Tilt Cylinder question.

[khoonie]

I have a 1988 Force 125 with the original tilt/trim system. I believe it is the prestolite system. My question concerns the tilt cylinder housing. The system began leaking down and when I checked it out I noticed the top of the tilt cylinder housing was pushed up and away from the cylinder on one side and was leaking badly. I took it off and found that the top of the cylinder housing just screwed down into the cylinder like a cap on a threaded pipe. What had happened was that the pressure had pushed so hard on the threaded top or "cap", that it had pushed the threads up on one side and this had caused the leak. I have never seen threads warped out of place like that. Anyway, I took it apart and used a wire brush on the threads and a pick tool to remove all the broken/bent threads, brushed it again and checked to see if it would screw back on with the remaining threads. To my surprise, it screwed back on straight and smooth and seated down on the o-ring properly. My question is: Do you think the re-worked cap threads will hold the cap on, or should I do something else? I have not been able to find a replacement tilt cylinder housing unit anywhere - you have to buy the whole system, which is way beyond my budget at this time. So, I am trying to make this one work. Any ideas on this?

 

[pnwboat]

It's hard to predict if the threads will hold. Only time will tell. If it threaded on OK, then it may hold. The rubber "O" ring is what seals the cylinder. The threads are there to just hold the cap on. Cross your fingers. In the mean time, you can look for a replacement cylinder. I've seen them from time to time.

 

[Jiggz]

I wonder if the cap of the shock absorber is the same and interchangeable with the tilt cylinder? That will at least give you better threads on the cap even though some of the threads on the cylinder itself are a little worn out. If not, I will try using some thread sealants (red) to keep the cap in place until a proper replacement can be found.

 

[khoonie]

Thanks for the advice/ideas. That is a good idea about the shock absorber cylinder cap - I am going to take a close look at that - it might work! I am going to try out the system today and see what happens with the cylinder cap - at least now I have some options if it does not hold. Is the red thread sealant something I can find at automotive or hardware stores? I appreciate the help.

 

[Jiggz]

Yes, it is available at auto stores and even online at *bay. Just make sure you get the one that is resistant to oil and fuel or petroleum products.

 

[Frank Acampora]

The cap of the cylinder is usually under very little pressure because the weight of the engine will actually move the engine down. HOWEVER, once the engine is down all the way, if you continue to hold the switch on, you will cause added pressure AND the fluid (in the pump and reservoir) will foam. The shock absorber is indeed the same as the tilt cylinder: A tapered hole is drilled in the side and the band and hydraulic fitting is set in place. Another hole is drilled in the bottom and tapped for the hydraulic fitting. I never opened one up, but I suspect that the shock has different valving on the piston.

Given the old cylinder as a template, a machine shop could convert a shock to a tilt cylinder quite easily.

 

[khoonie]

Well, that explains what happened to warp the threads. I had previously replaced the momentary switch, which had failed in the night, and had apparently been running for quite a while in the down/tilt position when I discovered it the next morning on a fishing/camping trip. I had to rebuild the motor and replace the switch, but I did not notice the warped cylinder cap. I have tested the affected tilt cylinder and it seems to be holding fine - but now I have a leak-down problem which I suspect is the pump - I do not see any leaks in the system at all, but it is still leaking down - and fairly quickly. Are there any alternatives to replacing the pump? (And to think - all of this was caused because a 4-dollar momentary switch failed...)

 

[Jiggz]

If the leak down is fast, I would first suspect the tilt cylinder. There is another thread about tilt and trim and I posted procedure to test which component is actually causing the leak down. You might want to do that test first to make sure you spend your time and $$$ accordingly.

 

[jerryjerry05]

If it leaks all the way down?
Usually the pump.
My stbd. motor leaks down to the trim and stops there.
I know the cylinder's bad.
Changing it ain't gonna happen any time soon.
It works. Sort of?
Profile? Location? You might be close to someone who can help?
I have some 40-50 hp. trim parts. Lift cylinders and trim cylinders. If anyone wants to trade?

 

[khoonie]

Jiggz, where could I find these brass female caps that you mentioned in the leak down tests? I am going to test my system as you have outlined, but I do not have these caps. JerryJerry05, my engine is a 125 hp, so I guess yours won't work for me, but thanks anyway. I have filled out my profile, though.

 

[Jiggz]

The caps are available at any auto store or Ace hardware. I got mine at Ace although I have seen them also at AutoZone and O-reilly's auto stores.

 

[khoonie]

I found the caps at autozone and I am going to test the system asap. However, I believe I have found a leak in the pump body - I found fluid at the bottom of it. It looks like the fluid is coming out of the seam where the bottom "cap" of the pump body attaches to the cylinder. There are four screws there that tighten the "cap" down and they look rusted and corroded. The seam also looks rusty. So, I suppose I will have to take it apart and see if I have a bad seal or whatever... it might be that the part was not screwed down tight enough or had loosened thru time and if the seal is bad, that could be the problem. I will update this as soon as I have checked it out. Jiggz, should I test the system BEFORE I take the pump body apart? Suggestions? Thanks to everyone for the help.

 

[Jiggz]

You need to fix the leak before conducting the test otherwise it will give you a vague result. The valve body (VB) (were all the tubings connect to) attaches to the pump body or reservoir with 4 screws and is sealed by an O-ring. Nothing in the reservoir and the VB connections is under pressure except for the level of the oil in the reservoir. Check the tightness of the screws first and see if that will stop the leak.

 

[khoonie]

I have not been able to get back to the system test yet - I will post as soon as I can with the results and go from there. Thanks!