Mercury 2.2 impeller replacement

[tmjb]

I just bought a 1986 and am trying to inspect/replace the impeller because I havee no water coming out of the telltale when running. After removing the prop and the two bolts that retain the cover plate I am having difficulty pulling it off over the propshaft. It comes up about a 1/4" but I can't move it further with my hands. When I try t push it back there is an elastic (springy) resistance. It can be put back to its original postion by tightening the two bolts.

My understanding is that it should just pull straight off.

Any advice would be much appreciated.

Thanks in advance.

 

[seumask]

Are you sure this is where the impeller is on this model, it may be on top of the gear box not behind the propellor.

 

[tmjb]

Thanks for the prompt reply.

Both the parts list and service manual appear to indicate that the impeller is behind the prop.

 

[charles_reed]

I just bought a 1986 and am trying to inspect/replace the impeller because I havee no water coming out of the telltale when running. After removing the prop and the two bolts that retain the cover plate I am having difficulty pulling it off over the propshaft. It comes up about a 1/4" but I can't move it further with my hands. When I try t push it back there is an elastic (springy) resistance. It can be put back to its original postion by tightening the two bolts.

My understanding is that it should just pull straight off.

Any advice would be much appreciated.

Thanks in advance.

You will find the manual here (it's the 2.5 Tohatsu)

http://www.tohatsu.com/tech_info/own_man_pdfs/Toh2-5A2_3-5A2_3-5B2.pdf

The 2.5 has an aluminium waterpump, unlike the SS one of the 3.5.

If left with salt water in it the pump will, unfortunately, corrode.

 

[Lakesailor]

Are you sure this is where the impeller is on this model, it may be on top of the gear box not behind the propellor.

As he has already prised it halfway out I reckon we can assume it's where it should be.

 

[VicS]

My understanding is that it should just pull straight off.

Any advice would be much appreciated.

Yes it should. I reckon it is stuck to the pump body. When you pull the pump body is trying to come with it but prevented from doing so by the impeller.

Maybe get a thin blade, or even tap a wood chisel, between them ??

if you tap it gently and rotate it will that help or will the pump body rotate with it ?

 

[tmjb]

Thanks all for the opinions and advice. I will try seperating them as suggested. I assume I am correct that it is a regular flexible impeller?

 

[tmjb]

Sorry but I have a dumb question (I am new to outboards): I see it says to keep the power head elevated when transporting the engine if not vertical. What happens if you don't?

 

[steve28]

water runs into the cylinder, petrol runs into your boot !

Steve

ps you may have to file the area where the shear pin when through as this can burr and cause the outer bit to bind.

 

[tmjb]

Thanks for both. I'll check on the shear pin and be sure not to lay it flat.

 

[VicS]

Sorry but I have a dumb question (I am new to outboards): I see it says to keep the power head elevated when transporting the engine if not vertical. What happens if you don't?

To stop any water that may not have drained from the leg from finding its way into the engine innards via the exhaust port I think.

Different kettle of fish with four strokes of course where the main consideration is keeping the lube oil in the sump where it belongs and not in the combustion chamber or the boot of your car.

And yep looks like an ordinary flexible vane impeller

 

[dmayes]

Shaft damage

Check the shaft in case there are some burrs where the engine has been running. What feels like small scratches may stop the cover plate coming off. Sanding the outside bit of the shaft with some fine sanding paper may help.

 

[fishermantwo]

Thanks for the prompt reply.

Both the parts list and service manual appear to indicate that the impeller is behind the prop.

I have just bought a later model Tohatsu 2.5. I have not pulled the water pump apart but I'm certain the water impeller is above the "gearbox" in exactly the same place as Johnson 2hp motors etc, certainly not behind the propeller. Matter of fact I see no need to remove the propeller.

Have a look on Utube for Tohatsu/Nissan/ Mercury water pump replacement.

 

[earlybird]

I'm certain the water impeller is above the "gearbox" in exactly the same place as Johnson 2hp motors etc, certainly not behind the propeller. Matter of fact I see no need to remove the propeller.

Have a look on Utube for Tohatsu/Nissan/ Mercury water pump replacement.

If you're referring to the Mercury 2.2 of the OP, I have one of these and the propeller must be removed to replace the impeller.

 

[VicS]

See http://www.boats.net/parts/search/M... UP/GEAR HOUSING ASSEMBLY COMPLETE/parts.html

looks like the impeller is behind the prop to me

 

[fishermantwo]

See http://www.boats.net/parts/search/M... UP/GEAR HOUSING ASSEMBLY COMPLETE/parts.html

looks like the impeller is behind the prop to me

Thanks for the correction. I have just bought it and thankfully don't have to pull it apart.

 

[Lakesailor]

I have just bought a later model Tohatsu 2.5. I have not pulled the water pump apart but I'm certain the water impeller is above the "gearbox" in exactly the same place as Johnson 2hp motors etc, certainly not behind the propeller.

Have a look on Utube for Tohatsu/Nissan/ Mercury water pump replacement.

It's dead simple. If you have F/N it's above the gearbox. If there is no Neutral, it's behind the prop.

 

[tmjb]

VicS was right. The cover plate was stuck to the pump body and so I was trying to pull both out. I seperated them and all is well. I was puzzled though that when pushing the pump body back into the skeg there was a springy resistance. Maybe a seal?

I have several other questions now:

There is a hole on the outside of the prop gear housing, forward and port side of the rounded part in front of the prop. Does anyone know what this is for, should it be open etc. I see it pictured in the manual but can find no mention of it, its function or what to do to maintain it. (I have tried to attach a pdf that pictures it). When back flushing what looked like grease eventually came out followed by a steady stream of water.

I have to replace the ignition coil which comes without the spark plug cap. Does this screw off/onto the HT wire?

The manual tells me to use 92-13783A24 Super Duty Gear Lube. I can't find that but can find Quicksilver Premium Gear Lube (802844Q02) which is 'for all outboards'. Is this OK or do I need to find the 92-13783A24?

Many thanks to all for your opinions and advice.

 

[VicS]

Gear oil. I'd use* any high viscsosity outboard gear oil ... approx sae 80W90
Quicksilver is brand you'll find easily and will be fine.

Cannot help with plug cap. Some do screw on, in which case you'll be able to unscrew it and reuse if serviceable. Some have a coil spring with a spiked hook that pierces the insulation. May not be so easy to remove.

I see no pictures of this hole. If you don't have a Photobucket, or similar, account just resize them appropriately and upload them as attachments ... never mind about pdfs.

I assume you have identified the oil drain and level plugs. If it is a small unthreaded hole it may be just a drain hole to drain all the water from the leg.

(*well, I don't I use ordinary automotive EP90 but it does not contain the the additional corrosion inhibitors that the proper outborad gear oil does)

 

[tmjb]

Thanks again for the prompt reply.

I was trying to attach a pdf from the manual that pictures the hole (but does not describe it). I see that the file size is limited and I can't figure out now how to get it small enough. I have identified the oil drain and fill holes. This is unthreaded and on the opposite side. It may well be a drain hole as you suggest.