Broken wire on rectifier.

CHEF06

Cadet
Joined
Oct 1, 2006
Messages
25
Ok I was having some problems getting my erude 81 115 to get up on plane. I had a mechanic look at it and he told me that it was only firing on two cylinders. He said the reason was either the stator or power packs. I got it home and started looking at things alot closer. I found that the red wire that comes off of the rectifier/regulator was broke. My question is would this make my two cylinders not fire? Obviously I will have to replace the rectifier, but do you think I will have to replace the power packs or stator? Thanks Mike
 

HighTrim

Supreme Mariner
Joined
Jun 21, 2007
Messages
10,486
Re: Broken wire on rectifier.

I dont really understand his reasoning for saying the stator. B4 you go out buying parts do a few tests first, do you have an ohmmeter?? Start out with a basic compression and spark test which ill post below and these checks for the rest.

Checking Rectifier Diodes

Place meter in Hi ohms position

1. Disconnect rectifier lead from terminal block. Connect one ohmmeter lead to either yellow or yellow grey rectifier lead, and other meter lead to ground. Note reading

2. Reverse leads, and note reading. Infinite or very high reading in both checks indicates diode open. zero reading in both checks indicates diode is shorted. Normal diode will show a reading in one direction and no reading in other.

3. Repeat with other rectifier yellow lead.

4. Repeat test, connect meter between rectifier yellow lead and rect red/purple lead. Between yellow/gray stripe rectifier lead and rect red/purple lead.

If you want checks for stator and power pack let me know. Here is a compression and spark test, do this first.

(Compression & Spark Test)
(J. Reeves)

1st - Regardless of what problem one might encounter, always start with the basic troubleshooting procedure. Check the compression which should be in the range of 100+ psi (somewhat less on the smaller hp engines) and even on all cylinders.

2nd - With the spark plugs removed, rig up some type of spark tester whereas you can set a gap to be jumped. On magneto ignition systems.... and also the Battery Capacitance Ignition system OMC engines from 1968 to 1972, set the gap to 1/4". On the solid state OMC ignition systems from 1973 to the present, set the gap to 7/16". The spark should jump the gap with a strong blue lightning like flame..... a real strong blue snap!

If there was no spark, on engines from 1973 up, disconnect the RED main electrical plug at the engine. Remove the s/plugs. crank the engine via the starter solenoid (jumper bat term to small 3/8" term nut, not the ground nut) and observe spark. If spark is now okay as stated above, the usual cause is a shorted ignition switch.

If the above checks out as it should, and the engine dies out when throttle is applied or won't idle, it is usually due to one or both of two things. The carburetors are fouled, in which case the cure would be to remove, clean, and rebuild them..... or the timer base under the flywheel is sticking which would result in a retarded spark. If the engine will not fire/start at all even though you have the proper spark and compression, it's usually due to fouled carburetors.

To check the timer base for sticking (Engine Not Running), spin the prop to align the shifter dog with forward gear and while doing so, put the engine into forward gear. Now, while watching the timer base, slowly apply throttle clear up to full throttle. The timer base should move smoothly all the way up against the black rubber cap that is atached to the end of the full advance spark setting screw. If the timer base sticks, find out why and correct that problem.

Usually any sticking of the timer base is caused by one of the four retaining clamps being slightly too tight. Putting a very thin washer under the clamp cures that problem. Some boaters use a thin screwdriver to bend the clamp upwards slightly but I prefer the thin washer. The sticking can also be caused by having a faulty stator start to melt down, resulting in a sticky substance dripping down on the timer base nylon retaining ring.
 

CHEF06

Cadet
Joined
Oct 1, 2006
Messages
25
Re: Broken wire on rectifier.

Thanks for the reply. Doesnt really answer my question but, I have done a compression test already and have 100psi in all cylinders. I can't do the rectifier test because the red wire on it is broken. I basically wanted to know if the briken red wire on the rectifier could be the cause of the two cylinders not firing? Thanks again Mike
 

F_R

Supreme Mariner
Joined
Jul 7, 2006
Messages
28,226
Re: Broken wire on rectifier.

Not much need to test a rectifier with a bad lead.

Obviously it will prevent the alternator from charging the battery. However, the motor does not run off the battery so it should have no effect. The stator does have coils for the alternator and different coils to drive the ignition, all incorporated into one assembly.
 

rebuilt

Petty Officer 1st Class
Joined
May 11, 2007
Messages
276
Re: Broken wire on rectifier.

Even if the red wire is broken, can't you get the tip of your ohm meter probe to the last part of the good wire? But like previously mentioned, recfifier is part of charging circuit. Good luck, KR
 

mikesea

Lieutenant Commander
Joined
Oct 1, 2006
Messages
1,830
Re: Broken wire on rectifier.

rectifier has no effect on your spark,I would suspect a bad powerpack if the bad cyl.are on the same side,you can switch the paks and if the bad side becomes,you proved your prob.be sure to clean all grounds to packs and coils,besure if your coils have the small wires clip on like a spark plug make sure the connections are rust free
 

CHEF06

Cadet
Joined
Oct 1, 2006
Messages
25
Re: Broken wire on rectifier.

Thanks guys. I will be replacing the rectifier and switching the power pack around to see if that is what it is. Ill keep you posted.
 
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