It doesn't smoke at every signal....It may do so for two > in a row, then no smoke at all the rest of the driving around. It > sometimes even smokes breifly on start up, but very seldom... > > Here are the specifics of how this occurs and when: It normally happens > in the city when I am stop and go driving or hitting traffic lights. > Everything might be normal without any problem then I will roll up to a > signal and idle there while the light cycles then as I leave, the van puffs > out an embarrassing cloud of grayish exhaust smoke, lasting perhaps two > seconds before the exhaust clears back up and is again invisible. I have > also noticed that on start up, then coasting down a longer hill the exhaust > will backfire....I do have an air leak in my exhaust system which probably > allows air in to make the loud bang more likely... > > I see no smoke on long hill descents. Nothing when I redline the motor > to 6000rpm. I don't burn much oil for a VW inline, but I do have a slight > leak at my homemade filler when I park with the nose up on a steep > incline...a quarter sized puddle below maybe. > > I think my throttle switch is NLA...I think it is the longish leaf > springy looking type...It seems to click correctly with linkage movement > and it clicks off when the throttle is closed...when I do it in the engine > by hand...consistently and correctly.. > > Anybody have any other ideas about this stinky cloud of smoke I sometime > see? I hate puffing that into our air, though it's probably nothing > compared to, say, a coal fired power plant...a minor 2-second visible > exhaust puff a few times a week... > > > >
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