1977 OMC cooling problems

[LTP]

I bought a 1977 tri hull knowing as is(big mistake) when i bought it, the engine(ford 302 175hp) didn't run but would crank. The engine now runs great, but after making the needed repairs to the engine i noticed that when the drive when into gear the prop didn't spin. The engine has never been run for more than 30 seconds at a time since i have had it since i noticed this problem early on and knew that this wasn't a good sign. I went through the shop manuals and deduced that the upper drive was bad since the lower unit seemed to be good. I disassembled the the outdrive and the upper unit was toast completely froze up, the former owner apparently didn't understand the concept of oil, because all the teeth where completely gone on all the gears.
the lower unit still looked to be in good shape though.
I found another upper unit that was only 2 serial numbers off and was pressure tested before it was sent to me.
Now for the real problem, now that i have installed it and oiled and greased everything, when i run the motor there is no waterflow to the motor. i took of the trunnion cap and there was water flowing out of it from the hose connector at the bottom but when i would start the motor it would stop flowing? and i am at a lost of what to do, i'm about at my wits end on this boat, and don't think i can sell it for what i need to to be able to come out even. your help is greatly appreciated

 

[whywhyzed]

Re: 1977 OMC cooling problems

The water pump impeller in an outdrive is supposed to be changed every 3 years or so.

 

[LTP]

Re: 1977 OMC cooling problems

But if I replaced the whole upper unit shouldn't that have taken care of the problem because the waterpump and such peices are in the upper unit??

 

[whywhyzed]

Re: 1977 OMC cooling problems

you said it was pressure tested - you didn't say it had a new w/p in it.

 

[Lyndy]

Re: 1977 OMC cooling problems

Although the Water Pump is attached to Upper Gearcase, it is not neccessarily considered part of it. You might want to call the folks that sold the Upper and ask. If it was not replaced, it is best that you do. By your post it would indicate you can probably replace it yourself. The complete kit including the Water Pumphousing can be found on Ebay for under $50. I picked up mine for $45 including shipping. When I had my Upper Resealed, I sent it along with the Upper to have it installed.

 

[LTP]

Re: 1977 OMC cooling problems

thanks for the help,

I'm pretty sure that the waterpump was included when i bought the upper unit. I sent the original unit to him so he could match it up, it was suppose to be nothing more than reinstalling everything and it would run,
so is it possible that he didn't correctly install the pump, or that it was somehow broken in shipment or something along that lines? Or that something isn't sealed completely

 

[LTP]

Re: 1977 OMC cooling problems

just an addition the waterpump was part of the upper unit, and he checked it before shipment and he said it was in good shape,

 

[Coors]

Re: 1977 OMC cooling problems

So, you are saying it is used, not new?

 

[LTP]

Re: 1977 OMC cooling problems

yea it's a reconditioned one, it was done by a guy and i just talked to him and his is stumped to, he told me to just take it to omc dealer which is kinda a big deal cause it means driving a ways and there is always the $$$ issue,
but if the dealer finds that something is defective in the upper unit he sent me he will replace it at no charge. so if anyone has a clue what could be wrong it would be greatly appreciated before i spend big bucks to have it looked at

but now i have another problem, my tilt has gone out completely, i was able to get the drive up luckly, but should i just have the tilt motor replaced when i take it in, because i have already troubleshooted the switches and solenoids etc,

 

[Boomyal]

Re: 1977 OMC cooling problems

....but should i just have the tilt motor replaced when i take it in, because i have already troubleshooted the switches and solenoids etc,

Buying an old boat like that, it is time you get your hands dirty and read a few appropriate posts here on iboat. A new OEM motor ( and I don't know if I would trust the $99 ebay specials) will cost $200+ when all it may need is a removal and cleaning. You could always remove it and take it to your local generator/starter/alternator rebuild shop.

"Dealers" are the very worst place you could take your OMC. You need to find an independant who specializes in the now out of production outdrives.

 

[LTP]

Re: 1977 OMC cooling problems

Thanks for the advice, thats what i did originally, the guy i bought the upper unit from is an older gentlemen who does nothing but collect and repair OMC outdrives,

I'm not exactly sure if the person i would be taking it to is a dealer or someone that is a marine mechanic with lots of OMC expereince, my buddy recommened him and being the weekend i haven't had a chance to call him and find out. i have spent hours looking through shop books and the internet looking for a reason for my water problem and the gentlemen that i got the drive from had no clue, except maybe the lower unit pick up was clogged somewhere in the tube

the only reason i suggested having the tilt motor worked on, when i took it in is that i just put on a new boot and sealed it two days ago and i don't want to rip it, and as long as it was off...... have it pulled out, because i can do and have done most of the work on the boat

 

[LTP]

Re: 1977 OMC cooling problems

hey thanks for the advice about the tilt motor and stuff, but i still haven't gotten a solid answer on the first question and it's the one that is really bugging me.

it is extremely hard to discribe to be helpful to you guys but i will try,
i have a house connected to the lower unit using "muffs' but its like a single muff because it slides over the ventilation/cavitation plate and has like what looks like one of those suction cup things for sticking things to windows that is suppose to sit flush with the outdrive,
well with the water turned on it doesn't seem like very much makes it into the unit period, but when i took the trunnion cap off there was water there, but only a small amount, and even with the motor running very little water was flowing to the trunnion cap, since i just replaced the whole upper unit including the waterpump, i've started to guess that maybe the pick up tube is clogged in some manner or that "muff" doesn't work well or right, because when i unclamped the intake hose at the engine it was bone dry

 

[Lyndy]

Re: 1977 OMC cooling problems

If the water intake is similar to mine, the hole in the bottom cavitation plate is big enough for 1/2" hose to fit snuggly. The 1/2 muff may be letting air in. The previous owners of my boat kept a 2' piece of 1/2" hose with a female end on the boat. They just attached it to whatever water hose was available when they flushed the engine. Since then I replaced the Starboard Trunion Cap with a Hose Adaptor. Water goes to the Engine and the Impeller. Several others on this board have done the same. At this point, I would suspect your Muff. I am sure others will give you their humble opinion.

 

[LTP]

Re: 1977 OMC cooling problems

ok thank you very much i was wondering if maybe that was possiblly the problem i might just take it around the corner to the ramp and back it in out of the way with it still on the trailer to check it out.

 

[Lyndy]

Re: 1977 OMC cooling problems

Be sure to back it in far enough to cover the outdrive with water. Being immersed in water is what keeps the drive cool. Remember not to fire that bad boy up with the Drive in the Up position.

 

[LTP]

Re: 1977 OMC cooling problems

i took the screen off of the intake and was able to force water through system to the engine from there, so i hope that is a good sign
but my tilt motor went out completely i think so i won't know it the problem is solved untill i trouble shoot that again and make sure it is the motor before i pay for a new one.

 

[drakocy]

Re: 1977 OMC cooling problems

any help telling me if i can run my omc without a lower unit installed, using a garden hose adapter to the fitting on the side of the upper,,, reason i want to see if my engine is worth going any further with,,, i have lots to do but do not want to get any further if the engine is junk,,,,, im thinking it shlould be ok,,, as long as water is being forced through... thanks
david