Quad CHT Gauge?

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BlissfullyCrusin
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Quad CHT Gauge?

Post by BlissfullyCrusin » Fri Dec 08, 2006 12:03 pm

I apologize if this is the wrong forum for this message, but I'm pretty sure it belongs here.

I've been debating buying a QUAD cht gauge and was wondering if anyone here had any experience with em? I've never understood the reasoning behind having just a single cht gauge. Yes, chances are #3 is more likely to fail due to restricted airflow but who's to say the others wont fail as well?

For those curious, the beast of which I speak can be found here:
http://www.aircraftspruce.com/catalog/i ... quads2.php

Thoughts? Comments?

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Amskeptic
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Re: Quad CHT Gauge?

Post by Amskeptic » Fri Dec 08, 2006 12:13 pm

BlissfullyCrusin wrote: I've been debating buying a QUAD cht gauge and was wondering if anyone here had any experience with em?
Yes, chances are #3 is more likely to fail due to restricted airflow but who's to say the others wont fail as well?
A quad is optimal. Go for it. #2 is the problem cylinder with Type 4 engines.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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satchmo
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Post by satchmo » Fri Dec 08, 2006 12:38 pm

I had CHT gauges on #1 and #3 for quite a while. #3 ALWAYS ran hotter than #1, so I got rid of the #1 gauge.

But I agree, monitoring all four cylinders is optimal.

Tim
By three methods we may learn wisdom:
First, by reflection, which is noblest;
second, by immitation, which is easiest;
and third, by experience, which is bitterest. -Confucius

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Sluggo
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Post by Sluggo » Fri Dec 08, 2006 7:06 pm

That exact gauge has been on my list for a while. When I make my custom gauge cluster.
:vwgauge420:

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covelo
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Re: Quad CHT Gauge?

Post by covelo » Sat Dec 09, 2006 1:33 pm

Amskeptic wrote:Go for it. #2 is the problem cylinder with Type 4 engines.
Why is this? When I adjusted my valves after the Death Valley trip I thought I had the engine turned the wrong way at first, because there was hardly any clearance at all on Number 2. :pale:
‘80 Vanagon Westfalia - 54,400 miles
'91 Toyota Pickup (4WD long bed) - 199,960 miles
1987 Alfa Spider Veloce - 166,400 miles
2017 VW E-Golf - 5,600 miles

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Amskeptic
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Re: Quad CHT Gauge?

Post by Amskeptic » Sat Dec 09, 2006 2:24 pm

covelo wrote:
Amskeptic wrote:Go for it. #2 is the problem cylinder with Type 4 engines.
Why is this? When I adjusted my valves after the Death Valley trip I thought I had the engine turned the wrong way at first, because there was hardly any clearance at all on Number 2. :pale:
More evidence still, huh?

My guess is this:
The air comes blasting out of the fan housing outlet and pretty much shoots over to the underside of the cylinder cover at #1. Like standing under a waterfall and finding yourself pretty dry, #2 is actually getting robbed of air. As important is the fact that #2 connecting rod journal is at the end of the connecting rod bearing oil path. Connecting rods get their oil from the crankshaft galleries. #2 gets its oil from the gallery feeding the #3 and #4 main bearings. #2 piston is always the first one to seize during a lubrication failure event. I strongly recommend that we all notch our connecting rods to help the cool the undersides of the pistons, particularly with 2.0s (it is harder to control the expansion rate of the pistons/cast-iron cylinders of the larger engines)
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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covelo
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Re: Quad CHT Gauge?

Post by covelo » Sun Dec 10, 2006 12:50 pm

Amskeptic wrote:I strongly recommend that we all notch our rods
Is there anything less drastic that can be done? Should I set my #2 clearances at .007 next time before a long hot trip? Break down and get a CHT gauge?
‘80 Vanagon Westfalia - 54,400 miles
'91 Toyota Pickup (4WD long bed) - 199,960 miles
1987 Alfa Spider Veloce - 166,400 miles
2017 VW E-Golf - 5,600 miles

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Amskeptic
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Re: Quad CHT Gauge?

Post by Amskeptic » Sun Dec 10, 2006 9:19 pm

[quote="covelo
Should I set my #2 clearances at .007 next time before a long hot trip? Break down and get a CHT gauge?[/quote]

Clean, well-tuned < ! keep revs up when working it up the grades, adjust your valves in a timely fashion, and you will do fine. NO LEAK-INDUCED LEAN MIXTURES.
Colin
(consistent .007" is getting in "hammer-the-valvetrain" territory)
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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