By John Kemp

LONDON, April 24 (Reuters) - Hedge funds have tempered their bullishness towards crude oil as the short-covering rally that gripped the market since the end of March ran its course.

Hedge funds and other money managers increased their net long position in the three major futures and options contracts linked to Brent and WTI by 8 million barrels in the week to April 18.

Fund managers have increased their net long position for three consecutive weeks by a total of 140 million barrels but the latest increase was much smaller than in the two previous weeks.

Funds showed little appetite to increase bullish long positions further, though they continued to close out bearish short positions established earlier in March.

Funds actually reduced long positions by 2 million barrels, though this was offset by a reduction in short positioning of 10 million barrels, according to an analysis of data published by regulators and exchanges.

The ratio of long to short positions climbed to 5.8:1 up from a recent low of 3.7 on March 28 though it was still well below the peak of 10.3 set back on Feb. 21.

The rally in oil prices between March 27 and April 12 was driven by short-covering as much as the establishment of fresh long positions.

But most of those short positions had been closed out by April 11 and certainly by April 18 limiting further upward price momentum.

By April 18, hedge funds had reduced short positions in NYMEX WTI to just 63 million barrels, down from a peak of 117 million barrels three weeks earlier.

The minimum hedge fund short positioning in NYMEX WTI over the last two years has been around 45-55 million barrels.

So with few short positions left to be covered, the rally in Brent and WTI prices ran out of steam around the middle of April.

Both flat prices and calendar spreads have been softening as the short-covering cycle is completed and amid growing doubts about whether OPEC's output cuts are draining crude oil stocks.

Brent calendar spreads for the second half of 2017 have been weakening more or less continuously since April 7 and flat prices for June have been falling steadily since April 11.

From the perspective of hedge fund positioning, the market now looks reasonably balanced, with few shorts left to squeeze, and fund managers running a large long position but not as stretched as earlier in the year.

(Editing by Susan Thomas) ((john.kemp@tr.com; +44 207 542 9726 and on twitter @JKempEnergy))