96 Evinrude 48hp Spl ... no speed

[Dennis1958]

I just purchased a 1996 Evinrude 48hp spl and took it out for the first time yesterday. It started fine but when I tried to take off it wouldnt pick up any speed. It leveled out going about 10mph. It is my first big motor and in trying to find out what might be the problem I did a search on Yahoo spelling out my motor details and another site suggested squezing the gas ball that is on the gas line and I realized that I didnt ever squeeze the ball at all yesterday... I just started it using the choke. Could that be the problem? The motor has set for 2 years because the owners wife had cancer but prior to that you can tell he kept the boat and motor up very well. It has been in a garage for the 2 years it sat. Ive also read that putting seafoam (whatever that is) in the gas tank could help clean the carb out . Is this something I sould do before I take it into a shop? Any suggestions on how to troubleshoot this? I will add that when I bought my first boat the prop was spun and it wouldnt get up speed but this motor dosent sound like that did...it sounds more like its bogged down or something. It didnt have a high pitch whinning or anything..

 

[Dennis1958]

Re: 96 Evinrude 48hp Spl ... no speed

I should add that it started fine..and the idle was fine but when I put it in gear it would take off but no speed.. then it would idle fine again....

 

[rickdb1boat]

Re: 96 Evinrude 48hp Spl ... no speed

Seeings how it sat for a long period of time, you can certainly assume that the carbs are clogged with old gummy fuel(Varnish). The only way to clean them is to disassemble and clean them thoroughly using carb.cleaner and then blowing them out with compressed air. Use new carb kits when putting them back together. Also, it would be a good idea to replace the primer bulb and fuel lines, as they are no doubt in need of it. And of course, replacing the water pump is a must do. The reason the other site suggested squeezing the bulb is that it forces fuel to the carbs and can indicates a faulty fuel pump if it runs good while pumping the bulb. Also, if you push the key in(Primer) and it runs better, that is an indication that the carbs are clogged. If you plan on doing service to the engine yourself, a Service Manual would be a big asset. The 48HP is a great engine if well cared for...

 

[jtexas]

Re: 96 Evinrude 48hp Spl ... no speed

I'm surprised it started without priming the fuel line. Your motor has a vacuum-operated fuel pump that can't lift fuel from the tank, so it must be primed by squeezing the primer bulb. The tank has a vent which must be open when the engine's running, to allow air to enter as fuel is withdrawn. Otherwise a vacuum is created.

Your engine doesn't have a conventional choke (with choke plates), it has a "primer" or "enrichener" solenoid, activated by pushing the key in, that allows fuel to drain into the cylinders for a cold start.

Your cold start procedure:
Squeeze the bulb until firm.
Turn the key to On, push it in and hold it for 5 or 8 seconds.
Turn the key to Start while continuing to hold it in, until engine starts.
Raise the high idle lever to maintain whatever idle speed is required to keep it from dieing until it warms up. If it starts to die, punching the key in momentarily will usually revive it.

Here are some possible causes of your symptoms:
* lack of fuel pressure.
* tank not vented.
* old fuel. If you haven't already, drain the tank and replace with fresh 87 octane gasoline mixed 50:1 with TCW-3 certified oil.
* clogged or gummed up carburetor.

Fuel additives can't clear carb passage that is completely blocked because fuel won't get to it. Or passage blocked by foreign matter.

If your problem is clogged carbs, it's past the point where a fuel additive would fix it - they need to be disassembled, soaked in carb cleaner and reassembled with new kits. With a manual, you could do it yourself.

 

[Dennis1958]

Re: 96 Evinrude 48hp Spl ... no speed

I would really like to service some of the things myself but I have to confess when it comes to motors on cars are any other motor for that matter I lack knowledge. I have the desire to learn but sometimes desire doesnt get the job done. I'm a cabinet maker by trade and have seen firsthand what an honest desire can do to a poor defenseless piece of lumber. If I get a manual for my motor.. and the right carb kit is it something a novice should even attempt? What tools are required? For instance, how do I measure the rpm's or do I even need to worry about that?

 

[rickdb1boat]

Re: 96 Evinrude 48hp Spl ... no speed

One thing at a time Dennis. Don't get overwhelmed by it. It's not rocket science trying to get these motors going properly. Buy a Manual and the carb kits. It will walk you through the job and if you get stuck, there's plenty of help here to get you through easily. Then to measure RPM's, you will have to install a Tachometer. This will tell you if the motor is propped correctly for the boat you have it on. Not nessesary to have one, but a good idea. The water pump is a must do before you run it. This too is not a big deal, but a bit labor intensive, as you must remove the lower unit to gain access to the pump. 95% of this stuff is unbolting and re-bolting parts back on. Basic hand tools(Wrenches, Sockets, Screwdrivers, Etc. ,Torque Wrench) will be all that's nessesary for this maintenence service. If you can build cabinets, you can fix this motor....Don't be afraid to ask alot of questions here and get that Manual...Parts are available from your dealer and right here at iboat site. If you need help with part numbers, just ask...Also, I see you're just across the river. Lots of dealers in this area for parts...

 

[jtexas]

Re: 96 Evinrude 48hp Spl ... no speed

A carburetor is really a simple device. Here's a video tutorial on carb rebuilding:
http://www.meegsonline.com/tmd/TMDsVideoChronicle2.wmv

Here's one on waterpumps:
http://www.meegsonline.com/tmd/waterpump.wmv
I think if you have a strong telltale and no sign of overheating, go ahead and run it, just do the waterpump soon as you can. Conventional wisdom says every two years, but they can go a lot longer if not mistreated. If you can hold your hand on the cylinder head for 5 seconds or so before you have to pull away, it's okay.

Not everybody has a tach but it's a good diagnostic tool, no doubt you'll eventually need one. Check out http://www.tinytach.com

 

[jtexas]

Re: 96 Evinrude 48hp Spl ... no speed

Let's recap:
If your fuel is over three months old or so, drain it and get fresh fuel. The old fuel is ok to use in your car if it's not contaminated.

If you have a built-in tank, remove the anti-siphon valve.

Make sure you have Champion QL78C or QL78YC spark plugs in good condition gapped at .040

Then try it again with the fuel line primed. Before you go to the lake, pump the primer bulb - it should get firm and stay firm for hours. If not you'll need to troubleshoot your fuel lines and fittings.

If it still bogs down, try pumping the bulb while it's bogging. It should either pick up RPMs or no change. If RPMs improve, it means weak fuel pump. Easy to fix. If the bulb collapses, it means you have an obstruction in the line on the tank side of the bulb, or else the bulb is faulty. Easy to fix.

If you get no change, activate the primer solenoid by pushing the key in while its bogging. It should either bog worse and die, or pick up RPMs. If RPMs improve, it means clogged carbs.

On both these tests you're just looking for any change in engine RPMs.

Let us know.

 

[Dennis1958]

Re: 96 Evinrude 48hp Spl ... no speed

Thank you and I will try this . I was thinking of using the carb cleaner this week before I take it back out. Do you think I should wait and do the tests you just mentioned before I do anything to the motor?

 

[jtexas]

Re: 96 Evinrude 48hp Spl ... no speed

You really can't clean a carb without taking it off the motor. I always prefer to rule out the easy stuff (like fuel pump) before taking that chore on.

There's one thing you can check, it's a lot of trouble though. Take off the air silencer (black plastic box on the front of the engine) - it's okay to reuse those gaskets just don't tear 'em up. There's a hex-head slotted screw at the bottom center of the carb float bowls. Remove those (gas will drain out). If the ends of the screws are a darker color than the rest of the screw, that's a sign your carbs are gummed up. But it's not definitive. And they can be clean sometimes even if you have an obstruction. A lot of trouble for "iffy" information.

I forgot to mention above...make sure the fuel tank vent is open.

 

[Dennis1958]

Re: 96 Evinrude 48hp Spl ... no speed

I took the boat out after I sprayed cleaner in the carburetor and ran sea foam for half an hour . I couldn't get any speed until I remembered what someone posted on here about holding in the choke while it was running. When I held in the choke it started to sound like it was dying but then kicked in and started to speed up. As soon as I let go of the choke it slowed down again. I checked the squezze ball and it was not hard. I tried to keep it hard by pumping but it wouldnt stay hard. My dad started to adjust a few screws to help the idle..and well..that didn't go well...it kept dying then. Long story short...I pulled the boat out and went to Walmart and I got a new fuel line and put the muffs to try it out today but I still couldn't get the ball to stay tight. The idle is now pretty high and I'm suppose to take it out fishing in 3 weeks. Any suggestions? I have a parts manual coming that I bought on ebay but I still don't have the service manual.... so I'm thinking that I might have to take this in the shop to get rebuilt and tuned up....but I really don't want to do that.
Do the carburetors need to be rebuilt? Could the gas tank be the problem? When I took the front off of the carburetors it didn't appear to me that they were dirty but I couldnt see inside. Is there something that pumps the gas to the carbs because when I tried to squezze and tighten the ball it wouldnt get tight . I had to pull the line next to the motor and press it a little so the air squezzed out and then plugged it back to the motor.