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Hood or Bonnet

This component is part of Chassis and Body.

Definition

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  • part # - start year & end year
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Function

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Maintenance

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  • How to fix / change

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Old Yahoo content

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Hood Removal

Removing the Hood

1. Open the hood and place it in the service position (rod holding the hood open).

2. Put cardboard or painters tape between the hood and the fenders. This prevents scratches and on installation centers the hood.

3. Install an "S" shaped hook into the hole in the hood just above the spring rod. You can use an S hook off of a rubber bungee cord. With an assistant holding the right side of the hood, carefully hook the spring rod into it. Grab the spring rod, and pull it up towards the hood. Hook the rod into the S hook.

4. Remove the cotton/nylon hood safety strap.

4a. Optional: draw marks or use "white-out" paint to indicate the *EXACT* position of the hinges to the hood. Do NOT use chalk - it wipes away too easily. This is optional. I have never had to do this.

5. Loosen all four female hinge 10mm bolts (from underside of hood), but do not remove them.

6. With assistant still holding the hood on the other side, carefully remove the 2 bolts holding the hood to the hinge on the left side (side with the torsion spring), while still holding the hood up.

7. Pull the hood slightly toward the driver side, to slide the female hinge from the male pin portion on the passenger side. The hood is now free.

8. Immediately, remove the hinge, left behind on the driver side, from the car, and bolt it back onto the hood. This prevents losing the threaded plates inside the hood body.

9. Carefully place the hood somewhere safe where it will not be scratched.

A video from 2015 PUB shows the procedure: https://youtu.be/Y3RZdoj13AY

Installing the Hood:

Reverse of above procedure

Note: You need to secure the torsion spring prior to hood removal. If you dont, the spring will whip around and crush your fingers, as you pull the hood away from the car. Then you'll end up with the spring twisted 360degrees the wrong way.

Hood Torsion Bar

To Remove:

Remove the hood from the car (See Hood Removal)

Set the hood on a carpeted area and put an additional towel on the floor to protect the paint. It helps to have a friend help with holding the hood when installing and winding the bar.

Carefully release the rod from the S hook which is holding the rod in its tension state. Very carefully unwind the rod and release the tension before loosening the nylon holders (left & right plastic pieces that hold the rod on the hood). The right end 90 degree part on the bar points to the front of the car so all of the pressure inside the channel is to the bottom, rather than toward the skin of the hood. Otherwise it will not have enough tension to hold the hood up.

The rod will come out of the hood and make a sharp turn upwards. You need to pull on the end in a forwards and then downwards motion until it points towards the plastic it will sit in.

To Install:

If the hood is already installed, you will need to remove it and "wind" the torsion bar in a counter-clockwise direction and then hook with the "s" hook--this is a two person job to do w/o hurting yourself or the car.,

Twist the end of the rod 180 degrees to pre-load it.

When putting the hood back on the car, be careful of that S hook that you use to hold the rod in its tension state. Also be careful of the rod. If it gets loose, the unwind will not only scrape the paint on the edge of the hood, if your knuckles are in the way it'll break them with alacrity.

Note:

It's possible to install the right side end incorrectly and you won't have proper tension on everything. The rod really isn't a rod at all - it's a big spring with lots of tension, once wound.

The nylon pieces (left & right) are available from Miller's, Bud's, the Benz Bin, and MB dealers. They are about $15 a set. Inspect the grooved cradle on the left side prop piece. If it's too worn, the prop end of the bar could slip out causing the hood to drop too easily.

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I read an ad in The Star for a special tool ($15) to help remove the hood of a W113. Is it the tension spring that makes hood removal difficult? Has anyone ever used something like this? Do I really need it? The only maintenance things I can imagine that could require the removal of the hood would be to work on the battery, radiator, or fan.

I didn't have to remove the hood in order to change the battery. I DID have it removed to change that tension spring that holds it up, though. Maybe that's what the tool is needed for? Had my trusty mechanic do that...

I have had the hood off more times than I wanted. It is off right now as I work on the engine. My method of hood removal requires two friends and a couple of towels. I place the towels between the hood and fender to help avoid scratches. I raise the hood. Then I have a friend on each side of the hood to hold it while I unbolt the hood. The hood is then removed and stored in a safe place. No damage to the car or hood yet.

Will Samples says: I have also seen the $15 "tool" for removing the hood on the W113. I too assume the tool is for the tension spring. Most mechanics just use the cloth safety strap and tie it to the spring, so the spring cannot unwind. The "tool" is probably similar to one a local mechanic made out of several strands of coat hanger. It has a hook on each end. One end for the spring, one for hooking into the holes in the side of the hood. The hood spring is under tremendous tension and should you ever let it unwind, it will remove fingers or at least put a hole in the hood. One should not have to remove the hood to work on the battery.

I'm having a hard time putting my hood back on. The hinge brackets under the hood lid keep moving on me. Does anyone know an easy way to do this. These are the hinges that attach to the body with male extensions and the hinges that connect to the hood itself. It's the bracket behind these hinges that move once the hinge is loosened. Help!

I always put the side on with the prop rod first. Just screw it on to the hood and pull the prop rod into place. A helper at this point is a good idea. The hinge on the other side can be positioned and then mounted.

Getting the hood to fit takes some moving. I usually adjust the hood up or down first and then side to side. The actual hood gap you have and how well it's done will determine how good it fits in the end.

Dan Caron says: if the car has new front fenders it may not fit at all if they were installed poorly or if the hood was replaced it may not fit all that well either. Each hood was fitted to the body at the assembly line by hand forming and filing. If you look at the underside of the hood at the back you will see a 3 digit number. This number will be on all kinds of parts on the car and they all match your body. A replacement hood can be made to fit - it's just more work.

I normally only undo one hinge and then slide the hood off from the other. Maybe you could fit the left hinge first before offering the hood up to the car. As Dan says, a helper is essential so as not to dent/scratch the hood.

I usually do this by myself. With the hood open I slide clean towels or rags between the fender and hood at the hinges. I then loosen the hood bolts and slide the female hinge towards the center of car. I then loosen both male hinges but without removing the bolts. I then slowly work the hood out one side at a time. To Dans point, it may depend on the fit and I do not have the numbers stamped in my hood and generally spend about 30-40 min. adjusting. I install the same way. Attaching hinges to body parts first very loose, don't forget the towels, and slowly working the hood in place. A pitching wedge used to hold the hood in the open position is helpful as well.

I recall that if you are as absent minded as I was you can actually manage to mount the hinge onto the body the wrong way round. This will result in your hood sitting in very wrong fashion, so make sure youre right from the start. A very neatly mounted hood is so crucial for appearance, especially with light coloured cars (uneven gaps are only too common).

Bought a new hood tension rod for my 230 SL as the old one had rust and looked bad. It took me 2 hours to slip it in, wrestling all the way. I t takes some considerable muscle to put it in, but once in it keeps the hood up nice and snug. When I installed mine, I left all the screws out the hold the grey plastic thingies that position the torsion bar and taped with duct tape some rags onto the edges of the hood that would be affected. Put on a pair of heavy gloves and put the rod thru and stood on the passenger side and then wrestled the end inside the opening on the hood for the rod. After a lot of swearing and cursing to the MB designers, it finally went in. The hood now opens really easily, light enough to open it with your pinkie finger. I am 6'7" and used to play football in high school. It is far easier to remove the hood from the car and install with the grey plastic thingies and then reinstall the hood. Mind you not to remove the four 10mm bolts on either side from the hood side, but remove two 10mm bolts from either side from the body (fenderwell) side. You can slip the opposite end off the pivot pin.

The bar (which is connected to the bottom side of the hood) is not adjustable. Only the holder is adjustable, forward and back, by loosening the two screws, one of which also retains the strap. This adjusts the full open point, where the bar latches into the bottom of the groove. If it slips out of position, allowing the hood to fall, you need to remove it and reverse it as the notch is getting worn. Mine is worn on both sides so I performed a temporary fix by drilling a small hole about 1/4 inch down from the top, to intersect just above the groove and installed a small roll pin (cotter pin would also work). I now get a definite click, when I raise the hood to full open. I have to raise the spring- loaded bar slightly to close the hood. I don't see how the bar could slip sideways out of the groove, as this rod slides in the groove when opening or closing the hood, acting as a spring assist.

I have been told that the steel rod that is supposed to hold my hood open is installed incorrectly. Since I am forced to hold the hood up with a stick I tend to agree. Would anyone be willing to take a picture of the correct installation of the rod and post it in the hope that I can see my mistake?

I always just remove one side and the hood will slide off the other pin, gives fewer variables for realigning when you put it back on... I've done it solo too many times... I generally undo the two bolts holding connecting the hinge to the hood itself, leave the hinge hanging, and pull towards me, slides off easily... I prefer messing with the drivers side, and leaving the passenger side alone, but it'd work the same either way... Anyone else have another method?

I've done it too many times and use a bent up coat hanger to hold the hood tensioner in place against the frame of the hood after taping up all the edges with good strong tape-not too strong as to peel the paint off. Unscrew the two 10mm bolts from the hinge to body and then slide the hinge forward to remove the pivoting part. Then lift the hood carefully upwards and slip it off the opposite hinge. Easy to remove, but hard to install, it is usually best to scribe into the paint the outline of the hinge bracket, so you can align it exactly as it was before. Beware: sometimes there are small metal shims or washers on the pivot axle to keep the hood to one side, or the other. It also helps me to prop the hood open on the firewall side with a roll of paper towels.

Pete Lesler: this is the best way. Only remove or slide one hood hinge plate out of the way. It would also be beneficial to scribe the position of the plate on the underside of the hood carefully so not to lose alignment.

The hood prop is under tension from it's "spring" design. When removing the hood, it will want to fling itself around torward the leading edge of the hood. I hear it is extremely difficult to get back into place.

The hinge is held to the hood with two 10mm bolts...one of my bolts goes right into the hole, no tension, no way to tighten it, it just falls in...a buddy says that there should be a nut fixed to the inside of the hole to catch the bolt, maybe fell off... But the hinge attaching area is a closed box with no way to get inside to replace the missing nut...suggestions?

Two options for self tapping sheet metal screws (I have done both): 1. Have a spot weld applied to all of the wholes and then re-tap them. I can't remember the name of the welding process-tig or mig, but it relates specifically to aluminum. My restoration mechanic did this during the restoration; 2. Get some 2 part epoxy which is used to repair engine parts-like the JB Weld product. Mix it and apply to the area, let it harden for 24 hours and then re-tap. For the screw holes in the door that are for threaded machine screws, I used helicoils, which are thread inserts. You re-tap the original hole and then use the thread insert. My passenger door pull had holes that were stripped as you described and I tapped and used thread inserts which allowed me to use the original machine screws.

I had a similar problem when I removed the hood for removal of the radiator. The hinge bracket (male) is bolted to the hood via a pair of nuts that originally rode in a track that held the nuts while allowing foreward and aft adjustment of the hood. In my case the tracks were worn and while the nuts were there, one of them could not be reached while the hood was in the position necessary for installation. My fix was to remove the hinge bracket (female) from the inner fender well mounting position. Bolt the underhood bracket loosely to the hood, place the female bracket over the hood mounted piece, then bolt the female bracket back. If you do this, be sure to mark the original bracket position to make adjustment after reinstallation easier. This is a faily common problem and I have seen a piece for sale (SL Tech?) that similates the original track concept. However, this will require considerable work and TIG welding.

The hood release cable broke. The very end of the hood release cable (which has a metal termination piece) broke where it was connected to the release lever. I searched the archives and had trouble finding info on it. Anybody have any ideas / suggestions / thoughts on how much this might cost?

Joe Alexander: clamp a pair of vicegrips on the broken wire end and pull. It will release. Order a new cable as soon as possible. The cables are adjustable at the engine compartment end. It should be adjusted so that the release lever does not need to travel too far in order to pop the hood. Over travel of this lever is what fatigues the cable and causes it to break.
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