1989 Evinrude 15hp Water pumping problem!

Hello Everyone

This is my first post but been reading through many posts and threads to accumulate knowledge.

I am having a problem with my 1989 15hp Evinrude short shaft 2 stroke.

She wasnt pumping any water so have managed to drop the lower unit successfully and replace the impeller (with good info from this site) and installed it in the correct direction with the key in place.

On start up she still doesnt pump any more water. There was a good pee stream for about 3 seconds then dribbles.

I will be looking into any blockages in the pipes but am wondering about a couple of things?



The importance of the water pump housing plate? Should it still pump water without this plate?

There was no gasket between the pump housing and the metal part of the gearcase housing. Should there be one?
I see on a diagram that there should be an impeller plate housing that sits between the housing and the gearcase.

What difference would it make not having one there?
Does the housing rely on a tight seal to maintain water pressure in the pump housing? i am assuming that as the whole gearcase is in the water it shouldnt make any difference to this sealing.


Just not sure where to look next but am gonna pump some compressed air back through the pee hole pipe and up the water tube when i drop the gearcase next time.
Is it difficult to clear the cooling pipes/ducts in the cylinder head without removing the engine block?

Many thanks
Have posted this under another thread in a reply but have been wisely advised to start a new one so here it is.....

Nathan

Re: 1989 Evinrude 15hp Water pumping problem!

It won't work without the plate, the pump rides on the plate, I suspect you will destroy a new impeller without one. The plate has a slot cut out of it to direct water flow to the impeller, I also suspect you'd get no pressure without it.

Do this before anything, i'm telling you right now, without that plate, no water will pump. You don't have a blockage.

Re: 1989 Evinrude 15hp Water pumping problem!

The impeller sits on the plate and you need it or else the water won't circulate properly. I don't think my 15's have a gasket between the housing and the plate so I highly doubt that is causing your problem.
Make sure your muffs or sealing properly or if you can run it in a barrel that would be better.
You can remove the lower unit and shoot water through the water tube with a hose and jet nozzle to make sure there are no blockages.

Re: 1989 Evinrude 15hp Water pumping problem!

Massive thanks for the help guys.

I am ordering a plate today. will let you know what happens.

Cant believe the owner before me left the plate out, or the mechanic. It is now getting me worried what else might be missing or wrong.

There doesnt seem to be a throttle stop screw anywhere either, unless the mixture control dial on the front is used for that purpose too!

Re: 1989 Evinrude 15hp Water pumping problem!

Order the part from your local boat dealer since it will be just as fast and you won't have to pay shipping. If your lucky they will have it in stock.

Was the impeller key present? You need that to lock the impeller to the shaft.

You will have to be more descriptive on your throttle issue.

Re: 1989 Evinrude 15hp Water pumping problem!

impeller key definately present and installed. i checked that first.

When i turn the twist grip throttle right back to low revs the engine idles too low and then cuts out. Was looking at all the throttle mechanisms under the hood to see if there was an idle adjustment screw/throttle stop to screw in and increase the idle speed.

on the front of the engine there is a dial that connects to a needle valve in the carb. diagrams say this is for slow running speed mixture, which does effect the idel speed but not in the way i have seen on other engines with a throttle stop screw. just wonderin if there is a idle screw somewhere under the hood.

thanks again for the replies. This seems to be the best place for help.

regards

Re: 1989 Evinrude 15hp Water pumping problem!

So, i installed the impeller wear plate that was missing and also gave the pipes a blow through with compressed air and they were clear.

Started up the engine to see a powerful stream of water out the tell tale hole.

After a while it became a dribble so fired more compressed air back up the pipe and it sorted it, so there must be a bit grit in there as there was a bit of sand in the lower engine area.

Shes pumping water nicely now.
Just got to get it idling on its own without having to keep the twist throttle open slightly.
Is there a throttle stop screw anywhere that limits the lowest idle speed?

Think i might whip the carb off and give it a good clean out next.

Re: 1989 Evinrude 15hp Water pumping problem!

No, no throttle stop , if I turn mine all the way to the left it will die. Glad to see you fixed it.

Re: 1989 Evinrude 15hp Water pumping problem!

thanks for the info there bktheking, it seems strange that a major engine co like evinrude dont make an engine with a throttle stop and the slow speed mixture adjustment knob doesnt have enough adjustment in it to get it to idle faster.

My 1985 25hp evinrude has a throttle screw on the outside to set the lowest idle speed.

Without the adjust screw it is just gonna cut out and will be annoying to have to keep the twist grip in the right place.

oh well. think the carb needs a clean as it doesnt start very easily when its warm and needs a bit of choke to get it running.

thanks

Re: 1989 Evinrude 15hp Water pumping problem!

They do have an adjustment where the cam roller is, but it has to do with timing. My 83 9.9 has a slow idle screw but they eliminated sometime in the late 80's. My slow idle adjustment knob is broken so it shuts off when I turn it all the way. But at the same time if something in the electronics were to go and my stop switch wasn't working this makes for a good back to shut it down.

Re: 1989 Evinrude 15hp Water pumping problem!

Hey guys, me thinks the throttle low speed adjustment is in the end of the throttle grip handle on this year model.

Re: 1989 Evinrude 15hp Water pumping problem!

You are correct sir, knob on the end.

Re: 1989 Evinrude 15hp Water pumping problem!

Yep, this year has the cable throttle and the adjustment is a cable tensioner on the end of the throttle handle.

Re: 1989 Evinrude 15hp Water pumping problem!

Hi
Do you guys mean the throttle idle adjust is part of the safety cut out switch in the very far end of the tiller/twist grip?

I hadnt thought of looking there?!!
thanks

Re: 1989 Evinrude 15hp Water pumping problem!

Yuppers!