I have question for those with engine anylizers on their carburated Citabria's, JPI, EI, etc. I would like to know what temperature indications you get at high/full power settings, i.e. climb and high power cruise. I wont say what mine are at this time until I hear from a few other people. I'm very used to these guages as I use one in the 206 I fly. The 206 is injected with Gami's so this is apples and oranges to the carburated 0-320. I've talked to 3 differents AP's and naturally got 3 opinions. I've been told the Citabria has a lowsy cowling/shielding system and doesnt allow proper air flow to the engine. I will say at cruise settings, I get normal indications from the gauge.
Engine Analyzers
- Thread starter jeffidaho
- Start date
I would agree with you on the different temps! IIRC I will see EGT's from 1450 to 1350 and the EGT will be (these are approximates) 1- 320 2- 322 3- 352 4- 359. So yes, my #'s are way off probably like your #'s. I too am used to a Fuel Injected Cirrus with Gami's so this has been tough to get used to. I would like to get the spread closer so it would run more lean, but don't know how to fix it either?! 
I will right down my climb and cruise #'s and post them when I go out in a couple days and come back.
On another note, I spent the morning flying in Clear CAVU skys over Zions park and Bryce Canyon. Can't beat low and slow sight seeing!
I will right down my climb and cruise #'s and post them when I go out in a couple days and come back.On another note, I spent the morning flying in Clear CAVU skys over Zions park and Bryce Canyon. Can't beat low and slow sight seeing!
I'm really interested in your EGT's on 3 and 4. Thats where I'm noticing the big spread. My 3 and 4' go to 1550 plus/minus. While 1 and 2 will still be in the 1300's. Now this is only in power climb and max power cruise. When I bring the power back to 2400 rpm cruise or below all temps come together????
FYI-
What you are seeing is the typical poor fuel distribution of a carb. When you lean you are leaning to the leanest cylinder, the others will usually, always, be in a different state of lean/rich. On radials this problem was somewhat resolved by using an impeller to distribute the mixture, which is why it is so easy to supercharge radials, in horizontally opposed engines the only solution is injection.
Tom-
What you are seeing is the typical poor fuel distribution of a carb. When you lean you are leaning to the leanest cylinder, the others will usually, always, be in a different state of lean/rich. On radials this problem was somewhat resolved by using an impeller to distribute the mixture, which is why it is so easy to supercharge radials, in horizontally opposed engines the only solution is injection.
Tom-
What do you consider a max power climb/cruise? 2500 RPM at 25 inches MP? What is the fuel flow as well? Full Rich? Leaned? I've never seen any of my CHT's get over 1500 that I can recall. I climb keeping the mixture rich (1275-1325 EGT's). That keeps the CHT's under 360. Then I lean it in cruise to 8-9.5 gph which puts my EGT's around 1375-1450 depending on which cylinder I'm talking. That also keeps my CHT's around 290-325. I usually back off to 2300-2400 squared at that point because at 2500 squared in cruise, the plane wants to climb (to much power) and flies nose down and is at the yellow line in speed. Quite honestly, I usually fly around 1700-2100 squared at speeds in the 80-100 mph range since I use the plane for site seeing and goofing around only. I have a travel plane for real trips.
I had the heads flowed when I bought it which gives you about 10-20 more h.p. in most cases. The extra power is great for takeoff and climbing, but overkill for cruise. I flew the plane for 15 hours before having the heads flowed and doing so made it run smoother and actually brought my CHT's and EGT's a little closer together.
I had the heads flowed when I bought it which gives you about 10-20 more h.p. in most cases. The extra power is great for takeoff and climbing, but overkill for cruise. I flew the plane for 15 hours before having the heads flowed and doing so made it run smoother and actually brought my CHT's and EGT's a little closer together.
I dont have the fuel flow option on this plane, nor do I have MP guage, I got all that in the 206 and know all about the leaning/fuel/peak lean etc.
This is full power 2500 to 2700 rpm and full rich. My CHT's are all good or normal indications, but its the EGT's that I dont get.
This is full power 2500 to 2700 rpm and full rich. My CHT's are all good or normal indications, but its the EGT's that I dont get.
If you don't have all the gauges, I would recommend going full rich in the climb and then lean it to keep the EGT's around 1300 in the climb. Then lean it until it spudders a little in cruise and then add 1-2 knotches of fuel. That should be plenty LOP and should be around 9 gph at 25 squared which is well outside the damaging red box. If you don't understand the red box idea, check with the gami guys in Ada and go to their classes on LOP.
ok, I do have a EDM-700. It just does have the FF option. I very well experienced in all the rich of peak, lean of peak etc.
I just want to know if anyone else that has has one of these types of guages notices high egt's on cylinders 3 and 4 at full rich on full power take off and full power cruise.
Is there anyone else that can understand what I'm trying to say.
I just want to know if anyone else that has has one of these types of guages notices high egt's on cylinders 3 and 4 at full rich on full power take off and full power cruise.
Is there anyone else that can understand what I'm trying to say.
Jeff,
Yes, I do understand what you are saying and I have asked the same question. I have a 1966 7GCAA with a O-320 and a JPI-700.
I overhauled the engine about 1 1/2 years ago and then put in the JPI-700. I saw the same thing you are describing with the EGT's on 3 & 4. In addition, the CHT's for 3 & 4 will also climb over 400 degrees on climbout on a hot summer day here in Texas.
I posted a message on this board and nobody seemed to understand what I was asking, just like you. I also believe that the problem is poor fuel air distribution for this engine and not alot of consideration was made for good airflow over the cylinders.
Yes, I do understand what you are saying and I have asked the same question. I have a 1966 7GCAA with a O-320 and a JPI-700.
I overhauled the engine about 1 1/2 years ago and then put in the JPI-700. I saw the same thing you are describing with the EGT's on 3 & 4. In addition, the CHT's for 3 & 4 will also climb over 400 degrees on climbout on a hot summer day here in Texas.
I posted a message on this board and nobody seemed to understand what I was asking, just like you. I also believe that the problem is poor fuel air distribution for this engine and not alot of consideration was made for good airflow over the cylinders.
A bit off the thread above, but the topic still fits. I’m planning to swap the EI SR-8A for an EDM-700 with fuel flow on my 8KCAB and I’m wondering if anyone has added any additional sensors to their engine monitor (OAT, oil temp, RPM, etc)?
I’m interested in adding the oil temperature option and I’m wondering if I can just replace the existing probe installed at the oil screen or do I really need to use one of the alternate locations mentioned in JPIs install manual?
Thanks
Paul
I’m interested in adding the oil temperature option and I’m wondering if I can just replace the existing probe installed at the oil screen or do I really need to use one of the alternate locations mentioned in JPIs install manual?
Thanks
Paul