tube1

I have a 32 black thunder twin 502s at 3k rpms the boat starts porpoising at around t 3800 rpms the boat becomes unstable
and chine walking and it gets real loose like almost out of control. I have pulled the boat out of the water and checked the drives they are all the way down and equal. Manually checked the rams and made sure. Props are the same pitch so I am at a loss as to what would be causing this. Any Ideas as why this boat would porpoise at such a low rpm and what I can do to stop it.

1987pachanga22

Is this the black and white boat from the Ozarks area? The only other things to check is to see if one of the props hubs is slipping and or see if the drive ratios match. The boat itself should be a great running hull. If this is the black and white boat I would also look at the steering, I can’t remember what was wrong on it but the dealer pointed something out when we were looking at it.

mrv8outboard

Also check the prop rotation. Turning them in should get a little more speed but can make it a handfull to operate. Turning out is slower but it handles better. In most cases.

soldier4402

not doing anything crazy different with load, filling up fuel more, have boat loaded with more people or junk.

My boat tends to porpoise more when its loaded.

Griff

What props are on it?????? Do you have trim tabs?????

tube1

This is the boat from around the LOZ I know that the prop hubs aren't slipping because it doesn't rev up when pushing it over on plane and thats when there under there most stress. I believe I am rumming either 23p or 25p mirage ss props and they are both the same pitch. They have to be on the right way other wise the boat would go opposite of the direction that you want to go. Did that once so I am sure they are on the correct drive. I also have the big Kiekefer tabs. I can make the boat stop porpoising if I put some tabs down but when you start to go faster with tabs down the boat starts to get unstable. Alot of side to side motion. With no tabs I havent even put the coals to it yet because it really starts rocking from side to side almost like its about to break loose and come around on me.

hotjava66

Too much trim???

tube1

hot java

The drives are all of the way down and when out of the water I made sure that they were down as far as they could be by the distance left on the trim rams

1987pachanga22

Here are some pictures of the boat and drives. I was looking at that boat but couldn’t justify the price especially without the trailer. Hope you beat the guy up on price. Anyway if you want to know anything more about the boat, talk to
Coolerman
PF Marine

He was the original owner of the boat.


Good luck to you! Please post some pics and progress on the new forum restorations and upgrades.

http://s1136.photobucket.com/albums/...ack%20Thunder/

tube1

1987 pachanga
That is the same boat I beat the owner up pretty bad on the price because one of the motors and drives was sick and I already had a trailer so that really wasn't a factor for me. So you know the owner before the last owner? PF marine I cant find them in the phone book is that there full name? or do you have a numer for them. Any help would be appreciated.