Trim tabs

[Gypsymagic]

Any comments on the use or need of trim tabs on a GB 42C?

Trying to decide if I should remove mine as they have not worked since I bought the boat. I’m a single Cat 3208 375 hp and even at WO I can achieve not more the 12 knots.

 

[Papas]

On my 46 w/ twins, the tabs work just fine, but that doesn't mean they are effective. At WOT, trimming bow down may gain an additional 1/4 - 1/2 knot, but going from 3gph / side at normal cruise to 16+gph/side means they are almost always left in a neutral position (as normal cruise vs. WOT is all of about a 2 knot difference). I've absolutely considered removing them so I have one less system to have to maintain. IMHO, you don't need TT's on a semi-displacement boat like the GB (unless you have twin 475 beasts).

 

[JohnP]

I have removed mine. Only rarely used them. They were hard for me to keep clean, guess I never got the primer right to keep the paint on. Only once reached 14 knots. Light on fuel, water, and stores, not the way I like it. Happy to cruise- 7 to 8 knots, no need to plane. At 14 the fuel use use beyond me and the noise level was not what I wanted. If someone wants a faster trawler this boat in not the one. Keel is long and deep and the hull is heavy. Probably the same with GB boats.

 

[Pat T]

Any comments on the use or need of trim tabs on a GB 42C?

Trying to decide if I should remove mine as they have not worked since I bought the boat. I’m a single Cat 3208 375 hp and even at WO I can achieve not more the 12 knots.

I have twin 3208TA's at 435HP each. Seems the trim tabs only come into effect at about 2100 rpm if I recall. At that speed I might gain 1/4 knot. At 2400 I might get 3/4 knot. I usually (90% of the time) cruise at 1400 and average 9 kts. No TT necessary. Above 2400 rpm's, who knows, I might gain 1 knot. It's rare that I run above 2400 rpm so I can't comment.

 

[mike r smith]

Any comments on the use or need of trim tabs on a GB 42C?

Trying to decide if I should remove mine as they have not worked since I bought the boat. I’m a single Cat 3208 375 hp and even at WO I can achieve not more the 12 knots.

My old Fairways Trawler 38. 16.6 tons with a long deep keel. Twin 212 BHP Ford Sabres. The hydraulics were removed, and the tabs were fixed down. Would make 18kn and cruise at 12 to 14. I considered there was little penalty at 7 kn or 9 kn long range cruising.