Hullavator gas spring repair

For persons going through a useless discourse with Thule or any of their Hullavator dealers concerning replacing the leaky gas springs on their units, I have a reasonable solution! I worked out the details and have successfully replaced the cheap Chinese gas springs on an older model Hullavator with reasonably priced units from a Canadian manufacturer, Gemini Gas Springs at Vernon B.C. Their model per their item # drawing 415.04.235.560.225 will give you exactly what you need, 2 units at less than $50 CDN plus tax. When shipped FedEx (about $30) with tracking, you are set. Drill out the rivet pins holding the gas spring in place and replace with new semi hollow rivets of correct length. I drilled a small 1/8" hole at the base of the eye of the rod end, and used a 3 foot standard clamp to pull back the rod with a piece of coat hanger wire through the 1/8" hole after refastening the body end to the Hullavator arm. Putting the Hullavator arm assembly in a large vice makes things easier to handle! Once the rod end of the gas spring is in position, replace the shorter rivet pin and you are done! These gas springs are a bit heavier duty with slightly higher compression, so now you can easily lift up to a 50 lb kayak with little effort… and save your back!!!


Nice Going!
I remember an older discussion where someone wanted to replace the gas cylinders on their Hullavator, and they couldn’t get a straight answer from Thule in terms of differentiating between force applied by the cylinder and the lifting force of the unit. I seem to recall that the replacement cost of parts from Thule was outlandish as well. It was mentioned in that discussion how to estimate what strength cylinder would be needed, but “here’s what worked for me” advice is easier to digest, and it also proves that you don’t need to go to Thule and pay a small fortune to get your rig working again.

hullavator gas spring repair
I recently had a cylinder replaced by LS Technologies in Saskatoon. They removed the old one and put in a new one for just under $100. Really nice people to work with. It was the first Hullavator they had actually worked on. It works great. Their # is 306 683 5000.

Replacing Springs on Hullevator
Your description on how to replace the springs sounded difficult but l was ready to tackle it. My earlier model “lift” also had worn out gas struts but when l took a closer look found that the springs could very easily be unscrewed from the assembly in less than a minute. Both ends of the strut are threaded and they just screw onto the ends that are affixed to the large rivets.

The markings found on my struts indicated the manufacturer as “MDI” (since 1963) and a number 07EA was printed on the strut though l have yet to research that info. l will post further info as l find it.

First of all, thanks for this great tip. I picked up a used Hullavator on ebay, and when I discovered one of the struts was busted I thought the whole thing had become an extremely overpriced paperweight.

Can you provide some more info about the gas springs you got from Gemini? I tried searching their site for the item# you provided, but I’m coming up empty handed.

Hullavator Gas Spring Replacement
I received an email from a fellow kayaker who didn’t have the same outcome as I did replacing gas springs, and replied to him as follows…

I tried looking up the Gemini Gas Spring by the item number you gave me… it didn’t come up in their search engine. I installed the two gas springs with a lot of effort in a well equipped workshop using clamps and a wire attached to a small piece of metal strip drilled to just fit over the screw thread of one end of the piston after attaching the other end. I then used the vice on the work table to draw the gas spring back to where I could then place the retaining piece in and allow the retaining pin to take up the load. I do not see how you could possibly compress the 250 Newton gas spring by hand and hold it in the proper position while you replaced the retaining pin!!! Are you sure you got a gas spring with sufficient load to do the job? My springs have no problem lifting a 45 Lb. kayak, so I don’t think you got a heavy enough gas spring.

Since it’s been awhile when I replaced the gas springs, I don’t have the information regarding the ones I ordered, but looking back on my posting on the “” site, it seems that the ones I quoted were #415.04.235.560.225 but again, their search engine shows no result??!! Looking at the style of gas spring with the screw on ends that you have to replace with your old Hullavator ones, I would measure the extended length shown on their drawing as “EL” and then the compressed length of the Hullavator piston arm in its closed position. The difference will give you the appropriate “S” length as show on their drawing. I am looking at their drawing for item #415 at this link:

You will then have to order the closest product item fitting these dimensions (okay if the total extended length “EL” is a bit more than the fully extended Hullavator arm, but the compressed length must allow the arm to fully close and lock!). For persons having a kayak heavier than about 45 Lbs. I think you could still find a product with the proper extended and compressed dimensions, but choose a larger load of say 300 Newtons or about 67 Lbs. force. It will surely lift a heavier kayak, but will likely be a bear to install, and I would be taking it to a mechanical shop to have them install it. Then watch out when the kayak is off the Hullavator and you release it to park it… it may flip you onto your vehicle roof…LOL!!

We purchased 2 pairs of Hullavators in 2008 and after considerable use over 8 years one of the gas springs failed.
I removed the gas springs and after discussion with Mr. Henk Blok at Gemini Gas Springs (Vernon, BC, 778-475-5611) sent him one of the GS that had not failed for identification. Mr Blok then sold me four “8/19 250-555/500N M8/M8”.
The cost in 2016 was approx. $25 per spring (including HST) and $27 in total for shipping .
These replacements are the same dimension as the originals and are rated at 500 Newtons (approx 110 pounds-force).
I tried various approaches for installing the new springs and eventually found that it can be accomplished fairly easily using some clothes hanger, 1/8" wire rope, wire rope clamps (the crimp-type do NOT hold) a 5" turn-buckle and some ‘S’ hooks plus odds and ends.
I shall post my approach with photos as time permits.
To remove the old springs, with the Hullavator in the closed position, I first unscrewed the ROD end using a pair of needle-nose vice-grips. Caution: even old springs can be under considerable pressure so keep your fingers clear!
All the spring and fitting threads are right-handed on my Hullavators.
To install the new springs only one rivet needs to be drilled out: the one that carries the ROD end of the spring and that passes completely through the Hullavator. Removing more rivets makes the job more complicated not easier!
Because of the pressure in the barrel of the gas springs drilling or clamping them seems like a very bad idea.
Because these parts are under considerable constant stress, weakening one of the fittings that carry the springs by drilling a hole in it seems like a bad idea.

Are these spring heavier duty than originals. I have a 75 LB kayak. Thanks

Regarding gas spring strength:
The original Thule gas springs had no specifications on them and Thule would not provide this information so I sent Henk Blok at Gemini Gas Springs one of the original gas springs that had not failed and he determined it provided 500 Newtons or 110 pounds of force. Our kayaks, Delta 15.5s weigh about 52 lbs and the replacement springs work well although in hindsight I would go somewhat higher than 500 Newtons as it is easier to pull the Hullavator down than to lift Hullavator with kayak up.
Thule states that the load limit for the Hullavator is 75 lbs and that they provide 40 lbs of lift.
Gas springs are available in quite a variety of strengths.

Hi Tim, no longer allows PDF attachments.
Please find attached the equivalent jpg files.
Be careful and be sure that everything is well secured - these springs exert a lot of force on a small area!
I’d be pleased to try and answer any questions that arise.

130 maybe?

130 lbs sounds reasonable but I have little experience with gas springs.
I suggest that you ask Henk Blok his opinion - he was very helpful when I contacted him.

Hi. Can you tell me if your 500N 110lbs springs fit well with your Hullavator rack ? Are the arms of the racks are too difficult too pull down to lock it without the kayak on ? And was it difficult to compress the springs and fit it ?
Do you recommand the 500N ones ?

I do not currently need your instructions for the hullavator gas spring repair, but being proactive I have downloaded and printed them. You went through a chunk of work to create those instructions. It is greatly appreciated.

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Yes, the replacement gas springs are a perfect fit but note that the 500N 110lb specification does NOT describe the physical dimensions.
With new gas springs the empty Hullavator arms are easy to pull down for loading.
When installing new gas springs the compressing using a turnbuckle as described requires little effort but holding them compressed while fastening them in place in the Hullavator was by far the most challenging part of the job.
The 500N replacement in use felt the same as the original.

De nada - it was an interesting challenge.

Thank you for your answer. It is aprreciated so much.
I will order the same at Gemini.
Have a good Day.

I just order the 580N/130 lbs springs for My hullavator. I went a little heavier since my sea kayak is 75lbs. Henk at Gemini was very helpful. He knows the exact dimensions and can custom make your desired poundage. He said the 500N/110lbs are about what the originals are. I’ll keep y’all posted on the outcome.

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Hi. Which hullavator model you have ? 897 or 897xt or 898pro ? I have the 897xt. And the piece number is not the same than you indicated in an upper message.
Also do you think it is better to change the two springs or only the one broken if the old is still good ? Because I must know if I need to buy one or two springs.
For the price they ask me $33.50 each plus shipping and GST…

Hello Kayako,
My Hullavators are 897XT.
Which piece number are you referring to?
My original gas springs had no useful identifying markings.
I would recommend replacing both gas springs at the same time.

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