Assessing the convertible top issues

Hi-Step'n370Z · 10-30-2018, 06:22 AM

Quote:

Originally Posted by gbhrps

Hi-Step'n370Z,

From years of working on all kinds of cars, many of them convertibles, I personally think that little use of the top mechanism, and a lot of use, are the cause of many top opening/closing problems.

In the little use department, hydraulic rams tend to stick in their parked location over time and resist moving when next activated. Ram hydraulic seals tend to harden over time, then eventually leak, particularly when the top is stored over lengthy periods. Electrical wiring for the various sail switches on the rams tend to take a set (like the wrinkles in the top cloth) when stored for lengthy periods, and then break/crack as the wiring ages with the years and hot /cold climate changes. The ram rods , with lack of use, tend to develop surface rust in humid climates and score the seals leading to hydraulic leaks.

In the frequently used department, the wiring frays and breaks from the constant flexing at the fold joints of the top. The rams eventually wear their seals resulting in leaks, and the bungee cords lose their elasticity and don't pull the various top bows out of the way while folding. Hinge joints wear, develop slop and tend to jam, stressing materials, wiring and the top motor and pump.

The tops of 370z's are very intricate, unlike the top mechanisms of convertibles from the 1930's up to the 1980's. Those older cars were either opened and closed by hand, or one hydraulic pump and ram opened and closed the entire top. A failure of those systems were easy to track down and repair. Not so, the top systems of our chosen ride.

I believe that those who use the top mechanism a lot (and I mean a LOT) and those who use it very little (two or three times a year) will have the most top issues.

The best scenario for not having a top issue is to lease this roadster new, and trade for another one before the warranty times out.

For those of us who are into the Roadster for the long haul (my last Z I traded for this present one after 27 years of ownership), I suggest that cycling the top, say once every two weeks at least, is the way to go to prevent the issues of lack of use, for those who seldom put the top up.

For those who have the top up and down frequently I suggest setting aside some money every month towards future repairs, and for those who are mechanically inclined, getting the factory service manual, and educating yourself in the top mechanicals, as many minor issues can be traced down and corrected in your home garage if you understand the system (Bungee cords, frayed/broken wires/leaking hydraulics/etc).

Personally, the only top issue I've had is the 5th bow bungee cord not doing its job, but with some readjusting the bungee, and some helping of the movement of the 5th bow by hand(while outside the car, using the door unlock switch button to lower the top) the problem seldom appears with any regularity.

Gene

Excellent Post Gene. I agree completely with your assessments and advice, and thank you for posting them to the Forum.

I bought my 2010 Roadster more for the look than for the desire to have a convertible, and it soon became a split between a pleasure driver and a show car.

In regard to the top, I don't operate the top often because of the obvious sensitivity to it's components, and also to avoid getting creases.

I had the 5th bow bungee - deck lid hitting issue, and after having new bungee's installed, I put the Z away for the winter. When I took it out of storage in the spring, I operated the top and it lightly hit the deck. I closed it and opened it again and it did not hit.

That got me to thinking that there was something involving the hydraulics, something was "losing it's prime", so I started to I make sure that I cycled the top every four weeks, and once on the day I put in in storage, to see if doing so would keep the bow from hitting the deck, and it did.

I have had no problems since I started doing the monthly maintenance, and pre-storage, cycling.

Also, I have no creases in the top. The top is still flawless and looks brand new, and there are no other signs of anything within the total top system not functioning well.

After reading your recommendations, you suggest cycling every two weeks, and I've been cycling every four weeks.

I picked every four weeks based on a "guess-timate" as a starting point to see if it stopped the deck hitting, and or to work to find the correct cycle interval to do so, and also to keep the cycling to a minimum regarding creases forming on the canvas top.

Understanding and agreeing about the need of a minimal cycling schedule to avoid the various lack of use issues, especially in regard to seals and lubrication - keeping everything coated with oil - the great question now is; is every four weeks enough for the long haul, or would cycling every two weeks turn out to be the better choice?

The only other example I can give that's close to this issue is in regard to the dishwasher in my kitchen. I never use it, but do run a short rinse cycle once a month to avoid the seals drying up. So far, as far as I can tell anyway, it seems to be working.

To me, less friction involved by cycling that causes rub-through on the top, and the other potential wear problems, and to operate the top less frequently to avoid creases, and cycle enough to keep the operating system healthy, is my main goal.

Achieving those goals is quite a balancing act, and we have worked down to a two week differential.

That's pretty good!

Again, thanks for posting such informative and valuable information.

gbhrps · 10-30-2018, 08:33 PM

Hi-Step'n370Z,

Thank you for the compliment ... but I'm not an expert. But I am a backyard mechanic who has been in the backyard for quite a while, some 55 years or so, and I've learned a few things.

I threw the every two weeks timeline for exercising the top out there as a suggestion. You prefer once a month, which is pretty much in the same ballpark, and I would think that either schedule makes perfect sense. I do believe that we are on the right track for ensuring the longevity of our convertible tops' proper function by doing so.

I might also suggest that once a year or so that the hinge points of the top mechanism be lubricated. Small amounts of WD40 or white grease (dielectric silicone grease, comes in a squeeze tube and used on car battery terminals to prevent corrosion) should be applied to all the pivot joints with a small water colour brush (gets into the small areas without over greasing/lubing that could cause stains on the inner and outer top materials).

Stop the opening/closing of the top where the roof is partially folded and the tonneau cover is fully opened. This allows one to get to each of the pivot joints for lubing. Also rub that same silicone grease into all of the top weatherstripping, that on the doors, the trunk, the top storage lid rubber bumper rests, and the hood weatherstripping and rubber bumper stays.

Doing so keeps those parts supple, stops squeaks, and keeps them from freezing to the glass and metal body of those who drive their cars in the winter.

Gene

10-30-2018, 08:33 PM	#2 (permalink)
gbhrps Base Member Join Date: Sep 2016 Location: Ontario, Canada Posts: 213 Drives: 2016 RDSTR TS 6spd Rep Power: 7997	Hi-Step'n370Z, Thank you for the compliment ... but I'm not an expert. But I am a backyard mechanic who has been in the backyard for quite a while, some 55 years or so, and I've learned a few things. I threw the every two weeks timeline for exercising the top out there as a suggestion. You prefer once a month, which is pretty much in the same ballpark, and I would think that either schedule makes perfect sense. I do believe that we are on the right track for ensuring the longevity of our convertible tops' proper function by doing so. I might also suggest that once a year or so that the hinge points of the top mechanism be lubricated. Small amounts of WD40 or white grease (dielectric silicone grease, comes in a squeeze tube and used on car battery terminals to prevent corrosion) should be applied to all the pivot joints with a small water colour brush (gets into the small areas without over greasing/lubing that could cause stains on the inner and outer top materials). Stop the opening/closing of the top where the roof is partially folded and the tonneau cover is fully opened. This allows one to get to each of the pivot joints for lubing. Also rub that same silicone grease into all of the top weatherstripping, that on the doors, the trunk, the top storage lid rubber bumper rests, and the hood weatherstripping and rubber bumper stays. Doing so keeps those parts supple, stops squeaks, and keeps them from freezing to the glass and metal body of those who drive their cars in the winter. Gene Jim S, bunk and mmmm like this.

Similar Threads
Thread	Thread Starter	Forum	Replies	Last Post
First Convertible	eds370zcolo	New 370Z Owner	2	10-16-2011 11:23 AM
Anyone looking for a convertible?	Mt Tam I am	Nissan 370Z Pricing / Ordering Discussions	3	08-19-2010 10:11 AM
Convertible Top Tip	Hi-Step'n370Z	Exterior & Interior	0	04-20-2010 05:28 PM
thinking of buying 370z, then GTM turbo's , but overheat issues,oil issues ??	Christopher	Nissan 370Z General Discussions	19	10-16-2009 03:55 PM
Initial Z issues that are now non-issues......	cave vulture	Nissan 370Z General Discussions	1	09-06-2009 10:19 PM