Ox66 250 bogging on acceleration

[Fanboatman]

My motor is a VX250TLRB on a Ranger bass boat and I have been fighting this issue for almost a year. After letting it warm up then try to get on plane the motor will bog for a few seconds(4-8) and then rev up and get on plane. I have replaced all filters, lp pumps, fuel hoses, primer bulb, had injectors cleaned and calibrated, replaced the lower unit due to previous owner damage, changed props, replaced shift cutout switch, replaced the crankshaft pulley/balancer, and found the #6 piston to be broken due to a rod bearing that went out so I had Hydrotec reman the powerhead and break it in for me. The fuel pressure under load stays at 35 psi at the problem rpm. Along with bogging when trying to get on plane it also will not rev up to power load the boat on the trailer. In both cases it will not rev over 2000 rpms. When getting on plane it will eventually rev up and get on plane, but when loading on the trailer it will not rev up. Hydrotec was supposed to and says they did check all the fuel and ignition components and they all tested ok. I also had a master tech at a dealer in Houston check it out and he couldn't find anything until he found the bad piston. I am at a loss here and would really like some help to figure this thing out. I have invested over $7k in this motor with the reman powerhead and new lower unit and still have the same problem. Thanks in advance if you can help.

[99yam40]

no idea when all of this happened, but if you got it back after a rebuild and it never ran correctly I would go back to the rebuilder

[Fanboatman]

This has been an ongoing issue since last September. The new lower unit was installed in February. I took it to the closest master tech to me in May who is in Houston at LMC marine. He claims to have checked everything that I couldn't and couldn't find any issues. He then started from scratch and found the broken piston. I picked it up from there and brought it home. I had to save up the money for the powerhead, then I removed and sent the whole power head to Hydrotec. They removed and checked all the components including all electrical and fuel system parts. they then remanufactured the powerhead, installed all of the components, test ran and tuned, and then broke in the powerhead on their dyno. I received the powerhead almost 4 weeks ago. I installed the powerhead along with all new fuel lines from the tanks to the motor, including a new Yamaha primer bulb. I went to the lake 2 days later and still have the same bogging problem. I have searched and searched online and the only similar issue I have seen is a couple people who had the shift cutout switch go bad. I installed that switch Saturday. Ii have not been able to take it out yet, but running on a hose the new switch seems to operate in the same way. I cannot see the rail move from the seat when I put it in gear, but when I manually activated the switch it drops about 200 rpms and sounds rough until I release the switch. That is why I don't think the switch fixed anything. It runs a lot smoother after the new powerhead, but I still have the bogging issue that I started with about a year ago. I have called and spoke to one of the guys at Hydrotec and he doesn't know what is going on either. It is a 10 hour drive to get to them for me. I would be willing to take it somewhere and have them figure it out. the problem I have is finding someone that knows these motors and is within 2 hours or so of me.