I personally think the price for the relief valve is well worth the peace of mind you get for lowering the pressure and extending the life of your hoses, particularly when you consider the amount of work involved in replacing them.

 

No problem and, in the end, I sure we all really love and enjoy each other's company here. It is just my opinion that "big business" and "corporations" get enough lumps without the need to beat up on them here.


Doug

 

Thanks for dragging me into this Doug

The statement above is correct for a brick and mortar firm, but you grossly underestimate the cost of even a one-man home operation if you try to do things right, legally, and make a quality product. I have invested several thousand dollars in the remote top module. If things work out, I may make my money back and earn a small profit in a few months...it remains to be seen.

What you are missing is the risk and cost of making quantity buys to keeps prices reasonable, buying equipment to make even modest production somewhat efficient, ESD control, tooling cost for printed circuit boards, costs for customized wiring, company startup and licensing costs (I formed an LLC), website costs, protoyping costs, taxes (I have to pay them too), advertising and more. Not to mention the hundreds of hours my wife and I put into this between design, testing and production.

 

I didn't mean anything in a bad way but did not want to leave out your contributions as one of those guys who have taken it upon themselves to develop something really useful and make it available to the rest of us here

Doug

 

FWIW, my take-aways from today's goings on:

- After more than a year of voltage reduction systems working in the field, we have the first report of the system causing a stall while raising the convertible top. The circumstances are somewhat remarkable, but the report should be taken at face value. If anyone else has seen this, please let us know. Any fair-minded person should want to know how the system really behaves. Why would anyone not want to report it if that's what they saw?

- Several emails and PMs today from serious folks really wanting to drill down and understand how this system works. More to come on that in a new thread.

- Sincere thanks to Rev. Sam for his spirited defense of this whole project.

Anyway, that's how it looks from here.

 

Jeesh, here we go again, back on this merry go round!

For the last time, everyone needs to understand that we all have differing ideas / opinions on just about everything. If we can drill down to that basic fact and agree that one likes this system whilst another likes that system, I'm sure it'll all blow over and we can get on.

Obviously there are those that have bought system A and will praise it / defend it to the hilt and recommend to tohers as that is human nature.
Similarly those thta support option B will chime in and do the same.

All that's fine, but thats where it must end for the harmony of the forum!

What I find particularly crazy, is that although some of us have a serious difference of opinion, we are all trying to work towards the same end goal.....surely we should try and remember that?

This is without doubt the bigest single cause of disharmony on this site and will come to a close one way or another.

 

Jim, thanks for throwing some cold water on this. I have completely resigned form this forum because certain individuals are abusive and continue to make statements that have no substance. These so called engineers are an embarrassment to my profession. If they are offended by these comments, good, because I am really offended by theirs.

I took a big risk when I directed my company to supply pressure relief valve kits. I did this from a desire to help people out. I have unique experience from working with some large hydraulic equipment manufacturers and have designed many hydraulic control systems.

The post in this thread about the cost of the parts in our kit is completely wrong. We buy the kit from a sub-contractor who is professionally equipped to make the hoses with proper tooling. Everything about it is of the highest quality. The valve is factory calibrated to our specifications. We assume full responsibility for the product and I personally spend a lot of time consulting with owners and mechanics as they try to sort out their problems. To say that we are ripping people off is a complete lie, I am really offended by it, and I have zero respect for the people who make these comments. Once upon a time there were friendly people on this forum but that is no more due to certain individuals.

Regarding the "resistor solution" I will reiterate what I said way back when this all started on another forum. Prove your point. You have never supplied one wit of data that confirms that the voltage reduction approach does anything but slow the roof down. The real problem here is what happens when everything stops moving and the controller keeps the pump turning with zero flow. Get a pressure transducer, hook it up, and publish the data. This will bring an end to a discussion that is currently based on BS.

Regarding systems that may have failed after a relief valve (or resistor) was installed, we have no idea what shape things were in when the work was done. Regardless of how things are done there is still significant pressure in the system and these things don't last forever. The hoses were likely in some stage of decay and none of the above has remedial properties. I advise every one I speak with to inspect the hoses first because that is the top priority and where their first money should go. The goal is to get reasonable service life from the roof system, but nothing lasts forever.

Goodby forever.

 

Congrats, you've offended me. Glad you're happy.

Just because someone else has a different view, it's nice to know that I'm not a nice person. Actually, I'm kind of an a**hole and I don't mean to troll, but grow some thicker skin and grow up a little. You're acting like a child.

/sarcasm

 

Xeno,

That post you were referring to ... I'l never know how that ended if you know what I mean. Anyway, I'm sure he wanted to offend me rather than you, so sorry for any of the mud that got on you.

 

You guys are unbelievable.

Jim sent out a warning message in post 46 above, that this will come to a close one way or another.

Yet still you continue to make things personal, with petty school yard jibes and digs.

There are two proposed assistance type solutions to an expensive and for some people more annoyingly a messy problem.

Neither solution claims to be 100% effective.

Both solutions rely on the condition of the system prior to their implementation.

One solution is mechanical.

One solution is electrical.

Is one solution better than the other, I have no idea?

This could only be ascertained by back to back testing over a long period with controlled conditions.

The price for either solution is irrelevant, you pays your money and you takes your choice.

As stated repeatedly through posts about these solutions, neither will solve or cure an existing problem, at best they will only postpone the day when a hose change is required.

If then you find that the solution you bought does not do what the seller said it would do then, you take it up with them.

If there are any more digs of a personal nature from ANYONE in regards to these solutions, expect to be removed from the forum.

I am leaving the various threads open for now, because despite everything else there could be some good technical discussion and or questions from people either using, or considering using one of these solutions.

This really is the final chance.
Keep it technical, and we're good.

 

I don't in any way intend to stir the pot but it is a real loss if escalating rowdiness results in long-time valuable members like Walt find it difficult to remain members.

Doug

 

No worries. I probably shouldn't have responded but I get a bit irritated when I see people making blanket generalizations especially when they're false and include me.

This is an amazing forum. Forums contain people. Some people will never get along. This is the internet and if you're letting someone get to you, that's an issue that you need to deal with.

 

+1

 

As a newer Member I am somewhat perplexed about the problem of hydraulic hose bursting.It would seem to me that the problem is ; that the hoses used by Jaguar do not meet the max.PSI specs required for proper operation.

I have an aircraft which has a hydraulic system to operate the landing gear
up/down cycles. I have gauges on both up and down cycles and during hot weather, it is not uncmmon to see pressures in excess of 3000 psi.in the up cycle
I use 3/8" id hydraulic hose( available from many suppliers) with a max operating pressure limit of 4000 psi and have never had any problems with the hoses.

Something to think about ?

 

Airplane parts are quite a bit different than car parts. That hose might be rated for 4000 psi, but the burst pressure is probably 4 or 5 times the max operating pressure.

 

I started this thread. I must not, as they say, "have a clue." For the most part I didn't know there was a undercurrent going on between contrubuters. In the mean time I learned a lot. In this reply I had intended to talk about thightly coupled hydraulic pumps and loosley coupled pumps, and systems that evedently will fail at pressures as low as 1000 psi, but I'm not. For those of us who delve into this sort of information, we now know the difference between the two modifications. The resistor design is not the tight engineering design that an engineering boss might expect, but it is just a car, and it will provide some protection. I actually thought it was a good example of thinking "outside the box." I have really enjoyed see bright people work through this. Thanks everyone. Please don't stop contributing, we need you.

 

Thanks Martin for returning here here on this and also for your final words........

"Thanks everyone. Please don't stop contributing, we need you. "

On that note, this particular thread is closed!