How to attach seal between hood and cowl?

[jsera]

Hey guys, I have installed the seal that goes between the hood and cowl by simply putting it in place with the cowl over it, but noticed that both the seal and cowl have holes that run along the firewall. What is it that goes in those holes? Anyone have any pics?

[Hart_Rod]

Screws

[jsera]

Originally Posted by Hart_Rod

Screws

I didn't notice any holes in the firewall section under the cowl for them? Maybe my body guy filled them?

Are they just self tapping screws?

[67ChevyRedneck]

These are the "official" screw for the cowl. Most parts houses carry them. Most places call them "hood to cowl seal screw"

[jsera]

Thanks for the help guys!

[71CHEVYSHORTBED402]

The cowl panel (a.k.a. outer cowl) mounts to the top of the inner cowl with six phillips head tap screws with integrated washers. The screw threads are #10" x 5/8". These screws also hold the seal in place.

[Robznob11]

I believe that ther are little black clips that snap over the lip much like the ones napa sells in the balkamp line. They have a hole for the screws to go into and pull tight. With out these you will need much larger than a 10# im in the same boat. Bodyman removed the oe clip/nuts

[Robznob11]

Well it may just be the case mine had the wrong screws put in it at one time , i ordered the correct screws from gmc pauls and they are to small to get tight. I saw that i had one u nut up where the stainless screws went and no others. I made the assumption that they must have all required a u nut. I guess even if they dont it may still cure the problem . But im worred about scratchint the paint trying to remove the cowl😳

[71CHEVYSHORTBED402]

Sorry dude, re-posting this which was between your two posts. I got confused, and it's so easy. From your last post, they sell you MM instead of SAE?

You mean U-nuts? If so that's not the case, at least by my experience. The cowl uses four U-nuts with four stainless steel screws, also #10. The SS screws are not used to mount the seal. Those per the picture above (six total) are, and they tap into the sheet metal only.

If body dude sealed up the holes then bummer. If it's painted, then it was suggested to me you that you use a good step bit. I'm green, but I'd say a high speed drill, masking tape and perhaps a wax lubricant are in order. If necessary I'll measure where the holes are located factory. 71 factory anyway.

[FirstOwner69]

Here's a thread from last week where the conclusion was that the screws are actually #8s. Best to start small. You can always go larger.
http://67-72chevytrucks.com/vboard/s...d.php?t=728373

[71CHEVYSHORTBED402]

Originally Posted by FirstOwner69

Here's a thread from last week where the conclusion was that the screws are actually #8s. Best to start small. You can always go larger.
http://67-72chevytrucks.com/vboard/s...d.php?t=728373

Funny you mention it. I double checked and could insert a fair portion of the tip into #8 on my gauge. Maybe my gauge is wrong, but I haven't seen any other indications. Agreed, start with #8.

Edit: Or maybe I have the wrong screws? They look right. I'll have to check my other truck.

[71CHEVYSHORTBED402]

Well I checked my other truck and found it needs a new cowl seal............Why do I feel the sacrificial beast for the money pit is just another money pit?

Also found the screws are #10. In fact, the screws sent me compliments Firstowner, I believe, are #10 as well. Could be the gauge is wrong, but it's just a hole. I can't see how they can screw that up pardon the pun. Doesn't mean they didn't. I'd still start with #8 as suggested.

Say Jim, I see your gauge etc in the other thread. Any chance they vary by factory/year? That seems odd to me, but then someone's gauge is wrong, though #8 worked for the OP in that thread.

[kda2000]

Went through this just a couple of weeks ago -- Have original screws, look right, in the bag with the stainless ones where I put them -- but 3 of them would not tighten -- holes were enlarged -- they were #8s, ordered some new from a vendor, they came #8, been looking for same style #10 SEMS black oxide -- hard to find. since these do not have J-nuts like the ones near the windshield (where the stainless screws go) you have no choice except bigger screws, or weld them closed and redrill. (or JB-Weld a small piece of metal behind the original hole and redrill for a #8). I think the holes were drilled slightly large at the factory, years of weather and taking in/out and they get enlarged and get "stripped" - common problem. -- Ken

[71CHEVYSHORTBED402]

Originally Posted by kda2000

Went through this just a couple of weeks ago -- Have original screws, look right, in the bag with the stainless ones where I put them -- but 3 of them would not tighten -- holes were enlarged -- they were #8s, ordered some new from a vendor, they came #8, been looking for same style #10 SEMS black oxide -- hard to find. since these do not have J-nuts like the ones near the windshield (where the stainless screws go) you have no choice except bigger screws, or weld them closed and redrill. (or JB-Weld a small piece of metal behind the original hole and redrill for a #8). I think the holes were drilled slightly large at the factory, years of weather and taking in/out and they get enlarged and get "stripped" - common problem. -- Ken

Go figure. I was prepared to drop the subject but obviously haven't. Odds I'd have three sets of #10 when they're supposed to be #8 doesn't seem that high to me. I checked my gauge against this and that's from marked packages and it checks out. Only exception was my #8 sheet metal screws are a tight fit, but they do insert into the gauge. At any rate, just for thrills I'll get a digital similar Firstowner's.

I've concluded not all #8, #10 etc. are equal........Close is good enough I suppose, varied by finish etc. I've also found that at times, a smaller tap screw can tighten where a larger tap screw was. For example, someone mounted the vacuum canister to the evap. box using the wrong screw on my 72. The correct screw tightened up.