78 grady white with 4cyl omc tilt trim problems

mirage5058

Seaman
Joined
Jun 2, 2008
Messages
60
I picked up a 76 grady white 120 hp omc motor and outdrive i got it running great,the outdrive did not work when i got it also it just swings up and down with no resistence like it is not attached to anything,i put in new tilt motor old one was siezed,motor works now but the outdrive(OMC) does not go up or down even with new working motor you can lift the outdrive up and down by hand the gear is okay i put new oil in gearbox,i dont know what the previous owner did but i know the outdrive should stay in place and you shouldnt be able to lift it up and freely,is the something i am missing to engage the gearbox so the drive will stay in place and raise and lower like it should?Any help would be appreciated when i took the middle gerarbox cover off to clean and check i noticed the clutches seem okay,My main question is why does the l ower swing up and down freely and wont go up and down using motor?
 

Todd157k

Petty Officer 2nd Class
Joined
Jul 12, 2010
Messages
114
Re: 78 grady white with 4cyl omc tilt trim problems

it may be that the hydraulic actuators have a lot of air trapped in them since it hasn't been used in a long time. Do a search for "trim" and you'll find postings on the bleeding procedure. The manuals say you don't have to bleed them, but it takes several cycles to relieve the trapped air. Only they do specify not to over heat the pump motor while doing it.
 

Howard Sterndrive

Rear Admiral
Joined
Nov 5, 2008
Messages
4,603
Re: 78 grady white with 4cyl omc tilt trim problems

he doesn't have any hydraulic actuators. Must be something broken in the tilt clutch housing.

By the way, that ain't trim. If you use it as power trim, you'll trash your ball gears and outdrive.
 

slag

Chief Petty Officer
Joined
Jul 17, 2009
Messages
471
Re: 78 grady white with 4cyl omc tilt trim problems

sounds like you are missing the spiral screw that fits into tilt mechanism. When looking at the rear of the boat, there should be a triangle shaped piece of metal bolted to a round hole area.. (hard to explain). There is a small plug that fits on the end and inside there is the spiral gear. It must engage the pin on the shaft.
 

lmjpsl

Cadet
Joined
Jun 24, 2010
Messages
27
Re: 78 grady white with 4cyl omc tilt trim problems

It could also be the shaft inside the housing in which the ends have broken off.
 

superbenk

Commander
Joined
Oct 27, 2008
Messages
2,033
Re: 78 grady white with 4cyl omc tilt trim problems

I'd say your clutch pack is worn out or in need of cleaning. You can take the shaft & clutch pack out of the clutch housing and remove the clutch plates and soak them in acetone for a few hours. After they've soaked, you air dry the clutch discs, soak them in 30 wt gear oil, then put the whole assembly back together again. Note that you'll need a hydraulic press to get the plates & spring washers compressed so you can put the C-ring back on that holds it all together. Once it's all back together you put the pack and shaft back in the housing & fill the housing with either 30 wt oil or stuff it with marine bearing grease (I prefer the latter since the housing always leaks). Make sure you replace the seals & gaskets on the housing.

Even after you do all that, if the clutch plates are too worn out, it'll still get loose again pretty quick. You'll probably get it tight at first, but once you dunk it and run it for a bit you may find it loose again (I did on mine). If the clutch discs are shot you can find some online (hard to find). Alternatively you can fuse the clutch pack together somehow (ie, a pin driven through the pack), but doing that removes the safety feature of the clutch which is there to let the drive swing up in the event you hit something.
 

superbenk

Commander
Joined
Oct 27, 2008
Messages
2,033
Re: 78 grady white with 4cyl omc tilt trim problems

FYI, this is what happens to ball gears when you use tilt as trim for too long (got my boat with the gears like this):

IMG_2971.JPG
 

mirage5058

Seaman
Joined
Jun 2, 2008
Messages
60
Re: 78 grady white with 4cyl omc tilt trim problems

Thanks for all the info,This is what i have done so far,the spiral worm gear in the case is in correctly,the shaft going from motor to worm gear is all there no breaks,i took the clutches out they are worn i am assumming because when i pulled the whole assembly out the clutch pack is real sloppy on the shaft,i am not sure if the guy i got the boat from took them apart before i got it from him but it looks like someone has messed with it,im not sure the clutch pack is even together right or all there,i do not have a manual that shows it,i did take them apart and cleaned them along with case,also check the brass gear for wear it looks fine,you mentioned i may need alot of pressure to put retaining ring on but there is no resistance at all the ring goes on with no problem,so i am guessing there is definately a problem there,when i took the clutch pack out it had two,spacers by the cover end then a clutch then then spacer,clutch,spacer ect.Any picts or diagram would help,the guy i got the boat from butchered it it took me all summer to fix wiring,rebuild trim and tilt motors,tune up new igintion points,plug wires ect,
 

superbenk

Commander
Joined
Oct 27, 2008
Messages
2,033
Re: 78 grady white with 4cyl omc tilt trim problems

Sounds like you're definitely missing some parts. Either clutch plates, one of the heavy washers or the spring washers. You definitely need a press to put it back together (or a strong vice & some creativity). If it goes together without any difficulty in your hands, it's not going to do anything at all. The clutch plates need a lot of friction in order to do what clutches do.
 
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