Trolling Valve

[capnlmk]

I'm thinking of upgrading from my R25SC to the "new style" R29.
I understand that the "trolling valve" on the R29 will allow the boat to be operated at low, trolling speeds. (We fish a lot...) But what does it actually do? Or, better said, what does the trolling valve change to allow slow speed trolling.
Last questions: for those of you with a R29 with the trolling valve, how well does it work, how slow does it allow you to operate with adequate control and do you use it when maneuvering in a tight marina?

 

[Shano]

I just had my Low-Speed Valve configured because it was part of the package. I have been corrected several times whenever I call it a trolling valve I get reminded that it is actually a low-speed valve for docking or manouvering in tight spots where you may not want as much thrust. It works by allowing the tranmission to slip somewhat. A Volvo certified mechanic told me recently that he definitely recommends not fishing with the low speed valve. THis is not my advice I am just passing along what I have been told. THe mechanic also said that if one runs a Volvo diesel at low rpms (less than 1500 rpm) then every hour run the engine up to 80% load for 10 minutes. There is a load indicator on my boat and to get my 435hp Volvo to 80% load I have to get her up to about 3200 rpm. You will find that different mechanics have different opinions on this subject. My 2nd to last boat which had twin volvo diesels I trolled with one engine all the time with it (sometimes I had to drag a sea anchor to slow it down a bit) and the advice from my diesel mechanic at that time was it was not ideal but ok as long as I ran it under load on the way back from fishing (which I had to do anyway). Maybe get some advice from Fluid Motion or better yet Volvo on this. As for using the low-speed valve for docking I find the thrust without the low-speed valve to be ok so I have hardly used it - this boat is way better than my last boat that had a Volvo D4 with duo-props and a leg that lurched when put into gear. I will add that I found this advice very disappointing as we like to go slow some of the time -- tho I guess running the boat faster every hour is not that big a deal.
Good Luck

 

[capnlmk]

Thanks. That was helpful, though not particularly encouraging advice. Certainly not an ideal solution for running for hours at slow trolling speeds. We have also towed a drouge to slow down when trolling, but maneuverability is not ideal when other boats are also trolling near you. I appreciate your post.

 

[Shano]

Your welcome. Hopefully not too discouraging! Being fishing obsessed myself we decided to get a 25hp high thrust installed on our CW30. While expensive initially because of the additional hardware needed (power assist pump, tank, vent, blower, etc etc) now we can under most conditions troll with auto pilot and the boat is quite responsive because whenever the kicker turns the rudder is also turning. The kicker is mounted in the centre of the swimgrid so it turns well both ways. If the water is rough then the autopilot can't handle into the wind 3' plus water etc so then we have to steer manually. The autopilot will handle down wind situation in rough water fine. So now instead of putting hours on the diesel at low rpms we are using a kicker which will hopefuilly give us 2000+ hours. THen when the kicker wears out not a huge expense to replace. Let me know if you want to see any photos or have any questions on this set-up. Also, the kicker is nice to have as a back-up and will push our boat at 5 knots.
Cheers,
Shane

 

[capnlmk]

Yes, I've heard some fishermen refer to their kicker as a "get home motor."
As a sailor for 50 years, I could count on the wind getting me home (eventually, anyway...). But these new-fangled, power-only boats are a different kettle of fish. ;-)
We have considered getting a kicker for our Ranger 25SC -- and may yet do so -- but have been trolling at idle speed (700 RPM and 3+ knots with no head or tail wind), taking the engine out of gear from time to time to slow the boat down. Not ideal for the Volvo 150 diesel or the transmission, I'm sure, but this approach is working so far to catch the Kokanee and Rainbow we are fishing for.
Always with my eye out for an upgrade, I was/am considering the Ranger 29 with the low-speed option, but unless I hear otherwise from experienced Ranger 29 skippers and/or Ranger factory folks and/or Volvo techs, maybe that's not the best upgrade option.
There's also the new-style Ranger 27 outboard with a kicker motor installed, but I kinda feel like I "graduated" from outboards to Diesel engines quite a few years ago. Would seem to be a bit retrograde to go back to an outboard, but I'm open to being convinced.
I'm about ready to start bouncing all this off Andrew at the Ranger factory to get his take on it, but haven't done so as of this writing. He's a straight shooter, though, and I know he wouldn't steer me wrong.
Thanks again for sharing your experience with me. It's so good to hear from someone who has "been there, done that."

 

[Andrew Custis]

Thank you for bringing this up. I talked to my main contact at VP today and asked the question to get his expert opinion on this. He is one of the main guys that has been with Volvo Penta for a long time and the guy that sees all of the issues. He said that this trolling valve or "low speed" option is something he would not be scared to use at all for fishing. He says it is the same idea as any other trolling valve (just like we used to do on the Yanmar BY series) with the only differences being that Volvo controls it electronically. This is much safer because it will shut down automatically when the RPM's reach a certain point to prevent failure verses the cable operated ones that if you left engaged could be bad for the transmission. In fact, he thought why would it be any different to use it for fishing versus being in a long stretch of water that required slow speeds?

With that being said, I don't think you should have any worries about using this for fishing. Be careful about when it is engaged (even though it is protected). I will say that my only experience with using the low speed on a D4 is the motor will shake a little at the low idle because of it being a counter balanced engine. This causes no harm to the engine but I would say noticeable versus running this engine at a higher RPM.

Thanks again,

 

[capnlmk]

Excellent, Andrew. Just the sort of expert info I was looking for.
I'll be in touch with you soon to discuss options for upgrading to the R29.