Thanks. I confess to knowing nothing about how the valving is done. I guess I'd summarize my reasons for believing it has to be "valve always open, switched directions" rather than "valve open/closed" this way:

- I can't see another way to interpret the documentation, pg. 2

- if Off means closed, then there can't be times where latch or main valve is Off, but the latch or main rams are being moved. That seems to conflict with the opening and closing sequences, pgs. 5 and 6. (There is no conflict if Off means "permit flow to compress rams".)

- The reservoir has to be switched from one side to the other. I can't see any way that gets done if the valves are just doing Open/Closed.

I guess at this point it's just academic. Still fun though.

edit: Come to think, for me it is not academic. To do the conversion to manual latch (remember that?) I need to replace the latch hose circuit with some sort of dummy. What can work there depends on what the real meanings of "On" and "Off" are for these valves.

 

edit: Come to think, for me it is not academic. To do the conversion to manual latch (remember that?) I need to replace the latch hose circuit with some sort of dummy. What can work there depends on what the real meanings of "On" and "Off" are for these valves.
Yes, I'm afraid that's what I've been binding on about.
If pressure is applied to latch and lift simultaneously (which your earlier post convinces me is true) then you must cap off the latch outputs.
If the pressure is magically switched between lift and latch then you need to jumper them to avoid overloading the pump.
In my case that wouldn't matter since the relief valve would blow off excess pressure but you might stall the pump.
(debates about valve vs resistor carry the death penalty here BTW).

 

Thanks. I would be worried about my conclusions if you saw this otherwise. I think I see a middle ground:

These have problems ...
- Capping the latch ports: guarantees we don't bleed off the pressure needed to raise/lower the top, but we risk dead heads when the pump thinks its operating the latch. (This option is OK with relief valve in place.)
- A wide-open shunt between the latch ports: no dead heads but prevents the pump from making enough pressure to raise/lower the top.

So ...
How about a dummy hose circuit between the latch ports with some sort of orifice/restrictor in it. Allow some tiny amount of flow so we don't ever get a dead head, but not so much as to knock down the pressure needed to raise/lower the top. We started to touch on this idea a few posts back, circa post #23. (I don't know how to size the orifice; any help much appreciated.)

I plan to use capping for initial testing and, yes, I'll have to be careful. There's a re*i*s**r on my pump, whick makes this less scary (to me anyway). But no matter what, it's gonna need to get more then a little warmer here before we run this to ground.

 

Because the caps are so cheap I'd just bung them on as you say.
I'd guess you'll know in a few seconds if it's a Bad Idea because you'll hear the pump labour and your Rotsiser will get hot.

 

What are your thoughts on Lanny's arrangement where his latch ports are open and apparently nothing comes out?

 

Good job someone can read.
I must be wrong then, the solenoid really does turn the flow on and off.
That would be the sensible thing to do - disconnect the supply to the latch solenoid, crack open the pipe unions and see if anything comes out.

 

Lanny's ports are capped, not open. If they were open we would have a biblical scale green shower.

 

Dennis - does he say that ? Is it somewhere in the other v. long thread ?

 

Steve,

Yeah, I'm sure I recall it being mentioned, but couldn't say exactly what post.

Maybe Lanny will chime in and confirm. (This carries a certain risk for me; if the ports are open, my head will explode.)

 

Agree re head explosion - I can't make it work.
I'll pm Lanny - meanwhile apply a tight, wet elasticated bandage to the forehead.

 

Here it is, from post #8 I'm pretty sure that he says the same thing in his other thread.

 

I can't find what I thought I remembered reading.

If both latch ports on Lanny's pump are in fact wide open (it seems possible for one to be open, the one opposed by the setting of the disconnected? latch solenoid) and it does not expell fluid when the pump runs in either direction, then I'm hopelessly confused.

I hope Lanny will see this and tell us, doing a close look to see the condition of both of the pump's latch ports.

 

He's toddled off to look closely at the pump so expect a reply soon.

 

I understand all that. Of the whole system, there is one hose that is more likely to fail than any of the other components, and I believe that it was the factory installation process that was primarily responsible. The two failed hoses that I have seen appear to have had torsion twists at the same break point... the plastic coating gets brittle and the torsion helps to crack and separate the hose until it fails. I replaced those.

I know the lift ram seals and top latch are also prone to failure, but they're far less likely to fail. If that happens, I'll deal with it when it does.

Good luck, but to me this is not a viable option.

The only reason I would consider this is for weight savings.

 

Hi Guys,
boy I sure don't want to be responsible for anyone,s head exploding. I rechecked my pump, and there are definitely not caps on the outlets. Is it possible that it is blocked internally somehow.However, I don't see anything to support this. [IMG]i:dsc06971.jpg[/IMG] I hope this picture gets through. ( I am not sure how to include a picture for sure)
It is my opinion that one of the two solenoids is what decides when, and if ,the fluid goes to the latch. I believe that solenoid is disabled on my car. As I have said before, the top goes up and down just fine. My rear windows are controlled by a separate DPDT switch. The only problem is the "top not latched" message that won't go away, even if the top is retracted.
If this picture does not come through maybe someone can explain how to do it right. I have several pic's I can post. Stay strong my friends.......

 

Déjà vu!

 

I agree with that! Prior to replacing my hoses with the Coliflower S/S lines I insalled the pressure reduction valve. After replacing the lines I had the top latch rebuilt with new, heavy duty seals. Then I went ahead and installed the Remote Top from WhiteXKR.

The price for all this bulletproofing was about $1,000 but now I use the top without fear whenever I want; the top goes up and down more often than a spring break girl's on Bourbon street...

 

I looked brefly at purchasing a 2000's era Mercedes SL500. If you want to see a REALLY complex system check out the hard top convertable set up they have...

Their forum is filled with unhappy owners and expensive repairs...

 

[IMG]jag pump.jpg[/IMG] All right! that is a little more helpful I think.
[IMG]jag pump2.jpg[/IMG]

 

Yup, we see them. Those ports sure look plugged to me which, if so, defers my head explosion. (After last night, it might be better if it did. Ouch!)

I did a quick test on my car and found that if I loosen the latch hoses at the pump, even with latch valve off, fluid gets pushed out. This is the only behavior, IMO, that makes sense given what the 501-11 doc tells us about the valves.

Not for Lanny, but a super-bowl inspired thought for the day: before beginning an end-zone dance, be sure which end-zone the ball is in.