Sticking valves

[mpohrille]

1976 A$ FWC, Electronic ignition. a4 Starts well. RPM wonders while it warms up. It runs great at cruising rpm (2000-2200 ) but when u slow it down (less then 1800 it misses and I can hear popping in the exhaust when it misses. I have had this problem in the past and it was diagnosed as sticking valves. At that time I put some MMO in the crankcase andit cleared up. This time this has not worked. Any other thoughts?

[sastanley]

Hi,

for sticky valves, I remove the spark plugs and use a squirt style oil can (with MMO) and squirt some into the top of the cylinders. I immediately rotate the engine (hand crank if you got it, or blip a few revolutions with the starter) to move it around, so it hopefully drips down the valve guides and frees those sticky valves up. I let it sit for a day and come back and try it.

If I know I am laying the motor up for weeks/months, and I have the time, I try to remember to do this after I run her to avoid the sticky valve problem a month from now when I want to restart it.

[tenders]

I put MMO in the fuel for sticking valves. I think it’s an ounce every five gallons - actually I keep my MMO in a recycled Sta-Bil bottle these days because it has the cool one-ounce metering system attached.

[sastanley]

tenders, yeah, I do too..I don't measure it though. I put a splash in every time I add fuel. It probably comes out at 100:1 or so..

[sdemore]

When two of my intake valves stuck open, I tried putting MMO in through the spark plug hole, but it just ran straight through the open valve and out the carb. I took off the valve cover plate and sprayed Seafoam Spray on the valve stems. In 2 seconds, everything was clean and free.

[Dave Neptune]

The best way to lube sticky valves is with a spray into the cylinder or via the fuel at a 100:1 mix or about 1 1/4 oz's per gallon.

The fuel goes past the valves for excellent delivery if you can get it to run. The problem with pouring it into the cylinders is it is way to much oil and can cause a very hard start and the oil may not get to a valve stem. Turning the engine with the starter and using a spray will get the oil to the VALVE STEMS. Squirt into the intake (easy with the carb off and through the plug holes.

I ran TCW-3 at just over 150:1 about 70% of the time I ran her for 34 years and never fouled STANDARD plug!!! And never had a sticky valve on my A-4 that was purchased as a worthless frozen dead weight in the boat however a bit of patience and I got it to spin for another 34 years.

Dave Neptune

[mpohrille]

tnx for all the great advice I will be trying them and give feedback. I particularly like the idea of taking the valve cover off an spraying