Turbo Cab gets new hood insulation!

Luis de Prat · 01-12-2008, 10:53 PM

Hey everyone, I finally got around to removing the old, crumbling hood insulation that came on my 951, removing the glue and fitting the new OE insulation pads.

Washed the car yesterday and followed the handy advice of using the vacuum at the car wash to remove all of the old insulation foam down to the glue:

Then came the hard part. Removing the glue! I cut open one of the bags the OE insulation panels came in and used that to cover the engine. This is a must, because the mess is considerable.

Doused the whole surface with WD-40 to soften up the adhesive, which is a good idea to protect the paint from scratches, but like I had feared, that was not going to be enough to get the glue off. Using a flat plastic kitchen spoon, it took some proper adhesive remover, scraping the surface and alternating with a citrus degreaser to get the gobs of glue off. It's pretty tedious and takes lots of elbow grease, as I expected.

The best way to do it is to work in sections. I started on one side and did half a panel at a time. I found the adhesive remover worked best applying it with a rag, then scraping with the plastic spoon, and then using paper towels with the degreaser to clean off the gobs of glue. I used a German adhesive remover called Mellecud, but I hear 3M makes a good product for this available in the U.S.

Here's the the clean surface:

The trickiest part, however, was fitting the adhesive pads with the hood on the car, since you only get one shot at it. Don't do this alone like I did. Get someone to help you. I made a small tear right above the washer tank, but the overall result is 100 times better than what I had before.

If you haven't done this yet or are putting it off, it really is worth it. I took my time and spent nearly 4 hours doing it but I'm quite satisfied with the result.

It's stated throughout the forum archives that you can do without the hood insulation because the factory did away with it on the late cars. Apparently, however, this was only the case on North American cars through 1989, as my 1991 RoW 951 came with insulation and I've seen other '91 cars with it as well.

I think you can probably do without it on a NA car, but I would definitely use hood insulation on a Turbo. Especially if it's red or a dark color. My 1990 S2 is US spec and came without it, however, over the years the paint on the hood has faded somewhat, while the paint on my 951 is still very thick and glossy. YMMV

flash968 · 01-13-2008, 07:09 AM

definitely looks cleaner

have you measured and compared under hood temps yet? any improvement? how about sound?

jcommin · jcommin's Garage

Nice job. I want to do that to mine this spring. I got the insulation pads. I guess I plan for a doing the job on a Saturday. Thanks for the post.

Luis de Prat · 01-13-2008, 09:47 AM

Quote:

Originally Posted by flash968

definitely looks cleaner

have you measured and compared under hood temps yet? any improvement? how about sound?

Practically all of the previous insulation was intact, so I don't expect any temperature change.

I replaced it because it would crumble to the touch and shed "brown dust" into the engine compartment.

flash968 · 01-13-2008, 11:55 AM

ah - hmmm - the 968 never came with it, and i have been working a lot on the under hood aerodynamics and heat management, with quite a bit of improvement so far - i was just wondering how effective/ineffective it was at doing anything for heat or sound

Luis de Prat · 01-14-2008, 01:05 AM

Quote:

Originally Posted by flash968

ah - hmmm - the 968 never came with it, and i have been working a lot on the under hood aerodynamics and heat management, with quite a bit of improvement so far - i was just wondering how effective/ineffective it was at doing anything for heat or sound

Well, FWIW we were comparing cars with a 968 owner yesterday and noticed the underside of his hood had begun to develop a few bubbles in the paint on the exhaust side. OTOH mine was good as new when I managed to get all the old glue off.

flash968 · 01-14-2008, 05:05 AM

wow - that's the first time i've ever heard of that - that would make that stuff a plus at least for that reason

Aufgeladen944 · 01-14-2008, 06:19 PM

Could have skipped removing the old glue? Think that would make an enormous difference?

Wonderful looking car, by the way. I'm quite jealous. In a few years, I might pick up a 944S2 cabrio, and I hope it looks as good as yours does.

Luis de Prat · 01-15-2008, 02:06 AM

Quote:

Originally Posted by Aufgeladen944

Could have skipped removing the old glue? Think that would make an enormous difference?

Probably not. Just wanted to make it easier if I ever have to do it again.

Thanks for the compliments. I really enjoy the cabs!

CJFusco · CJFusco's Garage

I hate the hood insulation.

On my old 944, I removed all of it off my hood because I was so sick of the extra effort to keep my engine bay clean. This was a good 6 years ago or so. When I sold the car last year, there was no sign of any damage from the increased temps... but then a turbo would run a lot hotter than a NA...