Manual Trim Unit - 48 Special

[N4WJT]

The manual trim unit on my 1992 Johnson 48 Special is not working correctly. When the latch is released, it's almost impossible to 'raise' or 'lower' the motor. Previously, it had been lowering OK, but there was no 'assist' during raising. Is this unit serviceable? Are replacement units avaiable?

 

[imported_lorin]

Re: Manual Trim Unit - 48 Special

This motor has the gas charged tilt assist cylinder, one of the less wonderful creations from OMC. If you don't tilt your motor very often this system works OK. I used to work at a shop that had a lot of commercial fishermen customers and many of them who had this motor would eventually remove the whole tilt sytem and use a block of wood to keep the motor propped up. One big problem is that the cable that activates the cylinder stretches so much that when you move the lever to tilt, the cable doesn't open the valve in the cylinder enough to allow any tilting. Also the cable would pull out of the cheap plastic blocks that are used to hold it in place, so again the valve in the cylinder is not opened enough. You can test the cylinder itself by using a pair of pliers to manually lift the little part on the cylinder that the cable attaches to. So suspect the cable first and hope the cylinder itself hasn't failed as it's quite expensive

 

[N4WJT]

Re: Manual Trim Unit - 48 Special

So the cylinder has 'gas' in it. I thought maybe it was hydraulic fluid. There are two openings in the unit with pipe plugs in them. I had wondered if it needed fluid? If it's gas, I guess it won't not be a good idea to take the plug out. I understand what you mean about the plastic fitting on the cable end. I had to replace it a couple of years ago. Seems like that length adjustment is real sensitive. Also wondere if I should try to readjust?

I appreciate you help.

 

[imported_lorin]

Re: Manual Trim Unit - 48 Special

The cylinder contains both fluid and gas. The gas is under a lot of pressure. There is no adding fluid to the cylinder and no parts in the cylinder can be changed or bought separately. As I mentioned, the best way to test the cylinder is to use pliers to move the part on the cylinder that the cable attaches to. I think it's called a slide valve. You must remove the nut (if I recall, the nut is plastic) that attaches the cable to the cylinder before you can get at the slide valve. Again-it's usually the cable that stretches and the cable ends and blocks that hold the cable that mess things up. And as you said, the adjustment is quite sensitive.

 

[mikesea]

Re: Manual Trim Unit - 48 Special

FYI,if you didnt know,there are a few companies that make units ,nice and light ,it mounts to your boat,motor to it and gives you complete trim and tilt.the boat will perfprm better ,ease of lifting and well built. I think CDC,I have put them on customers that wanted tnt .

 

[Navanax]

Re: Manual Trim Unit - 48 Special

Re the sensitivity of the cable adjustment. I replaced the plastic "shell" (Part 334153) that connects the tilt assist cable to the boat about two years ago. End of this summer it was getting hard to raise and lower. I tightened it down from 11 threads showing to 9 threads showing and it works like a charm. Rinse this whole area really well after salt water, keep some WD40 on the cylinder arm and moving parts, and order a backup shell. They're less than $5 and worth having an extra in the boat when the engine won't lower at the ramp because the shell cracked. My '89 48 SPL has been a good engine except for the annoying tilt assist.

 

[imported_lorin]

Re: Manual Trim Unit - 48 Special

Yes it is a strong and reliable engine-same block as the 40, 45, 50, and 55. And the tilt assist, when it's working properly is really great. When you think of it, the gas charge takes the place of an electric tilt/trim motor, in that it is used to move the hydraulic fluid around. They just need to spend a few more dollars on the hardware to make it more reliable.

 

[Mostpts@msn.com]

Re: Manual Trim Unit - 48 Special

FYI,if you didnt know,there are a few companies that make units ,nice and light ,it mounts to your boat,motor to it and gives you complete trim and tilt.the boat will perfprm better ,ease of lifting and well built. I think CDC,I have put them on customers that wanted tnt .

Can you provide any company names that supply the tilt and trim referenced in your reply above? My tilt/trim unit on my 96 48 SPL will not raise and the dealer recommends replacing the unit. I have had other problems with the tilt/trim and would like to eliminate it. My e-mail address is mostpts@msn.

Thanks,

Earl

 

[judgejamie]

Re: Manual Trim Unit - 48 Special

i have either a 96 or 94 and my motor is locked in the down position. Can someone give me a link to parts or what I need to do to remedy the situation.

Thanks,
James