Air Suspension for Hymer 680 Starline on Merc 413 chassis Forums

jemshome

Has anyone fitted or had fitted air-suspension on a m/h based upon a Mercedes 413 chassis?

I'm interested in options available, product quality and cost comparisons, rather than the generic benefits.

From a limited search it appears that:

Airride (as advertised on Outdoor bits) appears not to cover four wheel axles;
Gliderite - probably does a solution at £x,000's + vat - more than I want to pay;
AS Air Suspension quotes product AS120512 for Mercedes 408/416, but I'm not sure if this covers the 413 chassis.

The last contribution to this topic http://www.motorhomefacts.com/ftopic-22764.html mentions air suspension on a 680 but I believe that some 680's are 2 wheel rear axles, i.e a 313 chassis.

Note to moderators/forum designers - is it possible modify the system so that a single topic is listed/displayed on multiple forums? I would like this to be on 3 - base chassis, hymer and parts & accessories.

teemyob

Hello there,

It is on the cards for us to do this at some point. Having said that we are currently looking at RV's again!.

On to your questions.

Glide rite do two systems for the Mercedes 4 series, I think the one you are refering to is the FULL Rear Air Suspension as fitted to ambulances, cost from around £4,000.00. They also do a similar semi air or assisted air suspension that the others supply for similar money.

AS Air Suspension product AS120512 Should fit the 413 as the only difference between the 4XX series is the engine, the chassis will carry the same load.

Speak to our man on here at outdoor bits or try Marcle Leisure. They have a man in the know.

With regard to the kit for 4 Series Mercs, there is a difference on the chassis. Some were specified by the motohome converter with "Camping Car Suspension". However, some were not. If you don't have it, it being a thick rubber pads bolted between the chassis suspension leafs and the body, then I think you will need to buy this as well. Additional cost is around £150.

Let me know how you go on?

Trev.

gaspode · Moderator

teemyob

gaspode · Moderator

Couldn't agree more teemyob Rolling Eyes

If you want your post to be overlooked by half the forum just use one of the above titles, works every time. Wink

jemshome

For the record I didn't want to make multiple posts - in the sense that I want to have the post indexed on multiple forums, i.e. using the same disk storage for the post with a relatively small overhead for the links. In this way more folk are likely to see the helpful replies ...

I had no intention of typing the post into multiple forums.

I note that on the 'levelling' sub forum there is this post

jemshome

Trev - thanks for the reply.

The suppliers contacted have all been very helpful.

AS (I think these are the Dutch VB units, they can be seen here

jemshome

Last Wednesday we had the AS Air-suspension units fitted to the B680.

I was mistaken in thinking that the system used VB units I attach a pdf file covering the installation from the actual Dutch manufacturer.

The installation includes 2 rear single bag units, linked to a 12 volt compressor and a control unit. Control unit activates the compressor that pressurises both bags to same pressure and has separate valves to release pressure from offside and nearside bag independently. These same valves can be used with a external air line to pressurise the bags in the event of a fault in the compressor.

The design is simple and fitting is straightforward for any competent mechanic. I took the easy option of having AS UK perform the installation at Warrington.

I found AS to be very helpful and particularly so in accommodating the positioning of the compressor and the control unit.

I have had the compressor in the storage locker beneath the seating forward of the fresh water tank and the control unit in the high level storage locker above. The compressor is powered by a fused lead direct from the leisure batteries - close by beneath the storage locker. Power leads and 2 pressure tubes feed up to the control unit. The boxing of the compressor, control panel and covering the pipe/cable with conduit - has, at my request, been left for me.

I tested the unit up to 8 bar (7 bar is maximum working pressure) prior to leaving and convinced myself that there were no leaks and the rear end was indeed rising!

I had been warned that a 2 bag unit would not be able to achieve the lift I was looking for - this does not appear to be the case.

I accept that with a 4 bag unit, having 2 bags per side will mean that the pressure bags, probably operate over a large area and hence, for a given pressure, will achieve a larger force. A given increase in height of the body will then be achieved at lower pressure. This is providing of course that the 4 bag units do operate over a larger area. While improved reliability may result from lower pressure operation, the increase from 2 to 4 bags and the extra connections will have the opposite impact. You pays your money and takes your choice, I think!

We left satisfied with the demonstration.

The following two days the system was put through its paces! We travelled north on Thursday and Friday through some howling gales - the cross winds were intense and as bad as I can remember crossing Rannoch Moor on Friday. We travelled with the system at 4 bar (might be a little hard for some - but not for those of us used to Land Rovers). 680 was far more stable and suffered only minor deviation when being passed by heavy goods vehicles in terrible conditions.

Driving on and off our local small ferry at low tide was the final test. In less than a minute the system pressure was increased to 6 bar - just to be sure. Straight on and off, no problem. (Deflate back to 4 bar). Success!

Since our return, I have had chance to closely inspect the fitting. Satisfactory, but could be better. Pipes could have been routed differently so that there is less chance of them coming into contact with moving suspension units. Fortunately there appears to be sufficient slack to move the pipes and remove the possibility of contact.

Overall assessment - a most worthwhile investment, money well spent. If I had to do it over again and with hindsight, I would do the installation myself or use my very trusted local garage (operated by a real engineer of the old school!).

jem

teemyob

What a Jem!

Taking all that time and trouble, not only to type up a review, to add a .pdf download into the bargain.

I am suprised that someone has not responded or at least pressed this

.

No doubt we will click open forums next week to find a topic along the lines o