'67 Merc 110 9.8 No water pumping

[comptechie]

I have a '67 (ish) Merc 110 9.8 HP OB. I bought it last year and ran it a few times. This year a few months ago I start it up to make sure everything is going ok. When it starts there is no water coming out of the spot its suppose to. So I figure it's the impeller.

I take apart the lower and the impeller actually looks alright. I go ahead and buy a whole water pump kit, the housing, impeller, keyway, etc. Put it all back together and still not water pumping through it. I can blow in the top hose and get bubbles coming out the bottom, so I know it's not clogged. When I drain the oil I notice that water and the lower oil is mixing. So I figure maybe the copper tube is not sealing with either the pump or the head. So I silicon the crap out of it... Start it up... still the same thing. No water pumping. I do notice though that there is a little bit of exhaust coming out of the hose where the water should be coming out of. I am not for sure what that means. Any one have any suggestions or ideas what could be going on?

Thanks in advance!
Derek

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

Someone at work said it could be a head gasket.

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

Bump

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

bump

 

[bob1340]

Re: '67 Merc 110 9.8 No water pumping

I do notice though that there is a little bit of exhaust coming out of the hose where the water should be coming out of. I am not for sure what that means. Any one have any suggestions or ideas what could be going on?

Thanks in advance!
Derek

If the water and oil are mixing it could be the seal at the bottom of the pump is shot. I'd remove the lower end and reseal the whole deal. It's pretty cheap to do on those motors. The bottom and top water pump housings have seals on them. The bottom seal is between the pump and gear box. The top seal is between the pump and the exhaust/water housing. If either of these are shot the pressure of the pump is probably mis-directing the water. Also, make sure you have the impeller in the correct way.

I'd say you have seal problems. Easy/Cheap fix.

The plastic tube thing is not a seal but a guide. The pump top housing has a rubber seal in it for the copper tube to fit in, the plastic tube merely guides the copper tube to it.

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

Thanks for the info. However the whole water pump (impeller, housing, seals, and gaskets) have been replaced with brand new ones. Even if there was a small leak down there, shouldn't I be getting at least some water pumping through the head?

 

[bob1340]

Re: '67 Merc 110 9.8 No water pumping

Thanks for the info. However the whole water pump (impeller, housing, seals, and gaskets) have been replaced with brand new ones. Even if there was a small leak down there, shouldn't I be getting at least some water pumping through the head?

Look at this diagram close.


http://www.crowleymarine.com/mercury-outboard/parts/398_170.cfm

#'s 30, 31,and 16 are the main culprits along with 10 and 12

You replaced the top and bottom pump housings? # 29 and 38?

If the water is in the oil you have a problem with sealing someplace.

Remove the lower end and place it in a tub of water. Spin the shaft with a drill and see if it pumps and where the water is coming out at.

Does the top housing have a large rubber seal in the neck the plastic tube fits in?

The copper tube seal is #39 in the diagram.
The guide tube is # 45 The guide tube has nothing to do with sealing anything. #39 does and if it ain't there or not mounted correctly the pump won't get water to the motor. Also, I suggest against silicon on anything here. Be very careful with it anyway.

Looking down at the impeller from the top are the blades curved to the left?

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

Just went out and disassembled the lower again. Here are the best pictures I could get of it.

I am pretty sure #'s 31 and 30 came with the kit that included the housing. So those seals should be good. Number 10 and 11 are good, and even if one of the two were not, I am sure I would still see some water going through the head. That really only leaves # 16 on the link provided. Yes I replaced both the bottom and the top housing. This is the kit I bought:

Sierra International 18-3447 Marine Water Pump Kit for Mercury/Mariner

I didn't have everything handy to try the drill idea. I can try that if needed, but let me know if the rest of the information, or pictures help shed some light on the issue. I REALLY appreciate your help, I have been taking my little jon boat to the lake with my 32lb trolling motor, and it sucks taking half an hour to get across a small fishing lake. Can't wait to get this thing fixed.

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

Ok, so I was able to do the bucket test with just the lower and a drill. I also had the copper tube attached to the pump. It worked! Water flowed freely out of the top of the copper tube. So that means that all the seals down below are doing their job. So does that mean it's something in the head?

*EDIT* Also I mentioned this before, I just still think it's weird.. I AM getting some exhaust blowing out of the line where water should be coming out of.

 

[bob1340]

Re: '67 Merc 110 9.8 No water pumping

Just went out and disassembled the lower again. Here are the best pictures I could get of it.

Okay, you put a new seal under the tube in the picture above? The tube is just a guide, but the copper tube that goes to the powerhead seals by the rubber seal that should be under the plastic tube.

Being I am to understand you removed the copper tube from the motor, are you sure it is going back in correctly?

And if the gear oil and water are mixing you still have a problem with a seal someplace.

Ok, so I was able to do the bucket test with just the lower and a drill. I also had the copper tube attached to the pump. It worked! Water flowed freely out of the top of the copper tube. So that means that all the seals down below are doing their job. So does that mean it's something in the head?

Not necessarily. Your pump can still pump water up the tube but be leaking into the gear case at the same time. The motor may stay cool, but the gear case won't last long. The seals under the pump are to keep water and oil in separate areas. The seal at the copper tube that goes up to the motor has to be good.

*EDIT* Also I mentioned this before, I just still think it's weird.. I AM getting some exhaust blowing out of the line where water should be coming out of.

By the line I am thinking you mean the tell-tale or pee hole correct? The water that goes into the motor exits via the exhaust and the tell-tale. So I am guessing if no water is being pumped up to the motor exhaust would be free to exit the tell-tale. Other than no water the motor runs good or bad? Good power?

If you pull the bottom off again (lucky it is so easy to do on these!) you can attach a hose to the copper tube heading up to the motor. Get it sealed to the tube as good as you can. Turn on the water hose a little and see what is happening. Is water coming out the exhaust but not the tell-tale? If so the tell tale may be plugged, but being you have exhaust coming out of it I doubt that. If the water is not coming out of anything you have some issue with the water jacket being plugged. I don't like using silicon on these for that reason. A chunk of it can go up and plug something up. I have never used it, but I think there is a flush valve on the rear of the motor. I have one on my 1970 7.5 motor. Maybe try back flushing it?

Good luck with this and keep us posted.

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

By the line I am thinking you mean the tell-tale or pee hole correct? The water that goes into the motor exits via the exhaust and the tell-tale. So I am guessing if no water is being pumped up to the motor exhaust would be free to exit the tell-tale. Other than no water the motor runs good or bad? Good power?

The motor runs great, I am just afraid to run it with no water going through the head. I have watched videos of this motor from various places on the web, and water should be coming out of the pee hole. I know the bucket test with the lower worked, but that doesn't mean that water is going through the head. I am afraid to run it unless I know 100% that water is running through it.

Pee hole where water *should* be coming out of:

The tube that leads to the pee hole:

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

This video:

http://www.youtube.com/watch?v=GAqsapPFAq0

at around 36 seconds you can see what I am talking about. Water is coming out of the hole as it should. Mine does not do that... I just get a little bit of exhaust coming out of that hole...

So since I did the lower test with the drill, and I DID get water coming up to the top of the tube, that means it has to be something in the head right?

 

[bob1340]

Re: '67 Merc 110 9.8 No water pumping

This video:

http://www.youtube.com/watch?v=GAqsapPFAq0

at around 36 seconds you can see what I am talking about. Water is coming out of the hole as it should. Mine does not do that... I just get a little bit of exhaust coming out of that hole...

So since I did the lower test with the drill, and I DID get water coming up to the top of the tube, that means it has to be something in the head right?

Its something. Like I said before, pull the lower unit and attach a Garden hose to the copper pipe. Turn on the water and see what is going on.

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

I have already taken a mouth full of water and was able to successfully blow it from the head and the water came out of the bottom (where the water normally goes into the lower).

It would be tricky to get a water hose to hook up to the top of the copper tube, as the water hose is a lot bigger than the tube, and I don't have any fittings or anything. But a mouth full of water did the trick.

 

[huntin dawg]

Re: '67 Merc 110 9.8 No water pumping

Looks like you did way more work than you needed to. Your exhaust cover gaskets are blown. That's why you have exhaust coming out the pee hole instead of water. Replace those and you'll be good to go.

HD

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

Awesome, I'm a boat motor noob, but I figured it had to be something like that. Everything else checked out. Do you have a part number, or maybe in the diagram linked above you can point out where that is. I don't even know where to start. Is it in the head, lower, etc.

Thanks Again!!!

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

Ok, I am pretty sure I have it figured out. After attaching the copper tube to the head and blowing it was pretty obvious that I had missed a gasket in my search. Here is an image of what I found after some disassembly:

The gasket (specially where the water goes into the head) is completely tore up. Anyone know a good place to get this, also get the seal (if there is one) where the copper tube meets the head?

Thanks again for everyone's help. Without your ideas, and suggestions I wouldn't have been able to figure this out as quick.

 

[bob1340]

Re: '67 Merc 110 9.8 No water pumping

Awesome, I'm a boat motor noob, but I figured it had to be something like that. Everything else checked out. Do you have a part number, or maybe in the diagram linked above you can point out where that is. I don't even know where to start. Is it in the head, lower, etc.

Thanks Again!!!

Here is a link.


http://www.crowleymarine.com/mercury-outboard/398.cfm

I'm thinking is stuff in cylinder block, probably #31 and #33?

And yes, if that gasket is blown exhaust will probably come out the tell-tale, but I don't think it would stop water from going up to the block.

Also, if you think you have a water leak into the gearcase take care of that as the water will ruin the gearbox and render your old motor useless.

EDIT: Sorry for the confusion with the #31, #33, those are the gaskets to the side plate. The seal at the bottom end is a 36558. I am wondering if that's the same for the top? I can't find it otherwise.

 

[starcraft1982]

Re: '67 Merc 110 9.8 No water pumping

by the pics,it also looks like you didnt put the new impeller in.the fins on those go straight out to sides.notice that one in pic all the fins are arched?replace the impeller or after you figure everything out,youll still end up w/problems and another pulling of the lower!

 

[comptechie]

Re: '67 Merc 110 9.8 No water pumping

by the pics,it also looks like you didnt put the new impeller in.the fins on those go straight out to sides.notice that one in pic all the fins are arched?replace the impeller or after you figure everything out,youll still end up w/problems and another pulling of the lower!

It's a brand new impeller specifically for this model. The old one I pulled out wasn't in bad condition and it looked exactly like this one. Also when googling images of the impeller in the casing the images looks the same as mine.