Dashing through the prose, on a one Norse open dictionary, puzzling as he goes...

Þessi orð Ragnheiðar sýnast mönnum verit hafa af mikilli forspá, af þeim atburðum, er síðan gerðust með þeim Hrafni ok Þorvaldi. 

This word of Ragnheidar's seemed to people to have been of a great prophecy of the incidents which later came to pass between Hrafn and Thorvaldr.

Þorvaldr var með Hrafni nökkura vetr, ok eftir þat fýstist Þorvaldr at fara af landi. 

Thorvaldr stayed with Hrafn several winters, and after that Thorvaldr felt a desire to go from Iceland.

Þá fekk Hrafn Þorvaldi vöru nökkura, vistir ok vatnkeruld ok húðfat ok reykjuklæði ok alklæðnað ok tók honum fari á skipi þvi, er uppi stóð í Dögurðarnesi. 

Then Hrafn got Thorvaldr several wares, provisions and water-vessels and a hammock and bed-clothes and a full suit of clothes (I would really love to translate reykjuklæði as "smoking-clothes") and took him and asked for passage for him on that ship which was laid up ashore in Dogurdarness.     (CV rekkju-klæði, n. pl. bed-clothes)

Þórðr Snorrason átti bú gott ok gagnauðigt í Vatnsfirði, svá at hann var hvers manns gagn, þess er til sótti. 

Thordr Snorrason owned a good and well-stored farm in Vatnsfirth (Water-firth), so that he was what man's use, those who sought (him). (??)

En fyrir því at hallæri var á landi hér, þá fór Þórðr á várum til fiskjar með mikit skip ok húskarla sína í Bolungarvík, af því at hann þóttist þá fleirum mönnum gagn gera. 

But previously, because a famine was in the land here, then Thordr went in the spring fishing with a large ship and his men-servants in Bolungarvik, because it seamed to him then more men make use (= many hands make light work?).

Þat vár, er Þorvaldr var ráðinn til utanferðar, var Þórðr róinn á fiski, ok gerði at þeim vánt veðr, svá at þeir gátu nauðiliga land tekit. 

That spring, when Thorvaldr had planned for a journey abroad, Thordr was going fishing, and bad weather was granted them (they got bad weather), so that they were able to reach land with difficulty.       (similar to Z. fiski: róa fara til fiskjar, to go a-fishing)  (Also, I assume that nauðiliga is really  nauðuliga)

Þórðr var ern maðr ok kappsfullr ok liðgóðr at öllu. 

Thordr was a vigorous and eager-to-excel man and good at doing to all.

Ok er þeir kómu at landi, þá var Þórðr þreyttr af mæði ok þyrstr þeim munum meir en förunautar hans, sem hann hafði liðbetri verit ok miðr hlíft sér. 

And when they arrived on land, then Thordr was exhausted from distress and thirsty the minds (?) more than his crew, as he had been better-folk and less protection himself. (huh?)

Ok er hann kom at landi, þá drakk hann ór læk nökkurum, ok er hann hafði drukkit, þá kenndi hann sér sóttar, ok sú sótt leiddi hann til bana. 

And when he arrived on land, then he drank out of some stream, and when he had drunk, then he felt so sick, and that sickness let him to death.

Þórðr var mörgum mönnum harmdauði fyrir vinsældar sakir hans ok drengskapar. 

Thordr was to many men a sowerful death on account of his popularity and highmindedness.

Ok er Þorvaldr frá andlát Þórðar, þá seldi hann goðorð ok mannaforráð, þat er Þórðr hafði átt, í hendr Hrafni, meðan hann væri utan. 

And when Thorvadlr was informed of Thordar's death, then he handed over the authority of a goðorð and authority, that which Thordr had possessed, in Hrafn's hands, while he was out of the country.

Ok síðan fór hann í brott af landi ok var utan einn vetr. 

And then he went away from Iceland and was away one winter.

Ok er hann kom heim út hingat, kvángaðist hann ok fekk þeirar konu, er Kolfinna hét. 

And when he arrived home to Iceland, he married and got the woman who was named Kolfinna.    (Z. út 3: koma út hingat, or simply, koma út, to come to Iceland)

Hon var dóttir Einars Þorgilssonar ok Salbjargar Ketilsdóttur. 

She was the daughter of Einar Thorgilson and Salbjargar Ketilsdottr.

Ok síðan gerði hann bú í Vatnsfirði ok tók þá við goðorði sínu.

And then he built a farm in Vatnsfirth and then received his authority of godord.