Brake fluid and bolt size for fender

[ed B]

I figured this info was already on the site but could not find it.
It has been so long since I did anything with my car I thought I try some things. I noticed the brake fluid wa low in the smaller reservoir and was hoping someone could tell me the recommended fluid to use. I knew at one time but dont recall anymore.
Mine is the light brown fluid not the purple stuff.
I also thought I'd tackle trying to fix the rusted out attachment of my front fenders behind the front wheels, underneath the body. The fender itself is in good shape but the attachment point on the inner body is rusted away. Can anyone tell me size of bolt and thread type to connect to the welded nuts (which are no longer there)?
Thank you.

[gnoplos]

Brake fluid should be the basic DOT 3 or 4

[ed B]

Ok thanks on the brake fluid info.

[dynaguy]

Most Body bolts are SAE fine thread. Not sure of which one you are referring to, I would suspect 1/4-28 or 5/16-24 thread. FWIW Pat

[ed B]

There are 2 bolts that screw into blind nuts that are connected to the inner body that hold the bottom of the dogleg of the front fender. The bolts thread straight up from the lip under the fender. It is the underside of the flat portion of the fender just to the rear of the front wheel.

[C.Costine]

My bolts are 5/16-24 but that is because that is what I put inside for nuts when I made the new inner part. Use long enough bolts to allow you to put 2-3 thick washers between the fender and the inner part. The space will reduce the trapping of dust and mud making your fenders last longer. I have switched to the purple silicone brake fluid because it doesn't hurt paint and doesn't attract moisture. It requires a complete flush of course.

[bossbob]

"I also thought I'd tackle trying to fix the rusted out attachment of my front fenders behind the front wheels, underneath the body. "

If this is rusted out, you might have to remove the fender and repair/patch the rusted inner fender piece were it bolt's into. I had to do mine.

[ed B]

My bolts are 5/16-24 but that is because that is what I put inside for nuts when I made the new inner part. Use long enough bolts to allow you to put 2-3 thick washers between the fender and the inner part. The space will reduce the trapping of dust and mud making your fenders last longer. I have switched to the purple silicone brake fluid because it doesn't hurt paint and doesn't attract moisture. It requires a complete flush of course.

Thanks. I may switch to the purple stuff later when I have time to switch out the fluid, but for now I just wanted to top off the one reservoir.
Good idea on the washer idea. Thete was a lot of trapped dirt in there when I took the fender off.

[ed B]

"I also thought I'd tackle trying to fix the rusted out attachment of my front fenders behind the front wheels, underneath the body. "

If this is rusted out, you might have to remove the fender and repair/patch the rusted inner fender piece were it bolt's into. I had to do mine.

Yes thanks. I have the fender off and plan to to cut out s small access panel on the inner fender side so I have access to weld in the replacement piece on the bottom, along with the nuts.

[C.Costine]

"I also thought I'd tackle trying to fix the rusted out attachment of my front fenders behind the front wheels, underneath the body. "

If this is rusted out, you might have to remove the fender and repair/patch the rusted inner fender piece were it bolt's into. I had to do mine.

Yes thanks. I have the fender off and plan to to cut out s small access panel on the inner fender side so I have access to weld in the replacement piece on the bottom, along with the nuts.

Ed, do you have a spot weld hole saw?

[Curtis]

The fender has:
front and top of fender
11 truss head phillips 1/4-28 screws 5/8" long
10 nuts 11 washers 11 lock washers

back of fender along pillar and top of pillar
4 hex head 1/4-28 bolts 5/8" long
1 nut 4 washers 4 lock washers
You have to remove the door for these. The 4 door hinges have 16 1/4-28 bolts.

bottom of fender at front of rocker
2 hex head 5/16-24 bolts 5/8" long
2 washers 2 lock washers

I just finished putting together bolt packs for my car restoration.
You can get a box of 25 truss head stainless from McMaster Carr
I bought the rest from Bolt Depot in stainless.
Most hardware stores will not have 5/8" long. 5/8" is both measured of original bolts and taken from the Datsun parts catalog when they had part numbers that called out material, diameter and length.

[Curtis]

All bets are off if the 69 has metric fender bolts.

[ed B]

"I also thought I'd tackle trying to fix the rusted out attachment of my front fenders behind the front wheels, underneath the body. "

If this is rusted out, you might have to remove the fender and repair/patch the rusted inner fender piece were it bolt's into. I had to do mine.

Yes thanks. I have the fender off and plan to to cut out s small access panel on the inner fender side so I have access to weld in the replacement piece on the bottom, along with the nuts.

Ed, do you have a spot weld hole saw?

I do not to believe I have one of those. Where would I use it? the bottom lip?

[ed B]

The fender has:
front and top of fender
11 truss head phillips 1/4-28 screws 5/8" long
10 nuts 11 washers 11 lock washers

back of fender along pillar and top of pillar
4 hex head 1/4-28 bolts 5/8" long
1 nut 4 washers 4 lock washers
You have to remove the door for these. The 4 door hinges have 16 1/4-28 bolts.

bottom of fender at front of rocker
2 hex head 5/16-24 bolts 5/8" long
2 washers 2 lock washers

I just finished putting together bolt packs for my car restoration.
You can get a box of 25 truss head stainless from McMaster Carr
I bought the rest from Bolt Depot in stainless.
Most hardware stores will not have 5/8" long. 5/8" is both measured of original bolts and taken from the Datsun parts catalog when they had part numbers that called out material, diameter and length.

Thanks for all the info! I had a lot of trouble getting the Phillips head bolts off the fender. I only got one off, the rest got stripped and then I had to drill them all out. Royal pain.

[Curtis]

Thanks for all the info! I had a lot of trouble getting the Phillips head bolts off the fender. I only got one off, the rest got stripped and then I had to drill them all out. Royal pain.

316 stainless truss head screws, 1/4-28 x 1/2"
https://www.mcmaster.com/screws
Go to rounded head screws.
Then phillips rounded head screw
Scroll down to:
18-8 Stainless Steel Extra-Wide Truss Head Phillips Screws