Help Tensioning Pop Top Springs

[Ryan89]

A little info on my Van

1989 Ford Econoline E250 Extended Body - Sportsmobile Conversion from Factory.

Manual Pop Top - with no helper springs

From reading the forums and advice from Boywonder I have managed to straighten my bent bars, sleeve with chromoly and replace the bolts with shoulder bolts

Now I am trying to set the spring tension.

My plan is to add 53lbs of solar to the roof in addition to my roof rack witch is currently installed (~60lbs) and have the ability to add another 20lbs of gear to the racks while being able to use the pop top.

Last night i used 70lbs of weight on the roofrack to simulate these conditions and dial in the spring tension.

I have tensioned the main springs by five links and currently with the weight on the roof it takes 90-100lbs of force to pull the roof down, which i think is about right.
The top sits up level and in a good position even with the weight on top.

But it takes 240lbs of force to lift the roof the first 6 inches, then tapers off as it gets higher.

I think this is too much and is almost back breaking especially given the positioning to lift the top.

Were planning on travelling long term in this so I need a solution for everyday use.

My main questions are

1. Can I safely tension the main springs by 5 links or more? Most I have seen on forum has been 4 links and I dont want to damage the mechanism.

2. Has anyone retrofitted the helper springs and the coverplates to an older van that didnt come with them? If so any specs of the springs and photos of the cover plate setup would be appreciated!

[boywonder]

Originally Posted by Ryan89

Manual Pop Top - with no helper springs

But it takes 240lbs of force to lift the roof the first 6 inches, then tapers off as it gets higher.

My main questions are

1. Can I safely tension the main springs by 5 links or more? Most I have seen on forum has been 4 links and I dont want to damage the mechanism.

2. Has anyone retrofitted the helper springs and the coverplates to an older van that didnt come with them? If so any specs of the springs and photos of the cover plate setup would be appreciated!

The helper springs help for those first few inches of up/down travel for the roof. Unforch the geometry of the scissor type mech means that the horizontal springs don't apply much usable force when the top is fully down.

There is lots of info here on the helper springs:

https://www.sportsmobileforum.com/fo...ed-5080-7.html

Post a few pics of the area in the channel behind the crossbars....where the helper springs sit in the newer vans. If It's the same, there's no reason why you can't put helper springs in there.

You need the cover plates to retain the springs in there when they are compressed. Otherwise they can sproing out at very high speed and injure/kill someone or blow a hole through your canvas. The cover plates also provide the end stop for the helper springs so they are not acting on the very end of the channel.

Have you seen my thread on replacing the helper springs with gas struts?

https://www.sportsmobileforum.com/fo...gs-1084-7.html

I've been running this setup for years, much better than the helper springs, although I've had to replace a few struts over the years due to gas/oil leakage, but McMaster has been happily giving me free replacements.

Since you have sleeved your crossbars you can take up more links in the extension springs, however at some point the roof will shoot up fast after the first few inches and you be hanging with all your weight from the handles to try to get it down. With 5 links you may be close to that already.

[larrie]

When we had our 89 RB SMB I used a ratcheting load/cargo bar as a jack to raise the roof up the first few inches.