New member needin a lil help with cobra

[cobracrazed]

Well fellers, just hoping to get a little help with a prob Im having with my 19ft cobra with 200efi merc. I bought this boat about a month ago and love it but heres what I got.

When I first got the boat I realized that on the test run I was only getting about 5700rpms out of the motor at 63mph gps. I figured this was gonna need a little attention since the boat only had me in it and 1/4 tank of fuel and no gear what so ever. I also realized that when motor was trimmed down WOT I was at 17lbs of h20 pressure and about the time I got to full trim the guage would drop instantly to 8-9lbs! YIKES. So immediately I decided to lower the motor down a bit on the jackplate. The measurement from bottom of boat to prop shaft was 3.25". I went down on the jackplate 1/4 inch at a time and had to lower the motor 3/4" to get the h20 pressure to stay up. Actually it still drops a bit from 17 to 13-14?

So, after all this being said here is the other issue that I have. I got the boat fully loaded and got a fishing partner in it and now the boat is getting 5500-5600 at best and boat is now only getting 59mph.

So with all this adjusting Im going to get a new prop. Im running a 25 pitch tempest plus prop at the moment and needing to go smaller so what do yas think? Wholeshot is so-so but power loading the boat is an absolute joke. It is a gutless joke when trying to load on my own. I hit the hot foot to run her up to the rubber roller and it just boggs and wont come up in rpms. This is the part Im most concerned about. All boats Ive ever owned will rip right up the trailer to the roller and ill walk to the front of the boat and hook it.

Max rpm on my motor saids 5,800 although I know others saying they run these motors 5,900 all day long every day and have not ever had issues.

So whatchas think I should do on prop???

[Backlash Ar]

Check this link and see what others that have the same boat/motor are saying: http://www.bassboatcentral.com/viper.htm

[AlanW]

I'm thinking you might have some other issues, as a 25" Tempest should be a good prop for that rig and in fact what many people run on them. If everything is working right, an empty & light Cobra 190 with a Merc 200 EFI and 25" Tempest should be running upper 60s to 70mph (GPS) with RPMs maxing out right about 5,800. It should have a good holeshot, great mid-range and have no troubles at all loading onto the trailer.

Pad to prop shaft height should work well in the 3.25" to 3.5" below the pad area.
I would replace the water pump impeller and try moving the jackplate back up, but it would seem you still have some problem with something.

[cobracrazed]

well fellas heres what I found. Im still gonna have trouble getting onto the trailer I think but here is what I found. today after seeing how many folks are running the 25pitch tempest I figured i had another problem. Well this boat has a hot foot so sitting on the couch I got to thinking.......... I wonder if the throttle is being stopped from being opened all the way from the stop that was on the hot foot. Well, id say that is what it was because when I went WOT with the hotfoot the throttle on the motor was 1/4" form the stopping point so I adjusted it to where it would give it Wide open throttle. Now for the crappy part. Ive already sold my prop and have a new 23pitch that will be here tomorrow ups. Sucks, this is gonna cost me a lot of money.

I am very surprised at this deal to be honest. The boat is a 2002 and was a 1 owner boat before. The stop on the hot foot had paint on the treads and looked like it had never been moved so Im figuring this boat has prolly never seen WOT.