engine compartment air blower for water cooled 2.1

[schoonerman]

Thinking of adding a air blower to blow air over the exhaust pipe area under the drivers side cylinder head, as I have noticed the cylinder head is always hotter than the passenger side.
I would mount a marine pipe fan with a flex pipe in the area where the outside vent air comes down. I would control it from a switch on the dash via the ignition switch.

Another idea would be to fasten a plate on top of the exhaust pipes to divert the heat away

Anybody done this, or any cons?

Thanks
Mike
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87 Westy/Vanagon

[Wildthings]

I have never noticed much difference in the heat from the two side, but I never really looked for such. When underway you are going to have many times the air flow over the pipes as you would get from a smallish fan. If there is an abnormal difference it would behoove you to find out why as it will likely lead to and engine failure down the road. Maybe all you need to do is add FI cleaner to your tank or have the injectors professionally cleaned. Leaky pipes might causes one side to be hotter than the others as well, leaky pipes will wreak havoc on your heads.

Properly rebuilt and maintained engines will run hundreds of thousands of miles without problems, no extra fans needed.

[schoonerman]

Thanks Wildthings,

I have a new re-built engine with stainless exhaust system and noticed a heck of a lot of heat from those pipes under the head, so stands to reason when in slow traffic heat will rise up to the head, another thought I had was that the oil filter and cooler are in the same area and any extra cooling in that are would extract heat from the oil filter/cooler etc.

Maybe I'm thinking too much?

Thanks
Mike
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87 Westy/Vanagon

[Terry Kay]

A bilge blower doesn't have enough cfm to cool down your pipes.
The pipes on all of these vans are hot.
Crawl under your car & grab the piped right off of the head.
You'll find it's really hot too.
No fan required.
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T.K.

[IdahoDoug]

There are always warmer and cooler areas of any engine simply having to do with where the coolant goes into the block, out of the block, the RPM you measure at, etc. When stationary there are again different areas of temps due to exhaust placement, presence of heat producing components, etc. These are all checked and measured during the design process and if pronounced hot spots are found, sometimes components will be moved here or there. But I would not chase an unequal temp issue like that with a fan, as it will likely have near zero effect on anything measurable in terms of longevity or fuel economy. However, it will add one more set of wires, an electrical draw, another source of a short, a component to fail, etc.

Perhaps just knowing that these temp differences are normal will help you sleep better without the modification? Dunno, but don't sweat it unless you are seeing something serious that indicates an operating problem.

DougM
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1987 2WD Wolfsburg Vanagon Weekender "Mango", two fully locked 80 Series LandCruisers. 2017 Subaru Outback boxer. 1990 Audi 90 Quattro 20V with rear locking differential, 1990 burgundy parts Vanagon. 1984 Porsche 944, 1988 Toyota Supra 5 speed targa, 2002 BMW 325iX, 1982 Toyota Sunrader

[Wildthings]

I have not idea what affect header wrap would have on SS pipes. That would certainly make them seem cooler, but at what cost?

[fraggle00]

Header wrap costs lifetime. How much, I'm not sure. I would maybe throw on a cheap motorcycle pipe heatshield if you're that worried and all the other systems check out. If all 4 pipes match temperature up near the exhaust port, I wouldn't worry about it. Use a digital temp gun.
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'91 Vanagon Carat
'87 Porsche 928S4 DOWN
'12 Fiat 500 Abarth

[schoonerman]

Thanks for the replies,

I took the van for a drive to get the temp up, about half an hour.

When I got back I let her idle and took the following measurements with temp gun.......

Drivers side head on top behind the valve cover....290F
Passengers side head on top behind valve cover....217F
Middle of engine near the seam..............................178F

Temp gun about a foot away
I took a few measurements and they were all in the same ballpark

My engine is a re-built 2.1 to a 2.2 with GW stainless exhaust system, 87F thermostat and a new radiator, with 3,000 miles since the rebuild

I would appreciate to hear what your measurements would be Guy's.
Thanks
Mike
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87 Westy/Vanagon

[vers13]

You actually want the exhaust to be as hot as possible, as this encourages the scavenging effect. By using a fan, this would be counter-productive. If you're really concerned about this (which I don't think you should), you could get a ceramic coat done on all of the exhaust pipes, although this requires you to pull the entire system. That will take care of the radiant heat coming from the pipes and actually should help in performance just a bit, not only by keeping the heat in the pipes, but reducing overall engine bay temps which also mean reduced intake air temp.

[spacecadet]

Or kevlar wrap them.. Which I tried out on my last engine rebuild, really because the WBXer supports this with our header style exhaust. I noticed a reduction in heat compared to before they were wrapped. I like the way it looks too.
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Daily Drivers Only
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1990 Volvo 740 Turbo(Sold)
1986 Mercedes 300 Coupe (Sold)
1954 Volvo PV544 (Sold)
1990 Dodge D250 Cummins (Totaled)
1990 Vanagon GL 2.1 Automatic (Sold)
1968 Ford F250(Current)