Purchased and installed a DLE 30 in my GP Super Stearman.....broken in on test bench per instructions with no issues. During maiden flight engine quit during straight and level flight....about four laps around field. Landed checked fuel, fittings, battery, engine heat...all normal. Added fuel re started, ran through pre flight, took off and engine dead sticked in exactly same place. Landed re checked airplane, re started ran at 3/4 throttle engine started loosing rpms after 5 minutes and then died. Re started (immediately) very easy....ran at full throttle for five minutes started losing rpms and died.

Outside temp was 45 degrees cowl has plenty of in and out air flow. Engine is mounted inverted with JTech Pitts style muffler. Engine is sometimes hard to start after sitting for a few days...does not want to draw gas into carb. I have pressure checked gas tank, fittings and all are ok. Any ideas or suggestions?
Thanks in advance !<br type="_moz" />

did you happen to pull the spark plug to see if there was an color issues, assuming you did not have one of the spark plugs that was not of the better quality upon receiving the engine.

Have you had a chance to make sure for some odd reason you do not have screen debris in the carb?

No mention of setting the needles in the airplane. Did you do that after installation? From your description, the engine sounds lean. How about cooling airflow through the cowl and engine fins? Is that adequate?

How about the plug ... have you replaced the supplied DLE plug with a proven NGK CM-6?

Fuel tank venting ?

As in , If the tank isn't vented properly , the engine will run till the tank has so much vacuum that the pump can't overcome it , and then it quits .

About five min. run time till the pump can't overcome the vacuum of the improperly vented tank sounds about right ...........

about as good a guess as I can come up with too!

How about giving us a vivid description of your fuel system setup from the clunk to the carb . and pictures could be helpful.
A few things come to mind but without more details on what you have it would be too much speculation.

Thanks...will try to post pics tomorrow.

I have a DLE 30 in a Stearman as well and it required a 1/8 turn richer on the low needle when the cowl went on. Not a problem with no idling before takeoff but noticed after idling at edge of runway one time waiting for someone to land it heated up a bit and began hesitating. The 1/8 turn did the trick.

rich the high needle 1/4 turn it will work fine

ilan

Thanks....I will give it a try

Replaced plug with NGK CM-6, 1/4 turn rich on the high needle. Working perfect....thanks!!

Yipee ..... YAK-54 in post #9 wins the prize!!

Seriously though, thanks for coming back and posting your findings.