Ranger 620/225 Vmax

[Jerry Gray]

Just purchased a new rig and have only had it out a couple of times. Ordered it completely factory rigged with jack plate (Bob's Machine Shop), kicker w/ Panther bracket and Pin Point system. First time out was only getting 43 mph (speedo) and further investigation revealed binding in the throttle control - I was only getting half throttle at best. After fixing that, am now getting 50 mph (speedo, haven't gps'd it yet)at 5500 rpm with full tank of fuel and two people at 36 - 3800' elevation.

I am running with the 23" Pro Series prop that came with the boat, and the motor is mounted (from the factory) in what I think is refered to as the "third hole" (I could raise the motor one hole and it would be as high as it goes). I have been running with the plate all the way down, and as soon as I start to raise it, my speed drops immediatley. This makes me wonder if lowering the motor may result in better performance. Something doesn't seem quite right here.

I did not buy this boat for speed, and am perfectly satisfied with it in every way, but do want to dial it in to perform the best that it is capable of.

I understand that the 23" Pro Series is the recommended prop for the Vmax, but am now beginning to think that it may not be the best prop for this engine height w/ jack plate. I have been reviewing all of the posts on this sight, and from what I am reading, most of the 620 owners are running 225 Optimax's, and the Tempest Plus seems to be the prop of choice.

Mercury's description of the Tempest Plus mentions incredible bow lift, ideal for heavy boats, and lots of blade area for running at higher engine mounting heights. It sounds made to order.

I am in the market for a spare/second prop and would appreciate any experience, thoughts or suggestions anyone may have to offer.

[easymoney]

I have a 620 with a 225 Opti, I am running a 21 pitch Mirage and the boat performs real well. I have seen this rig hit 58 mph but average is 52 to 55 fully loaded.I would expect the Tempest would perform close to this. Just my opinion.

[800proX]

LAST EDITED ON Apr-13-01 AT 03:12PM (CST)[p]on my stalker radar gun have seen my 620 with 225 opti, half tank and average gear hit 60 mph. i was laughed at for stating this last season, but just callin it as i see it. 2 guys, fully loaded, gas, will see mid 50's all the time, on radar, gps, and speedo. i was amazed at how close my speedo was, thought for sure it would be way off. but compared to the gps and radar (which for sure never lies) it is consistently within 2 mph (usually higher).

BTW - i run the 21 tempest.

jeff

[Jerry]

Jeff,

Thanks for the input. When they were laughing at you last season, what rpm's were you getting with the 21" tempest at 60 mph? Just curious since I am already max'd out for rpm's at 5500 and 50 mph.

[800proX]

assuming my tach was correct, i was in the neighborhood of 5600 - 5800 rpms if memory serves me well. still waiting for ice to leave here, but it was always around there, and like i said, i never had tach calibrated, assuming it should have been done at factory.

jeff

[Plainhook]

Am running a 620 with Opti Digital 225 and have a Mirage Plus 21
pitch prop. Have tried Laser (Great Hole Shot) but slow top end
speed. The boat came with a Tempest Plus 21 pitch and it was a dog out of the hole. Top end was 51 GPS with 2 big guys and fully loaded with gear and gas.
Decided on the Mirage plus 21 pitch because of great mid range holding power and top end of 54 GPS Fully loaded. As for the hole shot it is not as quick as the Laser but it is much better than the Tempest Plus.

[ELDON]

This is a new rig? If it is...
Why not ask your dealer about it?
Seems like they would want to make it work for you??
Dealer should have run it and had it right for you. I'd take it back, and let them do their job.
Was wondering why you went Yamaha. Been thinking that way, myself, (thanks, in advance.)

[Rigging]

5500 rpm with a 23p is faster than 50 on that Yamaha....(unless ventilation is occuring, causing excessive slip.)

[Scott D]

LAST EDITED ON Apr-15-01 AT 07:03AM (CST)[p]Don't be afraid to turn that motor up to 5800 rpm's. The book says 5500 but every Yamaha expert I talk to says they like to get it up to 5800 and some even say 6000 is no problem. The rev limiter on them is set at 6100. The Yamaha motors are geared a little lower than the Mercs, so when you compare what other people are using on their boats you have to take the gearing into account. You can turn a little higher pitched prop than the merc motors can on that boat, but not necessarily go faster.

I would go back to dealer though for help on the performance. He should help you get the motor height dialed in closer. What did the water pressure do when you raised the motor? I think you may benefit from the 23" Tempest but the Pro Series should also be performing better than it is. If you go to the Yamaha website they show a test of a Ranger 620 with no jackplate and a 23" Pro Series. They were turning 5600 @ 56.4 mph.

[Scott D]

Rigging, I agree with you. Jerry's speed figure are per the speedo so I think his speedo is off. I calculated the speed based on 20% slip and the speed should be at 55 mph at 5500 rpm and 1.81 gear ratio. If the speedo accurate then the prop slip is around 27% and something is wrong. Jerry, you really should gps it before deciding on a new prop.

[Scott D]

Jerry, is the motor broken in yet? Are you double oiling or is Yamaha not recommending double oil any more during break in? My Vmax is a '99 and back when I got it they were recommending double oil for break in (first 10 hours) but they were having problems with the o2 sensors getting fouled-up. I had heard from a service guy that he recommended not double oiling at all, but I don't know for sure what the official word is on that. Also, if you don't already know about Yamaha's Ring Free: you should try to religously use it. I think it is 1 ounce for every 15 gallons. It will help keep the o2 sensor from getting fouled and keep carbon from building up.

[Yankee]

I agree with a previous post that suggests the dealer was re-miss. (Unless it is all still ice where the boat was bought?)
Something is not right, and it may be as simple as the speedo tube being pinched somewhere between pick-up hole and guage.
What do you have to lose by taking it to the dealer??

[Jerry]

I am still breaking in the motor. Had 6 hours on it when I posted last week, now I am at 9 after the weekend. Yamaha still recommends 50:1 mix in the fuel during the 10 hour break in period, which I have been doing. My dealer has the Ring Free additive on order and I will use it religously as soon as they get it.

[Jerry]

Unfortunately the Ranger dealer that we purchased the boat through is located in another state. We took delivery of the boat in November just before the lakes froze, so we really have not had a chance till now to run it. Our closest "boat dealer" (who will service the motor)is an OMC and Yamaha dealer. We chose the Yamaha since our last boat had a 225 Ficht and we spent most of last season either in the shop or breaking in new powerheads.

[Jerry]

I agree - GPS is the only way to measure speed. We were on the lake over the weekend and the batteries went dead in our hand held GPS before we could tell anything (did not have any extra batteries). Will try it again next time out. We did try a couple of other props to compare to the 23" Pro Series. We tried the 21" Trophy (over-thru hub) and a Revolution 4. The Trophy gave us 52 @ 5500 and the Rev 4 55 @ 5500 with 3/4 tank - both performed better than the Pro Series, but the Trophy seemed to slip excessively on hole shot. The Rev 4 had considerably more bow lift than any of the others - it seemed to lift the whole boat up out of the water and handled very well.

[Jerry]

The lake was not quite iced over when we bought it - we got a couple of hours on it in November. The speedo tube was pinching the first couple of times out, but our "local dealer" took care of that. The Ranger dealer that the boat was ordered through is located in another state, since we do not have a Ranger dealer here in town.