TNT Question....Anybody?

[OBJ]

Rebuilt the cylinders on my 84' 50hp Johnny. This is the unit with the lift bracket bolted to the swivel bracket and has the three wire pump.<br /><br />While I had the unit on the bench, I filled an bled off the system until reservoir level was even with the fill hole. Reinstalled unit back on engine.<br /><br />Ran engine up and down a couple times and all seemed well. Left the engine tilted all the up. Came back a short time later and noticed the engine had lowered. In the water, when trimed out, throttleing up will push the engine back in against the stop.<br /><br />This did not bode well with my ego so I took the unit back off. Back on the bench, I noticed that when the cylinders are in the full extended postition, I can push down on the trim cylinder almost all the way....never noticed this before.<br /><br />Question is, should this happen or is this natural since this is the trim cylinder or did I (perish the thought) screw up? Maybe didn't get a good bleed on the unit?<br /><br />Thanks for any help<br /><br />Jim

 

[OBJ]

Re: TNT Question....Anybody?

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[OBJ]

Re: TNT Question....Anybody?

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[OBJ]

Re: TNT Question....Anybody?

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[ob]

Re: TNT Question....Anybody?

Well ,I'll ask a few stupid questions and then leave this one to the pros.Did you insure the reservoir was topped off in the full up position(on boat) after you ran it up and down a few times?If this unit has a manual release screw,is it seated?Otherwise ,whatever you replaced in rebuilding the cylinders ,will maybe need disassembly and a second look.<br /><br />Is the current symptom the reason for the initial overhaul or was it not working at all?

 

[OBJ]

Re: TNT Question....Anybody?

Yep...cylinders full extended when reservoir was checked. Cycled 4 times check...top off...cycle....you get the picture. Yes this was the original reason. When I first put it back on the engine....it held.<br /><br />I used very thin shim stock to reassemble the cylinders. Been scratch'n more than my head on this one.<br /><br />Hey....thanks ob.....maybe yer right...maybe ought to recheck the work. Might try Joe Reeves idea of putting air pressure on the system....see if that cures it.

 

[ob]

Re: TNT Question....Anybody?

Hope you're able to get her nailed down OBJ.Sorry I couldn't be of more technical assistance on this one.Fact is ,I've never had to tear into one of my own yet.Knock on wood.

 

[OBJ]

Re: TNT Question....Anybody?

Hey....moral support is always appreciated ob....

 

[ob]

Re: TNT Question....Anybody?

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[OBJ]

Re: TNT Question....Anybody?

No update cause I ain't got to it yet. Read a little and am thinking I'd like to check the check valve but not real sure how to get to it. It's behind a plug and I'm not sure how to get it out.....nut's.

 

[ob]

Re: TNT Question....Anybody?

I'll be lurking around.Sorta interested on what you find.I may be there some day myself.

 

[MarkV_Deep6]

Re: TNT Question....Anybody?

Have you replaced all the internal soft goods and o-rings? There are a couple under the pump side that can be quite difficult to pull. I'm assuming you have verified the manual bleed down valve is in good condition.

 

[OBJ]

Re: TNT Question....Anybody?

That's what I'm mulling over MarkIV...how to get to them. I know there in there and I know they got orings...but not quite sure how to pull the plugs to get to them. My luck...I'd pull the plugs and end up with a piece of junk on my hands. I'm hoping someone will come a long and tell me how.

 

[OBJ]

Re: TNT Question....Anybody?

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[rodbolt]

Re: TNT Question....Anybody?

your going to have to have the factory service manual and the correct test guages.<br /> it could be a simple as a bad/dirty manual relese valve, a bad seal in the tilt or trim ram to a defective main valve.<br /> I have not had on of the 2cyl 3 ram systems open in years.<br /> ill look about for some of my notes.<br />is this the 3 ram setup with the motor mounted outside the bracket ?

 

[OBJ]

Re: TNT Question....Anybody?

It's a two ram set up Tom. With the lift bracket bolted to the swivel bracket. Motor sets on the outside. Just rebuilt both ram cylinders and took the pump apart and cleaned it also. The only part I didn't get out was the check valve because I was afraid of removing the plug over it. So I took a chance.....<br /><br />I got the OEM manual (OMC) for the unit but it doesn't tell how to remove or replace the check valve. It's an 84' unit.

 

[MarkV_Deep6]

Re: TNT Question....Anybody?

It's not easy to get those orings out.. and that is where I found my problem like yours was orriginating. The little cylinders inside with the orings have a small hole in the side. I made a tool from wire that would allow me to pull them out. There is also a small seat on the bottom of some of them and this area could be worn or have trash traped there. It will take more than one attempt to pry those things out but be patient an d just keep pulling at them. Sorry it took so long to reply.

 

[OBJ]

Re: TNT Question....Anybody?

Thanks Mark for the info. What did you replace the plugs with?

 

[MarkV_Deep6]

Re: TNT Question....Anybody?

If you bought a repair kit, you should just replace the orings and soft goods on those plugs. then just reinstall them. Be careful not to scratch or nick the surface of the metal.<br /><br />This is the beauty of hydraulic parts.. it very rare when a metal piece is damaged and needs to be replaced. I had an aluminum component in one of the units I repaired. It was damaged somehow, I replaced it with one that was brass from the (old) doner unit. Don't know why the mix in materials on that one.