Genoa car moving backwards under load

[keithw88]

Does the car have (or should it have) nylon slider inserts to fit closely around the track inside the bottom part of the car? If this is worn or missing, the car would twist upwards under load; the two metal surfaces would exert quite some friction on each other so maybe the car would rather slowly grind/edge it's way aft....

[Tillsbury]

I agree that these should be fitted plunger backwards. The vertical rollers are to prevent chafe on the sheet depending on how it leads back to the winch. If they’re installed the wrong way round they will tend to jump out.

[LongRange]

Originally Posted by keithw88

Does the car have (or should it have) nylon slider inserts to fit closely around the track inside the bottom part of the car? If this is worn or missing, the car would twist upwards under load; the two metal surfaces would exert quite some friction on each other so maybe the car would rather slowly grind/edge it's way aft....

Thanks, that seems quite possible. I think I will take the cars apart and try to inspect them for worn sliders or pads. Coupled with a too-short plunger design, I can see how that might result in just enough clearance to lift the pin out of the retaining hole.

[LongRange]

Originally Posted by Stu Jackson

Why keep fighting the same issue.


Either buy fixed pin stop cars or the adjustable cars.


Garhauer is a great source.

Yes, a couple of external stops may actually be a more definitive - and cheaper - fix than attempting to find spares for a specific Lewmar part which is by now a rarity. Thanks.

[Suijin]

I personally don't like non-articulating lead cars. I would do yourself a favor and replace them with something better, that does not exert torquing force on the car foot slide (which incidentally makes them a b*$&h to move under any load, as well). Garhaur has good quality at reasonable prices.

The fact that this genoa car design disappeared fairly quickly should tell you something. It's just not very good.

And yes, IMHO the pin should be at the rear, which is forced down onto the track under load instead of lifted, as well as being more easily accessible for moving the car. The reverse strikes me as poor design although I'm sure Lewmar had some reason for it.

[LongRange]

Regarding direction, I am reasonably confident that these stirrup-type cars are meant to be mounted plunger-forward, the way they are on the boat now.

Lacking side-to-side articulation, it is the vertical rollers that are meant to compensate for lateral loads from the sheet. If those vertical rollers faced backwards, they would be mostly useless, since the path from the car back to the footblock is straight and fixed. Meanwhile, the main car roller would no longer have those vertical rollers in front of it to straighten the sheet angles, leaving the sheet to routinely sit across the side of the main roller instead of inside it.

Also, the whole (fixed) angle of the car seems designed to bisect the ~120 degrees between the sheet and the deck. If the car was turned around so that the plunger was facing backwards, i can see how that would reduce the lifting loads on the plunger, but at the risk of damage or structural failure of the car and or track due to weird angles and uneven loading.

I appreciate the suggestions, thanks.

[LongRange]

Originally Posted by Suijin

I personally don't like non-articulating lead cars. I would do yourself a favor and replace them with something better, that does not exert torquing force on the car foot slide (which incidentally makes them a b*$&h to move under any load, as well). Garhaur has good quality at reasonable prices.

The fact that this genoa car design disappeared fairly quickly should tell you something. It's just not very good.

And yes, IMHO the pin should be at the rear, which is forced down onto the track under load instead of lifted, as well as being more easily accessible for moving the car. The reverse strikes me as poor design although I'm sure Lewmar had some reason for it.

Thanks, I can see the logic in that. The plunger _should_ be at the back, being subjected to less lifting load or even being driven down into the track. However, in the case of this design the plunger is forward, and coupled with the lack of articulation it is not a great design overall.

I will investigate alternatives that fit this track...

[RobertoD]

Very Simple - cars are installed backwards. The pin should be towards the stern, that way the upward force of the genoas sheet lifts the front of the car and pushes down on the pin, keeping it in the hole. The way you have them, the force of the genoa sheet is lifting the pin out of the hole.
They were installed backwards - sometimes happens. I once worked for e boatbuilder where 10 boats were sent out with the fwd running lights reversed!!
Same problem on two similar boats says installer was not too bright - or had a bad night the day before!.

[sand6000]

I would definately use it with the plunger facing aft.

[LongRange]

Thanks.

While I can see how turning these cars around, so the plunger is at the back, would very probably solve the backwards creeping issue, I am very reluctant to do that because of the non-articulating design of the car and those unusual vertical rollers. It seems very important to have those facing toward the genoa.

I think I will try to find a pair of standalone plunger cars that fit this track (they used to make things like that, years ago), and to see whether the sliders can be renewed.

If that gets expensive, I will just replace these cars altogether. I think Suijin is right - the design is fundamentally flawed.

[nigel1]

I have these lewmar cars on my bene 473. The plunger should be forwards, to allow the side rollers to function.
Mine have not shifted under load, although I have replaced all the springs. Spares are still available, or at least they were last year. Contact Lewmar, the spare parts come from Italy.

[rom]

Hi LongRange, everyone,


I have the same problem with my Harken cars. They look pretty much the same as yours. 32mm 6mm T track.


I can see you are in the Med so the US vendor that some have proposed may not suit you. I am considering a Pfeiffer Marine from SVB in Germany. It comes at half the price of the Harken (GT326S).


Of course it would be cheaper if you could just buy some spare parts, springs & sliders, I could not find any for mine.


as to reinstalling the cars backward, oh boy , you don't always get good advice from CF