1991 Force Tilt / Trim

[forcemoser]

Greetings,<br /><br />I have a 1991 Force 70 h.p. with power Tilt / Trim.<br />I can not locate the manual release valve. Can anyone help. <br /><br />Thanks

 

[RRitt]

Re: 1991 Force Tilt / Trim

it's the internal ring clip on end of valve housing. many times they are painted in and it's easier to just block the motor into tilted position and loosen the hydraulic fittings. The two front ones are up and the two back ones are down.<br /><br />however .... if you are a salt water boater then the stainless steel oil tubes have been attacking your aluminum pump valve since 1991 and the fittings might be seized. If they don't unscrew easily then don't force them. It is better to cut the oil lines than to strip the aluminum port threads.

 

[forcemoser]

Re: 1991 Force Tilt / Trim

 

[forcemoser]

Re: 1991 Force Tilt / Trim

 

[forcemoser]

Re: 1991 Force Tilt / Trim

Thanks for the reply. I'm some what new to outboards. When you say " it's the internal ring clip on end of valve housing" do you mean on the bottom of the pump motor or is there something on the TILT/TRIM CYLINDER ASSEMBLY? There is nothing on the side of the pump motor other than the fill plug. What I'm trying to figure out is how to raise the motor if the tilt / trim dies at the lake. I'll need to raise the motor to get my boat onto the trailer and down the road.<br /><br />Thanks

 

[RRitt]

Re: 1991 Force Tilt / Trim

referring to this picture<br /> http://www.mercruiserparts.com/IMAGES/FORCE/823089/63.png <br /><br />at the bottom of part #2 there is a hump that runs down the middle. It where springs and valves and ball beraings and stuff like that go in order to control into which tube the oil gets pumped. All of the "guts" are held in with a ring clip. It should have two little eyes where a specialized tool can grab it and squeeze it together. when you squeeze it, it diameter gets smaller and the clip comes out of its groove. when the clip comes out, the seal is broken and pressure is relieved. unscrewing the brake fittings does the same thing and only requires a 3/8" standard or brake wrench. just be careful not to let any water get into the system. the ball bearings and hydraulic pistons are steel and they can rust.

 

[roscoe]

Re: 1991 Force Tilt / Trim

forcemoser, I believe your unit is different from the one described by RRitt.<br /><br />Yours should only have 2 hydrolic lines.<br />There is no ring clip to remove.<br /><br />There is no manual release on your unit.<br /><br />The only way to release it is to loosen one of the lines, possibly both of them. And then you will have no way of holding the motor in place once you raise it. <br /><br />This applies to all 91-95 70hp models, and some 40 and 50 hp models.<br /><br />I've been thinking about fabricating a release valve for mine, but haven't gotten around to it yet.

 

[RRitt]

Re: 1991 Force Tilt / Trim

roscoe, if the valve body from a four line system fits the pump motor then you could simply plug the two unused ports. I am always on the lookout for broken 4line TnT systems because I remanufacture them and good cores are always in short supply. I have seen broken 4line motors with good valves attached sell for much less than $50. <br /><br />Another approach would be to put a M/M inverted flare union on the valve port, a weatherhead 1441 adapter on the union, a SAE flare tee on that. buy a few feet of CuNi tubing which is corrosion proof and soft enough for flaring and finish the system off with female SAE flare at the tee and male inverted flare at the tilt ram. Then you could put a standard relief valve onto the open Tee. Everything should be in stock at NAPA except the CuNi tubing. The US tradename for CuNi 90/10 is BrakeQuip EziBend. The industrial name is Alloy 70600. Use brass fittings. Research papers on galvanic corrosion in marine systems have specifically identified SS tubing/fitting onto aluminum hydraulics as one of the worst case scenarios due to very bad C/A ratios.

 

[forcemoser]

Re: 1991 Force Tilt / Trim

Roscoe and Rritt, thanks for the help. After examining the bottom the unit, it appears that Roscoe is right. I currently don't have a problem, but I was trying to formulate a plan should things go south while at the lake. At least now I know I will be able to get the boat on the trailer, not sure how I would get the boat home. <br /><br />Thanks again - Tom Moser

 

[roscoe]

Re: 1991 Force Tilt / Trim

RRitt, you know way too much about fittings.

 

[RRitt]

Re: 1991 Force Tilt / Trim

It's because I reman the Chrysler/Force 70HP+ TnT systems for salt water. Stainless absolutely destroys the aluminum in salt water. You have to pour through a half dozen fitting catalogs to come up with just one not-steel fitting. The WH1441 is a fitting to remember. NAPA carries them and you can use it to fix the tilt collar.