I'm not saying it can't be fuel related, just what I've experienced in the past. If your recoil spring is still working properly, it's fairly easy. I'm not sure how else to check spark without knowing what value to ring out the wires etc. Then noticed some bubbling at a bolt near the carb. Its no secret that the most reliable way to ensure getting the correct parts for that Mercury Outboard or Mercruiser Sterndrive Engine is by going directly to the specific Mercruiser Product Diagram associated with your Mercury Marine Serial Number. I'm not familiar at all with the diaphragm pumps. Allow rope to be wound back into the housing and pull several times to check operation.
I don't know a lot about these motors, but I'm wondering if the diaphragm in the pump can get hard or dry rot when its old so that it won't move fuel as effectively. For engines built prior to 2006, contact any Mercury Marine dealer. Mercury On older Mercury outboards, going back into the 50's and possibly even earlier, the serial number would generally be viewed at the leading edge of the swivel bracket, as seen in the image below. While holding the sheave assembly in this position, the spring is under tension ,thread the replacement rope into the anchor pocket and out through the housing outlet, pull snug. I haven't even started on it yet, but I figured I'll need to clean the carb etc. It looks like the carb and fuel pump are more or less part of the same unit. It still runs, and it doesn't really backfire or anything, it just sounds bogged down.
Once they switched over to the tags, this was another number that often washed out and could no longer be read. Search The Mercury Outboard Parts Catalog by Serial Number. Over the years, manufacturers have changed where this information is located on an outboard. Note where the old rope is anchored, remove any remaining rope. A Mercury Marine engine serial number is a unique identifier all engines are manufactured with. The plug is pretty much brand new.
I'm not sure but it looks like the carb and fuel pump are part of the same unit on these motors. Maybe some luck will come my way. Ran great in a barrel for a little while, then started acting up again. Remove the starter sheave assembly, lay it upside down on the bench. This motor used to be my Dad's, and my brother got it when he bought the boat from my dad. I'll keep that in mind once I get the parts I need to get her running. After sitting for a bit would run great again for a bit then would do the same thing again.
It runs smoothly and idles well. Can you direct me to an alternate location for the serial on this powerhead? I would appreciate any constructive observations. Could that cause the motor to not carry a load? I got a serial number i think is Australian. Finding the model year of your Mercury outboard may be as simple as looking at its title if your state requires your Merc to carry its own, separate title. If not, locate the product identification plate on the engine mounting bracket. My guess based on what you have told us you brother had been using it and he told you it stopped working, then it sat for a couple of years, then you got it going, it ran across the lake good one time then started acting like it was down on power or bogging down but seems to idle fine would be that you are dropping a cylinder when it heats up.
Acted like it was running in 1 cyl. Note, if any disassembly is required, be advised that there are quite a few loose parts that make up this particular re-wind assembly. It can usually be found on a either a metal plate on earlier models or a sticker on later models. Now my brother wants me to take a look at his Merc 9. That freeze plug will have a serial number on it. The last time I ran the motor 2 years ago I put a new plug in it when I was attempting to fix it while on vacation.
My guess is that I will want to do both just to be sure. If the model year doesn't appear on yours, the serial number, also located on this plate, is the key. He let me borrow it a while back and now he could use it on his boat if I can get it running well for him. There are 2 locations where you may find this number. Later models used the same plate, but you'd find it on the side of the transom bracket.
If the number washed out, you may find a small sticker either on the cylinder head cover or the starter bracket. The great help I received from you all helped me to get my 79 Evinrude 25hp running like a champ. I took a look at the carb on the motor and also the parts breakdown on the parts site. Gary Parson's host of the Next Bite television show explains how to find an engine serial number on a Mercury outboard engine. I'll try to be as complete as possible below, while keeping this reasonably simple. When I took it out for the first time 2 years ago it pushed the little boat across the lake pretty fast.
This number contains vital information about the car, such as its manufacturer, year of production, the plant it was produced in, type of engine, model and more. I actually wrote down the website this time so I won't have to ask it again. Many newer Mercury outboards have the model year stated prominently on this sticker. I have a carb gasket kit and a fuel pump diaphragm and gasket kit that I plan to do this week. You mentioned putting in a new plug a couple of years ago, was that just One new plug, if so, why just one? I'd laugh at that but I have an Evinrude 25hp that is doing something very similar to this.
As far as what Mike said, I dont have much experiance with outboards, but my merc 20 is a p. Someone already suggested checking the plug wires. My first issue is that I can't find what the year of the motor is. Another is when you are ordering parts; knowing your serial number and supplying it to the parts vendor means that you will receive the proper parts for your motor model. Mercury vehicle history report may contain the following information: title problems, prior damages, unsafe salvage rebuilds, odometer mileage, theft, past sales.