Evinrude 35hp runs full throttle when started.

[macherry]

Hi all.

I purchased a 17' jonboat with a 35 hp evinrude @1977 vintage. It was in the water and functioning 2 days before purchase. I have just now gotten time to 'play' with it and get familiar with starting and such, before taking it out. I have little experience with this type of motor.

The issue is that when I attempt to start it, after setting the electric choke on and throttle at minimum, it fires up and immediately runs full throttle, or darn near. I cut it off after a second or two to protect it, since I do not know the issues. I do have a flushing attachment on it for water flow. The fuel would be about 1.5 months old, same fuel the past owner used and the tank is 1/2 full or better.

I am not sure where to look first, past making sure the throttle linkage is really at minimum throttle, which it is.

Any suggestions would be greatly appreciated as I have checked the repair manual for the motor and no good information on an issue such as this.

Thanks in advance for your guidance!

Mark

 

[JDusza]

Re: Evinrude 35hp runs full throttle when started.

How's it start without using the electric choke? Full throttle?
If it is starting at "full throttle", then regardless of where the linkage is, the carburetor throttle plate is being opened.
Move and observe the throttle lever and related linkages without running the engine.
Does the carburetor throttle linkage under the hood respond to the throttle lever at the helm?

 

[macherry]

Re: Evinrude 35hp runs full throttle when started.

Thanks for your response JD. I did carefully follow all of the linkage and found the follower that hits the CAM (engine center/front) was sticking well above idle when the 'helm' controls were taken to idle. Did a bit of repair and cleaning and have good throttle now at starting, although it idles quite rough...at least it idles!

Now to figure out where the water flow is to come from! I have looked at videos, shop manual and such. It is a 77 35hp unit. It has the small outlet coming out from the bottom of the engine casing (from block through hose to the outside), which does not show any water flow. There is also a small hole on the starboard side of the lower housing that does have water flow, just from the pressure of the water supply hose. I do not see any from the exhaust.

I did not run long (maybe 15 seconds) because I saw that there may be no decent water flow. I am using the 'ear muff' style flushing attachment.

Anyone know exactly where the water flow should be showing? I know it is a newbie question, but an important one.

Thanks again for all of your expertise and willingness to share it.

Mark

How's it start without using the electric choke? Full throttle?
If it is starting at "full throttle", then regardless of where the linkage is, the carburetor throttle plate is being opened.
Move and observe the throttle lever and related linkages without running the engine.
Does the carburetor throttle linkage under the hood respond to the throttle lever at the helm?

 

[jasper60103]

Re: Evinrude 35hp runs full throttle when started.

Yea, you should see water pee from the bottom of the engine, and spit from the exhaust relief ports on the back of the leg.
Here's a good example...
http://www.youtube.com/watch?v=Pohk-6zuCwI&list=FL3QpDWv9v2BbCl-1-MP9JSg&index=1&feature=plpp_video

 

[JDusza]

Re: Evinrude 35hp runs full throttle when started.

Glad it worked! This is a great forum. You'll get good advice here. And, not to start off on a wrong foot, but, did you see the rig run "2 days prior" to purchase? Did it have these issues? We'll get you where you want to be. Hang in there.

To be certain we're on the right track, let's have the model number from the engine. I am looking at parts pictures. I believe the cooling water pee-pee hole is midway up the right rear lower cover; out the lower cover nipple. The water exits the power head at the upper right rear running the to pee-pee hole via rubber tube. The thermostat is on the top of the cylinder head.

Here's the basic flow, input to output.
As the engine sits on the housing, water enters the lower potion of the exhaust housing, priming the water pump. The water pump impeller pumps the water up the water tube into the bottom of the engine block. Water fills the block, holds at the thermostat until it opens, then water circulates through the block and out the pee-pee hole and exhaust.

If no water comes out the pee-pee hole in the cover, I would go back to where its hose exits the engine block and remove the hose from the block.
Restart.
Does water exit the block?
Yes, the hose is blocked.
No, the water pump / water tube is malfunctioning or the engine is blocked (thermostat stuck closed or engine water path otherwise blocked).
Don't be scared.
If you're in the lower unit replacing the water pump impeller, replace the lower water tube grommet and o-rings while you're there.
Check the condition of the lower unit oil, too, for if it has water, then the lower seals are likely blown and should be replaced while you have the lower unit off.
If your problem is in the engine block and you have to remove it from the exhaust housing, replace the upper water tube grommet while you're there and don't try to re-use any gaskets.
Keep us posted,
J

 

[macherry]

Re: Evinrude 35hp water flow

Re: Evinrude 35hp water flow

Hi Jasper,

Thanks for the video link. Picture worth a thousand words (and many manual pages) still holds true! I now see where I am lacking water flow. I appreciate it and will now take JD's advice and have a place to begin troubleshooting. Thanks again, Mark.

Yea, you should see water pee from the bottom of the engine, and spit from the exhaust relief ports on the back of the leg.
Here's a good example...
http://www.youtube.com/watch?v=Pohk-6zuCwI&list=FL3QpDWv9v2BbCl-1-MP9JSg&index=1&feature=plpp_video

 

[macherry]

Re: Evinrude 35hp water flow issues

Re: Evinrude 35hp water flow issues

Thanks for the advice JD. The Model number is 35EL77C.

While I did not see the engine run, I know these guys take this out each Wed. morning, so I am assuming it was true, but who knows, maybe it stopped working on the last trip! No issues were reported and I did see reports/reciepts of a recent 'check out' from a local boat service shop that indicated on problems, about a month before purchase.

I will do some troubleshooting today, if time allows. The video I saw helped to support your advice and gave me a good look at what I should see!

I will most certainly keep in touch as I am sure this is not the last question about this. Thanks to everyone for advice and yes, this is a great forum and newbies are not treated like the plague!

Mark

Glad it worked! This is a great forum. You'll get good advice here. And, not to start off on a wrong foot, but, did you see the rig run "2 days prior" to purchase? Did it have these issues? We'll get you where you want to be. Hang in there.
J