Questions on radiator duct (105506)

[jawn101]

Today I decided to tackle the install of my new radiator duct (http://store.delorean.com/p-9672-radiator-duct.aspx) - thought it should be an easy job since it's a two piece assembly and would slip into place easier than the original. But of course I ran into some problems.....

- Despite several applications of liquid wrench over the last few days, I still managed to snap two studs off my rock screen. That isn't a huge loss as it was complete rusty trash anyway. Does anyone know if those studs can be removed and replaced? I'd rather put it back in for now than buy a new one immediately. If not, oh well.

Here's a shot of what was left of my old duct and the studs before they snapped.
http://dmctalk.org/attachment.php?attachmentid=8634&d=1330290686

- I've finally encountered spinning rivnuts - never found one on this car yet. But of course with my luck, I think they're in the worst possible spot. The bolts I can't remove are the ones to the lower corners of the duct - all the way to the right, into the fiberglass in this shot. Any tips on how to remove that bolt and fix the rivnut?
http://dmctalk.org/attachment.php?attachmentid=8636&d=1330290693

- Is the duct supposed to go underneath (secured by) or on top of (not secured by) the lower radiator support bracket in this picture? As you can see my duct was completely gone so I have no clue how it was originally attached. Will the fiberglass repro DMCH duct be able to handle the strain placed on it by going inside this bracket?
http://dmctalk.org/attachment.php?attachmentid=8635&d=1330290689

I sort of question if this duct is even worth it. The original plastic one looked a lot better than this reproduction and honestly I'm not sure if this will even last once installed. It seems like brittle material in a place where it really needs to be flexible, unless I'm misreading the properties of the fiberglass...

For those who may not have seen the new one, here's a few pics of it...

http://dmctalk.org/attachment.php?attachmentid=8637&d=1330291121

http://dmctalk.org/attachment.php?attachmentid=8639&d=1330291128

http://dmctalk.org/attachment.php?attachmentid=8638&d=1330291124

[DCUK Martin]

The duct is definitely worth having

The 2-piece duct is poor in terms of fit and finish but it will do the job and you haven't got another choice anyway.

Rip the rivnuts out (crunch!) and replace with jack nuts. You won't be able to do this on the top left with the radiator in place unless you can find a smaller riv nut tool than mine...

[jawn101]

Fortunately the upper nuts are fine. Just the lower ones are messed up.

I have had the car over a year with no duct, and with my upgraded radiator and fans I have never had any overheating issues. I was doing the duct for looks mostly but I think nothing at all would look better than this shoddy fiberglass mold. I'd like to have it for completeness sake but.....

[jawn101]

I ordered a new rock screen, so that's solved. As for the jacknut tool, I don't have one at all - just a standard riveter. Is this the sort of thing you mean, Martin?

http://www.harborfreight.com/45-piece-threaded-insert-riveter-kit-1210.html

[Chris4099]

- Is the duct supposed to go underneath (secured by) or on top of (not secured by) the lower radiator support bracket in this picture? As you can see my duct was completely gone so I have no clue how it was originally attached. Will the fiberglass repro DMCH duct be able to handle the strain placed on it by going inside this bracket?

I've never installed the DMCH unit, but with the original you wanted it to go above the bracket so the duct would be against the radiator. If it's below, there is a gap that allows some of the air to escape and not go through the radiator. You should be fine either way though. As you mentioned, you were OK without the duct at all and mine was below the bracket for decades until I finally installed it properly last year after a radiator replacement.

It's too late now, but you can repair the rock screen. I snapped 4 of the 5 on mine! I drilled holes at the old locations and tapped threads. I then used some M6 stainless steel bolts with red loctite on the last few threads. So once screwed in, the loctite held them in place. You do see the bolt heads behind the grill, but that's no big deal.

[jawn101]

I figured it could be repaired, but it was so rusty and warped that it really wasn't worth it ultimately. Thanks for the tip though :)

I have a new screen and some other misc stuff coming from Houston right now, so we'll have to see if this fiberglass is really up to the task of being bolted in under those brackets. Meanwhile I have to go find a jacknut tool and get those two spinning rivnuts figured out.

[DMCMW Dave]

Meanwhile I have to go find a jacknut tool and get those two spinning rivnuts figured out.

The upper rivnuts are factory-installed in the wrong place, and the factory used some steel shims (the same ones that go under the door hinges) to grab the duct. Sorry - no photos handy at the moment.

[jawn101]

The upper rivnuts are factory-installed in the wrong place, and the factory used some steel shims (the same ones that go under the door hinges) to grab the duct. Sorry - no photos handy at the moment.

Yep - I have those in place for the upper ones. It's the lower ones that are my problem, the one with the bolt head still visible in my pic above

[stevedmc]

I've got the DMCH radiator duct and while it appears to be flimsy, it is actually easy to install and has proven to be durable. Lets just say the test it went through damaged my radiator but the duct managed to survive.

[jawn101]

That sounds... Unfortunate, but is good to know. Thanks Steve! I will stop by HF on the way home from work and get that jacknut kit, so I'll be ready to go when the rock screen arrives.

Steve, do you have any pics of your duct installed? I'm still curious about installation order and orientation re: the lower arms. I know now that the duct is supported by them but don't know what 'layer' it goes at. Radiator, washer, bushing, duct, bracket, bushing, washer, bolt?

[stevedmc]

Steve, do you have any pics of your duct installed?

Sorry, I don't have any pictures of it. Its pretty simple though. I removed/reinstalled my radiator without a brain or any documentation whatsoever. If I can do it anybody can.

Btw, get yourself some new bushings. Your bushings look pretty bad.

[jawn101]

Yup, new bushings also inbound. I dropped the rad once before to do the fans, so I know that's not hard - just wondering where the duct goes in the bushing sandwich :)

[DMCMW Dave]

Yup, new bushings also inbound. I dropped the rad once before to do the fans, so I know that's not hard - just wondering where the duct goes in the bushing sandwich :)

Install the radiator completely. The duct goes on last, the cutouts in the duct go around the lower rubber bushingf, and the duct gets tucked just above the metal bracket, so the metal bracket helps support the duct.

[jawn101]

Install the radiator completely. The duct goes on last, the cutouts in the duct go around the lower rubber bushingf, and the duct gets tucked just above the metal bracket, so the metal bracket helps support the duct.

So it should be doable without disconnecting and opening the cooling system then? Last time I supported the rad with some wire from above and a floor jack and 2x4 from below.

[Chris4099]

Correct. The radiator can be fully installed and bolted in place when the shroud goes in. As Dave mentioned, it's the last item to be installed.

[DCUK Martin]

As for the jacknut tool, I don't have one at all - just a standard riveter. Is this the sort of thing you mean, Martin?

http://www.harborfreight.com/45-piece-threaded-insert-riveter-kit-1210.html

Yes although I'm at a loss to explain the 45 pieces...

Jack nuts look like this

http://www.ebay.co.uk/itm/SCREW-ANCHOR-M6-SN-JACK-NUT-ANCHORS-QTY-20-/230669037641

[jawn101]

Yes although I'm at a loss to explain the 45 pieces...

Jack nuts look like this

http://www.ebay.co.uk/itm/SCREW-ANCHOR-M6-SN-JACK-NUT-ANCHORS-QTY-20-/230669037641

Ah, those are slightly different than what I have here. I got that kit (the 45 pieces comes from the 10 each of the 4 size nuts, plus 4 different heads, plus the handle)

The nuts it came with appear to be more like standard rivnuts. I verified that the largest of them is slightly larger than the ones I ripped out of the fiberglass, and I was able to do so with pretty clean holes. I was going to rivet/epoxy these threaded inserts into the hole and go from there. I didn't see jacknuts like the ones you linked to at any of the stores I checked over the last couple of days.

Sound reasonable? Or should I return this thing and seek out actual jacknuts somewhere?

[jawn101]

OK, I got proper jacknuts and installed them. The tool for those is much simpler and only cost 2 bucks. That threaded insert tool is going back, I won't need it given how easy these are to use and install. Now all that's left is to wait for my rad bushings and rock screen... tomorrow!

[jawn101]

OK, it's all in - but there was no conceivable way I could get the lower edge of the duct up underneath the radiator support brackets. Here are 2 pics of it installed. It looks pretty good now that it's in, but I do sort of wish I could have gotten it underneath. I wonder if the brackets could be bent - I might need to remove them again and straighten them out?

http://dmctalk.org/attachment.php?attachmentid=8713&d=1330660271

http://dmctalk.org/attachment.php?attachmentid=8714&d=1330660275

I did end up having to cut the top of the passenger side piece so it would fit. It was too tall and was jamming into the body tub.

New bushings look nice though... I can't believe how ruined the old ones were in comparison.

http://dmctalk.org/attachment.php?attachmentid=8715&d=1330660326

[vwdmc16]

Clutch!

[Farrar]

OK, I got proper jacknuts and installed them. The tool for those is much simpler and only cost 2 bucks.

Where you did you source these? This looks like the sort of thing I would need for my car's missing license plate nut.

Thanks,
Farrar

[Delorean Industries]

Where you did you source these? This looks like the sort of thing I would need for my car's missing license plate nut.

Thanks,
Farrar

Available from grainger or mcmaster. Not sure on pricing. I can't remember which without looking but one of the two companies require you to buy a complete kit just to get the installation tool. I could be wrong though....

[jawn101]

Where you did you source these? This looks like the sort of thing I would need for my car's missing license plate nut.

Thanks,
Farrar

I got them from my friendly neighborhood Ace hardware. Those guys have everything. Especially nice if you just need one or two of something and not a 50 pack from the big warehouses. Ace had the nuts in about 10 sizes as well as the installation tool. I think for the 2 large nuts I got plus the tool it was 4 bucks?

[Farrar]

I got them from my friendly neighborhood Ace hardware. Those guys have everything.

Excellent! Thanks. I will hit 'em up in the morning for those and some other bits and bobs.

You're not kidding about selection... my local Ace has lots of stainless hardware -- and in metric, too! -- and I like not having to buy more than I need.

[jawn101]

UPDATE: I removed the duct this afternoon as well as both lower radiator support brackets. They were clearly bent upwards. I bent them down to what appeared to be the right angle and reinstalled everything. The duct now fits far better and even looks pretty good.

I still think this is a part better suited for some sort of plastic, but results are results.