Mercury ProXs 250 Leakdown

[kylemoodie]

<2B117088>

Good morning-
I am currently in the process of buying a 2015 Basscat Cougar with a 2015 Mercury ProXS 250 with 316 hours. I had the boat taken in to the local Mercury dealer to get the compression/hours checked on it before buying. They did a leakdown test and found that the number one cylinder leaked down at 10% and the number 5 cylinder leaked down at 12%, I do no know the readings of the other cylinders right now. Dealer said they like to keep everything at 10% or lower. The current owner of the boat told them to go ahead and fix anything they needed to since it is under platinum warranty for 3 more years. The engine tech then said that 12% was nothing to worry about and that it should be fine.

I have done some quick searches here regarding leak down tests, but I am not that familiar with them. Does anyone have any thoughts or advice for me on this? I am working on getting more information from the owner and dealer too.

Thank you

**added info***
the rest of the cylinders read as following: cylinder 2: 3%, cylinder 3: 7%, cylinder 4: 5% and cylinder 6: 8%
they also told me that they did the leak down without it being warmed up. Long story short, they assured me that everything is fine and that I will not have a problem, does that sound correct?

[Rick Collis]

Get the Platinum product protection transferred to you and don't worry about it. If it goes down product protection will take care of it. Good luck.

[EuropeanAM]

Leakdown tests must be done with the engine WARM. Same for Compression Tests. If the dealer performed either "cold" I would personally be thinking about looking for someone familar with properly performing these tests.

Anything over 10% is in need of repair NOW. Normally start looking for causes of leakage at 6% or higher.

What's the serial number?

[kylemoodie]

2B117088

this is my first time having a merc, but the dealer doing all this is very reputable.

[EuropeanAM]

If you have not already purchased this- I would strongly encourage you to have the Compression and Leakdown checked again (with the engine hot).

Even though it has Platinum Product Protection- you need to see valid (and much lower) leakdown percentages. Remember: Warranty and Product Protection cover DEFECTS in Materials or Workmanship. They do not necessarily cover every case of "it broke".

[angle iron]

Even if you have Platinum Protection and it breaks you're still going to be without a boat for a least a few days!

[BoBo]

Very good info. I had leakdown test done last year and was told all were at or <10%, and "that wasnt bad for a 2002 motor". Now I am not so sure, but I really doubt that motor was tested at full operation temperature. So will get er done again.

Sounds like leakdown and compression results should track one another. Any reason to get both done?

[EuropeanAM]

Sounds like leakdown and compression results should track one another. Any reason to get both done?

Very simply:

-Compression test is GOOD information.

-Leakdown Test is BETTER information.

-BOTH provides the BEST information (shy of tearing the engine down for inspection).