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MGB Smoking MGB

daver80

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Hi all! I've got a 66 MGB that has been sitting for about 2 years without running. No real problems, just got sidetracked with other stuff (translated- kids) Had been running great last time she ran. Engine, head, have about 15,000 miles since rebuild. Put 5 gallons of fresh gas in, changed the oil, charged the battery and she started right up (with choke, of course) She smoked badly at first- white smoke, not as much later. thought it would clear, idled about 10 minutes after I shut off the choke (jets stick a bit, have to push them in after engine is warm). Seemed to idle fine but still too much white smoke. I cleaned out the barrels in the SU's- they werent dropping properly ("clunk") I checked my oil- no coolant in oil- looks fine, checked plugs, look sooty black from running with choke on, but not oil fouled. Any suggestions before I dig into checking the lifters under the intake and exaust manifolds. Maybe I should just let it run longer to burn more of the old gas out of there? Opinions? Thanks!!! Dave P
 
Two words: OLD GAS!

Don't look for somethin' wot ain't there. Get it thru several "heat cycles" (up to normal temp) before making any decisions.
 
Doctor- Thats good advice I really didnt want to go poking around too much- she ran so nice last time I drove her. I'll try running more ogf the gas out of her.

We owned an 84 300D for 8 years, sold it in 2004 with 230k. Ran like a top. is yours light metalic blue? Dave
 
Why, yes it is. Beast has well over a quarter on 'er, still putters along at 80 when asked. Took 'er on a 400 mile round trip this past weekend. Not a hiccup. Diesela's a good ol' girl. Bit "beamy" for my taste but <span style="font-weight: bold">strong</span>.

..."Brunhilde" wouldn't fit on a license tag.... :jester: :devilgrin:
 
maybe you just have moisture in the exhaust system?
 
Let er run and then change the plugs. I picked up a Bimmer recently, drained the gas and fired it up after a 5 years slumber. White smoke for a very long time and had me concerned. After running it for a good bit, she's fine. Bad gas and water in exhaust is what I attest it to.
 
Give it 20 miles or so. My 73 smoked a bit at first and leaked oil like a sieve after not running for at least 8 years. After about 20 miles the smoke was gone and the oil leak slowed down to a silver dollar size puddle after being parked over night.
 
I think I'll back her out, fire her up, air her up and let her run her a bit. Sounds like no need to panic just yet. Thanks!! Dave

not quite as glamorous a list:
66 MGB
67 IH Cub Cadet 122
86 BMW R80RT (110k bike)
89 Volvo 240 wagon (206k)
and an old 70's snowblower
 
Does a 66 have that crankcase breather PCV valve? If the diaphragm cracks on this you can pull oil into the intake and get lots of white smoke, back in college I had a head rebuilt on my MGB before I figured that out!
 
Glemon- I'll check that out. All she has for emmissions is a disk shaped thing up on top with about 2 inches of tube. The plugs were sooty, but not oily. so I dont think oil is going into the combustion chamber, but I'll check that round thing- easy enough to do. Had it out twice now and still smokes. But I did get my turn signals working! Dave
 
That disk shaped thing is what Glemon is on about. The wire "spring" widget holds the cap in place, under it should be a spring and a diaphragm with a small "billet" valve vulcanized to the center. The diaphragm should be flexible and unsplit, the funnel underneath clean and free of carbon deposit.
 
Dr / Glemon- I opened the disk (breather) tonight and saw a trace of oil in there, not a lot, but it was in there. The rubber wasnt cracked, but it wasn't new, soft and suple either. Those diaphrams are probably more $$ than I'm expecting, but maybe I should give it a try. At least price it out. Might even be a NAPA item- i might be suprized. Thoughts? Dave
 
I doubt you'll find one of <span style="font-style: italic">those</span> at NAPA. If it has no cracks and isn't brittle it should be fine. A trace of oil is normal too. Run it some more. My vote is still on old gas. Run what's in there out and refuel. Then see if the smoke clears.
 
That 2-inch thing on top is, in fact, the pcv valve mentioned earlier. You can undo the hose at the bottom of it, and check for oil in the hose; if it's oily there is a good chance the diaphragm is cracked. Another possibility is some rings stuck from sitting for two years; they 'may' free up after some more driving.
 
Or soaking them overnight(combustion chamber fill) with GM Top End Cleaner. Works great at getting the carbonbuildup off of rings.
 
Everyone who posted- BAD GAS! drained it all out the $2.23 gas (from 2 years ago)and refilled with $4.23 gas- and all is well (except for the $4.23 part) Dave
 
mehheh. :laugh:
 
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