1970's 100 HP Starflite Electronic Shift Help

boaterdude83 · May 15, 2008

Hey everyone - I'm new to the forum, but generally i'm used to working on my mercruiser. A friend bought a boat though and it has on it a 100hp Evinrude 100hp Starflite. It has the electronic shift in it. The lower unit was pulled apart to replace the impeller, and ever since they said it wasnt right. I got the motor running, starts right up now, but i had no water coming out (it was missing that plastic tube that goes from the water pump to the pickup) and when it was running, it was in foward. Pushing foward or reverse didn't change anything. Can anyone tell me how the shift celenoid works, or perhaps maybe its back in wrong? The last owner did have them out. He said they slide out with a few bolts and the cover comes off in the lower unit. Thanks for any help,
Joe

boaterdude83 · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

And in addition the model number is 100293. Can anyone tell me what year this motor might be? Thanks again!

F_R · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

1972. So why did the guy have the solenoids out anyway? Because it wasn't shifting??
Briefly, here is how it works: It actually is shifted by hydraulic pressure created by an oil pump in the lower unit. That is why it has to be running in order to shift. There are valves in the oil pump that are closed by two solenoids when you push the shift buttons. Closing one or both of those valves directs oil pressure to cause neutral or reverse shift.
#1 Check your gear oil. It doubles as hydraulic fluid.
#2 Troubleshooting this system should always begin with a voltage check at the shift wires going to the lower unit. With the wires connected, and key on, push the neutral button. You should have battery voltage on the green wire. Push reverse and you should have battery voltage on both the green and blue wires. Shift through all gears a whole bunch of times for consistancy. Those push button switches are notorious for being bad, and unavailable at a reasonable cost.

I'm sorry, but taking the solenoids out is a dumb move.

boaterdude83 · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

The guy said it did run good, but needed the water pump. He said he had to pull the celonoids out to drop the lower unit. When my friend matt bought the boat, (600 buks) He said all you had to do was put the lower unit back on. They did that and it didn't work. He said they had to put the celenoids back in as well. I just pulled the lower unit off (pulled the wire through) and I need to put in the 2 plastic tubes for the water, and figure out the shifting. I will test the shift wires now, but I was thinking they may have did somthing with the celenoid. Ive never pulled one apart, so dont really want to, but thats where I figured the problem was occuring.

tashasdaddy · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

if the solenoid rods are not in the correct position, the will not activate the valves.

boaterdude83 · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Ok. Well while i have the lower unit off, is there any way i can tell if they are in the correct position? Also On the water pump, it looks as if there are 2 water tubes coming off the pump housing. Is this true? Do both of these get the plastic tubes? The shifter wires do get the correct power to them. After I can get this lower unit back in in right order, the boats ready to go, and I can get it out of my yard haha. Thanks for all your help guys.

F_R · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

The solenoids are installed one at a time. Do the lower one first, and if it is installed correctly, the plunger will be flush to 1/64" below the top of the solenoid body. Then the same with the second one. Then there is a wave washer on top to hold them down, then the cover plate.
So he had to remove them to remove the lower unit? Yeah, uh-huh, right.
The plastic tubes are only guide tubes to guide the copper tubes into the water pump because you can't see what you are doing in there. Once the lower unit is on, the guide tubes just go along for the ride.

patrick4266 · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

I have a 1972 85hp rude which has the same lower unit as yours. I did not see any one mention using the right lube which is "c" or premium blend. If you need any help with putting on that lower unit send me a private message and I will give you my phone number. I have done it a few times and they can be tricky.

jay_merrill · May 15, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

I have not yet had a reason to take the gearcase apart on my 1972 65hp Johnson, but I understand that one of the common mistakes that people make when changing a water pump is to let the gearcase fall, thereby damaging the shift wire connector. As FR suggested (did I note a hint of sarcasm in his comment?

), it isn't necessary to pull the solenoids in order to remove the gearcase from the exhaust housing - there is a connector in the shift wiring that allows the wires coming from the solenoids to be disconnected.

Aside from the issue of making sure that the solenoids are re-installed properly, you need to check the condition of the connector. If it is damaged, you will have to go on a hunt at OMC/BRP dealers, because this part is no longer available from the factory. It is a "dealer direct" item which, as I understand it, means that if you get lucky enough to find a dealer with one as New/Old Stock (NOS), you will pay whatever that dealer feels he/she should get for the part. You might get lucky and get one for an old price or, you might end up paying a "stupidly high price" just because there aren't many of them around any more.

boaterdude83 · May 16, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

I know the guy who owned the boat before, and he does like to try to fix stuff himself, but i guess he didnt know the wire pulls through from the top. Hopefully i'll be getting it back together sunday. I thank you all again for your help. I'd love to get this boat out of my driveway, and as for my friend, hes a first time boater with this boat. He'll be buying the first few rounds at the bar after this jobs done.

boaterdude83 · May 18, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Ok. I pulled off the celenoid cap, and cleaned everthing up with wd40, and made sure the 2 rods moved cleanly. This is how I put it together:

First celonoid(blue wire as it was longer) with the rod in it. The rod sat almost flush in the round metal celenoid. Than a plastic washer type thing, than the next celenoid(green, shorter wire) than the 2nd rod. I didnt have any type of washer that went on top though, than put the cover back on. I havn't put it on the boat yet, and had a few last questions. I understand that the plastic tubes are to line up the metal ones. I need to get me 2 of them. 2nd, Why are there 2 copper tubes, and 2 places for them on top of the water pump? I thought there was only one. Any ideas? Thanks everyone.

F_R · May 18, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

The solenoids won't work without that wave washer to hold them down. The solenoid body will just lift up instead of hold the rod down to close the valves.

The water pump supplies lake water to circulate through the powerhead, then it is presented to a thermostat. The thermostat decides if it is warm enough and if it isn't warm enough it goes back down to the second water tube and is recirculated back up again for another pass through the powerhead. This continues till it is up to proper operating temperature, then the thermostat opens and the hot water is discharged and replaced with fresh cool lake water. This is sort of an oversimplification of the system. In actuality, the thermostat constantly opens and closes as required to maintain the proper temperature.

If you think about it, your car works the same way. That is why you have two hoses going to the radiator. Your outboard just uses the lake as a "radiator", that's all.

boaterdude83 · May 19, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Ok I understand that system with the water. Does the water pass out of the exhaust when the motor is cold than, or only when the thermostat opens?

Also - The washer that keeps down the 2 celenoids - Is it that plastic spacer that went inbetween them, or is that just a spacer, and I still need the washer? I don't see any washer around, but If it was apart, I could be missing parts.

F_R · May 19, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Because there is a partial bypass for the thermostat, some water will go out the exhaust even if it is closed. This is necessary in order to keep the exhaust area cool.

It gets the plastic washer between the solenoids AND a wave washer on top.

boaterdude83 · May 19, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Ok. Now I have a new problem at hand. Since the boat has been in my hands, I have never seen any such washers, and I don't see any around the boat at all. Any Ideas where I could get one, Or What I could use?

boaterdude83 · May 19, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Looking at the breakdown, the wave washer looks to only hold the solenoid down from the top. Can I use any spring/wave style washer as long as its close to the right size? It doesnt look to do anything for the plunger.

F_R · May 19, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Just so it holds the solenoids down.

boaterdude83 · Jun 8, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Well I finally got around to putting the boat back together. I know the 2 water tubes are lined up with the water pump, but i still dont' get any water out of the exhaust on the motor. In addition, It still stays in foward. On a lighter note, the motor started right up and ran beautifully. If only the lower unit would work properly... Any suggestions?

F_R · Jun 8, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

Go back and read my May 15th reply explaining how to do an electrical check.

boaterdude83 · Jun 9, 2008

Re: 1970's 100 HP Starflite Electronic Shift Help

I checked the voltage as soon as the lowerunit wasn't shifting. They voltages were both correct. I also checked continutity from the conections to the outdrive and they seem to be all alright. Thanks for all your help.

1970's 100 HP Starflite Electronic Shift Help

Seaman Apprentice

Seaman Apprentice

Supreme Mariner

Seaman Apprentice

Honorary Moderator Emeritus

Seaman Apprentice

Supreme Mariner

Chief Petty Officer

Vice Admiral

Seaman Apprentice

Seaman Apprentice

Supreme Mariner

Seaman Apprentice

Supreme Mariner

Attachments

Seaman Apprentice

Seaman Apprentice

Supreme Mariner

Seaman Apprentice

Supreme Mariner

Seaman Apprentice