• PiperForum.com is a vibrant community of Piper owners and pilots. Our over 1,500+ active members use Piper Forum to swap technical knowledge, plan meetups and sell planes/parts. We host technical knowledge of general aviation topics and specific topics on J3-Cubs, Cherokees, Comanches, Pacers and more. In addition to an instant community of pilots for you, PiperForum.com is a library of technical topics, airplane builds, images, technical manuals, technical documents and more.

    Access to PiperForum.com is subscription based. Subscriptions are only $49.99/year or $6.99/month to gain access to this great community and unmatched library of Piper knowledge.

    Click Here to Become a Subscribing Member and Access PiperForum.com in Full!

Cherokee 140 - 2150 static RPMs and poor climb out... high DA or engine/carb issue?

This site may earn a commission from merchant affiliate links, including eBay, Amazon, and others.
Dec 22, 2021
Reaction score
Hi all,

Hoping you guys can ease my mind or point me in the right direction.

The other day I took a friend and his 7 yr old daughter for a flight. It was hot and very humid with 3000ft density altitude (30 gal of fuel), I'm 170, he's 185 & she's 50lbs. Runup was normal and mag drops were good (just completed annual and had mags overhauled... also carb was OH last November). Engine instruments were in the green, however I noticed taking a little longer than usual take off roll and we were not climbing as fast as I'm used to. I checked my airspeed - it was ok, RPMs were a little low 2200-2250 ish, but then looked at VSI and it was only around 100! In hind sight probably should have aborted... but by the time I realized that things were off and there was a problem, landing wasn't an option with trees and a river at the departure end. Airspeed increased so I traded that for altitude and climbed out at 200 to 300 ft/ min. Was probably the scariest experiences I've had on TO.

I'm trying to determine if it was indeed just a hot/humid issue and I'm not used to that or something internal could be going on with the engine. I've flown with my whole family (wife, 145lb son, 45lb daughter) before - though not in the summer. I have the Lycoming o-320 E2A 150 hp engine, 1967 cherokee 140. My test static run ups are yielding 2150 RPMs, but I can lean and get another 50 (+-). Climb out is usually around 200ft/min, then improves to 400 as I reach TPA. I believe the AFM states minimum static should be 2275... but isn't that at sea level on a standard day? So could it just be DA? These planes drive me nuts sometimes! lol

> Compressions are good 70, 74, 76, 78
> Mag timing is "dead on" per A&P
> I have a climb prop.

Thanks in advance for your advice/suggestions.

Also - I should mention, one A&P says I should adjust the "stop" on my throttle to increase power. Another says, it's a mixture issue and I need to lean the mixture adjustment screw. I'm hesitant to have anyone fiddle with the carb since it was just OH by a shop I've heard nothing but rave reviews on.

Thanks again!

Latest posts