Massive Coronary only Minutes from the Marina

Jake N Eggs · Jun 12, 2012

Another possibility is stuck valves due to the crap gas that we have now. Have seen the valves seize on a rebuilt Austin Healey with 10 hours on the engine. Car sat for a couple of years and the old gas caused shelac or something to seize the valves. This is OHV interference engine and bent the valves and push rods. Pretty shocking to see. We use lots of Stabil now on the vehicles that don't run much.

Ray Bowles · Jun 12, 2012

After having rebuilt probably 500+ engines in my life I'll offer my 2-bits. A gas burning engine must have:
1. Compression
2. Spark at the plugs at the proper time.
3. Fuel delivered thru the carb.
Engines can suffer massive internal failures without noise. Broken camshafts and broken timing gears or chains all can cause loss of compression without noise. A head casket failure is very low on the list of possible causes.

Before all else you need to do a compression check on all cylinders. If there is no compression on more than 1 cylinder stop here and check distributor for rotation. If the rotor turns then use a flashlite and look thru a sparkplug hole and see if the piston goes up and down as you turn the motor over by hand. If you can't do that then use a soft but somewhat ridgid piece of wire to place in the sparkplug hole and with the distributor cap off slowly turn the engine over by hand and see if the wire goes up and down. You must hold the wire in your hand during the entire process so you might need a helper. If the wire binds up then STOP rotating the motor so you don't bind the wire in the engine.
If you find that the pistons are not moving you have had a fatal heart problem.
If you have rotation of the pistons and rotor but no compression then check valve lash adjustment.
If the valves do not go up and down as you turn the engine over to set valve lash then the camshaft is broken. Engine is toes pointing skyward....dead. If lash is OK, pistons go up and down and rotor goes around in proper time with the pistons and you still have no compression then the motor is worn out. Also considered a fatal flaw.
You know there is fuel getting in the motor so I'll not go there. I think you can figure out your problem with these tests.
Good luck, Ray

RichH · Jun 13, 2012

The best way to assay if the valves, usually exhaust valves, are stuck is to remove the intake manifold .... and open the 'cover plate' directly underneath.
A4 valves can easily be 'unstuck' by simply spraying on "PB blaster" to the valve stems ... both through the spark plug hole ... the spray angled to the valve stem and on to the stems exposed by the removal of the cover plate. Spray the stems and 'work' the valve up and down by using an "L" shaped device through the spark plug bore.

If you do have stuck exhaust valves ..... continue your 'search' to find the pin hole water leak in your exhaust system (exhaust manifold and/or water lift muffler, etc.) that is 'back filling' the engine with WATER when you shut down. The A4 exhaust manifolds are notorious for pin hole water leaks.

kloudie1 · Jun 13, 2012

Good news that all the turning stuff is turning.. Get a headgasket and pull the head.. remove what I call the tappet gallery cover, the one Rich calls cover plate.. behind carb and intake manifold.. You can see the tops of the tappets .. There are adjustment screws /nuts on top.. don't mess with that yet.. Any valve that you see off its seat after you pull the head should get a squirt of oil on its stem so that the oil can drool down into the guides. Squirt the bottom of the guide inside the gallery so that some oil will wick up into the valve guide.. Take a block of softwood like pine and tap down the valves whose tappets you find loose .(take extreme care not to bend the valve). Roll the crank a couple of times and watch the valves.. re-oil the sticky ones tap down .. work em up down until they get free.. Continue to oil the stems top and bottom until the valves are completely free.. Clean out the tappet gallery and use engine oil to oil the tappet bores.. Make sure they are clean and free. .. Now check the valve clearance and set according to specification.. Spin it with the starter to make sure nothing is sticking before going back up with new head and gallery cover gaskets... Some folks might recommend Marvel Mystery oil in the fuel and in the crankcase until you've run it 4-5 more hours. Good Luck

RichH · Jun 18, 2012

Stuck valves on an A4 usually free-up easily .... just keep applying a rust penetrant to the stems and forcibly 'push' the valves down as you hand rotate the crankshaft. Once fairly free and the stems are repolished they will stay that way ..... but then carefully inspect the entire exhaust system for *pin hole* leaks between the exhaust gas side and the 'water side'.
Pressure test the exhaust manifold for pin holes.
If you have a jacketed 'connector pipe' between the exhaust manifold and the 'steam riser', ditto pressure check, etc. Ditto if you have the Pearson COPPER jacketed 'steam riser'. If you DO have the Pearson copper 'steam riser pipe' .... take it to a 'red metals' fabricator and VERIFY that the 'witches hat' inside is 'still there'. If the witches hat is missing water can be back-injected into the exhaust system (when the exhaust flow is minimal as when idling etc.).

Rick D · Jun 18, 2012

Suggestion

You have gotten plenty of advise. I was part owner of a 1914 Fay Bowen which had a re-power with a Grey Marine which I believe was the same block as yours. It was raw water cooled in salt water. It was way too much power for the hull.

Anyhow, we constantly battled carb and valve issues. The carb problem was stale gas since it didn't get used enough. The valves were because the engine never got hot enough nor ran long enough to burn off the residue. As a result, eventually the valves would get stuck in the guides. We had to do the PB blaster treatment several times over a week and work them, clean out the valve galley and change the oil a couple of times before all was back in order. (Another problem is that this engine had no thermostat.)

Anyhow, it looks like you are getting closer to identifying the problem. I guess you have ruled out a bad crank or cam. I assume you checked the distributor drive too. Good luck!

Edit to add: also, once we found that a valve spring was cracked. It had enough tension to close the valve when the engine was turned over by hand, but not when it was running. That was a bugger to figure out. We later found another. We replaced all the springs.

tommays · Jun 18, 2012

One of the things i found in owning two A4s is they changed the valve springs at point X in time and the new one ones are MUCH stronger

You should be able to find out by counting the coils and asking Moyer

The valves are pretty costly so there worth getting ground IF they seem in otherwise good shape

Due to being kind of cool i have found under the intake valves the motor built HUGE amounts of carbon to the point i was supprised the motor could even draw in enough air to run

The valve keepers can fall INSIDE the motor so IT is a good idea to stuff rags in the oil return holes to keep out parts and DIRT

The modern head gasket is THIN and you are supposed to use TWO to or the compression will get kind of high

Rick D · Jun 18, 2012

Thanks to TomMays...

...for these hints. I forgot about it (or at least was trying to):

"The valve keepers can fall INSIDE the motor so IT is a good idea to stuff rags in the oil return holes to keep out parts and DIRT

The modern head gasket is THIN and you are supposed to use TWO to or the compression will get kind of high "

RichH · Jun 18, 2012

tommays said:
The modern head gasket is THIN and you are supposed to use TWO to or the compression will get kind of high

VERY GOOD point .... at near the production series end of the Atomic 4, Universal 'unloaded' quite a few of the 'industrial version' (higher compression) A4s to Pearson. Don Moyer has an 'insert' that fits to the head and requires 4 head gaskets (two on each 'side' of the insert) to lower the compression ... you'll have to ask Don which serial number engines NEED this insert.

kloudie1 · Jun 18, 2012

Looks like a possible blown gasket between nearest and second nearest valve pockets in the head?? Cylinders 3/4 maybe.. Time to get some Clover valve grinding compound and a twirler stick and fix the seats. Rick's advice is excellent about packing the holes so the keepers can't get away from ya. Compress spring, pull the keepers and remove the valves .. rolling the engine to get the tappets loose as ya pull the keepers. Clean each valve being careful not to bend the stem or scratch the seating face or the stem. The example in this video is an ohv engine, but the technique is the same.. http://www.affordablegokarts.com/valve-lapping.php
Sounds like a consult with Moyer is in order re head gaskets/spacers/valve springs, as Rich says..
Oh.. ya gonna want to check the head for flatness and correct if necessary.. Also check the head mating surface on the block, especially between the valve pockets. .. Good luck

Rick D · Jun 19, 2012

Spring Compressor

You'll need a spring compressor; at least we did. Smaller is better. Look for a little one.

Rick D · Jun 19, 2012

Well, that ought to do it! Good luck and let us know how it goes!
BTW, It's really easy to lose the valve spring retainers when pulling them; good luck. I'm sure your valve spring compressor will be much better than the auto parts store ##@&&(+_ one we had.

Massive Coronary only Minutes from the Marina

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