Hot cylinders...

[sailhog]

Howdy folks:
I got the new head gasket on.... She started right up and there's no evidence of water in the cylinders.

I've had her running for a total of about 20 minutes, and I'm still troubleshooting an intermittent shutdown problem, although I think I have that winnowed down to low fuel pressure. I've bypassed the OPSS, the primary circuit, the priming bulb, the Racor. The carb is clean as a whistle, floats adjusted. All that's left is the Facet electric pump, which, according to Don, is a likely suspect, as it's old and the Catalina 30s are susceptible to low fuel pressure, etc....

Here's my new problem. I'll give it to you in stages:
1.) I did a spring replacement, as three of the springs were broken. In the process I MAY have let one of the valve keepers fall into the crankcase via the little holes. I don't know that this happened, as I had the holes plugged most of the time, but I still can't account for one of the keepers. I had ordered an extra set, at the prompting of Ken at MMI (nice call, Ken).

2.) The engine ran incredibly well for those first 20 minutes -- more smoothly than I've ever heard her run. She started right up after a couple seconds of full choke. All was good. Today, however, I had difficulty getting her started. She finally did start, but she was running roughly, then suddenly she seemed to snap out of it. However, just as she snapped out of it, I touched the #2 spark plug and it was so freaking hot that it gave me a blister. So I shut her down. The #1 spark plug was just as hot... but #3 and #4 were a normal temp -- just warm. The engine was only running for 60-90 seconds. During that time I fine tuned the timing by rotating the distributor. The #1 and #2 sparks were badly fouled, while #3 and #4 were more or less normal. Also, the water was exiting the exhaust at a normal rate.

3.) While she was running well, I noticed that there was an oil leak coming from the oil pressure adjustment nut. I tightened it down, thinking that might stop the leak. It didn't, so I tightened some more to no avail. I have a sealed washer on the way.... Also, my oil pressure and water temp gauges are in-op. Both are on the way. Also, the engine was rebuilt by MMI back in 2002.

4.) I recently opened up the water jacket and cleaned it thoroughly, along with the T-fitting, replaced the gasket and installed new bolts. I don't think this has anything to do with the problem, but I thought it should be mentioned.

So there it is. What could cause the #1 and #2 spark plugs to heat up like that, and yet allow #3 and #4 to remain relatively cool? Could it have anything to do with the missing valve keeper? Again, I don't know that it's in the crank case.... I know this is scarce and incomplete information to go on, but it's the best I can do at the moment.

Thanks in advance, gentlemen.... Sorry to keep coming back to the well....
d

[Mo]

Hi Sailhog,

My thinking.

Ensure all cylinders have fire...pull the plug and then put the wire back on. Hold close to head and ensure you see a good spark.

Next sort out the fuel delivery problem and start it. Maybe the others are cooler because they might be getting less fuel.

[sailhog]

Thanks, Maurice. Should the spark plugs ever get so hot that you can't touch them? Does it indicate a problem? Before finally starting her this evening, I cleaned the plugs with a brass wire brush and a some wet/dry sand paper.

[Mo]

Fuel starvation???

Plugs can get hot. I really think the cool ones were either not firing or starved for fuel and didn't get enough to heat up.

First lets talk plugs for a second. One of the main things to ensure is that you don't have plugs that "run too hot". This has to do with the plug itself...not the engine running hotter or colder.

If the plug is a hot running plug it is self cleaning ...fires at a higher temp (too hot can burn a hole in piston). If plugs are too cold you find they need cleaning from carbon build-up... they are not firing at a temp high enough to burn all the combustible material.

That's the quick low down on that stuff. For our purposes this means we do not want to have plugs that will burn the fuel too hot or too cold. If we use the recommended plugs suggested my MMI all is good on that one. There is a range and I always use the hotter running ones.

Next, ensure all plugs are:
- correct spec for our engine
- the same type in all four cylinders
- correct gap
- snugged tight.
- good spark to each plug.
- each plug emits a good spark.

Now we move on. Was the head hot to touch or was it warm to touch. That would be a pretty good indicator of something wrong on the top end cooling.

With all that said, if you have good spark at the plug it must be a fuel delivery problem. I would think you could have cylinders cooler because there is less combustion going on in them...those cylinders were starved for fuel.

some possibilities:
-clamp loose on line somewhere (or gasket on a filter setup) and sucking air.
-fuel filters plugging up and pump working hard to draw fuel through them.
-dirt got into carb and then passed...could be why she started to run better.
-as you were thinking, fuel pump could be on the way out.

Well Mr. Sailhog, that's what's going through my tiny little mind at this time. But I think those cylinders were cool due to fuel starvation.

[sailhog]

Mo,
Thanks for the thoughtful response. I've gotta get more systematic in my thinking. All my adult life I've kind of thought of myself as being smarter than the average bear. Not a lot smarter, but maybe a little smarter. I do okay in daily life. With these A-4 engine problems, however.... it's like I'm feeling this early onset of Alzheimer's coming on or something. Can't really describe it, but I feel sort of stupid, like all of this is just beyond my grasp. Then again, a couple of months ago, I didn't know what a compression test was. Sometimes I feel like I've figured some things out, sometimes I feel like someone scooped out my brains while I was sleeping and filled my skull with dinosaur ---t. If I find out somebody actually did this to me, I will hunt them down and.... tell them that they did a bad thing.

My sparks are the Champion RJ-12C -- the spec plugs that MMI sells. They are gapped at .035, all are the same, all snugged down tight. The head felt much warmer on the forward end and cooler on the aft end. But I wouldn't say it was "hot" on the forward end. You could hold your hand to it. The spark plugs, however, were a different matter.

When I changed the head gasket, I had the head sandblasted and had to drill out the water port holes -- five in all. I stuck a wire clothes hanger in there as well. An unbelievable amount of material came out of that thing. Anyway, there's a lot more water running through the head now than there was, and water was exiting the transom at a good rate when I had the engine running. It just freaked me out that the sparks were so dang hot. The fact that it wouldn't start so easily, along with the mystery of the lost valve stem keeper got me thinking that some of these things are connected.

Thanks again....
d

[Mo]

Anybody else with ideas jump right in. d, I'll give you some time to check some things.

#2 of you initial post sure sounds like air to me. The next day a hard start then got better. Might be a loose clamp or needs a clamp somewhere.

D, I won't be on here in the morning tomorrow as I'm going to try and launch my boat...good luck with it and don't despair.

Spark, fuel, air...it's got to work...it just don't know it yet!

[ndutton]

Dwight,

In the absence of a working temp gauge, do you have a non-contact infrared thermometer? It would provide some critical data numbers for the plug temps. I'll get to my boat today to run her up and measure some temps for comparison or maybe others already have that info.

On another front, I agree with replacing the fuel pump, working or not. It doesn't cost that much and eliminates it as a possible problem. As part of your shutdown diagnosis, have you opened the carb bowl immediately after shutdown to see if there's any fuel in there?

[sailhog]

Neil,
Thanks for the response. Please don't make a special trip out to your boat. I certainly appreciate it, however. I'll try to locate an infra-red temp gauge. A bit of good news... I've located the missing valve keeper, so all are accounted for.

It hasn't occurred to me to check the carb bowl after a shut down, but will do so.

Regarding the fuel system: I've bypassed the OPSS, the primary circuit, the priming bulb and Racor. Each bypass produced the same result. It would run great for approximately 30 seconds, then abruptly shut down.

However, whenever I kept priming the bulb, essentially using it to move fuel, the engine ran fine. When I quit priming the bulb, it ran for 30 seconds, then quit. I can feel the presence of air in the bulb. After pumping it a few times, it hardens up. The hoses are new, all the hose clamps are tight. I removed the anti-syphon valve, as I understand they are candidates for air leaks.

That's the skinny this morning. Thanks again for all your help.
dw

[ndutton]

Regarding the fuel system: I've bypassed the OPSS, the primary circuit, the priming bulb and Racor. Each bypass produced the same result. It would run great for approximately 30 seconds, then abruptly shut down.

If none of those things affected the symptom then none of them are the immediate problem. I believe I read you've had it running for much longer than 30 seconds, like an hour before shutdown. Were you pumping the squeezy the whole time?

Cheap infrared thermometers can be found at Harbor Freight Tools, something like 30 bucks. And no problem going to the boat, it's just the excuse I was looking for.

[sailhog]

I was pumping it every 15 seconds or so when I had it running for longer periods of time.

Neil, my engine problems could be an all-too convenient excuse for you to drop by your boat.... because I'm ALWAYS having engine problems.... This could work out well for both of us!
d

[ndutton]

You clearly have had multiple issues and I'm sure some of them have made others all the more confusing. For example, I recall your starting problems with a frozen choke but even after resolving that you still had broken valve springs, water in the cylinders and what appears to be a fuel delivery problem. It could be easily assumed that the choke replacement didn't solve THE problem but it actually was a step in the right direction. Now the choke is behind us and so are the water incursion and valve train problems.

If you continue on the current path of chasing down every symptom completely you'll end up with a smooth running and reliable engine, I'm sure of it. Compare where you are today to two months ago. With manipulation you can get the engine to run smoothly for an hour.

And I need to frequently go to the boat if for no other reason than to check the operation of the fridge and the only way to do a thorough check is to sample the beer - and once opened it can't be resealed, and so on.

[sailhog]

That post pretty much sums up this ordeal. But as you said, progress is being made. I think I'll have done everything you can do to an A4 while it's still in the boat.

Enjoy that beer. And thanks....
dw

[ndutton]

Dwight,

Ran the engine for 30 minutes at approximately 1000 RPM, fast enough for the alternator to charge. Switched the battery banks to charge a partially depleted bank thereby applying a modest load to the engine.

• Control panel temp gauge - 110 degrees
• #1 spark plug - 162 degrees
• #2 spark plug - 168 degrees
• #3 spark plug - 175 degrees
• #4 spark plug - 178 degrees
• Fridge working [buuurrrppp] good

Comparing these numbers to your estimates supports Mo's no fire suggestion pretty strongly I think. Looks like you might have yet another symptom to chase down. Plugs, wires, dist cap, rotor.

Do you have electronic ignition or points?

[sailhog]

Neil!
Thanks much, amigo! I have points, and I'm wondering if I have poor wire connections from dist. to the spark. I'll be back at it this weekend.

Hope your refrigeration is keeping that beer cold. Once I get my engine running and refrigeration installed, we can have a virtual chug-a-lug contest.

I'm feeling a wave of relief having located the missing valve keeper.... Can't wait to this project is behind me.

Thanks again....
dw

[ndutton]

It may seem like I enjoy spending other people's money but I recommend replacing the plugs, wires, distributor cap, rotor, coil, upgrading to electronic ignition and be done with it.

Although you've been a little deeper into it than I have, the only difference between our journeys is that my engine ran pretty well during the aggressive replacement process.

I practice what I preach. I replaced the choke, throttle and shift cables, rebuilt the carb, replaced the electric fuel pump, replaced all the fuel hoses, replaced the plugs, wires, cap, rotor, coil, upgraded to electronic ignition, replaced the alternator, engine wiring complete, battery cables, ignition switch, raw water thru-hull, exhaust hot section, waterlift muffler and on and on. All the items were working fine before replacement, no performance problems whatsoever. This was a strategy due to the unknown age of the components and making my boat my own. I saw no advantage to waiting for parts to fail before replacement.