#1 Rear Still Hot

[kilr4d]

Originally Posted by tomcomet

Up here in Canada I am flying around in 0 to -20C and even then I am breaking 400 degrees on #1 rear often and have to crack open the rear cowl flaps. Not normal and not great!

Your rear engine is a completely different story and imho it isn't an airflow issue.

The rear engine (except for cyl#1) is way happier than the front....higher fuel flow, gentler CHT rise, consistently cooler temps, etc. From what I see the #1 cylinder is an isolated issue.

Action items:

1. Check fuel flows as per TCM SID using calibrated gauges.
2. Check timing using a digital angle finder, not the old buzz box.
3. Talk to GAMI about the #1 cylinder...confirm correct injector shipped and installed in correct cylinder.
4. Fly and record an LOP mag test. A bad plug or wire can cause high CHT's.
5. Clean injector and confirm flow from fuel injector block.
6. Check for vacuum leak in intake manifold to cylinder.
7. I hate to say it but also borescope the #1 cylinder just to make sure cylinder walls and valves look ok.
8. Let's park ours sided by side, decowl and compare baffle seals.