AQ 131 A275 Cylinder Head exhaust port

"Chris, first thing I would do

"Chris, first thing I would do is to make sure that the throttle cable is secured to the block,and observe what is happening at the carb linkage when you try to give throttle (is it moving, or...?). If all OK, then I would remove the crankshaft pulley and verify that the three marks on the timing gears are where they should be. If the marks are where they should be, then I would check that the ignition timing is 6º BTDC at idle and 32-36º at 4,200 RPM. If OK, then I would have a look at the carb accelerator pump."

"Thanks EP,

I'll have t

"Thanks EP,

I'll have to wait until Thursday to work on it some more. I have to work on Tuesday and Wednesday.

Best as I can tell, the throttle cable is secure and operational. The cable is connected to to a piece of metal that presumably opens the butterfly in the carb. It moves like it should. I don't have any idea what the carb accelerator pump is, but "Mr. Clymer" can probably show me. I'll pull the crank pulley on Thursday and verify position. I just don't understand why it would run smooth throughout the entire RPM range, but not when it's turning the prop. Doesn't make any sense. Oh well, Thanks again EP.

Chris"

"EP,

Those six pulley screw

"EP,

Those six pulley screws that need to be removed to take the pulley off? I don't have 6 screws, just a bolt and washer. It's also got grooves for three v-belts. That's why I didn't pull it off the other day.

Chris"

"So, I just tried to remove th

"So, I just tried to remove the pulley from the crank and the bolt won't budge. It laughs at the air tools. I'm going to have to find another way to set the crank to the proper position. Suggestion, anyone?

Thanks,

Chris"

"Well, I set it the only way I

"Well, I set it the only way I know how; that is to pull the #1 spark plug and stick a rod down in there and turn the crank until #1 piston no longer moves upward and both valves are closed indicating the end of the compression stroke. Lets hope that works. I don't know how else to do it without being able to get the crank pulley off.

Chris"

"I managed to get the crank pu

"I managed to get the crank pulley off. It's no wonder I couldn't see the timing mark, it rusted away long ago... Anyhow, I put a new one on there, set the three marks, installed the belt, I made sure that I had the wires in the proper firing order (1-3-4-2), proper gap in the plugs, the rotor is lined up with the #1 notch and she won't crank, she won't even turn over. I'm beginning to wonder if I have a bad battery. I took it to Autozone and they tested it and said it was okay, but it seems like it's discharged. It's as if it didn't have enough oomph! to turn the engine. It'll turn the crank 1-2 revolutions, maybe 3 on occasion, and then give up.

On a hunch, I pulled the #1 plug and made sure that it had spark because I put a PerTronix 3 Ohm coil in there yesterday. It has spark.

The battery was purchased last year. I wonder if I should go buy another one, just to rule out the as a cause of the problem.

It's got fuel, it's got spark, it's got spark when it supposed to have spark, what am I missing?

Oh well, I'll keep at it,

Chris"

"First, make sure there is no

"First, make sure there is no water in the cylinders so that you are not hydrolocking the engine. If OK, my guesses are a poor ground between engine block and negative of battery, or neutral safety switch incorrectly adjusted or toasted, or the starting relay is NG."

"The starter solenoid will act

"The starter solenoid will activate, the just isn't enough juice going to the starter motor. I cleaned the all the battery cable connections with the exception of the hot connection at the solenoid. I'm beginning to get a little gun shy of taking things apart to clean them. Seems that they tend to break in the process. Just had to replace a cracked distributor cap. There's another $60 dollars gone.

I guess before it's actually in the water under "worry free" conditions, I'll have replaced the top half of the engine and everything attached to it. Not exactly what I had planned.

In reference to hydrolocking, how, pray tell, would water get into the cylinders?

Thanks,

Chris"

FYI - I just pulled all the pl

FYI - I just pulled all the plugs. They were soaked in gasoline. Not sure if that's good or bad.

"As far as I can tell, there i

"As far as I can tell, there is no water in the cylinders. The engine turns with ease without the plugs.

Is it possible to have too much compression? Or am I getting warm on the theory that the battery doesn't have enough juice to turn the flywheel and overcome the compression/resistance at the same time?"

"Gasoline is, in this case, be

"Gasoline is, in this case, better than water.

Let's see. You have gasoline, you have compression, you have verified timing marks in timing gears, you have spark, and the engine does not start. That does not leave too many possibilities, and ignition timing is a strong suspect. Amongst other things, you could have the distributor 180º off. Try to put #1 cylinder (the one closest to the heat exchanger) at the end of the compression stroke, then remove the distributor cap and see where the rotor is pointing: it should point towards the lead going to #1 cylinder. If it does not, then you will have to set the distributor correctly.

When it comes to the battery, you can borrow any 12V battery and parallel it to your current battery with a set of battery booster cables."

"Correct me if I'm wrong.

"Correct me if I'm wrong. The end of the compression stroke is when both valve are closed and the piston is at the end of the upward stroke (TDC)?

Also, I've tried previously to jump start the boat off the truck. No joy. Still doesn't want to turn very well.

Chris"

"You are correct regarding the

"You are correct regarding the end of the compression stroke. And, as you probably know, the distributor turns clockwise.

You may want to run one fo the booster cables from the block to the neg of the battery and see if it makes any difference. If nothing changes, you may have to start thinking on a bad starter or bad starter solenoid."

"Well, well, well...

It was

"Well, well, well...

It was the starter. I put a new one on and she turned over without any problem. The timing is set, however I'll take the timing light out on the water with me. Hopefully, this will be the end of the mechanical stuff. I fixed all the electrical last weekend. Now it's time to work on the cosmetics.

I'll let you know how "Sea Trials, Part II" goes tomorrow.

Chris"

"Sea Trials, Part II:

A com

"Sea Trials, Part II:

A complete success. Timing was just a hair off initially, she backfired twice after getting underway. A quick adjustment seems to have corrected that. Top speed for the day with the 14x19 prop was 34 mph at 4500 RPMs based on GPS. Pulled the kids around on a ski bob at 25 MPH at 3500 RPMs. The electronic ignition works as expected, flawlessly. And most important, to me anyway, I know the AQ131A engine inside and out. Now I need to study prop dynamics - what to use and when to use it. Top end speed, towing ability, etc...

Anyhow, thanks for everyone's help, especially EP.

Chris"