Hi ! I got a Fountain 38 with 2x 525 efi and one it that is said to be rebuilt with piston rings etc. Old original Engine is fine but the other smells gas, feels like 100hp is missing and uses oil and much more gas then the other . Boat only goes 70 mph and should do like 80 at least ?

Anyone that hade the same problem ? I have tried 28p and 30p bravo one props and -2 lower unit.. Almost same speed.

Engine needs to be scanned to get an idea of problems. If you own Merc Race engines and do not have a Rinda scan tool your throwing darts in the dark.

Hi , we have done it no codes exept low water pressure and once we found low fuel pressure , then we ran it with the gauge on the fuel rail and it was okey..

Compression is ok on all 7 cyl, Can one or two bad injectors couse the fault ?

Does the scan say that it is at 100% power?

If you have the Rinda or laptop equivalent then you can check for 100% power and do individual cylinder tests. When was IAC unit changed? They are not as much of a problem as 600 and 700 IAC but still can cause problems that do not show up on a scan.

I dont understand this statement ??

No doubt you need to scan and see what codes you've got but you also need to perform a cylinder leak down test because if you have oil consumption and low power you may have internal damage which at that point you would want to stop using to avoid further damage. Best of luck keep us updated. Sincerely Laz Mesa

did both engines reach MAX wot rpms ?

Look at MAP readings while scanning, then compare between the 2 engines at same rpms thru out

Fuel pressure readings are ?

Spark plugs look like ? oil fouled, gas fouled or lean or ???

compression test on ALL 8 was ????????