Minn Kota Homade Lift Assist - Installed

[Bill Reynolds]

I thought it best to start a new thread on this subject. I completed installing the gas springs today and wanted to share the pivot mounting dimensions and a couple of install hints.

I bought the gas springs off eBay which are part number 4048 and intended for a Jeep Cherokee hood lift assist. These springs have an 11 inch extended length and a 4 inch stroke. They mount on a 13 MM ball stud. If your springs do not come with the mounting studs, buy the ones with a 5/16-18 mounting thread.

The MK mounting bracket has two arms each on it's own pivot spaced about 2 inches apart creating a parallelogram. Since the upper arm is the one our gas spring will be attached to, we need to understand the required relationship of the lower spring mount to it's pivot. Referring to the left picture, the lower spring mount needs to be spaced in front of the upper arm pivot between 1 3/4 and 2 inches but cannot go past the lower arm pivot point ( I located mine at 1 3/4). ( It must stay inside the parallelogram). In the vertical plane, I dropped it down about 1 inch so as to have a slight downward force. This offset from the upper arm pivot point provides the cylinder compression for the lift assist.
The other end of the gas spring attaches to the upper arm at it's fully extended dimension. The longest leg of the created triangle is when the motor is in the stoyed position, so that is where we locate the other mounting stud. Referring to the right picture you can see that the mounting hole is 9 3/4 inches from the pivot point so this plus the 1 3/4 offset of the lower pivot point equals the 11 inch max extension of the gas spring. However, don't try to measure and locate for this location, it has to be exact so do this instead.
1) locate and mount the lower stud mounting position and drill and tap a 5/16-18 hole. Screw the lower mounting stud into place to use a a reference point.
2) note that the bracket on the shaft end is threaded. Back it off about two turns to give you some adjustment in either direction in case it is needed.
3) attach the spring to the lower stud and install the other ball stud into the other end.
4) With the motor in the stoyed position, swing the loose end of the spring to the desired position on the upper arm and mark the spot where the hole is to go.
Drill and tap this to 5/16 - 18 and install the mounting stud. The spring should snap into place now.

The following pics show the completed installation.


Hope this helps. It is not as hard as it sounds, but like all projects, the devil is in the details.

[billnorman1]

Per my observations, you will want your studs firmly screwed into the metal all the way and use Loctite once you establish the dimensions needed and finish checking it out. I also used nuts on the studs inside the moving arm for safety. If there is any binding or rubbing on the cylinder as it goes through its arc, add a washer or spacer as needed on the bottom stud to space the ball out.
The cost of this entire rig can be less than $30.00.
If your motor is older, this also quiets it down a lot when changing directions or adding power.
Nice photographs.

[Bill Reynolds]

Thanks for the additional information. I put stainless steel washers on the mounting studs and tightened them against the mount. One gas spring helps a lot but two takes all the weight away.

[rtlgator]

This looks great Bill and great photos, I'll be on eBay this morning looking for the shocks....and thank you Billnorman for your hints to help with this... I'll have to find the studs also and only once have I ever had to make threads so that might be a challenge for me...

[billnorman1]

This looks great Bill and great photos, I'll be on eBay this morning looking for the shocks....and thank you Billnorman for your hints to help with this... I'll have to find the studs also and only once have I ever had to make threads so that might be a challenge for me...

I'd prefer 5/16" studs over metric. If cutting threads is new to you, you could look up on-line some how to sites. You could also practice on a spare piece of metal. Don't buy a "bottoming" tap, you will be best served with a tapered tap.

[rtlgator]

Thanks for that, is the ball size 13mm ?

[Bill Reynolds]

Thanks for that, is the ball size 13mm ?

Sorry about the confusion, the ball size is 10 MM and the hex size is 13 MM and the threads are 5/16-18. The tap drill size is letter F. You may want to check Lowes - Erwin has a thread kit and their taps have a pilot on the front that helps start them straight. You will need some oil lube or if you can find some tap magic that would be great.

[billnorman1]

Thanks for that, is the ball size 13mm ?

No, the stud is either 5/16" or 8mm, the nut on the stud would ususlly be serviced with a 13mm or 1/2 inch wrench;
The ball is either 3/8" or 10mm, I think the socket on the strut will work with either.

[rtlgator]

Yep, I ordered from same eBay seller and called then, was told it's a 10mm ball and they are sending me 4 along with the struts....can't wait to install..

[rtlgator]

Yes the ball size is 13 MM and the threads are 5/16-18. The tap drill size is letter F. You may want to check Lowes - Erwin has a thread kit and their taps have a pilot on the front that helps start them straight. You will need some oil lube or if you can find some tap magic that would be great.

Thanks Bill, went to Lowe's and found Dewalt made combination drill/tap bit one step...

[Bill Reynolds]

I got to fish a few hours this morning, first time since I added the lift assist. It works great, you have to push it a little over center when deploying but there is zero weight when you lift it up.

[rtlgator]

I'm Ok with having to push a little, it's the hauling back in, no tug a war anymore...

[billnorman1]

I got to fish a few hours this morning, first time since I added the lift assist. It works great, you have to push it a little over center when deploying but there is zero weight when you lift it up.

After you use it a while that push will go away. You can also develop a quick throwing habit with the cord which will set it in the latches it just takes a little practice. Whichever, your back will thank you.

[mmbtv]

Thanks for the write up.

[MikeT1973]

Do you know the lbs. on that piston? I just put a new Maxxum on my boat and looks a great project.

[Bill Reynolds]

Do you know the lbs. on that piston? I just put a new Maxxum on my boat and looks a great project.

I don't know for sure. I have heard 2 numbers 110 and 40. I am inclined to believe the 40.

[captainrab]

What size maxxum is this?

[rtlgator]

I don't know for sure. I have heard 2 numbers 110 and 40. I am inclined to believe the 40.

Same here ???

[rtlgator]

What size maxxum is this?

Mine is a 70lb variable speed 24v Max

[Nova Kaw 650]

Nice!