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'1976 235 OMC Electric Sterndrive Help

DangerousDane

DangerousDane

Member
I just bought my first boat, 1976 24ft Fiberform Cabin Cruiser OMC 235hp V8 w/ Electric Shift Sterndrive. Its in great shape, and I pretty much stole it for $3100.
She won't go into reverse tho, and the prop trim works but sometimes you have to bang on the clutch with a mallet.
These are the only problems I'm aware of, but I haven't been out on the water yet. I want to fix reverse before I go out on the lake and crash into the marina trying to dock.
I've gathered this much from the forum...
Tomorrow morning I'm going to go test the gears by turning the key on motor off, put in forward and try to turn the prop backwards and vice versa for reverse. Then I'll try to see if its getting the electric signal from the shifter for reverse at the drive and trace it out if need be.
Any thoughts would be appreciated. I found http://www.sterndrive.info/index.html for drawings and parts so maybe I can pull this off if I can figure out whats broken.
 
Re: '76 OMC Electric Sterndrive Help

Sounds like a bad electrical connection, or the reverse coil in the lower end is out. Check for electrical continuity at the connection between your wiring harness to the coil connector. Had the same problem a few years back. Lost my forward coil and drove home backwards, beets swimming.
 
Re: '76 OMC Electric Sterndrive Help

ok an electrical issue should be easy enough for me to figure out. I hope its as easy as a bad coil. Thanks IB
 
Re: '76 OMC Electric Sterndrive Help

I found this that the chief posted a while back for the tilt...
6- On the out drive port side, there is a clutch housing. Four screws hold on
cover. Pull that cover. May be full of water. They all leak.

Two things you can do at this time.

A- Clean out the housing with clutch installed.

B- Remove the clutch and rebuild the housing. New seals.
Click to expand...

I'll open up the clutch tomorrow too and repack it.
 
Re: '76 OMC Electric Sterndrive Help

Jeez you paid 3100 for that barge ?

Ok you found my post, Good. If you need help just post here.

Could be the coil, could be the switch that you push to go in the direction that is not working.

Start at the switch. Work your way back.
 
Re: '76 OMC Electric Sterndrive Help

With the key on and the drive in forward the prop will not spin backwards. But when the drive is in reverse the prop spins freely in both directions. Would that imply an electrical malfunction?

Thanks for your time Chief
 
Re: '76 OMC Electric Sterndrive Help

DangerousDane said:
Would that imply an electrical malfunction?
Click to expand...

electrical or mechanical

that test didn't narrow anything down.

start with an ohmmeter
disconnect the knife connectors and measure
4-8 ohms from the reverse wire with reference to a good ground or batt neg.
 
Re: '76 OMC Electric Sterndrive Help

Sir: i must strongly suggest you buy at least a seloc manual available at any west marine or online. The most basic of instruction will be included in such manual.

#3400 in the right hand corner seloc will do. Furthermore i would do what Hy suggested.

The test he suggests will give you a base to rule out the electrical vs mechanical issue it may be.

Hopefully it's just a wire.
 
Re: '76 OMC Electric Sterndrive Help

Ok I ordered the Seloc #3400. That ought to come in very handy. Thanks.

I found that test on another thread for a similar problem, I just didn't want to come on here and say 'whats wrong with my boat'... I probably shouldn't bother you guys too much until I get the seloc and read thru it, now that its on its way.

I spent this morning rewiring the trailer so I didn't get a chance to check out the reverse problem, but I'm going back after lunch to do it. Its been 115 F the last 3 days here... a little cooler today tho.

Thanks guys
 
Re: '76 OMC Electric Sterndrive Help

I followed the wires from the gear selector to behind the gages and it went into a 6 pin harness with 5 wires in it numbered 1-6.

on the motor side of the harness:
#1 6.5 ohms with ign off, open to ground with ign on (didn't think to check for +12v)
#2 10.5 ohms ign on or off
#4 8.5 ohms ign on or off

the other two wires in the harness #3 & #5 showed open to ground on all wires ign on or off, forward or reverse.

on the gear selector side of the harness:
open to ground on all wires ign on or off, forward or reverse.
I didn't think to check for continuity between all the wires to see if a ground was being passed by the switch itself.

Chief when you said 'the switch that you push to go in the direction' do you mean the knob you pull out for neutral and the switch on the backside of it? That mechanism seems to be working, with the knob out it doesn't turn the switch on the backside, and with the knob in it turns forward for forward and backward for reverse. I'll test it for continuity like I should have thought to do when I was there earlier.

without the Seloc book I can't tell what's what. Seems like I got both coils at the harness, does it sound like the coils and the wiring to the coils are ok?
 
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Re: '76 OMC Electric Sterndrive Help

I got the manual (thanks cheif), and i found a disconnected blue wire im hoping fixes reverse.
I'm trying to remove the tilt motor because its not working, and after removing the two long 3/8" bolts the armature shaft is stuck in the hammer blow coupling. The book just says pull the tilt motor off, but it wont budge. I figured I'd ask what you guys thought.
The motor had oily greasy sh*t in it, I dont even know if its fixable...
 
Re: '76 OMC Electric Sterndrive Help

I don't think theres room to bang on it but I can use a screwdriver to pry it out of the coupler.
I don't see a gasket, I see a round metal piece with about 6 slits cut in it and the armature shaft goes thru the center of it presumably into the hammer blow coupler. The armature shaft will slide forward about a half inch before it stops. I figured to just pull and pull but I don't want to damage the blow coupler either.
 
Re: '76 OMC Electric Sterndrive Help

Thanks for the link Chief. I'll order a gasket as soon as I get the tilt motor off in case I damage the hammer blow coupling when I'm in there or anything else. I'll be careful!
 
Re: '76 OMC Electric Sterndrive Help

Ok got the motor off, that was easy. I guess I was just being over-cautious. The thing is soaked in oil, I dont know how you'd get it clean without solvent. Good news is the hammer blow coupler looks great.
As soon as my camera is charged I'll post some pics for your entertainment.
 
Re: '76 OMC Electric Sterndrive Help

Here's what the tilt motor looks like. The brush kit is $45 with shipping on ebay, the whole motor is $65 w/ free shipping so I think that makes it easy. I can't see a picture of either of these brush kits for $10 or $11.47 from marineengine.com. I'm thinking just replace the whole thing for $65...
10-07-10%20-%20Tilt%20Motor%20001.jpg


10-07-10%20-%20Tilt%20Motor%20002.jpg


10-07-10%20-%20Tilt%20Motor%20003.jpg


10-07-10%20-%20Tilt%20Motor%20004.jpg
 
Re: '76 OMC Electric Sterndrive Help

Just bought the new one from the link above for $65. That price is almost too good to be true. I'll fix this one up for a backup, do you guys think the $10 brushes from MarineEngine.com would make this work again?
 
Re: '76 OMC Electric Sterndrive Help

no get the new motor. Don't forget to install the gasket like the last guy who replaced it and pack the housing with grease.
 
Re: '76 OMC Electric Sterndrive Help

Glad to see your on the way to getting it figured out. We still have maybe two months left of good boating weather at least where I'm located. Oye, I see your in AZ you probably can boat most of the year down there then.
 
Re: '76 OMC Electric Sterndrive Help

chiefalen said:
no get the new motor. Don't forget to install the gasket like the last guy who replaced it and pack the housing with grease.
Click to expand...
I'm definately using grease in the clutch housing instead of oil... thats a great idea. Thanks for the tip.
Hopefully a new gasket and grease in the clutch housing will keep oil from getting into the new motor.

floater1 said:
Glad to see your on the way to getting it figured out. We still have maybe two months left of good boating weather at least where I'm located. Oye, I see your in AZ you probably can boat most of the year down there then.
Click to expand...
Yes, most of the year for sure. The trade-off is the deadly heat. Its been right at 110-115F for almost 2 weeks and the humidity is rising as we go into monsoon season. Its been torture to work on the boat when the sun is overhead. Fortunately I still have about half of the summer left which is about 3-4 more months of good swimming weather.
But I have to get her on the water 1st! It's looking like next weekend finally.

The trim was working intermittently with a rubber mallet assist when I bought her, but when I got her to storage it wouldn't work at all. Once I get this new motor in I can lower the prop all the way and see if reverse works. The reverse wire speed clip (with slider that holds the wires together) between the intermediate and the reverse solenoid had come undone. I'm really hoping that was all that was stopping reverse from working. A freebie!
Thanks for your input everyone!
 
Re: '76 OMC Electric Sterndrive Help

Well, I got everything working in time to find the engine oil had plenty of water in it. :eek: Luckily I only put about a half-hour on the motor.

I finally got her out for a test trip to find out what all is wrong with the boat and what I still need for a good trip. I powered out about 200 yards from the ramp to a nice beach, and stayed overnight. The rain came down hard for a few hours while we took refuge in the leaky cabin (another project now). The next morning the hull had quite a bit of water in it which I bailed out before heading out. We were heading to the marina for a nice breakfast and I notice that the motor would not spin faster than approx 3300 rpms. Shortly after that my brother notices some steam coming out of some kind of breather on top of the port valve cover! The intake manifold had standing water on it (I guess the hatch to the motor compartment must leak onto the motor) that we thought was the culprit however the steam seemed to vary with throttle application and it was evident that it was coming from the breather. So I kill the motor and pull out the dipstick. There was white foamy milk covering the whole thing. If you pull off the breather you could see water spots inside the valve cover...

Now this is where I realize I'm an idiot and I never checked the oil up until this point. Even tho I kept saying 'we need to go thru the whole maintenance section of the Seloc before we go out, the outdrive could have water in it's oil'. I must have said it 3 times and thought it 100, but somehow we got excited and overlooked it. Little did I know the freakin engine could have water in it's oil.

So I don't know if the oil was milky when I bought her, if the guy I bought it from knew this and had just put fresh oil in to sell it and my 1/2 hour of screwing around did it, or if the downpour we endured could have gotten enough water in the oil. I would guess the guy I bought it from had no idea about the oil's condition based on the broken reverse gear being a disconnected wire, so its probably been this way. However I think a half-hour of use could probably sufficiently water down a fresh oil change to where it is now if it's a head gasket and if he changed the oil just to sell the boat.

Anyway, I've scoured the Seloc manual a few times now, and was just wondering if you helpful fellows had any suggestions that might ease the pain of fixing my milky oil woes. I'm thinking head, intake, and valve cover gaskets, what about exhaust? The whole boat has only 780 hours on it so its hard to imagine a head gasket needing to be replaced already but thats the first thing I think of.
Many many thanks in advance gentlemen.
 
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Re: '76 OMC Electric Sterndrive Help

pressure test the cooling system

recent thread on how to do it:
http://www.marineengine.com/boat-forum/showthread.php?p=294438#post294438

to pressure test, remove the 2 hoses heading for the exhaust manifolds and block them with a bolt and clamp (red x's)

remove the hose from the intermediate and introduce air pressure in the direction of the green arrow- 15 psi max.

you'll hear any internal or external leaks

searay.jpg
 
Re: '76 OMC Electric Sterndrive Help

ohhh man I hope mine doesn't end up like that other guys did.... The previous owner had it for 3 months and the owner before that had it for 15 years. I talked to him on the phone when I bought the boat about the title for the trailer and the AZ Game & Fish title for the boat cuz the 3 month owner never transfered ownership into his name. I doubt they're scamming me with a bad engine but I won't know until I do this pressure test.
This was exactly the help I hoped for. I'm glad I asked before I tore apart the damn engine. Thank you Hystat.
 
Re: '76 OMC Electric Sterndrive Help

Ok I like to start by saying thank you again to Hystat and Chief, you guys have saved me big bucks and a lot of headache.
Now to the news of the day.
I did as Hystat instructed...
10-08-02%20Pressure%20Test%2007.1.jpg

10-08-02%20Pressure%20Test%2009.1.jpg


And.....No Leaks! I left it pressurized for about 5 minutes to make sure and listened all around the motor for air escaping. Nothing! No sound of air coming in the line at the air compressor either.

So I'm thinking a compression test and leak test each cylinder. Which I don't have tools for so I'll get them tomorrow and let you know how it works out.

Any other ideas???
 
Re: '76 OMC Electric Sterndrive Help

Oh yeah, I felt around the bottom of the oil pan for a drain bolt... I couldn't find anything except a weird looking one on the side of the pan on the port side which wouldn't drain out all or much at all of the oil. I know when these came new you had to pull the motor to change the oil but I figured every owner would have put the kit on. I don't know what the kit looks like to see if this old girl has it installed. If it doesn't, this oil could be really old or maybe original.
What can I look for to see if I have the oil changing kit installed?
I have access to a forklift so pulling the motor isn't impossible for me. If I'm already pulling the top of the motor off for new gaskets it shouldn't be much more work to get the motor out to install whatever kit goes on for oil changes.
 
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Re: '76 OMC Electric Sterndrive Help

Its been a few weeks now, I got some more work done finally.

I got situated so I could run the boat at the storage facility with a 55 gal plastic drum full of water.

I warmed up the motor and pressure tested the block again and it held pressure again.
I took all the plugs out and #3 & #4 (back 2 on starboard) had water on the electrode. #2,#3,#4 plugs look rusty too. When I hit the crank water shot out of #3 & #4 for the first 5 cranks or more!!! I didn't have water hooked up at this point. How the F does this motor run? I thought it would lock up with that much water in the cylinder. Did water get in the exhaust and then blow the head gasket trying to compress water?
It looks like the guys who I bought it from had just rebuilt the exhaust manifolds...they have fresh blue paint on 'em and new copper RTV sealant too.
 
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