Transitioning to a Piper from a Cessna?

Cap'n Jack said:
Cessna 172s with fuel injected engines also have both the mechanical and boost pumps.
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While that's true, they are used differently. Cessna boost pumps are not used for takeoff and landing. They are used to prime the engine. For some cases (Cutlass RG, though that's not injected), it is used ONLY to clear vapor lock.
 
MAKG1 said:
While that's true, they are used differently. Cessna boost pumps are not used for takeoff and landing. They are used to prime the engine. For some cases (Cutlass RG, though that's not injected), it is used ONLY to clear vapor lock.
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On a FI engine the mechanical pump is required for the system to work. On Continentals system the boost pump has two settings, low and high. Low is used to prevent vapor lock at altitude and high is used to prime the engine and also as a redundant pump to keep the engine running should the mechanical pump fail.
 
My experience with Pipers is limited to a 1969 Arrow. Still a PA-28, but with FI. They fly very much the same way - throttle up to go faster, throttle back to go slower. That said, personally I am more comfortable in the Cessnas. There is something about the angle of the seat to the rudders (I think this is the cause) that causes my knees to die in about three hours. At that point it is all I can do to crawl out of the Arrow. I don't have this problem with a 172 or 182. YMMV.

Have fun, whatever you fly.
 
The 140 is a great little trainer, and a terrific starter-plane/time-builder. Have trained many students in both it and the 150 and find no major advantage or disadvantage to either other than the Pipers better preparing you for flying the majority of other types that require you to mind the fuel system (switching tanks, pump, etc.)
 
MAKG1 said:
Cessna boost pumps are not used for takeoff and landing. They are used to prime the engine. For some cases (Cutlass RG, though that's not injected), it is used ONLY to clear vapor lock.
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The carbureted C-172RG and C-177 both have full-time engine-driven fuel pumps, and electric aux pumps to be used if fuel pressure gets below certain values in flight.

With the Cardinal's low-slung wings, set further back on the fuselage, gravity alone might not supply enough pressure to get the fuel to the carburetor in very nose-high attitudes. The C-177 manual says,
"Fuel from each wing bay flows through a selector valve, small reservoir, and fuel shut-off to the fuel strainer. From here, it is routed to an engine-driven pump which delivers fuel under pressure to the carburetor. An electric auxiliary fuel pump parallels the engine-driven pump and is used when fuel pressure drops below 2 psi. [...] [G]ravity flow is considerably reduced at maximum performance take-off and climb attitudes, and the auxiliary fuel pump would be required if the engine-driven pump should fail during these maneuvers."​

My understanding of the need for the fuel pump in the C-172RG is that the presence of the nosewheel well forced a different carburetor arrangement, somewhat higher, than in the fixed-gear 172. Again, because of the different geometry, gravity might need help keeping the pressure high enough in some extreme attitudes, and the manual says turn the electric pump on if pressure dips below 0.5 psi.
 
The 172RG POH has no such language. The only place the boost pump is mentioned in normal operation is in warm weather engine start checklist, for the case where the engine is already warm. It is turned on, then off, during run-up to verify operation and is not turned on for any takeoff or climb procedure. It isn't even in the engine-out checklists.
 
MAKG1 said:
The 172RG POH has no such language.
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1983 C-172RG POH, page 7-25:
The auxiliary fuel pump switch is located on the left side of the switch and control panel and is a rocker-type switch. It is labeled AUX FUEL PUMP. [caps in original, sorry] When the pump is operating, it will maintain fuel pressure to the carburetor. It should be used whenever the indicated fuel pressure falls below 0.5 PSI, but is not required when gravity flow and/or the engine-driven fuel pump can maintain indicated pressures above 0.5 PSI.
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Henning said:
:confused: Where does Cessna move the carburetor on their O-320 Lycoming compared to the O-320 Lycoming on a Piper?
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I belive the carb is bolted to the sump on the Piper, providing a heat source from the sump making it more difficult to get an icing situation. The 172 has a manifold box that the carb bolts to which doesn't have the hot oil sitting next to it.
 
guardrail said:
I belive the carb is bolted to the sump on the Piper, providing a heat source from the sump making it more difficult to get an icing situation. The 172 has a manifold box that the carb bolts to which doesn't have the hot oil sitting next to it.
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I've heard that too.
 
guardrail said:
I belive the carb is bolted to the sump on the Piper, providing a heat source from the sump making it more difficult to get an icing situation. The 172 has a manifold box that the carb bolts to which doesn't have the hot oil sitting next to it.
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Thanks for clearing that up. I know they were different, but forgot exactly _how_ they were different.
 
guardrail said:
I belive the carb is bolted to the sump on the Piper, providing a heat source from the sump making it more difficult to get an icing situation. The 172 has a manifold box that the carb bolts to which doesn't have the hot oil sitting next to it.
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On the older Continental powered ones yes, on the Lycoming powered ones no, the carbs are on the sump.
 
Henning said:
On the older Continental powered ones yes, on the Lycoming powered ones no, the carbs are on the sump.
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Please, with your past record, post a reference.

All of the C172 POHs I can access, where a carbureted engine is used, have the carb heat on at low RPM and I suggest the OP follow the POH rather than what they find from forum postings.
 
Cap'n Jack said:
Please, with your past record, post a reference.

All of the C172 POHs I can access, where a carbureted engine is used, have the carb heat on at low RPM and I suggest the OP follow the POH rather than what they find from forum postings.
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Lol, look at the engines.
 

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Cap'n Jack said:
That's hardly a useful citation.

Attached image is what I got from your "reference". I know that one can buy stuff on line.

Again, to the OP, follow the POH rather than forum postings.
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I know you have some strange hard on for me, but that cite was to show you pictures of how the carburetor on the O-320 in the 172 is mounted directly to the engine sump, not on a manifold plenum like it is on the Continental O-300 on the earlier 172s. People can use or not use the carb heat as they see fit, I really don't care.

Edit: oh, I see the link didn't work correctly, let me try again...
 
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kenjr said:
All the important things other's have mentioned. I don't know why people complain about the crank so much - I learned to like it. The only thing I hate about it is the grasping around I do from time to time trying to find the crank. Otherwise it's very simple - Right for Raise, Left for Lower.
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Just pretend you're flying your Grumman Goose.
 
Here you go, try this:

image.jpg

BTW, please remove or resize the prior image as it blows out the entire page for anyone who is on an iPad.
 
Henning said:
I know you have some strange hard on for me, but that cite was to show you pictures of how the carburetor on the O-320 in the 172 is mounted directly to the engine sump, not on a manifold plenum like it is on the Continental O-300 on the earlier 172s. People can use or not use the carb heat as they see fit, I really don't care.

Edit: oh, I see the link didn't work correctly, let me try again...
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Hard-on? Nope, you're not an attractive girl.

I simply don't trust someone has a habit of posting false, misleading information, some of it very recently.

If one posts bad information, it's hard to trust them on anything, really.

See here for a recent example:
http://www.pilotsofamerica.com/forum/showthread.php?p=1284710#post1284710
 
Shepherd said:
Cessnas "float", Pipers don't.
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So, don't ditch in a Piper?

Float is virtually the same if the approach speeds are correct for conditions.

In my experience, the Pipers float more when landed hot, when compared at full flap, Cessnas with no flap.

I land both regularly at a 2400 foot field. While that's not terribly short, it does make me watch the float carefully, for every landing. It's a relatively long taxi if you miss the second turn-out....
 
Skylane81E said:
Granted this one is FI but the carb is in the same place on the carbureted planes
http://www.m0a.com/wordpress/wp-content/uploads/2009/01/lycoming-o-320-m0a.jpg
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Umm, FI's don't have carbs....that looks like a throttle body. I can't tell if it has a fuel connection in it or not, but the conventional place to put fuel in a mechanical injection system is at the intake ports (all of them), but it could be in the throttle body.

And the carbs are not all in the same place on every plane. The 172RGs have sidedraft carbs, not updraft. I believe they are on the back of the engine (not sure on that). The air filter is also impossible to inspect during preflight.
 
MAKG1 said:
Umm, FI's don't have carbs....that looks like a throttle body. I can't tell if it has a fuel connection in it or not, but the conventional place to put fuel in a mechanical injection system is at the intake ports (all of them), but it could be in the throttle body.

And the carbs are not all in the same place on every plane. The 172RGs have sidedraft carbs, not updraft. I believe they are on the back of the engine (not sure on that). The air filter is also impossible to inspect during preflight.
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The side draft carb is required due to the ENGINE having the intake port on the side of the sump. Cessna likely picked that engine for clearance to the wheel well but it is not a Cessna modification.

This one is indeed fuel injected, and as I stated the carb mounts to the exact same four studs if it is carbureted. I'm sorry I didn't take a picture of the 172N I had in the shop yesterday.
 
Skylane81E said:
The side draft carb is required due to the ENGINE having the intake port on the side of the sump. Cessna likely picked that engine for clearance to the wheel well but it is not a Cessna modification.

This one is indeed fuel injected, and as I stated the carb mounts to the exact same four studs if it is carbureted. I'm sorry I didn't take a picture of the 172N I had in the shop yesterday.
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The pic in post 60 comes off a 172N
 
Henning said:
The pic in post 60 comes off a 172N
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Yep, interestingly enough the TCM powered 172s even had the carb mounted to the sump

mUXX5EtLCTL11TiGLt3Oefg.jpg
 
Skylane81E said:
Yep, interestingly enough the TCM powered 172s even had the carb mounted to the sump
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So in theory, either both or neither should be subject to icing?

Still seems best to just follow the POH for the plane...
 
Cap'n Jack said:
So in theory, either both or neither should be subject to icing?

Still seems best to just follow the POH for the plane...
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Agreed, with one caveat.

My plane (known ice maker) has a carb temp gauge, rather than automatically pull heat I check the gauge first.
 
guardrail said:
I belive the carb is bolted to the sump on the Piper, providing a heat source from the sump making it more difficult to get an icing situation. The 172 has a manifold box that the carb bolts to which doesn't have the hot oil sitting next to it.
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That is correct ...bolted right on there and a $E&%RT^ to get on and off!
 
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