Back engine overheating on ground

Rickskymaster · #1 01-26-03, 03:58 AM

I had difficulity getting started this saturday. I got the back engine started right off, but the front just would not start. After 15-20 minutes, I finally got it going.
During the 15-20 minutes, I noticed that the back engines Oil temp was getting up there pretty high. My friend and I speculated that it was a problem with the Oil cooler, but as soon as we got the front started, the temps went down almost immediately.
Since, I am a new owner of a Skymaster, I am assuming that there was not enough cooling without the front engine running.
I should mention that as soon as we saw the temps go up, I repositioned the plane into a 10 knot wind, without any change. As soon as the engine fired up, boy did those temp go right down.
I will be interested in hearing all of your opinions.
thanks
Rick
N48AT

Paul Sharp · #2 01-26-03, 07:05 AM

I do think the front engine puts out a lot of cooling airflow to the rear. Whether that would explain it or not I don't know. Some others may have better input.

Don Hickman · #3 01-26-03, 10:35 AM

Yes, running only the rear engine will result in overheating. Taxiing on only the rear engine is not a good idea either. I had trouble starting my front engine a few weeks ago after getting the rear going and soon noticed that the rear oil temp was getting way too high. Fortunately, the front finally started and the rear temp came back down.

Bob Cook · #4 01-26-03, 12:07 PM

Concurr This is normal.

You need the front engine to supplement the cooling on the rear. If I taxi with one engine I will do it with the rear if the OAT is below 40 deg and then I watch ALL temps.

It is a tradeoff as you end up with FOD when taxing with the front at higher power levels (required with one engine taxi).

If there is a pileup for departure I always make a comment that if I do not get moving soon I will need to shut down the rear engine. Zoom-- to the head of the pack. Works every time (when needed).

fyi

Bob