Need Help with Atomic 4 in Chicago - Anyone?

[Smoothsailing]

Hello,

I have a rebuilt Atomic 4 in my sailboat and when I put it in this year it would turn over fine but wouldn't fire up. After putting ether in the carburetor it still wouldn't fire up so the mechanic's diagnosis was that there was no compression and I'd need a new engine.
Because of the value and year of the boat I'm reluctant to put another engine in it and wanted to see if anyone in the Chicago area knows any good mechanics that are familiar with the Atomic 4. The only mechanics I've dealt with are generalists and seem to know very little about the A-4 so thought an expert might have better news for me on what to do with the engine.

Thanks and hopefully someone out there can point me in the right direction.

[Baltimore Sailor]

If your mechanic "diagnosed" zero compression without running a compression test, get a new mechanic. But it appears you have already moved in that direction.

First thing: close your raw water through-hull valve before cranking the engine any more. It doesn't sound like you know much about the engine, and cranking her with this valve open will fill the cylinders with water, since the engine isn't running to provide exhaust pressure to drive the water through the exhaust system. We will hope you haven't filled them already -- but it's not that difficult to clean them out, it just takes a lot of oil changes.

NOTE: if you DID do a lot of cranking of the engine with the through-hull open, take all the spark plugs out of the engine and turn it over (after closing that through-hull) and check to see if water comes splashing out of the plug holes when you turn it over. If it does, you'll have to clear the cylinders and clear up the oil before continuing. That basically involves cranking the engine with the through-hull valve closed until water quits coming out of the cylinders, then changing the oil at least three times to get the water-oil mix out of there. The procedure for this is sticky'd somewhere here, I think. We'll get you there.

You don't really need an A4 "expert" -- these are simple engines using technology from the 1920s and '30s, and only need three things: fuel, spark and compression.

So the first thing to do is get to an auto parts store -- Advance Auto Parts or whatever's common in your area -- and pick up a basic compression tester. Take it to the boat and follow the directions to get a first approximation of your compression. It'll be lower than normal because you'll be testing on a cold engine, but you should get at least 80 lbs in each cylinder. If you get that, step one is good. If you don't -- well, we can check the other things too, just to see how bad a condition the engine is actually in.

After you've made sure there's no water in the cylinders -- or cleared it out if there was -- and run the compression test, you can check to see if fuel is getting to the plugs by putting them back in, cranking the engine a bit (keep that through-hull valve closed), and then removing the plugs to see if they are wet with gas.

Test for spark by cranking the engine over and holding a plug wire close to a head nut and see if you get a good spark jumping to it. Others might have better suggestions to more fully test the primary ignition circuit, but I've always done it this way. I usually put a small nail or something similar up in the plug wire to get a good conductor sticking out of the socket, so that I can really see the spark jump.

That's about it for the start. If you can find which of the three things your A4 needs that is missing, you'll be on the road to recovery without spending big bucks on a new engine.

Good luck!

[tenders]

My diagnosis is that if you have a mechanic whose answer to "no compression" is "new engine," then you need a new mechanic.

No compression suggests a blown head gasket or sticking valves, which are eminently repairable by a layperson. I see Baltimore has offered details on how to refine the mechanic's alleged diagnosis, which will help get things started.

[Dave Neptune]

Oh boy

See Baltimore and Tenders. My engine had no compression so the PO let it sit until it siezed due to water incursion. He was told the A-4 needed replacing and sold it to me as is. I am a mechanic of sorts by trade so I replaced 1 exhaust valve, ground the valves, kissed the seats and KNOCKED the pistons loose. My lil beastie (the A-4) has now been running for me for 26 years and other than the valve and headgasket is still original and the engine was commissioned in late 1969.
Bribe a friend or neighbor for assistance if need be but at the very least get a real mechanic that will discuss remedies not hi-dollar replacements.

Dave Neptune

[sastanley]

Smooth, welcome to the crowd. You may end up being your own mechanic on this engine...that is what happened to me.

These motors do not need ether to run. Someone coined the term "motor crack" & I have 'borrowed' that term frequently.

The engine will require FULL CHOKE to start. You can see the choke butterfly if you remove the flame arrestor. Try to get visual confirmation that the choke closes 100% when you actuate the cable. If you are only getting partial choke you can spin the motor forever and it may never start. Once it is running, you can usually open the choke after just a few seconds.

+1 what everyone said about the water intake..you can open it up once the engine is running successfully. It really should start after 2 or 3 seconds of cranking once you get all the details ironed out...fuel, spark, compression.

[Smoothsailing]

Thanks for the help guys!!!

I'm really glad I found my way to this forum...thanks for taking the time to give your advice and help on this guys...it's very much appreciated and I now have a wave of new hope on getting this running without breaking the bank.

I will be first taking the advice and getting a new mechanic and next getting all of this info over to him...thanks again and I'll report back.

[tenders]

Do you have details on the rebuild? I'm not understanding why a newly-installed rebuilt engine doesn't roar to life and/or have somebody standing behind it to get it roaring.

To be honest with you I'd be willing to guess that in the time you'd spend finding and tracking down a mechanic, you'll be able to find and fix the problem.

[ILikeRust]

I agree with the suggestion to get a new mechanic. If you squirt ether in and the engine doesn't kick over, that doesn't mean you have no compression. It very well could mean you have no spark.

And even if you truly do have no compression, as others have stated, that doesn't mean you need a new engine.

Amazing how mentally lazy some so-called mechanics are - they're pretty free with spending your money on a new engine.

The Atomic 4 is a little bulldog of an engine. Barring some catastrophic failure, such as a cracked block or broken connecting rod, there's no reason it shouldn't be able to run with a little fiddling and tweaking.

[CalebD]

Save money and time.

To be honest with you I'd be willing to guess that in the time you'd spend finding and tracking down a mechanic, you'll be able to find and fix the problem.

If you don't already own a socket wrench set get one for Imperial sizes (not metric). Get the MMI A4 manual and use this forum to help you diagnose your issues. Save yourself a lot of money (@ $80/hour for a mechanic).

When I first got our boat w/A4 I tried to find a mechanic around the NYC area for an overheating issue. I spoke to Don Moyer by phone and he helped me diagnose the issue we had - needed new cooling water pump. That was seven years ago and I've been doing all the work on our A4 myself ever since. The gang here has been more then helpful too.

I will say this though, since your engine did not kick over after using ether to start it - it sounds like either (A) you don't have any spark (ignition/spark plug issue) or (B) your compression is too low. I would expect at least some combustion from the ether if there was compression in one of the 4 cylinders.

The simple compression test is to remove each spark plug in sequence, cover the hole with your thumb and turn the engine over. If it pushes your thumb up enough to let gases out there is compression. If you can hold your thumb over the hole without being pushed off or up then compression is your issue. A gauge is nice to have but not absolutely necessary if you are just trying to determine if your engine has compression. If you need to know how many PSI you have you need a gauge.

[Baltimore Sailor]

I don't like the thumb test because I have small hands, and I'm never sure that I've got the hole covered enough to prevent blow-by. (I couldn't play an open-holed flute or clarinet for the same reason.) You fat-fingered guys have an advantage here. I've often thought about putting something together from a science lab cork with a glass tube through it and a balloon attached on the other end, so that you could just jam the cork down in there and watch the balloon inflate and deflate to get a ballpark idea of how much compression there is.

A compression tester only costs about $20-$30 at Advance Auto Parts, and I like having real measurements for my engine, not just ballpark ideas. It's also needed to tell the difference between cold compression and warmed-up compression, and the difference adding a bit of Marvel Mystery Oil makes.

I also suggest a set of box/open-end wrenches along with the sockets. Sometimes you just can't get a socket on something you can get a regular wench on. This season I splurged on a set of Craftsman ratcheting box wrenches -- sometimes it's a drag to have to reset the wrench when you're reaching way back in there. But those can wait for now. Regular box wrenches will do just fine.

I don't know about the rest of the commentariat here, but I'm looking forward to hearing a report back on this engine. I just have a feeling that it's going to be something crazy simple that's keeping it from running, while his "mechanic" wanted to put in a new engine. (Fingers crossed!)

[jacques debauche]

Wrenches

The wrenches needed for the A4 are properly called "SAE" (for Society of Automotive Engineers) not "Imperial" (except maybe in the UK). Asking for a set of "Imperial" wrenches might get you a set of Whitworth wrenches (or should I say "spanners"), yet another size system. A friend of mine had a 1960's Volvo which required metric wrenches for the Swedish-built bodywork, Whitworth wrenches for the British-built engine, and SAE wrenches for some odd domestic bits which had been added to keep the car running. Needless to say, the correct wrench was never at hand.

Good luck with the A4: it is really a simple and forgiving beast. The fact that it turns when cranked means that you are 95% of the way toward getting it running.

[Smoothsailing]

Thanks for the help....it was just a simple fix!!!

So you guys were dead on...I had another mechanic look at it and I just needed some new spark plugs...I also had a cracked distributor cap and need a new rotor but was able to pick those up for cheap and I'm all set...fired her up yesterday and she ran just fine.

Funny enough I crossed paths at the marina with the mechanic that diagnosed no compression after just listening to it for 2 seconds and told him it was just the spark plugs and he was still convinced it was a compression issue...told him we did a compression check and it was fine and he just stood there looking like an idiot.

Really glad I reached out to you guys and I'm glad to be on here. I'm going to also take your advice and pick up the Atomic 4 manual and brush up and hopefully I'll be able to give some personal feedback to help someone else down the road...haha.

Thanks again guys....have a great summer!

[blind navigator]

A4 help in Chicago

Glad you got it running, Smoothsailing. If you run into serious A4 problems again in the Chicago area, give Crowley's Yacht Yard a try-they do know their A4s. Several years ago I had the dreaded water in the crankcase oil, thought I had blown the head gasket but the compression was ok. I had called Don and priced out a rebuilt A4, but it turned out to be only that the pipe inside the water jacket in the exhaust had rotted out-it took them three tries to get it right
(pressure tests after welding were good but it started to leak again after it got hot) but they kept at it and will only return it to you when it's done right. For what they had to do, the charges were quite reasonable. This is three years later and the original 1974 A4 is still running strong. Their rigging shop does good work as well.