takeoff roll hesitation at 2000 rpm

GeorgeC

GeorgeC

Administrator
Management Council Member
Joined
Dec 5, 2010
Messages
5,503
Display Name
Display name:
GeorgeC
On the takeoff roll, my O-200 will sag for a moment as it accelerates through around 2000 rpm, then it catches up with itself and is fine. I don't remember it doing this before.
 
I've seen that due to a loose carb bowl on my O-320.
 
Heard of similar problems, 2 different local O-200's, due to issues with the air filter element (Brackett I believe), solved by return to dry paper filter. I know the Bracketts are supposed to be better, and have a good reputation, maybe they were simply gummed up with too much oil and dead bugs or such, not sure. Nobody really had a good explanation, but the problem was fixed. Might be worth investigating that avenue. If I see either of those operators this weekend, I'll try to get more details.
(I hate when "magical" procedures actually solve glitches for no apparent reason, but sometimes it just works that way!)
 
Last edited:
I have posted this advice four or five times over the last eleven years:

The O-200's carb is mounted to a carb "spider," a small manifold with four outlets. There are supposed to be Lock-O-Seal washers against the top and bottom of that spider on both studs, and the retaining nuts tightened FINGER TIGHT and cotter pinned. This lets the engine move without shaking the carb so much. Shaking causes fuel to slop from the carb bowl into the carb throat thru the bowl vent and makes for rough running and big rpm drops. We chased that issue for weeks on one 150 until I found that little paragraph in the overhaul manual. Installed the washers and it all cleared up.

And read this thread: https://www.pilotsofamerica.com/com...tent-loss-of-engine-power.70561/#post-1454186
 
Thanks. I would have hoped an engine shop would have gotten that detail right, but I guess you never know.
 
GeorgeC said:
Thanks. I would have hoped an engine shop would have gotten that detail right, but I guess you never know.
Click to expand...
Found them wrong right out of the rebuilder.
 
Dan Thomas said:
I have posted this advice four or five times over the last eleven years:

The O-200's carb is mounted to a carb "spider," a small manifold with four outlets. There are supposed to be Lock-O-Seal washers against the top and bottom of that spider on both studs, and the retaining nuts tightened FINGER TIGHT and cotter pinned. This lets the engine move without shaking the carb so much. Shaking causes fuel to slop from the carb bowl into the carb throat thru the bowl vent and makes for rough running and big rpm drops. We chased that issue for weeks on one 150 until I found that little paragraph in the overhaul manual. Installed the washers and it all cleared up.

And read this thread: https://www.pilotsofamerica.com/com...tent-loss-of-engine-power.70561/#post-1454186
Click to expand...
Somewhere this should be a sticky for O-200 owners - probably on the type club if it's not already. I've experienced the infamous engine stumble, once it was immediately following maintenance. Another time the power rolled back briefly turning base to downwind, the mechanic who'd just signed it off from annual blamed Champion spark plugs. Unfortunately I don't know if he ever checked for the presence of lock-O-seals.
 
Does the 0-200 have an accelerator pump? Her lil cousin the c85 does not, and in cold Wx especially if ya do not operate the throttle smoothly on the way to the firewall she will stumble... but i think youndo have the accelerator pump..
 
Huckster79 said:
Does the 0-200 have an accelerator pump? Her lil cousin the c85 does not, and in cold Wx especially if ya do not operate the throttle smoothly on the way to the firewall she will stumble... but i think youndo have the accelerator pump..
Click to expand...
It has the pump.
 
At annual, I asked that they ensure the manifold was installed IAW the O200 o/h manual; they said it checked good. They also said they flushed some water and crud out of the carb. There was no hesitation on the takeoff roll today.
 
You must log in or register to reply here.
Back
Top