'88 Yamaha 150 Pro V- Idles fine but dies when in gear

[bassfishingfan]

I recently purchased a 1988 Skeeter with an '88 Yamaha 150 Pro V engine. The engine runs just fine on earmuffs but when it's out on the lake it will idle all day long but as soon as you put it in gear it dies. It has all new spark plugs, the carbs have all been cleaned and rebuilt, it has new fuel pumps and there is no water in the engine. Any suggestions as to what it may be? Thanks in advance.

 

[Capt Ken]

Not running on all cylinders. Find which cylinder is not firing by pulling spark plug wires

 

[bassfishingfan]

All cylinders have been checked and are all firing correctly.

After trying everything that I can do and putting a lot of time into it already I think I'm just going to save up and take it to a mechanic.

Thank you for your response.

 

[racerone]

A wise man would start with a compression test.

 

[99yam40]

If all cylinders were sparking and burning fuel properly it would not be dieing

Apparently it cannot handle the load of the prop in water, so motor is not running on all cylinders

As said compression is the 1st thing to check any time a motor has a problem

 

[bassfishingfan]

Compression was tested and is fine according to mechanic. The boat runs fine on earmuffs. The mechanic was supposed to take the boat out on the lake today and I am waiting to hear back from him on what the issue is.