Bolt size for hood hinge bracket to hood

[Valvechatter]

Sorry for another Newbie question, but I am discovering the maintenance needs of my newly acquired 69 280 SL, as I spend time in the garage. There are four bolts that are used to attach the hinge bracket to the hood at the front of the car. Last evening I noticed that the outside bolt on the LH hinge bracket is completely missing and the inboard bolt is loose. Obviously, I need to attend to this right away before I have a problem. I don't want to remove one of these bolts to determine the thread size and length of these four bolts, and I am hoping that someone can advise me on the correct bolt to use at  this location. Thanks for your assistance.

Lin

[Rolf-Dieter ✝︎]

I took one of my bolts out using a 10 MM wrench. Unfortunately my Digital Vernier is out off battery so I had to eyeball the dimensions as good as I could.

You need a 6 MM bolt size having 24 Threads per inch bold head is 4 mm and across flats it is 10 mm thread length is 20 mm complete with head the bolt is 24 mm long.

You need a washer 7/8" OD x 3/8 ID" and a lock washer 5/8" OD x 3/8" ID

Caution, make sure to close your hood very slowly during the alignment. Guide it down carefully by hand. As a precaution put painters tape along the painted front and fender edges, just in case as to not to damage your paint.

I will add a photo of the bolt and wachers in a moment. EDIT ---> See bolt, washers below

[Jack Jones]

The bolt size is M6 x 15mm length, 1.0 thread pitch fully threaded. The bolt is DIN 933 if anyone asks you.  You also require 1 x 6mm lock washer and 1 x 6mm flat washer.  

[Valvechatter]

Thank you for the quick response gentlemen. Hopefully, it will just be a matter of screwing the bolt in and that I don't find the nut stripped or having crossed threads.
Warm regards,
Lin

[Rolf-Dieter ✝︎]

Lin, I had to fiddle about 45 minutes to get the bolt back in seams like there is a nut device in a blind space and it moved on me. I had to use a wire and mirror to line the sucker up in order to get the bolt back into place.

Naturally it's easier with the hud off and upside down to line up them nuts LOL I prayed it had not to come to this and am glad the screw is back in it's place.

[Valvechatter]

I was afraid that this was one of those tasks that was not going to be as easy as one might think! Will let you know how I come out after I visit the hardware store to pick up the bolt and washers.
Lin

[KevinC]

Any remedy for one nut (inside enclosed portion of the hood) becoming dis-lodged and therefore not available to accept the bolt being discussed?

[Valvechatter]

Ooh, Kevin. I have not looked yet, but don't take me there!
Lin

[mbzse]

Any remedy for one nut (inside enclosed portion of the hood) becoming dis-lodged and therefore not available to accept the bolt being discussed?

The part inside (that holds the nuts) can be exchanged, requires a hole to be cut in the side of the hood aluminium shell. Vendor SL Tech has a kit for this purpose,
see web http://www.sltechw113.com/parts.html
/Hans in Sweden

[Rolf-Dieter ✝︎]

Hi Kevin, The only remedy I see is to do one or the other.

1) With the hood open all the way use a mirror and a wire (a slight hook at the end) then using a flash light poke around to re-centre the nut device inside the hood blind spot. You will know when you have succeeded when you see the threaded section line up with the square opening in the hood. Then very carefully insert the bolt with washers in place over the bolt and pray that the nut device does not move on you. This is what I did and after 3 attempts I had susses ... nothing like success

2) With the hood removed turn it upside-down and juggle the hood until you see the thread then insert the bolt with washers. This method as you will know yourself is not recommended.

Note, if you have no other choice then to go route No, 2 make a mental note never ever to remove that bolt. To remove the hood one only needs to remove 2 bolts from one of the hood brackets. I am sure that the original design has the nut device firmly in place, I must have had bad luck that my nut was loose in the driver side corner blind spot (you can be sure I never ever will remove those bolts again). A couple weeks ago Benz Dr and his Mechanics removed my hood and the bracket on the passenger side was removed. The fellows had no problems at all to re-install the bracket on reassembly. Therefore I assume I just had bad luck with the bolt I removed to measure it for Lin.

[Valvechatter]

My other restorations have been British cars, but apparently German cars seem to follow the rule that I encountered many times before: "What appears to be simple, usually isn't, and jobs that you think will typically take minutes often involve hours."

After these questions and commentary, I must say that I am not looking forward to what I am going to find!
As you have probably noticed, the "fix" kit from SLTech is temporarily out of stock. Hopefully, I will not need it - we will see.

Thanks fellows.

Lin

[Valvechatter]

Purchased the proper hex head bolt, flat washer, and split look washer and fortunately had no difficulty in screwing it into the captured nut on the hood. Just got lucky I guess. Thanks for the help. All four mounting bolts are now nice and tight.

Lin

[gerster]

Fine to hear it was so easy Lin!

Good luck.

Greetings from the Netherlands.
Ger.

[dpreston Virginia]

This is the way the forum should work. Good quick advice and a good outcome.
Welcome to Pagoda ownership!

[Rolf-Dieter ✝︎]

DPreston,

You said "should work" actually it does work that way .... you will find that too once you look around a bit ..... I said it before and say it again "This is one of the best automobile forums I've come across"

Great members here, perhaps it is because of the type of car we all love ... not something for the young at heart  I can say this since I also drive a ///M3 and the ///M3 forum compared to this fine forum is like "Night and Day"

May all your travels be safe and happy ones

[KevinC]

Thanks for the replies to my dilemma, too. Will try this weekend.