Hood blanket... literally? (engine compartment thermal insulation)

[Ford Man]

Originally Posted by Christ

Ford Man - I find it amusing that both of your fuel logs show close to the same mileage per gallon, yet based on your percentages above EPA rating, obviously the older car had a higher efficiency rating...

The '97 is also about 85-90% highway driving and the '88 is combined city/rural road driving.

[Christ]

Does the full engine blanky work for the summer time too? I wonder... It'd probably be one of those things that you don't leave on all the time, rather you have to take it off for the hotter part of the year.

[Christ]

Originally Posted by Ford Man

The '97 is also about 85-90% highway driving and the '88 is combined city/rural road driving.

The idea of that post was to say that "obviously" the older car had a higher efficiency rating than the newer one.

Thank you for the insight though.

[FastPlastic]

My day involves rather short trips through out the day anywhere from 1-5 hours apart. Now that it's cold (lows in the 20's so far) my jeep looses it's heat rather quickly so even when it warms up completely over about 3-4 hours it's like a cold start. When doesn't have time to warm up completely if I wait too long it ends up a cold start as well.

So, my Jeep doesn't have any insulation under the hood so I was thinking about adding some. Any recommendations on what I should get? Anything out there that is cheap?

Also I remember over last winter the snow melts rather quickly around the edges of the hood. I know for a fact it doesn't have trim around the hood edges. Would adding some help hold the heat in for a little longer?

I've already blocked off most of the grill. Which helps warm it up a lot faster. But I think keeping the heat in would help to get it back to normal operating temp faster.

[MetroMPG]

Hi FastPlastic - there's a live thread on this topic going on. Hope you don't mind I merged your post in here.

[almightybmw]

ya know I never used a blanket like that in the winter back in alaska, but I think I should have.

[FastPlastic]

So last night I was watching my temps. one of my trips got the engine up to 161F. I got back to the Jeep an hour and a half later and it had dropped to 79F. The ambient temp was 17F. Which is still higher then we see most of the time at night.

So I decided I'm gonna give it a shot and see what happens. I picked up some 3/4" wide by 1/2" thick foam weather stripping at Wal-Mart. It was only $2.75 for 10 feet so I figure it's no big loss if it doesn't work.

My goal is to make a reverse chest freezer like you see at the supermarket. The ones with the open top. The reason they work is because cold air sinks to the floor. So I'm going to try and seal up the top of the engine compartment to hold the heat in since hot air rises. I already have most of the grill blocked off especially across the top. So now all I need to do is seal things up.

[Christ]

Originally Posted by FastPlastic

So last night I was watching my temps. one of my trips got the engine up to 161F. I got back to the Jeep an hour and a half later and it had dropped to 79F. The ambient temp was 17F. Which is still higher then we see most of the time at night.

So I decided I'm gonna give it a shot and see what happens. I picked up some 3/4" wide by 1/2" thick foam weather stripping at Wal-Mart. It was only $2.75 for 10 feet so I figure it's no big loss if it doesn't work.

My goal is to make a reverse chest freezer like you see at the supermarket. The ones with the open top. The reason they work is because cold air sinks to the floor. So I'm going to try and seal up the top of the engine compartment to hold the heat in since hot air rises. I already have most of the grill blocked off especially across the top. So now all I need to do is seal things up.

Looking forward to an update on that... wanna see how it works out for you.

I was thinking about getting some sheet and making an undertray for my front end... then I noticed I was about a quart low on oil... so I have to trace ANOTHER oil leak. Hell, I might even be burning it by now, since I've been beating on this engine since it was built, about 30k ago (I think.. it's been 2 years... maybe it's 50k by now)

[93Cobra#2771]

Originally Posted by 93Cobra#2771

The underhood insulation is there for a sound deterrent. Any heat retention is incidental. If it was important to keep it warm under the hood, they would seal it up just like the passenger compartment. Rubber seam sealed and all.

A much better way to retain heat would be to pop the hood and put said blanket on top of the motor, avoiding any hot exhaust parts of course (don't want to burn the car down).

To answer the OP question - waste of time to try to add additional hood insulation.

Originally Posted by Christ

Cobra - When you say that heat retention is not necessary, you fail to logically understand the concern of the OP.

His concern was the if you warm the engine, it's more efficient than a cold one. Thus, keeping the underhood area warm will obviously keep the engine warmer, and it will run more efficiently from the first minute of the next start. He's not talking about retaining heat for hours, or days, but minutes. maybe an hour.

by the way, if you have read anything on this forum about efficiency, you would know already that heat retention is key in making an engine more efficient.. this "the OEM didn't do it, so it won't work" mentality is BS. It shows a considerable lack of evaluation skills. If that was the mentality of the rest of the world, we would not have most of the things that we have.

Please think twice before poisoning the board with this type of information.

Perhaps if you had read my post a little more carefully, you would have noticed I was referring to hood insulation ON THE HOOD itself. My point was with all the gaps and places for the heat to make it's way out, it wouldn't be an effective way of keeping heat in the motor. Perhaps, when I said "If it was important to keep it warm under the hood, they would seal it up just like the passenger compartment. Rubber seam sealed and all." I should have said "If it was important to keep it warm under the hood, they would seal it up just like the passenger compartment. Rubber seam sealed and all. But there is a better way to keep the engine warm.". In fact, I'll give you that point, as I typed my original post on a phone, which can make it a little difficult to keep track of what you type and don't type.

I NEVER in any part of my post said that heat retention was not necessary. I quoted my original post just so you wouldn't have to scroll back and look.

Then I gave the option of insulating the top of the motor itself with some type of blanket placed on it, which would be MUCH MORE effective at keeping heat in the motor.

The engine blanket that silverinsight2 showed in his thread is exactly what I was talking about.

Please think twice before accusing people of "poisoning this board" and actually read and evaluate someone's post before spouting off on a diatribe and lecturing everyone on how they should and should not participate in threads. That's the whole point of a forum, to get feedback from people with multiple backgrounds and ideas about different things and ways they might or might not work better.

By the way, there is a much better alternative to Dynamat, at a fraction of the cost. It is called "Peel and Seal" and is located at Lowes and Home Depot in the roofing section. It is a super adhesive product, about 1/4" thick, used to seal gaps in roofing. It has a reflective aluminum laminated to one side and is identical to Dynamat (I have used both). I insulated the entire roof and floor in my escort, primarily for sound deadening purposes. An added bonus is it keeps it from getting near as hot inside in the summertime while baking in a parking lot. And it is MUCH less expensive than dynamat.

Peel & Seal at Lowe's: 6"x25' Roll Self-Stick Aluminum Faced

[Christ]

Originally Posted by 93Cobra#2771

Perhaps if you had read my post a little more carefully, you would have noticed I was referring to hood insulation ON THE HOOD itself. My point was with all the gaps and places for the heat to make it's way out, it wouldn't be an effective way of keeping heat in the motor. Perhaps, when I said "If it was important to keep it warm under the hood, they would seal it up just like the passenger compartment. Rubber seam sealed and all." I should have said "If it was important to keep it warm under the hood, they would seal it up just like the passenger compartment. Rubber seam sealed and all. But there is a better way to keep the engine warm.". In fact, I'll give you that point, as I typed my original post on a phone, which can make it a little difficult to keep track of what you type and don't type.

I NEVER in any part of my post said that heat retention was not necessary. I quoted my original post just so you wouldn't have to scroll back and look.

Then I gave the option of insulating the top of the motor itself with some type of blanket placed on it, which would be MUCH MORE effective at keeping heat in the motor.

The engine blanket that silverinsight2 showed in his thread is exactly what I was talking about.

Please think twice before accusing people of "poisoning this board" and actually read and evaluate someone's post before spouting off on a diatribe and lecturing everyone on how they should and should not participate in threads. That's the whole point of a forum, to get feedback from people with multiple backgrounds and ideas about different things and ways they might or might not work better.

By the way, there is a much better alternative to Dynamat, at a fraction of the cost. It is called "Peel and Seal" and is located at Lowes and Home Depot in the roofing section. It is a super adhesive product, about 1/4" thick, used to seal gaps in roofing. It has a reflective aluminum laminated to one side and is identical to Dynamat (I have used both). I insulated the entire roof and floor in my escort, primarily for sound deadening purposes. An added bonus is it keeps it from getting near as hot inside in the summertime while baking in a parking lot. And it is MUCH less expensive than dynamat.

Peel & Seal at Lowe's: 6"x25' Roll Self-Stick Aluminum Faced

I have to apologize for that one, apparently, I missed the engine blanky part... I don't remember reading it the first time through, so I may have been quick to the shot on that one.

I was generalizing when making comments about how people on this (and other) forums tend to have a propensity toward saying things like "if the OEM didn't make it that way, it won't work", which is obviously BS, as you and most of us here well know. These statements tend to be discouraging.. and usually the only part of a post that people remember for a long time.

I actually know about peel and seal, primarily because I've used it for its intended purpose. I'm a construction worker by trade. Not by choice, but it pays $18/hour when I'm actually working.. (winter layoffs)