Using a spray lube may allow enough lube to get under the valve seal.  Short of pulling the head, you can try to lever up the valve spring and remove the retainer so you can get to the top of the guide to get some lube at it directly.  Rotating the engine so the piston is at the top of the bore will reduce the risk of the valve dropping completely out of the head.

The root cause for this has yet to be determined.  While the guides being on the tight side could be part of the problem and especially if the guides themselves are still iron, old fuel is typically the culprit in these cases.  After running for a bit, old fuel will leave a varnish or gummy deposit between the stem and the guide and will stick the valve within the guide once the engine cools.  This particular scenario happens more on the intake valves than the exhaust.  If the fuel is old (over ninety days) or smells bad, it needs to be changed out with fresh fuel before running the engine again.

My recommendation for vehicles that are not run very often is to always keep premium fuel (contains no ethanol) in the tank and keep the fuel level on the low side.  By keeping fuel levels low, the fuel within the tank can be turned over more frequently although not many miles are being driven.

It’s a relatively easy and a two minute check to verify exactly how much ethanol is in a given gasoline.  While I’ve found an excess of the labeled amounts of ethanol in the lower octane grades of pump gasoline, I don’t find any in the premium gasoline being sold in my area.  While it’s suppose to be a country wide mandate to not have any ethanol in premium gasoline, all I can verify for fact is it’s not in premium gasoline in my area.  I do end up doing frequent checks on my end to verify this simply due to using a considerable amount of pump gasoline on the dyno.  I get very constant results on the ~10% ethanol in 87 and 89 octane fuels but absolutely none in the 92-93 octane gasoline.

Here’s a picture of a commercially available ethanol tester but a tester can be made out of any kind of clear tube that’s gasoline compatible.

Daniel.  No reason to avoid it if that’s all you have.  And octane is octane so it really doesn’t matter what the fuel is as long as it keeps detonation at bay.  The ethanol laden fuels do have a propensity for the ethanol portion to drop out of suspension and the shelf life is reduced also.  I’ve found up to 30% ethanol in gasoline purchased from those stations that do not turn over their gasoline storage tanks very often.  The water attraction issue with ethanol laden fuels makes any moisture that accumulates in carbs and the rest of the fuel system a problem also.  All this reminds me of that old quote, “Other than that Mrs. Lincoln, how did you like the play?”.

But with all that aside, the major problem I have with ethanol laden fuels is consistency in the percent or amount of ethanol that’s in the gasoline.  For testing purposes, any variance in ethanol amounts makes for inconsistency in the air/fuel ratios when doing an above average number of dyno pulls where the engine is requiring more than a simple five gallons of fuel.  Nothing worse than have a combination sorted out and then a fuel change requires a jetting change in which to keep testing variables to a minimum.  In a street driven vehicle, this same inconsistency would be a tank to tank issue.  The 312 dyno mule with its 400+ dyno pulls on it would be a great example of why I would want some consistency in the fuel.  By simply testing with ethanol free gasoline, at least one level of inconsistency is removed from the equation.

If you’re not testing the fuel for ethanol content, you really don’t know what you have.  I can still get ethanol free premium grade gasoline at the pump but I’m finding that I must shop around for it now as the premium fuels are now starting to show up randomly in my area with some ethanol in it. And once the stations storage tank has been adulterated with ethanol laden fuel, it takes awhile to get rid of that even if subsequent loads of fuel have no ethanol.  The fuel tanker drivers tell me that the ethanol is added to the gasoline at the local fuel distributorships as the gasoline is ethanol free when loaded at the refinery.  The exception to this is where the refinery is in the same geographic neighborhood that the fuel makes its final sale.  There seems to be an issue with the ethanol dropping out of the mix when hauled for long distances which is why the ethanol is added closer to the point of sale and not necessarily at the refinery.  This then leads me to believe that this same ‘ethanol drop out issue’ can potentially take place to some degree in your daily driver vehicle.

Hutz.  Ditto on the fuel consistency.  The jury is still out here on whether gasoline or ethanol makes the most power.  I’ve done repeated tests on the dyno for customers with both and it all hinges on the carburetor on which does the best.  If limited to pump gasoline and a 91-93 octane level, then alcohol is the obvious choice for high compression or boosted engines but once the gasoline octane is matched to that of alcohol, then alcohol no longer has that particular advantage.