Hi Guys

What are your thoughts on:
Mercury 40hp lightning xr 2007 two stroke outboard?

With electric start and trim.

Looking at one on a seanymph V13









Have you herd anything bad about this outboard??
I have always stuck with yamaha

Please let me know what you think


Thanks

Aidan

We have the Mariner version of this motor which I think is almost exactly the same but with a different cowling, for some reason I'm not sure of.

First I heard of that OP? I have owned 3 of them, one did huge hours, and despite two that did allow a small bit of water into a cylinder via a incorrectly torqued exhaust plate gasket, they have been utterly reliable. I know many people with this engine who are having a great run - I'd be interested to know how is the water getting in on the ones you've looked at? I'm pretty good with maintainance so picked it up via a slightly wet sparkplug early - but can understand how most would never know.

How do you test for a pourous block as assuming it would not be obvious?

Like I said in the post, look inside the motor for signs of water entering the cylinders.

Apart from that, the only way would be to get torque plates and stuff made up and pressure test the block. That would require pulling motor off and apart.

The sympton is poor idling.

Aidanc, will get some photos up later today when I have a minute.

I had one on my Mclay 460 that i sold 6 months ago.
From new it bogged when the hammer got slammed down from idle and ran like a sack of hairy ring pieces when trimmed up while in shallow water.

Solved that problem by getting it tuned to 50hp (these 40hp motors are apparently just detuned 50hp outboards) havnt got the paper work any longer to see what was done.
Ran like a dream after its tweaking and ran slightly more economically

My 2c on the discussion

Hi Guys, sorry to write in this old thread but it is exactly what I was looking for.. I have this motor, a while ago I found some water in the lower cylinder, so I ordered both new exhaust cover gaskets and head gasket. Took the old gaskets off, but when I am starting to install the new exhaust cover gaskets, I notice that the inner exhaust cover (the inner plate) is not symmetric, it has a kind of U shaped protrusion that goes towards the exhaust exit in the cylinders. This "U" is shorter in one of the ends and I don't remember how was this originally placed (with the shorter part up or down). Do the people that have replaced these gaskets remember how should this be placed? Exploded views of the motor that I got are not helpful at all..

Longer one at the top, it deflects the exhaust gasses down.

HI guys,

Outboard Performance wrote: If you have done the side plate gaskets, and done the head gasket and still getting water in, chances are you lucked out and got one of the motors with the pourous block. Unfortunately, the only fix is to replace the powerhead, or motor. Powerhead will set you back about 5 grand. Why didnt Mercury do a recall? beyond me...

Hahaha........ You know Mercury, unless heaps of people complain, it wont happen

hmmmm  sounds like exactly what happened with this same engine and the carburettor issue, all the Tohatsu guys fixed the problem and yet Mercury where still in denial that the problem even existed !!!