Buying and Rebuilding a Mercury 2.5 ltr 200hp XRi EFI

[strelitz]

Very new to this posting business, actually my first!

Looking to buy a Merc 2.5ltr 200hp Xri EFI that looks like it has not done much work (told that it has 40 hrs on the clock). The serial number is 0D029976 (Australia) .

The problem is that the boat and engin have been on the street for over 10 years - unused, though they have been under a plastic sheet. Any advice on this type of engin would be greatly appreciated as I dont want to be buying something that would cost me a fortune to rebuild (ie new ECU etc.). Are there any tests or checks that that I should do that will help with the decision to buy or not.

I am a reasonable home mechanic as I have just rebuilt a 1979 Johnson 85hp. The Merc would replace this engin as it somewhat under powered for my current boat.

Thanks in advance.

 

[Faztbullet]

Re: Buying and Rebuilding a Mercury 2.5 ltr 200hp XRi EFI

If the engine is blown you will need to send injectors and ECU off to have tested to see if one or the other has problems. If it has set a long time the VST tank is varnished up ,VST float stuck or damaged,inlet needle and set bad,fuel pump possibly frozen,all fuel filters and injectors will need removed cleaned or replaced,and fuel pressure regulator will likely be bad. You can easily spend up to a $1000 on just the fuel system as the regulator is around $200,fuel pump is $500 and filters are another $250

 

[strelitz]

Re: Buying and Rebuilding a Mercury 2.5 ltr 200hp XRi EFI

Faztbullet great advice.

I am planning to do a compression test and at the same time hook up a spark gap tester (i have one for the johnstone, a 4 plug setup what air gap should i set? Will the 4 plug tester damage the electronics?) i will need to jump the battery from my car as the boat has no battery. I was told to squirt a small amount of 2 stroke oil into the cylinders prior to turning the engin over, i know this will play havoc with the compression test but it should reduce damage to the dryed out cylinders??

So I should then know if i have spark at the cylinders (which hopefully means that all the electronics and ignition should be OK?) and if the engin is blown (loosing compressioin in a big way, or wont turn over!). Anything else that I should be looking at?

By the way thanks for the price guide on the parts unfortunatly here in Australia you can double that!!!!!

 

[Faztbullet]

Re: Buying and Rebuilding a Mercury 2.5 ltr 200hp XRi EFI

a 4 plug setup what air gap should i set?

Minimum 3/8.....

Will the 4 plug tester damage the electronics?

No...

i will need to jump the battery from my car as the boat has no battery.

Better to bring a battery with you as electronics are voltage sensitive on this engine...

I was told to squirt a small amount of 2 stroke oil into the cylinders prior to turning the engin over, i know this will play havoc with the compression test but it should reduce damage to the dryed out cylinders??

Good idea but rotate it by hand several revolutions before using starter....

So I should then know if i have spark at the cylinders (which hopefully means that all the electronics and ignition should be OK?) and if the engin is blown (loosing compressioin in a big way, or wont turn over!). Anything else that I should be looking at?

The stator can be bad on the high speed side and you still have spark at cranking, compression should be 110psi or more. Check the gearcase to see if it has water or metal in it....