I just replaced the tab cylinders on my 31 Commander and I've got to say that it's like owning a new boat. The boat planes with ease and can even stay on plane as low as 2600 RPM. Seems like the most efficient RPM is 3000 and which cruises us at 21MPH. If you don't have trim tabs, you may want to add them, it's a night and day difference. The boat runs nice and flat now too.
No, The system that was on there was made by Insta trim. https://insta-trim.com The hydraulic lines were cracked but the switches at the helm and the pump seemed to work correctly. When I was removing the hose from the starboard cylinder, I ended up breaking the nipple off of the cylinder which is actually part of the cylinder. I was pretty sure that I was looking at replacing the entire system with a Bennett at that point. I wasn't sure if I could even find the parts for it because I've never even heard of them. I did a google search and had two new cylinders with new hoses within a few days. Installed both of them yesterday, filled the system with hydraulic fluid and it's perfect. I can't imagine not having them on the boat now, it's like a totally different boat. Hard to believe such a simple system can change the entire attitude of a boat.
John Moore said:
Do you have the Bennett trim system ? Thanks. John
4th season with her and the tabs were not working either. Had an older aftermarket system that was no longer in business. We were able to get a new pump and control system and what a big difference also. I have been planning to cruise more and wanted to fix it. We just took ours up the Detroit River and across Lake St. Clair. Easy 20 mph at 2800 rpm. Just need to be careful in a following sea. Easy to bury the bow.
I feel sorry for the person who operates a 31 Commander that does not have tabs. My first experience with a 31 Commander was back in the mid 70's. A friend had purchased a 31 Commander in Holland, Michigan. We boated on the Illinois side of Lake Michigan so there was a lake crossing involved with a pretty new (1968) but untested Commander. My friends plan was to boat a few weekends in Holland and get to know the boat somewhat before going for a 100 mile lake crossing. Well, as the saying goes, S_ _ _ happens and my friend got in a car accident and got two broken arms as a result. We all know what good friends do, so I was elected to bring the boat across. I was teaching a Power Squadron navigation class on Saturday mornings and was not through until 11:00 am. A mutual friend picked me and the owner and his father and drove us to Holland. We got there about 2:30 in the afternoon. After filling the tanks and 5 five gallon gas cans for a CYA deck load, we got under way. Only nav gear on the boat was a decent compass. Outside of the harbor, I quickly " swung the compass" (if you don't know what this, don't ask) :-) and headed for Waukegan. My personal boat at the time was a sweet 30 Connie with tabs. This was a great performing boat, and I soon wished I was on my Connie. The 31 Commander desperately needed tabs. It required a whole batch of rpm to get on plane and keep the boat's bow down in a decent planing attitude. I even moved the deck gas supply to up under the seats to help. Fortunately, Lake Michigan was in a benign mood with nothing more than 1 foot seas so I was able to keep the rpm & speed up all the way across the lake. Once we finished the crossing, the following Saturday we trailered this boat to it's home harbor in Northern Illinois's Chain of Lakes. Once the owners arms were healed, he had the boat pulled and installed trim tabs as the very first thing he did to this boat. Moral of the story ---- 31 Commanders need tabs, --- BADLY !
Nice to here from Dick Morland. I grew up on a 1963 Connie that did not have nor seem to ever need tabs. The 31 Commander is a different story. If I get a couple of couples in the cockpit she wouldn't plane until about 3000, but still with bow pretty high. Now we can cocktail cruise at about 2500 very comfortably.