Convertible top latch hydraulic problem
I would say that the roof micro switches in the ram are working. That switch sends the signal to tell the latch to work and it is clear that the latch is working when it closes. Just doing it early. I would suggest looking at your fluid level first and check the petcock completely closed. If all of that is good then use a dry lube on the joints of the roof and be sure that they are clear of all debris. When spraying the joints protect the area from over spray. When you reset the system did you do it when the roof system was in a normal or abnormal status? I like to reset when the roof is open and the latch is closed.
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Joined: Feb 2011
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From: Arizona
That's probably a stuck latch 'ready to lock' microswitch (item 6 page 6 in the attached)
This is in series with the lift ram 'top raised' microswitch. Both need to be closed before the latch will move to the closed position.
If you download JTIS you'll get the wire colour codes and BPM pinouts to test this, or simply pull off all the trim to get to the latch switches.
You MIGHT get away with the following
Open the pump petcock
Use the Allen Key to open the latch
The top should pop into closed position
Use the Allen key to close the latch
Close the petcock
Then use the switch to open the top.
Lubricate the lock mechanism, open the petcock and cycle the latch many times with the Allen key
Close the petcock and pray while closing the top.
This is in series with the lift ram 'top raised' microswitch. Both need to be closed before the latch will move to the closed position.
If you download JTIS you'll get the wire colour codes and BPM pinouts to test this, or simply pull off all the trim to get to the latch switches.
You MIGHT get away with the following
Open the pump petcock
Use the Allen Key to open the latch
The top should pop into closed position
Use the Allen key to close the latch
Close the petcock
Then use the switch to open the top.
Lubricate the lock mechanism, open the petcock and cycle the latch many times with the Allen key
Close the petcock and pray while closing the top.
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From: Limousin, France
Kymentor,
If you manually retract the latch can you get someone to lean on the top while you lock it.
There's a fair chance that, once properly closed, the BPM will get its act together.
Last edited by steveinfrance; Mar 26, 2013 at 08:21 AM.
Senior Member
Joined: Feb 2011
Posts: 149
Likes: 10
From: Arizona
I would say that the roof micro switches in the ram are working. That switch sends the signal to tell the latch to work and it is clear that the latch is working when it closes. Just doing it early. I would suggest looking at your fluid level first and check the petcock completely closed. If all of that is good then use a dry lube on the joints of the roof and be sure that they are clear of all debris. When spraying the joints protect the area from over spray. When you reset the system did you do it when the roof system was in a normal or abnormal status? I like to reset when the roof is open and the latch is closed.
Just repeating what Walt told me when he designed the valve.
Gus, mine's wired exactly as yours. If I back off the set screw the lift rams stop half way up.
Kymentor,
If you manually retract the latch can you get someone to lean on the top while you lock it.
There's a fair chance that, once properly closed, the BPM will get its act together.
Kymentor,
If you manually retract the latch can you get someone to lean on the top while you lock it.
There's a fair chance that, once properly closed, the BPM will get its act together.
Check your PM
Hi Gus - the fluid level is right up to the line and I have turned the petcock a few times from stop to stop. I did use some dry carbon on the latch ( even though when I installed it it was very smooth as it had been rebuilt by top hydraulics). I reset the system ( touched the battery terminals for 20 secs) when in abnormal mode to get any residuals to discharge.
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From: Limousin, France
All I can say is that's how I set the working pressure on mine. It came preset to whatever it should be but I was able to back it off even more until the top just moved normally with no hesitation.
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From: New Jersey
I think it's this way.
In the neighborhood that the LSI valve is normally set, ~ 1000 PSI, it does not come into play as the top is being raised or lowered, because the pressure then is ~ 800 PSI or less (that number from memory, but it's for sure well under 1000 PSI).
That's probably what was meant by "the rams don't see it". But it is in the circuit all the time, so if it's set to a low enough pressure limit then the rams will see it.
In the neighborhood that the LSI valve is normally set, ~ 1000 PSI, it does not come into play as the top is being raised or lowered, because the pressure then is ~ 800 PSI or less (that number from memory, but it's for sure well under 1000 PSI).
That's probably what was meant by "the rams don't see it". But it is in the circuit all the time, so if it's set to a low enough pressure limit then the rams will see it.
It was suggested by Walt that port that the PRV was installed was for the latch and not the lifts. The pump has two distinctive functions operating two valves and two ports and they do not interfere with each other. I have a pump that I will check this to verify but I have not reason to doubt Walt.
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From: New Jersey
This much I can say from 1st hand experience. The port on the pump body where the valve is attached ... that port sees the pressure that the pump is making, no matter whether it is directed to rams or latch or both, no matter whether the pump is running in one direction or the other.
The PRV see the pressure to the rams as well so I stand to be corrected. However, adjusting it takes it out of the factory settings and that will affect the pressure to the latch as well. The extreme is that you could cancel all the good the valve was designed to do.
The rams are going to complete extension and we are seeing this because the latch system is activated by the ram switch so adjusting the PRV is not a fix for this but timing is. In fact we are seeing the latch close without grabbing the roof.
The rams are going to complete extension and we are seeing this because the latch system is activated by the ram switch so adjusting the PRV is not a fix for this but timing is. In fact we are seeing the latch close without grabbing the roof.
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From: Limousin, France
He has two problems
1. A slow moving top which could be low pressure from the PRV.
2. As you say, Gus, mis-timing of the latch mechanism.
In my opinion that is due to a permanently closed ready to latch switch.
As soon as the lift ram gets near to the end of travel and actuates the top up switch (in series with the RTL switch) the BPM thinks the claw's in the latch and closes it.
1. A slow moving top which could be low pressure from the PRV.
2. As you say, Gus, mis-timing of the latch mechanism.
In my opinion that is due to a permanently closed ready to latch switch.
As soon as the lift ram gets near to the end of travel and actuates the top up switch (in series with the RTL switch) the BPM thinks the claw's in the latch and closes it.
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From: Limousin, France
Gus, you know much more about this than I do but the latch CANNOT operate until the 'Ready to Latch' microswitch closes.
This can only close when the hook on the top pushes on the latch claw and actuates the switch.
It isn't a timing thing, the BPM needs to see both 'Top Raised' and 'Ready to Latch' before actuating the latch mechanism.
This can only close when the hook on the top pushes on the latch claw and actuates the switch.
It isn't a timing thing, the BPM needs to see both 'Top Raised' and 'Ready to Latch' before actuating the latch mechanism.