1977 rude powerpack question?

Joined
Sep 14, 2006
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20
hi guys, had my boat out the other day and all ws going good until i started getting surges in power (rpm changes). my motor is a 1977 115hp rude. next day i cranked her up at home and found a bad wire shorting out (thought i fixed it) not. i had her running and all of a sudden the motor died (no spark). i've done a compression test all are 115 except 0ne is 105. i've checked the black w/ yellow wire coming from the powerpack to the ignition switch, no shorts. i disconected the black and yellow at the powerpack and tried to crank the motor it fired once but thats it. i reconnected the black and yellow wire and it fired once again. i did an ohms check at the powerpack where the black and yellow wire hooks up and ground and reads open but if i reverse the leads i get a reading of .750 ohms. any thoughts before i buy a new powerpack?? any help appreciated!!!
 
Joined
Sep 14, 2006
Messages
20
Re: 1977 rude powerpack question?

rickdb1boat said:
Which wire was shorting out?

the red wire from the starter solinoid where it hooks up to the terminal block w/ the red rectifier lead. i checked the recitifier and it tests good. i'm afraid i fried something!!
 
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Sep 14, 2006
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Re: 1977 rude powerpack question?

done some searching on this forum and today i'm going to try a different battery, (the one i've always used is only 550cca) seems these old v-4's need alot of cca's to generate enough rpm's. will let you know what i find out. oh by the way, while searching for my shorted wire i did clean and retiighten all grounds and hot wires. my fingers are crossed!!!
 
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Re: 1977 rude powerpack question?

okay i'm stumped!! here's what i've done so far; cleaned all ground connections, hot wire connections, done compression test (within specs), replaced powerpack, used an 750cca battery for cranking, pulled flywheel, stator looks good no melting green coating still in tact, timerbase looks suspect tho, one of the sensors looks to have been rubbing on the inside of the flywheel, put an ohm meter between sensor wires and shows short, put ohm meter from sensor to ground shows short. my question is; is there any way to test the stator or the timer base while removed from motor w/ just an ohm meter??? anyone tried this??
 

rickdb1boat

Supreme Mariner
Joined
Jan 23, 2002
Messages
11,195
Re: 1977 rude powerpack question?

Here's some reading:

No Fire at All:
(Note: If the engine fires with the spark plugs out but not with them installed, the timer base is either weak or the
engine is not spinning fast enough. See # 6 and #8 )
1. Disconnect the black yellow kill wire and retest. If the engines' ignition now has fire, the kill circuit has a faultpossibly
the key switch, harness or shift switch.
2. Disconnect the yellow wires from the stator to the rectifier and retest. If the engine fires, replace the rectifier.
3. Check the stator resistance. You should read approximately 500 ohms from the brown wire to the brown/yellow
wire.
4. Check the DVA output from the stator. You should have a reading of at least 150V or more from the brown
wire to the brown/yellow wire (while connected to the pack).
5. Check the timer bases resistance from the #1 sensor wire to the #3 sensor wire, and from the #2 sensor wire to
the #4 sensor wire. Reading should be 10-20 ohms on each set.
6. Check the DVA output from the timer base. A reading of at least 0.5V or more from the #1 sensor wire to the
#3 sensor wire, and from the #2 sensor wire to the #4 sensor wire (while connected to the pack) is needed to fire
the pack. If the output is low, you may try to reset the air gap between the timer base sensor and the triggering
magnet using a Sensor Gap Gauge (553-9702) or use the following procedure:
a) Loosen the two mounting screws on the sensors and the nuts located in the epoxy on the outside of
the heat shield of the timer base.
b) Slide the sensors in toward the crankshaft until the sensor touches the stop boss located at the base
of the sensor mounting area. Tighten the mounting screws.
c) Coat the face of the sensors with machinists bluing or equivalent.
d) Install the flywheel without the key and rotate the flywheel at least one full turn.
e) Remove the flywheel and check to see if the trigging magnet struck the face of the sensors. If it
did, back the sensor out approximately 0.005” and repeat steps c, d and e.
f) If the ignition fired, finger tight the nuts on the outside of the heat shield and coat them with RTV.
g) If still no fire, replace the sensor.
7. Check the DVA voltage on each black/white wire to engine ground. You should have a reading of at least 150V
or more (while connected to the pack). If the reading is low, disconnect the trigger wires from the pack and
recheck the black/white terminals on the pack. If the voltage jumps up to an acceptable reading, the timer base
may have a problem in the internal wiring (possibly a thin spot in the insulation on one wire).
8. Check the cranking RPM. A cranking speed of less than 250-RPM will not allow the system to fire properly.
 
Joined
Sep 14, 2006
Messages
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Re: 1977 rude powerpack question?

rick thanks for all the help!!! i did all the tests you described and still no fire. but i started all over from step one and guess what i found. when i was cleaning all the ground cables i put the ground that is suppose to ground the coil assembly on the engine so all the coils had no way of grounding( i'll wear the dunce cap for an hour, but then i'm off fishing). i guess the lesson learned is never give up there's always a solution to every problem. thanks again rick
 
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