1. Introducing the smashing new Team FIAT T-Shirt !! To order yours click here : Team FIAT T-Shirt

DIY - Gas struts to open bonnet

Discussion in 'Do It Yourself' started by PatchyBoy, Jan 11, 2016.

  1. PatchyBoy

    PatchyBoy Esperto

    Messages:
    2,438
    Bangalore
    I have this habit of cleaning the engine bay as frequently as I clean the car. I also check the fluid levels every week, sometimes more often, depending on the car usage. While the boot lid is held open by gas struts, sadly we have to use the OE prop rod to hold the bonnet open. I had noticed the bonnet being held open by gas struts in luxury cars and wanted the same for my car too.

    After checking the engine bay for options and ensuring feasibility, the first step was to do some calculations and decide on what struts will be required. Here is how the calculation is done:
    View attachment 85701

    The above calculations with some physical measurements taken from the car, led me to the conclusion that I will need struts about 430mm - 440mm extended length, 160mm - 180mm stroke length and rated for 325N. I searched for such struts and then realised that our own Punto boot struts are an ideal fit - 436mm extended length, 170 mm stroke and 350N rating. That it was readily available from FASS/99RPM was an added bonus. The Punto also has a screw type ball pin on the tailgate, which can be used.

    It was time now to design brackets. The Linea has a raised metal strip along the inside edge of the fender inside the engine bay, with three unused holes. It would make sense to design a bracket to fit inside this point. Also, the bracket that fits on the bonnet itself, will need to be designed to make use of the two screws that the hinge uses now. That way, the installation will be completely reversible, with no permanent changes to the car. With these parameters in mind, after a few iterations of failed prototypes, this final design was arrived at. This was then laser cut from sheet metal, CNC bent and powdercoated in matt black.

    View attachment 85702

    To be as professional as possible and to not have to worry about rust, I decided to get the brackets made of 2.5mm stainless steel sheet, use stainless steel fittings and also use a silicone sheet sandwiched between the bracket and the body, to avoid damage to the car surface. The nuts chosen were nyloc, to avoid loosening over time due to vibrations.

    Parts used with cost -

    1. 2.5mm SS brackets, powdercoated in matt black - ₹ 300 each x 4 = ₹ 1200
    2. Stainless steel fittings - ₹ 75 per side x 2 = ₹ 150
    3. Fiat part number 51778432 Strut - ₹ 904 x 2 = ₹ 1808
    4. Fiat part number 51762519 Pin - ₹ 79 x 4 = ₹316

    Total cost of the project - ₹ 3474.

    A couple of fellow Linea owners and a Punto owner were also interested, so we got the brackets made in bulk.

    Installation process -

    Step 1 - Fit the top bracket to the engine bay as shown in picture \
    View attachment 85703

    Step 2 - Fit the bottom bracket as shown in picture
    View attachment 85704

    Step 3 - Screw in the ball pins to both brackets
    Step 4 - Pop the struts in
    Step 5 - Stand back and admire your work :)



    Caveats -

    1. After fitting the top brackets to the bonnet, close the bonnet and check alignment. Adjust if required.
    2. Remove the OE prop rod. It is just held in place by one plastic clip.
    3. You will also need to either remove or trim the rubber pieces on either end of the engine bay, where it meets the windshield area, to accommodate the struts in the bonnet closed position.
    4. While I went with two struts, one strut will also do the job. It will also cut the cost in half.
    5. It is not possible to fit two struts on the Punto. There is insufficient space on the passenger side.
    These brackets will not fit the EVO. Only the Linea and the old Grande Punto. If any of you want to go for this setup, you can get the struts and the ball pin from FASS/99RPM. If you need brackets and fittings, I can arrange for it as per the cost above (plus courier, of course) or you can get it fabricated in a nearby friendly fabrication shop.

    Thanks for reading.
    Last edited: Jan 11, 2016
  2. Anirudh

    Anirudh Novizio

    Messages:
    29
    Mumbai
    mumbai
    Linea T-Jet
    Realy realy nice. I will try this on my car too. Thx a lot
  3. Ravi_M

    Ravi_M Regolare

    Messages:
    323
    Indore
    Indore
    Linea 1.3
    Great job @PatchyBoy. I am inclined to ask you for the parts. It is now a month or more since you are using it. Have faced any problem?
  4. Chandu1476

    Chandu1476 Timido

    Messages:
    2
    Bangalore
    @PatchyBoy: Realy nice. Can I get these 2 items couriered to my address if possible. Please let me know.
    1. 2.5mm SS brackets, powdercoated in matt black - ₹ 300 each x 4 = ₹ 1200
    2. Stainless steel fittings - ₹ 75 per side x 2 = ₹ 150
  5. PatchyBoy

    PatchyBoy Esperto

    Messages:
    2,438
    Bangalore
    The setup is working fine and there are no issues. I will have to reorder the brackets from the fabricator and there is a minimum order quantity of 5 sets, to get these prices. If there are enough interested people, I can re-order.
  6. Gurjit Singh

    Gurjit Singh Timido

    Messages:
    20
    Jalandhar
    Jalandhar
    Linea 1.3
    @PatchyBoy: good project.
    I am also interested to get these items couriered to my address. Please let me know how can we proceed further.
    1. 2.5mm SS brackets, powder coated in matt black - ₹ 300 each x 4 = ₹ 1200
    2. Stainless steel fittings - ₹ 75 per side x 2 = ₹ 150
  7. PatchyBoy

    PatchyBoy Esperto

    Messages:
    2,438
    Bangalore
    OK. So we have
    1. @Chandu1476
    2. @Gurjit Singh

    Please add you names to this list and I can re-order when we have five orders.
  8. jumu

    jumu Superiore

    Messages:
    969
    Chennai
    @Patchyboy,I appreciate your ceaseless endeavour to innovate. I have just a question. In case of a frontal impact once the bonnet lock gets disengaged, under normal circumstances, this steel bonnet will also form a crush resistant member, but in this case with the fixing of a hydraulic lifter, wont the bonnet be hurried into opening or lifting from its resting position. Correct me if I am wrong. Just a brain storming.

    Abdul
    Gurjit Singh, ghodlur and asimpleson like this.
  9. PatchyBoy

    PatchyBoy Esperto

    Messages:
    2,438
    Bangalore
    @jumu - That is a very good point. These struts do not open the bonnet on their own, when the bonnet is unlocked. The bonnet has to be physically lifted about 40 percent of the way, before the struts take over. So, in case of a collision, I would theoratically expect the crumple zone behaviour to be unaltered. Sadly, there is no way of finding out :)
    Gurjit Singh, asimpleson and jumu like this.

Share This Page