Terrible sound when starting up!

[dsimon1044]

Hi everyone
I'm having a tough time getting my engine to start. When I turn the key, there is a terrible clanking sound that sounds like metal on metal. After a while, and usually, right before it kicks on, it reverts back the familiar smooth starting-up sound, then kicks on and runs just fine. Once the engine is warm, it starts very easily, but there is still a short initial clank, followed by a quick smooth starting sound, then fires right up.

Am I going to ruin the engine by running it? What could be causing that noise?

Additionally, and I'm not sure if the problem is related, but I've been getting water in my oil. (the telltale milky oil in the gearbox )

Does anyone have any experience with this? Any solution?

The engine was rebuilt less than 2 years ago and has less than 75 hours on it.

Thanks in advance!

Dave
Bristol '33

[captain kenny]

Starter

The milky oil is not good and you need to follow the procedure in the mmi manual to trouble shoot the problem. First you need to change the oil a couple times if the milky comes back it is not water from the exhaust. your clanky sound has to be the starter or flywheel pull the starter off if you have a bendix maybe all it needs is grease. I have a great guy that fixes all my starters and alternators look for a repair shop to help with the starter while the starter is off check the flywheel for slop or missing teeth.

[dsimon1044]

Thanks Captain Kenny. Quick question: if the problem is solved and the water is from the exhaust, how does this happen? Why did the water get in there in the first place?

Also, when you say "if you have a bendix maybe all it needs is grease" what do you mean? What is a bendix?

Thanks!

Dave

[sastanley]

over-cranking

Dave, water can intrude into the crankcase via the exhaust from 'over cranking' the starter and the engine not starting.

When the engine isn't running by itself, but is being turned over by the starter, the water pump is spinning...water is still flowing thru the engine due to the water pump and being injected into the water lift muffler..if the engine doesn't start, the muffler fills up and continues to back fill up the 'hot' exhaust pipe while turned over by the starter, and eventually dumps into the cylinders. If the engine starts normally, the pressure created by the exhaust pushes the water thru the exhaust system and overboard, which is 'normal' operation.

This "back-fill" apparently happened twice on my boat before I bought it..once resulting in some rust and apparently minor damage to cylinder #4. As a result, I am a few PSI low in that cylinder's compression # as compared to the others. My personal procedure is that if it doesn't start in 8-10 seconds, I close the raw water intake, then get her started, and then swiftly jump down and open the raw water thru-hull once it is running. The only real danger is burning up the impeller if you run it too long without water, but it doesn't seem to be a problem for a few (15-20?) seconds while you are trouble-shooting starting. In my opinion, the damage from water intrusion into the crankcase could be much more catastrophic! I've run other marine engines (not on purpose ) for minutes with the raw-water closed, and the worst damage has been replacing a burnt up impeller.

After a few oil changes to remove the water, if it comes back, it could mean a crack somewhere in the engine between the crankcase & a water jacket.

[roadnsky]

Also, when you say "if you have a bendix maybe all it needs is grease" what do you mean? What is a bendix?

Dave-
Shawn explained the water intruding from the exhaust, so I'll try the Bendix question...

Bendix drive units were used on early model A4 Prestolite starters.
Late model A4's should normally have a Delco starter with a solenoid that mechanically moves the drive gear in to mesh with the ring gear on the flywheel.

Do you know if your A4 is late or early model?

[dsimon1044]

I'm not sure if it's a late model or an early model. How would one find this information out?

Sorry, I know that's a stupid question, but this whole "fix your own engine" process is still new to me.

[roadnsky]

I'm not sure if it's a late model or an early model. How would one find this information out?

Sorry, I know that's a stupid question, but this whole "fix your own engine" process is still new to me.

From the FAQ section of this site:
Early or late model? How can I tell? What difference does it make? -
Most parts are interchangeable between early and late model engines. However, a few parts (particularly some of those used in fuel, ignition, and cooling systems) are unique to early or late models.

If you have an original engine from the mid-seventies or later, with an oil fill tube over the flywheel housing in front of the engine, you can be reasonably sure that your engine will require all late model parts.

If your engine does not have an oil fill tube over the flywheel housing, it may require a mix of late and early model parts. You will therefore need the following information before ordering:

1. To order ignition parts (including the "Ignitor"), you will need to know if your distributor was manufactured by Delco (used on late model engines), or by Prestolite (used on early model engines). Prestolite distributors are distinctively smaller in size, and their condensers are mounted on the outside of the distributor housing.

2. To order cooling system parts, you will need to know if your engine has a thermostat housing (a small dome-shaped casting) located on the front corner of the head, nearest the starter. This thermostat housing would indicate that your engine has a late model cooling system.

3. To order carburetor parts, you will need to know if your carburetor is made of aluminum or cast iron. Aluminum carburetors were used on late model engines. All carburetors were manufactured by Zenith or Bendix, so the manufacturer does not help in determining your carburetor vintage.

4. To order gaskets, you will need to know (1) and (2) above, plus the shape of your transmission cover. Late model engines used a square cover, and early model engines used a rectangular cover with a curved top ("tombstone-shaped").

[sastanley]

Dave, if you go to Moyer's home page, there is also a complete late model engine panoramic available...if you engine looks like that one, it is a late model..

http://www.moyermarine.com/360/index.html

But use Jerry's info above as well...if you are not the first owner, you never know what's been done!

[baileyem]

Dave,

Moyer Marine has put together and sells an Atomic 4 Owners Manual that you should seriously consider purchasing if you are going to work on your own engine. Calling Don directly with major problems is another way to go if you ever get really stuck on a problem.
Welcome to the A4 Brotherhood (sorry gals, I guess you're just one of the guys)

Mike

[dsimon1044]

Ok great, it's a late model engine. The oil fill tube is located above the flywheel house and the transmission case is a regular rectangle, not a rectangle with a rounded top.

Now that that's established, can we assume that it's a Delco starter? If so, any ideas on what might be causing the clanking sound, and any ideas on how I can fix it? Or does it require replacing the whole starter unit?

Also, Bailey, I have the Moyer Manual. You're right on - the thing is money. Fortunately, whatever I can't figure out from there can usually be found on here.

Thanks guys.
Dave

[sastanley]

Dave,

You should be able to remove the starter (two bolts) and check its operation on a bench. I am not real smart on starters, but my understanding is you give the solenoid juice (key or button to 'start') and it actuates the spinning drive gear which meshes into the flywheel teeth to turn the engine over...when you release the key or button, the gear retracts and hopefully the engine is running. If this gear is damaged or not actuating correctly, you might have a problem. More typical is the solenoid fails (bad/loose electrical connection sometimes), and all you hear is a click...but the gear doesn't actuate...this sounds the opposite of your problem.

That's about all I know. You may also benefit from removing it and taking it to a local shop for diagnosis...we have a fairly large Mennonite population around here in Southern Maryland and they are the go-to guys for starters/alternators and anything electrical. Alternately, you could send your starter to Moyer for exchange, but I'd do some testing before just sending it off.