Originally Posted by
MrDig
At present I prime the line up to pressure, this takes about 8 pumps before correct line pressure. Then prime the cylinders 4 pumps, swing the prop several times and another 4 primes
From the Yak-52 perspective, this sounds wrong. First prime the cylinders - primer to the right - ideally one prime for every ten degrees below CHT 100C (but don't prime above 80C, and I find not required above 40C if run recently), with someone pulling a blade through between strokes on the primer. When very cold ambient conditions, leave for 90 seconds to allow the fuel to vapourise slightly - then immediately before starting, throttle open about an inch, primer to the left, pressurise the lines, then back to the right, engage the starter, as it catches mags on, and if cold encourage it with some additional strokes on the cylinder primer. I'd guess if you're pressurising the lines and *then* the cylinders, you're losing the pressure in the lines. I defer turning on the air until the manual manipulation of the prop has been completed.
Pulling the blades through 30 times is overkill - a dozen blades will either clear any oil that
can be cleared by pulling through, or, by resistance, tell you if you have a hydraulic lock. If you don't have it already, consider having an inlet manifold drain fitted - standard Russian practice (without the drain) required removing the cowls and manually draining the inlet manifolds if the aircraft has been standing for more than a few days, since pulling the prop through isn't effective in removing oil in this area - the addition of the drain, and leaving the aircraft with the drain open, stops oil pooling in the inlet manifolds.
The other top tip I learned recently about 18Ts is not to park on a slope somewhere in the inner Hebrides with the right wing down, since this can apparently allow the priming system to dry out, which can only be fixed with the help of a Nanchang, a Cherokee 6 and a hell of a lot of avgas.....
Edited: to stop the OP rushing out and performing 10 times the required amount of priming...