SP36 Engine hatch--gas springs?

[nbedinger]

About replacing the gas springs (struts) that assist with lifting the radiator/engine hood---

The dimensional spec of my existing springs is something pretty close to:

Length (collapsed): 21"
Length (extended): 32"
Ball stud on piston end
Steel blade on other end
Locking? Yes, but only one strut has a lock.

Anyone have a PN or a resource for good SP36 gas springs?

Elsewhere on the WOG I've read that the PT40's and WLWB gas springs for the hood need to be 250 lb springs (each). Are those hoods the same as an SP36? Anyway, the weight-lifting rating of the springs is one parameter of interest when working out which gas spring is right.

Some discussion about whether to buy Stabilus brand, or order on spec from a supply house like Orr and Orr, or McMaster-Carr. Cost is a driver--some WOG bloggers prefer to buy German import (Stabilus brand), others prefer to experiment with supply house offerings (for less money). I want a long-last, hard-working gas spring, not too interested in risking my $$ on unproven gas speings. Is Stabilus the one for me?

Stabilus offers springs with seals to operate in hot environments up to 89C. Located by the radiator, I imagine heat is a big factor determini8ng the useful life of a rear hatch gas cartridge. Haven't seen any info about heat tolerance in other brands. Is this a factor to be factored in spring selection, or is the rear hatch environment OK for whatever gas spring I can source from pipular catalogs?

Sooooo... I nedd gas springs. Can I use the ones other Wandferlodge models use? Is Stabilus the way to go? Any help appreciated

[Rick]

Ned, I used Orr and Orr last time I had to have Gas Springs. They had what I needed in stock. The springs were Stabilus brand. I you will need is the # off your old ones.

http://truck-hardware.orrorr.com/category/gas-springs

[Dieselbird01]

Originally Posted by nbedinger

About replacing the gas springs (struts) that assist with lifting the radiator/engine hood---

The dimensional spec of my existing springs is something pretty close to:

Length (collapsed): 21"
Length (extended): 32"
Ball stud on piston end
Steel blade on other end
Locking? Yes, but only one strut has a lock.

Anyone have a PN or a resource for good SP36 gas springs?

Elsewhere on the WOG I've read that the PT40's and WLWB gas springs for the hood need to be 250 lb springs (each). Are those hoods the same as an SP36? Anyway, the weight-lifting rating of the springs is one parameter of interest when working out which gas spring is right.

Some discussion about whether to buy Stabilus brand, or order on spec from a supply house like Orr and Orr, or McMaster-Carr. Cost is a driver--some WOG bloggers prefer to buy German import (Stabilus brand), others prefer to experiment with supply house offerings (for less money). I want a long-last, hard-working gas spring, not too interested in risking my $$ on unproven gas speings. Is Stabilus the one for me?

Stabilus offers springs with seals to operate in hot environments up to 89C. Located by the radiator, I imagine heat is a big factor determini8ng the useful life of a rear hatch gas cartridge. Haven't seen any info about heat tolerance in other brands. Is this a factor to be factored in spring selection, or is the rear hatch environment OK for whatever gas spring I can source from pipular catalogs?

Sooooo... I nedd gas springs. Can I use the ones other Wandferlodge models use? Is Stabilus the way to go? Any help appreciated

Hi Ned,

I can’t help with a part number for your SP but I can tell you that most (if not all) of the gas springs that I’ve ever bought from Orr & Orr were Stabilus brand springs.

I started buying Gas Springs from Orr & Orr back in 2001. I replaced all of the gas springs on my 84 ½ PT-36 with gas springs from Orr & Orr and I used Orr & Orr to supply gas springs for some of our industrial equipment at the factory where I worked.

From Orr & Orr’s web site:

Orr & Orr Inc. is proud to be a Master Distributor for Stabilus Gas Springs. We believe they are the finest Gas Spring on the market.

[nbedinger]

Ho boy, finally solved my spring puzzle to my satisfaction, and with a few missteps taken. I destroyed springs in the process, maybe someone will benefit from my experience.

First, I measured and decided I wanted springs 32-inch long. Didn't find them at Orr&Orr or McMaster-Carr. The Stabilus distributor pointed out that Bluebird springs should be ordered through Bluebird, and I'd need a P/N, which I did not have. So I settled on 36-inch springs. My thought was, how difficult could it be to compress a gas spring and install it? In a world full of mechanical advantages using levers, screws, hydraulics, and an extensive fringe of internet-active monkey/scientists replacing gas springs on their hatchbacks, it just seemed like I had a decent chance of finding a way to install a too-long spring.

For gas pressure, I found 250-pound variable pressure locking springs--they have a tiny allen head screw to bleed pressure down. Not cheap.

I found it virtually impossible to compress these, but I had initial success using screw-type pipe clamps from my woodworking toolkit. I got the springs compressed to the required length, but then couldn't transfer the compressed spring to the coach due to limited work space around the lower mounting brackets.

I entered a dead-end spiral of experimentation, frittering away $10s and $20s on angle iron, nuts'n'bolts, threaded rod, etc. From this I learned that many people on the internet claim to have done things to compress and install gas springs that are are in fact quite dangerous, especially when 1-inch-wide cargo straps are involved.

In my driveway was a growing pile of failed attempts at getting this done. It started to rain. Time for Red Bull. Inspiration struck as darkness fell--I turned on the driveway lights, clamped the spring shaft in a vise (protected with innertube rubber), cut the long end of the spring off at the right length and then cut new threads for the end fitting. Alreet! This is the way to go.

Installed springs. Wow, 250lb springs are too strong, I could swing from the hatch. Gassed them down in small increments until something went wrong and my tiny allen wrench wouldn't engage with one spring's bleed screw. It went dead flat out of air. Ordered a new spring (non-adjustable, @100 lb this time).

Cut and threaded the new spring. With two good springs on the hatch, it worked really well, and I was pleased. But yes, friends, something went wrong. I had used the metal right-angle ends on the springs, and apparently the geometry wasn't exactly right, causing one spring end to bind instead of swivelling when the hatch opened/closed. The short threaded stud on the end of the one remaining variable-pressure spring gave up and broke off. Ordered a new spring and four metal rod ends (eyelet type).

This time a new 36-inch 150-lb spring, cut and threaded it, and installed it with straight metal end eyelets, leaving the nuts loose to help the springs tilt as the hatch travels up and down. Converted the remaining good spring to eyelets at the same time. This seems to be the magic plan for me, as they've been working now for a month.

An ideal end piece for these springs might be something more like the rod-ends used on the hatch hinges--these attach to "H"-shaped hatch bracket to the coach. Rod ends are readily available from my local bearing supply house, so when I feel the need to conduct a new experiment (to keep my mind young), I may try making a gas spring with rod ends. The obvious benefit would be a gas spring now with 1-2" of adjustable length. See rod ends here:

http://www.amazon.com/b?ie=UTF8&node=16411241

I've now got about 250-lbs total lifting force between the two springs. They don't fling the hatch open when I release the latch, but they do hold the hatch up high enough to swing the radiator.

The rod-ends I mentioned above (on the hatch hinges) are notable in this context because they screw on, providing adjustment for positioning the hatch for appearance and positive engagement between the latches on the hatch and the catches on the coach. The position of the hatch DOES affect how long the spring needs to be.

My hatch sits a bit low on the left, revealing body rivets at the top (behind the black rubber trim on top of the hatch). Still, the hatch appears to be one consistent distance above the bumper--the gap doesn't look smaller on the left side. Anyway, it looks like adjusting the hatch position (up/down) looks like it ought to be easy, and this should be done BEFORE measuring for spring length.

I'm all ears if anyone can tell me the factory technique for adjusting the hatch position. It obviously involves screwing the rod ends in/out, but it would be nice if there were a simple approach, like:

"Start with two fingers of space between bumper and hatch. Adjust top rod ends until 13 threads are exposed..."

Hope I haven't scared anyone off the task of replacing gas springs. It is fiddly and frustrating, but all told (with a hacksaw, tape measure, vise and a $2.00 thread cutting die), not much worse than finding/installing windshield wipers.

Having fun,

--Ned

[LLJ53]

I have found the replacement for the gas springs (struts) for the engine compartment on the SP36.
You go to McMaster-Carr <https://www.mcmaster.com/> and you order a qty 2 of 9416K54 (Gas Spring 30.02" ext Length, 175 lbs Force) and qty 4 of 59935K53 (Ball Joint Rod End, M8 x 1.25mm internal thread, right hand).
The gas spring has an extended length of 30.02" but when you add a Ball Joint Rod End to each side it comes out to just under 32". I just replaced both struts on my bus and 175 lbs struts work out great. The lid opens, clears the radiator, stays open and closes nicely.
Good Luck,
-- Larry

[P Surgeon]

Ned,
Nice article on replacing your springs, (I got a good laugh because I had gone through the same agony as you). I replaced mine about a year ago with springs from McMaster-Carr. Had very similar experiences like you did. First springs were too weak. Second set was about right, maybe a touch on the weak side still because I had to use a prop to keep the hatch up enough to open the radiator.

Larry,
Here's my question: are your shocks from McMaster-Carr still working ok. This spring when I went to open the rear hatch the McMaster-Carr shocks weren't providing any assistance any more. Don't know if the high heat of bay and then sitting in the cold over winter did them in?

Thanks,
Pete

[isp2952]

Originally Posted by P Surgeon

Ned,
Nice article on replacing your springs, (I got a good laugh because I had gone through the same agony as you). I replaced mine about a year ago with springs from McMaster-Carr. Had very similar experiences like you did. First springs were too weak. Second set was about right, maybe a touch on the weak side still because I had to use a prop to keep the hatch up enough to open the radiator.

Larry,
Here's my question: are your shocks from McMaster-Carr still working ok. This spring when I went to open the rear hatch the McMaster-Carr shocks weren't providing any assistance any more. Don't know if the high heat of bay and then sitting in the cold over winter did them in?

Thanks,
Pete

This is an old thread and Larry sold his bus and I haven't seen him on the forum since. After selling some still monitor it, but since he doesn't own his bus anymore he may be of no help to you.

[nbedinger]

Originally Posted by P Surgeon

Ned,
Nice article on replacing your springs, (I got a good laugh because I had gone through the same agony as you). I replaced mine about a year ago with springs from McMaster-Carr. Had very similar experiences like you did. First springs were too weak. Second set was about right, maybe a touch on the weak side still because I had to use a prop to keep the hatch up enough to open the radiator.

Larry,
Here's my question: are your shocks from McMaster-Carr still working ok. This spring when I went to open the rear hatch the McMaster-Carr shocks weren't providing any assistance any more. Don't know if the high heat of bay and then sitting in the cold over winter did them in?

Thanks,
Pete

Hi Pete--

Fun project if you can keep the cost down

I moved on to replacing gas springs in the basement bays. All were straight-forward using spring length except the battery compartment--if I remember correctly there was a problem getting a new spring in there with the batteries in place.

Have fun.