Mercruiser 4.3 at Mile High

[jmatteus]

I may be picking up a 99 Bayliner 2050 with a Mercruser 4.3 190hp. The boat was dry docked in Tampa and I’m in Colorado. I have heard from different dealers that say I might need to change prop and/or gear ratio. <br /><br />I can see changing prop pitch, but is it really necessary to change the gears? If so how difficult a job is that? What will the boat do (or not do) to indicate I need a gear change?<br /><br />Does the 4.3 have enough HP to pull a skier or 2 at 5000’?<br /><br />Jeff

 

[blderman]

Re: Mercruiser 4.3 at Mile High

I don't know about the gears, but I could definitely see a prop change. Is your engine a EFI or carb? If it is a carb then you'll need to change your jetting too. <br /><br />J

 

[thompmik]

Re: Mercruiser 4.3 at Mile High

Milehigh,<br /><br />I live up in Gunnison and boat regularly on Blue Mesa. We are at 7700 feet up here. I have a 4.3 with a 4bbl carb on a 20ft Maxum. I pull two skiers at the same time although both are on two skis. Of course wake boards are no problem. I had the carb tuned to this altitude when I moved up here. I have a 15 p prop for pulling and playing and a 19p stainless for cruising. <br /><br />Anyway, that is my expierence with the 4.3 up "high".

 

[jmatteus]

Re: Mercruiser 4.3 at Mile High

thompmik,<br /><br />Thanks for the reply. Sounds like you moved up here from the "Flat Lands" so I'm guessing you have the standard Gear Ratio Package as opposed to the high-altitude one.<br /><br />What are you getting for top-end speeds with your different props?

 

[thompmik]

Re: Mercruiser 4.3 at Mile High

Yes, I do just have the standard gears. I don't know about top speed. Speedometer is broken. I'm going out with a gps this weekend. <br /><br />I get 43 MPH WOT (GPS) at Lake Powell, with 3 190lb guys on board and full gas. 19p stainless<br /><br />I'll let you know what I get this weekend.

 

[jmatteus]

Re: Mercruiser 4.3 at Mile High

thompmik <br /><br />I just wanted to see if you had a chance to test your MPH on your 4.3. Were you able to clear 40mph in Gunnison?

 

[thompmik]

Re: Mercruiser 4.3 at Mile High

I had to get a new upper unit. It is on but I have to break it in. Instructions say not to go WOT during the first 10 hours. I should get hours 9 and 10 on her tomorrow night. So this comming weekend I will be able to go WOT. I'll let you know what I get.

 

[thompmik]

Re: Mercruiser 4.3 at Mile High

Milehigh,<br /><br />I took it out last night. Did not go WOT. I did go to 4000rpm's. I got 38.5 mph (gps) with 550Lbs. of people and 15 gallons of gas. <br />This was with the 19p stainless prop. <br />The break in hours are over now and I should get to hammer it a little this weekend. I'll let you know.<br /><br />Thompmik

 

[jmatteus]

Re: Mercruiser 4.3 at Mile High

Thompmik<br /><br />Thanks so much for replying. 38.5mph is pretty darn good for just cruising speed. <br /><br />So did you change gear ratio's on the upper unit?<br /><br />Thanks again for your help. <br /><br />Jeff

 

[ffchstr]

Re: Mercruiser 4.3 at Mile High

Milehigh,<br /><br />I used to live in Colorado (hope to get back there soon!!), and spent quite a bit of time out at Empire Reservoir. Plus the occasional trips to Carter, Boyd and John Martin. The elevation change between all those different lakes runs about 1600'(ish). I ran my 20' Sea Ray with 4.3LX on 19p prop and managed a respectable 48mph, on average. That was with 2-3 people on board and over half a tank of fuel.<br /><br />Hope this helps...<br /><br />Dave

 

[thompmik]

Re: Mercruiser 4.3 at Mile High

MileHigh,<br /><br />I ran across this article and thought it might help you out. By looking at this it seems you should not change your gear ratio. Hope it is helpfull. <br /> http://www.bravodrives.com/bulletin/servicecruiser/bullet/93/sb937r.pdf <br /><br />To answer your question. I did not change mine. I have the 1.84:1

 

[jmatteus]

Re: Mercruiser 4.3 at Mile High

thompmik, <br /><br />Thanks so much for the link to the service bulletin. That answers my question perfectly. I can’t believe how many Boat Dealers try to put doubt in my mind about buying a used boat from Tampa. <br /><br />Anyway I pick up the boat last weekend (long long drive) and it is in awesome conditions. I pulled some hoses to check for rust/corrosion and I could not see any. I’m bringing it in for a tune up and carb adjustment next weekend and hope to be on the water in soon after that. <br /><br />Thanks again.<br /><br />Jeff