Hot #3 cylinder CHT

[Hornet2008]

Hi All
My IO320 D1A has a hot #3 cylinder. Gets over 400F on climb, at about 1000'AGL. Trying to eliminate things and want to do a fuel flow to ensure the injectors are not running lean. First I will pull the plugs and check them. What should I be looking for colour wise? Have 5.5 hours on it. A new engine from Vans. I have already removed the dam at the front of #1 cylinder as that was getting hot (cooler now) and added the washer behind #3 between the baffle and the head.

[PerfTech]

Originally Posted by Hornet2008

Hi All
My IO320 D1A has a hot #3 cylinder. Gets over 400F on climb, at about 1000'AGL. Trying to eliminate things and want to do a fuel flow to ensure the injectors are not running lean. First I will pull the plugs and check them. What should I be looking for colour wise? Have 5.5 hours on it. A new engine from Vans. I have already removed the dam at the front of #1 cylinder as that was getting hot (cooler now) and added the washer behind #3 between the baffle and the head.

?.Swap the injectors, coldest to hottest and see if the problem
follows the injectors, or stays the same. Thanks, Allan..

[Raymo]

I had trouble with #4 on my first few flights with no gear fairings/wheel pants.

Since installing them, temps have come down significantly but I also worked hard at sealing the baffles and tuning the P-Mags to reduce advance shift.

[Hornet2008]

Hi, thanks for your replies. Standard mags, fairings fitted. Will try swapping injectors, see if that helps. I think I recently saw a plug colour/ cause chart on the forums or a reference to same but can't find it.

[Dbro172]

Make sure your baffle seals are sealing tight to the top cowl. If you are using vans standard material, with multiple joints, chances are they are not. Try installing McFarlane cowl saver material, using one single piece across the rear, and a single piece along each side. Formed to the top of the cowl...

[whd721]

What Dbro172 said,

Start with the cheap tests.

Get a flashlight and an inspection mirror and inspect every inch of your baffles. Shine the light on the engine side and inspect the outside of all each segment of the baffles. look for a light leak. Replace any baffle showing a leak. Look at the cowl for areas that don't show rub markings by the baffles and concentrate on those areas.

I had a hot #3 in my PA-140. Squawked it on several annuals. Finally, I decided to go back to basics and start a detailed baffle inspection. It is always difficult to inspect baffles due to limited access.

I found a leak at the rear baffle, repaired it and solved a long standing issue.

[whd721]

Part of my post got dropped.

The symptom of my engine was; #3 temp would increase in climb, however, once in cruise, #3 would fall back in line with the other cyls.

Good Luck!