I just sold my boat with a 2001 125 ELPTO Mercury Saltwater series motor. The following is a quote from the buyer on another forum site: "I just purchased a boat that came with a 2001 125 ELPTO Saltwater Series Mercury. Before I purchased it we just fired it up in the previous owners driveway and it sounded fine. However when we took it out today in the water today, actually as soon as we fired it up, there was a fairly loud knocking sound. We took the boat out and it ran fine...WOT it performed excellent. My friend stated that his buddies 115 Merc also made similar sounds but I've owned over 15 2-stroke outboards and I've never heard knocking like that.
When we removed the cowl, the knock seems to come from the powerhead so could this be piston slap or a bad crank? The engine doesn't smoke any more than usual and runs great through the entire power band. It also starts fairly easily so am I over-reacting or could this be something significant?
One last thing - the previous owner also stated that the engine shut down last year at WOT and would not start back up. They ran in shore with the kicker, removed the plugs, cleaned them, and then it fired back up and they went back along their merry way. The boat has since been winterized and also serviced last week by the same dealer that has always worked on this boat. They changed out the impeller and also did a compression check which measured 115-115-120-115 which is normal. They also had the outboard running for over 5 minutes (on muffs) and never noticed any issues. The sound cannot be heard with muffs since the outboard is loud but then again once the engine is in the water the knock is quite loud." He then told me he took it to a dealer to have the motor checked out.The dealer told him" it was a most likely a rod bearing that almost 100% of the time leaves a flat spot on the crank and therefor would need to replace it and tear the engine apart to see how extensive the damage is." After agreeing to give him a full refund my question is this...does this sound as though the situation could be as bad as it sounds or could it may be some minor piston slap that I have never noticed?
When we removed the cowl, the knock seems to come from the powerhead so could this be piston slap or a bad crank? The engine doesn't smoke any more than usual and runs great through the entire power band. It also starts fairly easily so am I over-reacting or could this be something significant?
One last thing - the previous owner also stated that the engine shut down last year at WOT and would not start back up. They ran in shore with the kicker, removed the plugs, cleaned them, and then it fired back up and they went back along their merry way. The boat has since been winterized and also serviced last week by the same dealer that has always worked on this boat. They changed out the impeller and also did a compression check which measured 115-115-120-115 which is normal. They also had the outboard running for over 5 minutes (on muffs) and never noticed any issues. The sound cannot be heard with muffs since the outboard is loud but then again once the engine is in the water the knock is quite loud." He then told me he took it to a dealer to have the motor checked out.The dealer told him" it was a most likely a rod bearing that almost 100% of the time leaves a flat spot on the crank and therefor would need to replace it and tear the engine apart to see how extensive the damage is." After agreeing to give him a full refund my question is this...does this sound as though the situation could be as bad as it sounds or could it may be some minor piston slap that I have never noticed?