My engine was fully redone about 4 years ago and has approx 10,000 miles on it. Since day 1 it has always liked to blast out a nice cloud of oil smoke only on HOT restarts if it sits for say 20 minutes or so. If it does not sit very long then there is zero smoke. Compression and leak down tests are all good, it runs amazing. Every 3-4 tanks of fuel I will add maybe a 1/2 quart of High Zinc VR-1 Racing. No leaks, perfect tune AFR is on target, PCV system in tact and functional etc. Engine is a .040 425 that was sonic checked, torque plate bored/honed after 3 holes were sleeved. New rods, pistons, valves all from Centerville and TA Performance. Ported "Doc Mod" intake, modified Edelbrock 1407 750 CFM carb, CB Performance Black Box 3D programmable ignition system, rebuilt stock distributor with vacuum advance removed and mechanically locked out, TA chrome shorty headers, 2.5" mandrel bent exhaust from TA that I redesigned to locate mufflers to rear, AEM UEGO AFR monitor/guage/datalogger outputs etc, ST-400 rebuilt and modified by me, Hughes 2000 RPM stall, stock 3.07 gears, Cam is a modified version of the smallest Thumper cam with a 109 LSA vs 107 and a bit more lift. Idles in neutral around 15.5 " Hg and in gear around 11-12" Hg. Heads were done with new valves and springs, guides all done to spec not bronze. A friend of mine had the heads done before I purchased the car from him so I am not 100% certain what was done with the guides exactly. The short block was done at a different machine shop. From what I have read Buick never used seals as they felt some oil lubing the guides was a good thing. Has anyone used seals on these? Intake only? or done both intake and exhaust?
When I rebuilt my 401 I installed new guides and no seals and I am living with the same smoking problem as you. At least I’m not worrying about guide wear. You said you have a programmable ignition system does that mean there is a computer that advances the timing when cruising like the factory vacuum advance does? How about at idle? Mileage will suffer if you don’t have the extra advance when cruising at part throttle.
My Riv will do the blue smoke puff about every 20th start or so, hot or cold. Has seals on the intakes but not on the exhaust. Seems to be common, not anything to worry about, and it makes sense that we get some smoke when we don't run valve seals. It is quite embarrassing, though, when you fire up a really good looking car and it looks like a pile to most people because it smokes on start up. I'm running 15w40 Rotella oil, and it definitely helped over the 10w30 that was recommended and what I was running at first.
Yes, It is a CB Performance Black Box This ignition computer and coil driver Box has a 5 BAR MAP sensor in it that references engine vacuum or boost and electronically controls advance (or retard). Its interface is similar to using HP Tuners or EFI Live. I can accurate plot the timing to do whatever I want +/- 70 degrees across the entire span of RPM and loads. No more screwing around with weights, springs, advance limiters, or adjusting vacuum advance servos etc. I simply plug into a hidden jack inside my glove box with my laptop and I can see everything I need and modify the spark map as needed. 3D means we can plot the spark value across an X,Y axis with X = engine vacuum and Y = RPM.
Exactly! I feel like a bum so I wait to fire it up until people have walked away or closed their doors etc in a parking lot, such as in front of Starbucks. I do not wish to fill someones car, eyes, or children with my "Oil Cloud of Death" My paint job being a total crap 1970's respray does not help my appearance any. So to the untrained eye it probably looks like an old broken down car that barely runs. The other worry is that I installed catalytic converters on mine which was the best move ever. Oil kills catalytic's fairly quickly. I no longer smell like old tailpipes after driving the car. This rat piss they call gasoline aka 93 Octane reeks when burned without cats. Smells fine on race fuel but no way am I paying for that just to cruise around with. I drive this car quite a lot.
Buick started installing intake seals in the 1966 model. They offered a seal kit through the parts dept to be retrofitted to earlier models but the valve guide towers had to be cut to accept the seals. There was a very simple tool to do so but I have not actually done so myself so cant comment. I see the kits frequently for sale as NOS parts. Any visible blowby from your valve cover if you pull the breather while the engine is up to temp and running?
Yes sometimes very faint but nothing “pumping” out. It’s an Edelbrock chrome breather not tied back to the air cleaner. No oil or anything drips or gets onto the valve cover. That is what bugged me and prompted my leak down test.
Original stock rocker assemblies just "ooze" oil from the top when running. The rebuilt ones I got had bushings installed and channels cut that added more oil to the top, resulting in a shower of oil (lots of startup smoke and on acceleration after coasting). Adding seals on intake and exhaust is the only fix.
The website below suggests worn rocker arms or rocker shafts fitted upside down as possible causes. http://centervilleautorepair.com/tech-info/excessive-oil-consumption-causes
My nailhead has done this one time. It was a warm day, stopped at the Publix, grabbed a few items, (so, about 20 minutes) and looked like an F-4 doing a cart start. Only once, in several years and 5k miles.
