Alex75 Posted January 30, 2021 Share Posted January 30, 2021 Hi All I have a Mustang V1700 boat with a Johnson 1981 90hp motor plus and 9.9hp Suzuki motor on the back, which came with the boat. we took it out today and it sat very low in the rear my son and I were in the front and we had one person in the back, even before we got in there was 1 person and you could see from the outside it was sitting low, it was also covering just the 2nd exhaust holes and if I was moving you could see it covering the holes. also the motor would not hit full throttle at full throttle it would go very slow but move without issue but would go over a certain speed don’t know the RPMs as it’s not working on this boat. No sure if I should raise the motor and just use the existing holes just move it higher or if there’s something else I could do, I have a 60l steel tank under the floor but it’s right in the middle of the boat. I didn’t get the best photos but I’ll attach what I have and advice would be great. thank you all. Link to comment Share on other sites More sharing options...
Fab1 Posted January 30, 2021 Share Posted January 30, 2021 Water logged hull, overweight engines,gear,and people are the only things i can think of that will make it sit low. Process of elimination. If the boat is overloaded due to the above or the motor has lost compression,etc it will give you the performance issues you're having. Motor to low is not good too. Take a proper photo of the cavitation plate and bottom of the hull so we can see. Did you just buy the boat? Cheers. Link to comment Share on other sites More sharing options...
Alex75 Posted January 30, 2021 Author Share Posted January 30, 2021 14 minutes ago, Fab1 said: Water logged hull, overweight engines,gear,and people are the only things i can think of that will make it sit low. Process of elimination. If the boat is overloaded due to the above or the motor has lost compression,etc it will give you the performance issues you're having. Motor to low is not good too. Take a proper photo of the cavitation plate and bottom of the hull so we can see. Did you just buy the boat? Cheers. Hi I just took some photos I hope they help, yes I did just buy it. Link to comment Share on other sites More sharing options...
Fab1 Posted January 30, 2021 Share Posted January 30, 2021 (edited) Get that boat checked out by someone reputable mate as it looks like it's had transom/hull repairs done in the past. You can tell by the discoloration and brush strokes. If it sits low like you say I wouldn't be surprised if the under floor area and flotation if any is full of rot and water. That boat looks like it's had a hard life mate.Let's hope I'm wrong.Hopefully someone on here can recommend someone local to you to take it to. Edited January 30, 2021 by Fab1 Link to comment Share on other sites More sharing options...
rickmarlin62 Posted January 30, 2021 Share Posted January 30, 2021 For starters take the auxiliary off and get the person sitting down the back to stand up the front when u take off and travel see if that makes a difference some hulls need weight up front to balance things also what pitch prop sre you running 1 Link to comment Share on other sites More sharing options...
Alex75 Posted January 30, 2021 Author Share Posted January 30, 2021 13 minutes ago, rickmarlin62 said: For starters take the auxiliary off and get the person sitting down the back to stand up the front when u take off and travel see if that makes a difference some hulls need weight up front to balance things also what pitch prop sre you running Hi and thanks we did try that made him sit right at the front made a slight difference but not a lot. sorry I’m new to boating, how do I find out what pitch prop I’m running please. also when I put the throttle in full there water much speed but the front started lift high even with 3 of us at the front. thanks for the help Link to comment Share on other sites More sharing options...
Steve-o Posted January 30, 2021 Share Posted January 30, 2021 Sounds like you'll have no problems planing at speed. Link to comment Share on other sites More sharing options...
Fab1 Posted January 30, 2021 Share Posted January 30, 2021 Look at the propeller for the size pitch.There will be a number on the hub.Are you using your trim/tilt to trim the motor in when taking off and trim it out as you gain speed? Link to comment Share on other sites More sharing options...
Alex75 Posted January 30, 2021 Author Share Posted January 30, 2021 1 hour ago, Fab1 said: Look at the propeller for the size pitch.There will be a number on the hub.Are you using your trim/tilt to trim the motor in when taking off and trim it out as you gain speed? Thank you, I will have a look in the morning, yes I had the trim in when taking off, even tried once I was taking off to trim out but at full throttle It wasn’t going fast at all, could that be due to water close and going in the secondary exhaust holes? or I’m thinking carby high speed jet? appreciate the help Link to comment Share on other sites More sharing options...
Fab1 Posted January 30, 2021 Share Posted January 30, 2021 32 minutes ago, Alex75 said: Thank you, I will have a look in the morning, yes I had the trim in when taking off, even tried once I was taking off to trim out but at full throttle It wasn’t going fast at all, could that be due to water close and going in the secondary exhaust holes? or I’m thinking carby high speed jet? appreciate the help Take to get looked at properly mate as we will just be guessing what the issue really is. 1 Link to comment Share on other sites More sharing options...
rickmarlin62 Posted January 30, 2021 Share Posted January 30, 2021 Size n pitch are written on outer edge of hub or side of prop 13 1/4 ×17p you may be running a 19 or 21 and be overpitched also if you are travelling at slow speed when your looking at water level up motor you probably have two people down the back and the nose in the air if the water was up thst high while travelling on the plane you probably should have sunk as your hull would of been half submerged 2 1 Link to comment Share on other sites More sharing options...
zmk1962 Posted January 30, 2021 Share Posted January 30, 2021 Alex, Does the motor rev up in neutral with the ear muffs on when the boat is out of the water? Does the motor rev up in neutral when the boat is in the water? cheers Zoran 1 Link to comment Share on other sites More sharing options...
Alex75 Posted January 31, 2021 Author Share Posted January 31, 2021 1 hour ago, zmk1962 said: Alex, Does the motor rev up in neutral with the ear muffs on when the boat is out of the water? Does the motor rev up in neutral when the boat is in the water? cheers Zoran Hi Zoran, yes it does I tried that on the water and out of the water when we came back. Link to comment Share on other sites More sharing options...
Alex75 Posted January 31, 2021 Author Share Posted January 31, 2021 Think I found the issue I drilled a hole in the 2 sides so far on right side and water came pouring out it’s been 7 minutes and still going Link to comment Share on other sites More sharing options...
zmk1962 Posted January 31, 2021 Share Posted January 31, 2021 (edited) That's not good. As you drilled through the transom, did you get any timber coming out? Was the timber dry or wet/waterlogged? Edited January 31, 2021 by zmk1962 Link to comment Share on other sites More sharing options...
Alex75 Posted January 31, 2021 Author Share Posted January 31, 2021 2 minutes ago, zmk1962 said: That's not good. Nope Might have to get some bungs on each side, doesn’t look like the water is coming through to the middle bungs. had a guy come and check the boat he said transom is very solid and after we found this out he did install a inspection plate to look under the floor and he used a camera and said it was still very solid underneath. Link to comment Share on other sites More sharing options...
Fab1 Posted January 31, 2021 Share Posted January 31, 2021 9 minutes ago, Alex75 said: Think I found the issue I drilled a hole in the 2 sides so far on right side and water came pouring out it’s been 7 minutes and still going I knew it! Link to comment Share on other sites More sharing options...
zmk1962 Posted January 31, 2021 Share Posted January 31, 2021 So any idea where the water is entering this cavity? Strange that this cavity has no bung already. I'd expect it to drain to one of the lower two bungs you have. Link to comment Share on other sites More sharing options...
Alex75 Posted January 31, 2021 Author Share Posted January 31, 2021 1 hour ago, zmk1962 said: That's not good. As you drilled through the transom, did you get any timber coming out? Was the timber dry or wet/waterlogged? Timber was very dry and solid Link to comment Share on other sites More sharing options...
Alex75 Posted January 31, 2021 Author Share Posted January 31, 2021 1 hour ago, zmk1962 said: So any idea where the water is entering this cavity? Strange that this cavity has no bung already. I'd expect it to drain to one of the lower two bungs you have. That what I thought too, but once water stopped coming out of the bottom 2 bungs it was still coming out of the side holes I drilled. so I think I will put an extra bung on each side. I just did a water test filled up the boat and looks like under the carpet there is small crack and there’s screw holes that have just been carpeted over. so I will remove the whole carpet. And check the whole floor. Plus one of the bungs was leaking too. I will replace everything this was how much water came out these are 49L buckets Link to comment Share on other sites More sharing options...
jeffb5.8 Posted February 1, 2021 Share Posted February 1, 2021 On 1/31/2021 at 5:47 PM, Alex75 said: That what I thought too, but once water stopped coming out of the bottom 2 bungs it was still coming out of the side holes I drilled. so I think I will put an extra bung on each side. When you pull the floor, it should have a drain section to allow the water that gets in there to flow down to the next chamber where the bungs are already. Adding bungs might just hide the issue. Link to comment Share on other sites More sharing options...
Alex75 Posted February 1, 2021 Author Share Posted February 1, 2021 On 1/30/2021 at 7:44 PM, rickmarlin62 said: For starters take the auxiliary off and get the person sitting down the back to stand up the front when u take off and travel see if that makes a difference some hulls need weight up front to balance things also what pitch prop sre you running I found the number on the prop 389948 Which I search and came up as this 13-3/8" x 17P Link to comment Share on other sites More sharing options...
Alex75 Posted February 1, 2021 Author Share Posted February 1, 2021 (edited) 13 hours ago, jeffb5.8 said: When you pull the floor, it should have a drain section to allow the water that gets in there to flow down to the next chamber where the bungs are already. Adding bungs might just hide the issue. Thanks before I drilled the holes I had the boat raised very high to see if the water would come out of the lower bungs that are there, but no water would come out after the a small amount came out first, until I drilled those holes. that’s why I thought adding another 2 bungs on the side might help to at least drain the water in there. thanks for the message. Edited February 1, 2021 by Alex75 Update 2 Link to comment Share on other sites More sharing options...
rickmarlin62 Posted February 1, 2021 Share Posted February 1, 2021 17 pitch prop is the right size a 19 might not reach peak revs 1 Link to comment Share on other sites More sharing options...
Alex75 Posted February 3, 2021 Author Share Posted February 3, 2021 Hi all, might be a stupid question so sorry if it is remember I’m new to this, do these type of Fuel Tank Breathers always stay open or can they be closed off? (See the photo I have one of these at the back of the boat) just wondering as when I took the boat out the power was still not there at full throttle I was going really slow, I’ve put new plugs spark is good, I’m going to do the carby and fuel pump next anything you guys think I should check? compression is around 125 all cylinders. thank you all for you help and advice. Link to comment Share on other sites More sharing options...
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