Swapping engines over??

[stevie wonder]

Hi all, haven't posted for a year or two.....

I have a mid 80's Mariner 150 (2.0 litre) which I am very pleased with, it is quite economical and gives a respectable turn of speed on my P18.
The outboard itself is mint and has the offshore saddle and low water pick ups so I don't really want to get rid of it... so my question os this:

Could I fit either a 2 litre XR2 (200hp) or a 2.5 carb (200hp) engine to my existing set up?

If so what would I need to do/change?

Thanks in advance everyone

Steve

[Burty]

either will go straight on with no mods, the xr2 will need pre mixed fuel though as they dont have oil pumps

[gazza]

Rob
If Steve were changing to a 2.5 carb powerhead would the exhaust have to be changed?

gaZ

[Burty]

erm, he might need to enlarge the 2 exhaust outlets in the tuner adaptor but i doubt it it would make much difference.

[stevie wonder]

Originally Posted by Burty

either will go straight on with no mods, the xr2 will need pre mixed fuel though as they dont have oil pumps

I have stripped the oil injection system off as I have heard too many stories of engines going bang when giving it some stick!

Originally Posted by gazza

Rob
If Steve were changing to a 2.5 carb powerhead would the exhaust have to be changed?

Presumably this is the exhaust can inside the leg? I would also need a different gaskets etc.

I take it that a 260 fit without too many problems then?

Thanks guys!!

[gazza]

Yes i thought that the exhaust can may be a different size / length,
Seems a straight forward swap then.


gaZ

[Burty]

any V6 merc will go straight on, it depends on which tuner you have as to if you need mods or not but the tuner adaptor plate can be opened out to suit, all gaskets are the same however if you go for 260 then you will need a fuel return and an electric pump, again if you only have the 1/2" pick up pipe you will have to change to the 3/4" pipe as more cooling is needed

[larby]

I'll 2nd what burty just said... I've just done this exact conversion, from 80's xr2 to a 2.5 200 carb motor. Port sizes on the top of the tuner were the same (though this would differ for a 260), all gaskets were the same, only issue is the cowling... it takes a lot of moving stuff around to fit even the carb motor under the xr2 cowl, let alone an injection motor!
Difference is out of this world though, go for it!

[stevie wonder]

Cheers for the advice guys

It looks like I may have a project on my hands, I'd love a 260, but i'll prob be a pussy and go for a 200hp 2.5 carb.......

I have to get it all to fit behind the clam shell cowling too.....

Steve

[Techteam]

You may struggle with the clamshell cowl. From memory the center section which hangs the clams sat on rubber bobbins attached to the exhaust plate. The later engines exhaust plate is different and not interchangable. Just a thought so check carefully before parting with any cash.

[still no worries]

just for your info i had a 260 efi on my 18 it would hold 86 mph on a gps.

you should get 80 with a good 200.

[Burty]

Techteam is correct. It will be very difficult to retain your clam shell cowl

[Daniel]

Hi all, dont say much on here but always lurking.

I've a 200 on the P18 and easily clearing 70 mph with a fair bit to go i would say, just have not had the balls / conditions / opportunity to do so, but summer is nearly here...

I built the 200 onto an old clamshell 150 leg and swapped it to a drop-on cowl at the same time, you get rear trim switches then too, easy enough to wire in - but why not buy an alien cowl at the same time? There was a cheapie on here recently, i was almost tempted...

[mike k]

Originally Posted by Daniel

Hi all, dont say much on here but always lurking.

I've a 200 on the P18 and easily clearing 70 mph with a fair bit to go i would say, just have not had the balls / conditions / opportunity to do so, but summer is nearly here...

I built the 200 onto an old clamshell 150 leg and swapped it to a drop-on cowl at the same time, you get rear trim switches then too, easy enough to wire in - but why not buy an alien cowl at the same time? There was a cheapie on here recently, i was almost tempted...

Speak to Gav.

[Cookee]

Originally Posted by still no worries

you should get 80 with a good 200.

Are you sure Derek?

[still no worries]

hi cookie
not sure it was 260 may have been less(old motor) but 100% it was 86 mph had terrified debbie sat next to me both ways holding gps not very happy, as for 80 mph out of a good 200 will let you know as mine is now on the water.......

[Cookee]

Originally Posted by still no worries

hi cookie
not sure it was 260 may have been less(old motor) but 100% it was 86 mph had terrified debbie sat next to me both ways holding gps not very happy, as for 80 mph out of a good 200 will let you know as mine is now on the water.......

I remember it going very well with the 260 on, but we only ever got 76mph? out of the XR2, so I would have thought 80 would be pushing you luck a bit?

But there again what do I know!

[still no worries]

john the best we saw with xr2 (196 hp) regularly was 78 mph with 24 raker so i would conclude with a 2.5 200 it should do a bit more......

[RHINO]

derek, still not as fast as my p19 with a 260 at windermere = 92mph and i have rya certificate to prove it, and that was with jackie hunt from p1 fame in as passenger

[Burty]

Rhino, how come Cookee has the record at less than that then??? was it only a 1 way run or something?