Engine Compartment Heat Shield
The aluminum heat reflective sheet that is glued to the engine "doghouse" insulation has separated and is laying on the top of the engine. It's in disrepair and I am going to replace it. What recom...
Forum Discussion
Hi,
I would recommend something that is under the doghouse, not on top of it. If the heat in the engine compartment is say 200F, and the insulation is below the doghouse, then the fiberglass doghouse is exposed more to the backside of the insulation and the 100F motorhome (or less) and the material that the doghouse is made of should stay below 100F.
However if the insulation is above the doghouse, the fiberglass can get really hot! Even if it is not transmitting much of that heat into the drivers area. Ideally, insulation on both sides is better, but you must have it on the engine side.
I replaced my buddy's doghouse insulation with some 1.5" thick air duct fiberglass insulation. The aluminized stuff he had installed caught fire on the road to Las Vegas, so we took it out completely, and drove on. When back home, we put a BBQ lighter to the duct insulation, it suffered no damage at about 700F, so put that on it. On his 1987 Class C, the exhaust is very close to the doghouse, and it was leaking near the engine to exhaust manifold connection (about 10" from the doghouse).
Fred.
I would recommend something that is under the doghouse, not on top of it. If the heat in the engine compartment is say 200F, and the insulation is below the doghouse, then the fiberglass doghouse is exposed more to the backside of the insulation and the 100F motorhome (or less) and the material that the doghouse is made of should stay below 100F.
However if the insulation is above the doghouse, the fiberglass can get really hot! Even if it is not transmitting much of that heat into the drivers area. Ideally, insulation on both sides is better, but you must have it on the engine side.
I replaced my buddy's doghouse insulation with some 1.5" thick air duct fiberglass insulation. The aluminized stuff he had installed caught fire on the road to Las Vegas, so we took it out completely, and drove on. When back home, we put a BBQ lighter to the duct insulation, it suffered no damage at about 700F, so put that on it. On his 1987 Class C, the exhaust is very close to the doghouse, and it was leaking near the engine to exhaust manifold connection (about 10" from the doghouse).
Fred.
