Hello to all, im doing a few jobs on my boat and one of them is to put the write prop on it, as i can only get up to 2000 rpm, not 2400 rpm. im running on a perkins HT6 6354, my prop size at the moment is 21.15, and i think its to big....... and when i got the boat i was told that the prop was changed, so i dont have the write size, can anybody help me on this mater.......
The best bet is to go to a spacialist propellor service, give them the boat hull/engine/gearbox arrangement and they will tell you exactly what prop you should have and what surface ratio it should be. I used F A L in Buckie and they were superb. Does your engine achieve 2400rpm when not under load? if not you may have issues somewhere else, worth checking.
Sounds like you are on the right lines then. Just found the spec for my prop it is a 22 X 18 four bladed with a fairly high surface area ratio. I have a 280hp Ford Sabre and a ZF box (forget the ratio) I fitted a new one last year as the previous one had suffered de-zincification, cost about £800 but gives 16.5kt at 2300 maxed out. Since had the intercooler stack cleaned out so she should be good for 2500rpm again now though I must admit I haven't tried running above 2000rpm (12kt) this year. We normally cruise about 1400rpm 8kt as we do wild life cruises and people prefer a quieter ride.
FAL have a comprehensive data base of hull/engine/useage configurations, give them a try.
Their full name is F A L Propellor service tel 01542 832 185 enquiries@falpropellers.co.uk If I remember correctly the guy I spoke to was called Frank. He is considered THE propellor guru in this area and all the fishing boat skippers use him for supplying new props or re-pitching or dressing props. I am sur ethey will be able to help you.
Hi, Martin, Thanks for that email, i will give them a call and see what they can do for me, it would be nice to have the write prop size........... thanks again.
Hi, Martin, Well what can i say......Hmm, my propellor size should be 21,21 if i have a 2,1 gear box, but if i have a 1.5, 1 it should be a 21,16. so i had a look at my gear box and the plate that was on it box isnt there anymore so i dont know what gear box i have, but i dont think my boat would drive a 21,21 as it cant drive a 21,15......... so i dont know, hmm...... maybe i need a new turbo or fuel pump service....... it runs perfect, just cant get over 2000 rpm.
Sorry I have no real suggestions other than to try a diesel engineer. It could be like you said a turbo issue or something similar. Do you get black smoke at max revs or is it clean? any overheating?
Hi Pirate, Id be guessing but i seem to remember the HT6354 is approx 145hp... with that id imagine 10/11 ish knots and prop size about 21x15 with a 2-1 box, or 21x11 with a 1.5-1 box.. If the engine runs up to 2600 when out of gear it should be ok for 2400 in gear. Best to speak to a company like clements engineering for propeller estimates.. or see if you can find anyone close by with a prop u can try :) stu
Hi, Thanks for the replys........ when i get upto 18,2000 rpm it starts to get smokey, black smoke, its not over heating and air is on problem, its got the bigger intercooler, im mite try a turbo, if i do have 1.5-1 i need to drop a size, that mite help........ thanks so much for your reply.
