Merc. 25 hp. Question

Hello, my neighbor has a 25 hp Merc. S/N: 0T086044. M/N: 2000 25ELH 4 ST. I haven't seen this motor yet and he is asking for help in getting it running right. I don't know if it's carbed(I assume it is?) or not, anyway he says it starts fine when cold, runs fine for a few minutes and then sputters and dies. Upon restart, runs extremely rough when giving it the gas and you have to keep adjusting the throttle to keep it idling. Any thoughts/ ideas are appreciated. Thank You. It did have the water pump replaced last year by a local mechanic because of an overheat alarm and since that time it hasnt run right?

Definitely a carb-style engine.

Look at the BASICS first... Compression, Spark, and Fuel Quality/Delivery.

Don't overlook the fuel SUPPLY (tank, lines, bulb, fuel pump and filter).

Thanks Don. Are there 2 carbs on this engine? Are they easy to service as far as removing the float bowls etc? Sorry for the simple questions but I haven't seen this motor yet and I just want to get some info before I attempt to help my neighbor with this one.

It's a single-carb engine. Not overly intricate, but a good understanding of the various passages and jets is certainly helpful.

Service Manual is an excellent investment for the owner. :wink: