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Grizzle86

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My engine is a 1989, 3.7L Alpha One, 4-cylinder, 224 CID, 165 HP. Recently, maybe a month ago now, it went from running relatively normally, (at least in the front yard, with muffs) to not running at all, i.e., starter motor cranking normally, but not even attempting to fire.

The first thing that I looked at was the carburetor. Whether right or wrong to start there, I don't know. But, I saw fuel being added as the throttle was raised. So I thought, well, I don't know crap about carbs... so I decided to start troubleshooting the ignition system because that seemed like the most logical place to begin.

While I was turning it over excessively (with water running) in a moment of impulsiveness, thinking that maybe I had just flooded the engine with fuel while #&$!ing with the carb, I noticed the ignition coil was incredibly hot as I burned the &%$# out of my leg on it.

I checked under the distributor cap and noticed that the rotor contact was cocked 90 degrees to the left and completely busted: plastic was broken and missing, etc. So, decided to just replace cap and rotor (20 bucks total, cap may have not been necessary, but did it anyway because I like to waste money). At this time, I also replaced spark plugs due to the fact that they were very fouled and, once again, probably just wasted money.

At this time, nothing has changed, and the symptoms are the same as before I replaced the rotor. I am not quite sure what to try next, troubleshooting wise. I am also willing to entertain the idea that I don't know #### about boat motors and maybe I should be looking somewhere totally different to find the source of this problem. Whatever the case may be, I definitely can't afford to drop this off at the local shop and leave my bank account at the mercy of the mechanics. Thanks in advance to anyone interested in helping me out.
 
I had this happen to me on an over powered street machine I once had. The factory (prestolite) had forgotten to put the wick "oiler" for the distributor shaft and it wore excessively, eventually wobbling to the point where the rotor hit one of the points on the cap. Damage to my rotor very much like yours except I also sheared the pin that attached the distributor shaft to the gear on the end of it.

As a first test... REmove cap and see what shape the new rotor is in. Check for side to side wobble in the rotor shaft.
Second...
REmove the spark plug from cylinder #1 and hold your finger over the plug hole. Crank the engine in short taps until you feel pressure on your finger. You will likely need several attempts to get this right but youwant to stop the piston at top dead center on the compression stroke (hence the pressure on your finger). When you get to that point, the rotor on the distributor should be lined up with the contact in the cap for the wire running to the spark plug for #1


VEry likely by this point you will have found something "not right"
 
Last edited:
sandkicker said:
As a first test... REmove cap and see what shape the new rotor is in. Check for side to side wobble in the rotor shaft.
Click to expand...

The new rotor seems to be undamaged. When you say side to side wobble... should there be any give at all? I can move it a small amount, maybe 20 degrees or so.
 
The 3.7 or imfamous 470 used point igniton.

Before we go any further confirm or denie this!!!!

We cant help without knowing the facts.

If it is points you probably fried the points.

Need more info please

Wobble = side to side movement.

The distributor is installed on an angle, thus the housing bushing wear out, thus the shaft wobbles side to side when it gets warm thus a loss of point gap or any gap for the ignition........
 
kghost said:
The 3.7 or imfamous 470 used point igniton.

Before we go any further confirm or denie this!!!!

We cant help without knowing the facts.

If it is points you probably fried the points.

Need more info please

Wobble = side to side movement.

The distributor is installed on an angle, thus the housing bushing wear out, thus the shaft wobbles side to side when it gets warm thus a loss of point gap or any gap for the ignition........
Click to expand...

Update, my distributor definitely does not have points. After checking for play in the rotor, there seems to be no unnecessary play in the distributor shaft. I can twist the rotor, but snaps back to its original position like it should.
 
sandkicker said:
I had this happen to me on an over powered street machine I once had. The factory (prestolite) had forgotten to put the wick "oiler" for the distributor shaft and it wore excessively, eventually wobbling to the point where the rotor hit one of the points on the cap. Damage to my rotor very much like yours except I also sheared the pin that attached the distributor shaft to the gear on the end of it.

As a first test... REmove cap and see what shape the new rotor is in. Check for side to side wobble in the rotor shaft.
Second...
REmove the spark plug from cylinder #1 and hold your finger over the plug hole. Crank the engine in short taps until you feel pressure on your finger. You will likely need several attempts to get this right but youwant to stop the piston at top dead center on the compression stroke (hence the pressure on your finger). When you get to that point, the rotor on the distributor should be lined up with the contact in the cap for the wire running to the spark plug for #1


VEry likely by this point you will have found something "not right"
Click to expand...

Tried your method without much luck. Instead I used a wooden dowel to measure when the piston was TDC. Is there a way to know if it is the compression stroke or the exhaust stroke? Seems to be pointing directly at the correct spark plug wire when it's supposed to.
 
Grizzle86 said:
Tried your method without much luck. Instead I used a wooden dowel to measure when the piston was TDC. Is there a way to know if it is the compression stroke or the exhaust stroke? Seems to be pointing directly at the correct spark plug wire when it's supposed to.
Click to expand...

Stick a rubber hose in the spark plug hole, and then feel for compression (it's easier), then blow into the hose to confirm if you want. If the rotor doesn't line up with #1 on the compression stroke, you must take out your Dizzy, and turn the rotor till it does, then drop it back in.
 
start with the basics,

1. compression
2. spark...........remove the spark plugs, if you have one use a spark checker and check for spark on each wire. if no checker use a spark plug connected to the wire and holding it with some insulated pliers make contact with the electrode to engine ground, or get a jumper and connect to the threads of the spark plug and the other end of jumper to engine ground. crank engine over and confirm if there is spark for each wire, should be blueish in color if yellow or orange there may be a coil/voltage or module (pertronix in distributor) issue..

3. fuel.

you must have all three in order to run, find out which is missing and then we can continue...
 
MikDee said:
Stick a rubber hose in the spark plug hole, and then feel for compression (it's easier), then blow into the hose to confirm if you want. If the rotor doesn't line up with #1 on the compression stroke, you must take out your Dizzy, and turn the rotor till it does, then drop it back in.
Click to expand...

Took your advice and used a compression gauge hose and a dowel to determine top dead center of cylinder #1, successfully found the TDC position with the aid of an arrow shaft. Once the compression stroke started, I used manually cranked the fly wheel so I wouldn't pass TDC. Marked the position of the rotor, adjusted the distributor housing accordingly, still nothing. Bought a spark tester, I am getting no spark at any of the 4 spark plugs, and also no spark at the ignition coil to distributor high tension lead. I am getting 8 volts at the ignition coil from the battery. I noticed none of my gauges were working when I turned the ignition switch to "On" so I checked and the 20 amp fuse at the ignition switch was burned out. Replaced that, gauges working now, but still not sparking at the high tension lead connection on the distributor. I am leaning toward a bad ignition coil, however the resistance readings I am getting off of mine seem to be "normal." However, my basis for normal is from about 5 conflicting internet searches, since the merc manual doesn't give me the readings I should be getting. The primary coil is reading about 1 Ohm, and the second is reading about 10K ohms.
 
If your coill is the original then they are cheap to replace, If it is original it is a external resistor coil.

You could TEMPORARLY connect a switch wire (on/off switch connected inline) from the battery to the + of the coil, DIsconnect all other wires going to the + and tape off so no shorting occurrs. Turn the switch on before cranking and see if this gives you spark. If not disconnect the TACH (grey) wire from the neg - coil and retest. If tach is bad it will take the ignition out. Look at the shift interuptor switch (shift cable plate where two cable attach) make sure the switch is not activated. This switch shorts the ignition to ground when shifting out of gear. If it is bad it will short the ignition out.
if you have a meter the micro rollered switch is simply a on/off switch. So it should be OPEN when not activated (no continuity)

If I am not mistaken and it has been a while so I may be wrong here but, If you take the - leads off the coil, connect a wire to the - coil and run a switched wire (in line on/off switch) and connect the other end to ground, with power to the + of the coil and switching the neg - of the coil to ground this should cause the coil to fire and you should be able to see this with the spark checker connected to the high tension lead.

If this works this will say the coil is good.

It is very possible that the pertronis pick up went bad.

If you have access to the original points parts the were removed, point plate, points, condensor you could swap back and see if that works.
If it does it confirms bad pertronix.

Other wise I am not sure what you can do to trouble shoot any further without spare/replacement parts........
 
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