1973 Johnson 65Hp tilt/trim problem

[Aussie Rob]

HI,.

I have a 65HP 1973 Johnson with a tilt trim that wont hold position - I am assuming the ram needs new 'O' rings

I cant seem to find any parts list etc on how to fix these - or is it a case of pulling appart and heading down to the nearest hydrolic store?

I have the short trim motor/pump that gets wider at the botom.

also the screw at the base - which i believe is a manual release is frozen.. and is crumbling when i try to turn - suggestions?

Regards

Rob.

 

[Snoopy Joe]

Re: 1973 Johnson 65Hp tilt/trim problem

It sounds like the screw your talking about could be the problem. Is it opened or is it closed ?

 

[Aussie Rob]

Re: 1973 Johnson 65Hp tilt/trim problem

I think the problem i have is the 'o' ring in the push cylinder needs replacing - but i cant get the pins out to get the cylinder open.

 

[RRitt]

Re: 1973 Johnson 65Hp tilt/trim problem

most likely the crumbling rubber around MRV is just there to keep debris from collecting in the hole. In later years, they just left it out. underneath the crumble should be a snap ring. make sure that the MRV is tight but not overtightened. It is not replaceable. If you round off the head of MRV then you might have to settle for the really cheap and crappy chinese stuff.

chances are much greater that the problem is in your pump than ram. bottom of ram should be a 3/16" invertered flare fitting. this is same fitting used on most US auto brakes. Most NAPA stores have a wide selection of couplings and plugs to fit. lift eninge and block in place. remove lower tube and plug port. remove engine blocks and see if it falls. If it does, then ram is bad. if it doesn't then pump is bad. pump can be rebuilt of replaced for under $100. check ebay for chrysler force valve body. if you have smaller pump then it is interchangeable with chrysler. If you have larger pump then anybody who can fix chrysler force can also fix yours.

if the ram falls then a picture of ram(s) are needed before I can say anything. in general, you don't rebuild rams because system falls. You rebuild rams because oil is seeping out of top. If oil seeps out when the ram moves in one direction, then water gets pulled in in the other direction. Most trim system have internal parts that are not replaceable and the water can turn expensive rams into worthless trash. In general, when a system drifts down then you fix the pump first.

 

[Aussie Rob]

Re: 1973 Johnson 65Hp tilt/trim problem

Well an update - to hopefully help those who read after the event.

I gave up on manual letdown screw and pulled the rest of the pump apart.. I took the 4 screws out while the pump assembly was still atached to the leg. I couldnt get the oil lines out of the unit so I just flexed the unit down to be able to work on it.

Found a lot of gunge (old thick oil) and fluf etc. so I cleaned it all up and put it all back.
WARNING!!! there are 3 springs, 4 tiny balls (ball bearings) and a couple of washers. when the final bolt lets go they go everywhere.

Its not to hard to work out what goes where. I also pulled the valve and cleaned under it too (thats the small piece in the round recessed ring)

Gave it a good clean - droped the leg and let it flush some of the oils out.

I put it all back together and found I had to take pump motor off leg to get the drive spindle to line up.

AnywaY got it all back together and on the leg. ran the leg up and down a few times refilling each time to get rid of any air bubbles.

Finally I was happy that the air was out and it was full. The leg stays where i put it and it doesnt drop even with me pressing down on it.

Very happy indeed. I had to flex the lower mounting to over 90 degress to be able to mount the inner top plate with all the balls and springs in the right place. - Very fiddly. I would recomend an old sheet or a good floor to work on - took me an hour to find one of the bits in the dirt driveway when i dropped it.

 

[RRitt]

Re: 1973 Johnson 65Hp tilt/trim problem

good job. 99 out of 100 mechanics would never have gotten it to work again. 30 of them would have ruined the motor while they were at it. I tip my het to you. You are obviously good with a wrench.