Skip to main content ↑ ↓
Topic: Sound insulation removal question (Read 832 times) previous topic - next topic

Sound insulation removal question

I have pulled off all of the sound insulation from the engine compartment that I could.  What was left was a thin layer of foam that is proving to be difficult to remove.  The glue appears to be impervious to Goo Gone.  Since it was attached to fiberglass I am afraid of using something like acetone or MEK.  Any suggestions?
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP

Re: Sound insulation removal question

Reply #1 –
Acetone and MEK have very differnt effects on Fiberglass.

MEK will clean most things from Fiberglass and will not harm the fiberglass, I always have it on hand and use it frequently ( it will even disolve silicon).

Acetone will disolve fiberglass and if used on gelcoat will cause the gelcoat to dull in just seconds. Do not use acetone for cleaning fiberglass, instead use it to soften fiberglass before doing a repair and the repair will never sesperate from the original fiberglass.
Wyatt
96 U320 40 WTFE, build 4943
84 Toyota Supra towd
2015 Jeep Wrangler towd
Victoria, BC, Canada

Re: Sound insulation removal question

Reply #2 –
Guys be careful with with any solvents. My experience has been different. Typically, MEK will soften and dull epoxy fiberglass. It is one of the most active solvents for epoxy. Acetone generally doesn't touch epoxy because it evaporates so fast it has no time to soften the resin. I have had less experience with Polyester fiberglass so I presume that is what Wyatt was talking about. However, MEK  is pretty strong stuff. Make sure to try any solvent on a non-critical area first.

I would also be very cautious due to the foam. The solvent could soak into the foam and retard the rate of evaporation and allow solvents to be much more active than the solvent by itself. You might want to try a heat gun first. I have had very good luck with the Rockwell Sonicrafter. It comes with a scraper blade that does miraculous things.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Sound insulation removal question

Reply #3 –
Thanks Kent, I guess I will stop drinking it
1993 U300, 6v92
build 4366
USAF retired, Flight Engineer, C124, C130
 ATP, A & E.  & ex AI

Re: Sound insulation removal question

Reply #4 –
Quote from: Bill Chaplin –
Thanks Kent, I guess I will stop drinking it

OK Bill, are you going to stop drinking the Acetone Cocktails, the MEK Highball or the Sonicrafter. I wouldn't give up drinking Sonicrafters for nuttin. It's no wonder you had so many Round Tuits on your hands.
The selected media item is not currently available.Kent Speers
Locust Grove, OK
1993 U300 SSE 40' (Restored at FOT 2009) Build 4323
720 watts Solar
6V92TA DDEC Silver Engine
2014 Subaru Outback

Re: Sound insulation removal question

Reply #5 –
You said engine compartment right (not generator)?  When I did mine there was no fiberglass - just wood and sheetmetal - and I have a '91 too (just different model).  I used a sander until I had a stable surface for new glue.
John Fitzgerald
1991 U300 (SAI) Side Aisle Island Bed 40'
Detroit 6V92 with Allison Retarder
Meridian (Boise), Idaho

Re: Sound insulation removal question

Reply #6 –
All I really could see was the pinkish looking adhesive, not what was underneath.  The bed was definitely wood so I started there.  I tried Goof Off and it seemed to work fairly well but evaporated very quickly because I had a large fan blowing air on me to keep the fumes down.  I then tried acetone with about the same result.  Next I tried the compartment that has the engine air filter where the side facing forward is fiberglass. I found that acetone did soften the surface but that just washing it with a brush was enough to remove the adhesive without damage.  Once the acetone dried the fiberglass surface was fine.  I then took a closer look at the area at the back of the engine compartment and discovered that it is also wood so I will be able to remove the adhesive before I sand it.
John Cooper
'91 GV 36'
Oshkosh chassis
Cat 3208T 300HP