mariner 3.3 water pump

[Mandarin331]

Just tried the outboard and found that there's a very low volume of water coming out, and no increase as the throttle opens.

I searched for (and found) a user manual on this forum, which helpfully says 'refer to your dealer'.

I tried to remove the lower gearbox but there's something stopping it from sliding off, even after loosening the gearshift connection.

Can anyone give me some advice how to check the impellor and water system please?

Thanks
Neil

 

[VicS]

You've got to get the gear case off to access the water pump I'm afraid. If you have undone the clamp between the upper and lower shift rods and removed all the bolts (2?) then its probably the drive shaft stuck in the crank shaft. Don't know of any tricks to separate them if they are rusted together.

Parts diagrams available HERE might be of interest

If no help from here try posing on the Mercury/Mariner board at iBoats

 

[Mandarin331]

Thanks for the advice. You gave me the confidence to pull harder and it came off eventually. The impellor seems to be fine, all the water channels seem OK and clear.

I'm a bit concerned that if the impellor is fine there must be a problem elsewhere, are there any other parts of the cooling system I can check?

 

[VicS]

Don't refit the old impeller now you have gone to the trouble of dismantling it. Fit a new one. Might also be worth renewing seals while you have it off.

Connect a hose to the water tube and see if you can get a flow then. Should come out of the pee hole at least but you should get a flow down the leg as well.
(I don't think there's a thermostat but as I dont know the exact model I am probably not looking at the right diagram. If you can locate one take it out while you do the above. Also test it to make sure it opens)

Make sure the pee hole fitting and hose are not blocked!

Small outboards are notorious for getting the cooling systems clagged up, especially if not flushed after use.

 

[catalina1]

Hi
Ive just done the impeller on my 3.3
The impeller has a small roll pin against the flat on the shaft.
Make sure this roll pin ( key) is in place otherwise the impeller will not go round with the drive shaft!! hence low water flow.
Worth a good look.

 

[najsmith]

Couple of questions.

I have sucessfully (i think) replaced the impeller in the pump assembly, run a coathanger up the pee pipe and the copper pipe and managed to get the copper pipe in the shaft back into the pump as well as drive shaft back into the engine head, but nothing came out of the pee tube; well I saw an occasional drip building and then falling, but not the constant stream I'd expect.

On removing the lower assembly I think i noticed some water drain from the copper tube, so It feels like the new impellers doing its job.

1) Any suggestions on where I should look next? I always have run it in fresh water after trips but suspect some silt may have built up over time. I have no idea how to proceed once the cowlings off.

2) If I connect a garden hose to the bottom of the copper pipe, should I expect to see a steady stream of water out the pee hole - does it matter if the engines running at this point?

3) How can I clear the waterways between the copper pipe and pee hose. Is there a product I can use? A compressed air spray targetted down the Pee hose?

4)Any top tips for reassembling the lower section with the engine head. Trying to line up the copper pipe and the shaft head took absolutley ages - any tips for getting it back together and rejoining the gear linkage thru the side. I felt I was playing a game of operation!

Coments and thoughts appreciated

 

[VicS]

A good idea to connect a hose to the water tube. No you don't want the engine running. You should get water out of the telltale and slso down the "leg".

If it turns out to be completely blocked a strip down ( head off anyway) may be necessary otherwise pumping an acid descaler such as Rydlyme or Fernox DS3 boiler descaler or even a well diluted hydrochloric acid based brick and patio cleaner through might do the trick.

Bit of a fiddle I suppose lining things up. Even worse with a single piece shift rod that has to be lined up too. Turning the flywheel may help to get the drive shaft engaged with the crankshaft. Gets easier the more times you do it.
( the first time I rebuilt one it suddenly all slipped into place ... took it apart again to make sure I had not broken anything!)

 

[najsmith]

Sorry VicS - I've been away, but we're back on the water and I'm getting sick of having the outboard in peices & borrowing the father-in-laws, when mine runs more reliably, even if it doesnt cool...

I plan to purchase some Rydlyme Marine http://www.expresslube-shop.co.uk/s...scaler.html?shop_param=cid=12&aid=RYD-1000-5&

Not sure how I could pump it into the system. Would it be OK to turn the outboard unit upside down (with the gear box off) and pour this stuff down the copper tube that feeds water from teh pump, and leave over night?

Not quite sure how I would "pump" it through the system. But right now, I'd like to avoid taking the head off, because (a) Im a coward and (b) well, see (a)

 

[VicS]

Turning it upside down is not a good idea. Unless very careful you could get the cleaning solution into the cylinder via the exhaust.

There is a diagram on one of the Rydlyme websites showing an outboard being cleaned by running it in a barrel of Rydlyme solution. The trouble is though it only reaches the areas it can already flow through. Any parts completely blocked remain so.

I think your engine is a re-badged Tohatsu. If so there is a workshop manual on Lakesailor's server that might be useful http://www.lakelandimages.co.uk/Forum pics/info_engine/Tohatsu/

Also somewhere some pictures of a similiar engine stripped down for descaling. If he is around perhaps he will point to them.

Don't go exploring his site on the office computer.

 

[davidbfox]

Be prepared for a terribly frustrating fiddle trying to reassemble driveshaft, gearchange shaft and water pipe (if it is the version with a gearchange) through the small inspection hole.

I found a bit of string round the pipe and bent wire allowed me to ease everything into place with the aid of my wife's small finger.

The drive shaft slots in about 1cm before the gear, then the waterpipe. Vaseline on the water pipe helps.

If you lift the shaft up out of the gear case to look at the impellor, which is really easy to do, the drive gear falls off into the gearcase and rattles, which it did not do before. And there is no drive but you have used up the oil in your squeezy pack! To replace the gear you have to pluck up courage then take off the cover behind the propellor. In fact once you have decided to do it it is dead easy. The gear then just slips onto the drive shaft.

Not wanting to waste the nice fresh oil (and when shops are shut at 10.00pm) I discovered that you can refill the squeezy pack using a drinking straw as a pipette. Having to have the engine working by next day for a limited launching slot adds to creativity.

Good luck.

 

[najsmith]

Water Pumps

Yes - I have failed to get it all connected in the past (been on the bench for 6 months) but am determined to reattach Leg to engine.

I think my next step, after profing everything stops/starts/turns as desired, will be to remove the 6 bolts beneath the block and remove the engine head to take some wire brushes and rydeline stuff to the water channels..

Bent wire, string and wifes finger all good tips - will clear some space in the shed & crack on... Report to follow in a few weeks

Thanks Guys

 

[Lakesailor]

The two arrows to the left show the water channels. The two to the right show the rather small holes through to the head. These need cleaning out and I reamed them a bit bigger. The next drill size up (in a slow drill) would do the trick. You can physically poke out most of the gunge.

The lack of a pee stream doesn't mean the water is not circulating. It may just be the elbow the pee steam pipe attaches to is blocked.

 

[najsmith]

Pee stream

Indeed. I have tried coat hanger wire up the little black pipe and that seems not to have acheived much, but perhaps I need to remove the tank and get closer in, so I can remove the black pipe and inspect the elbow joint.

First things first.. I need to get that leg on and I fear much muttering, huffing & puffing will take place in the shed before thats sorted!

Im trying to imagine the smug sense of self satisfaction after I've fixed this sucker, to help motivate me to crack on...

 

[davidbfox]

A couple more tips:
1: have a helper
2: a strong light
3: make sure you have removed spark plug so you can turn engine easily by hand with the pull start or more directly onto the bit that spins on top of tthe engine
4: when you start, the driveshaft will be attached to the gearbox sticking out the top about 60cm. Practice holding it up the middle of the leg and feeling for the obstruction as it engages with the splines at the top; if it doesn't engage easily turn the engine a bit and suddenly it will slip into place. Getting the feel of how it lines up makes the next steps easier.
5: before putting gearbox back on make sure that turning the shaft does turn the prop when gear is not in neutral, and nothing rattles. If it does rattle the little gear has fallen off the end of the shaft. You would then have to remove plate behind prop to put it back on. Also make sure the impellor is firmly attached to drive shaft with the little pin in place so it turns with the shaft. Checking these things at this stage saves having to do it all again later.
6: Don't overtighten the bolts holding the pump body on as the housing can crack.
6a: lubricate the end of the water pipe
7 : use string + wire through the inspection hole so that you can both pull the water pipe towards you and push it away as required.
8: gently slide gearbox and shaft onto the leg aligning each bit one at a time. You don't have to get all three bits completely aligned simultaneously.
9: the driveshaft will engage first, then the water pipe after about 1cm of movement, then the gearchange shaft. The hardest to align is the water pipe.
10: Make sure that the little clamp bolts that attach the gearshift rods together aren't too loose. If one falls off you have to take the whole thing off and start again. I found that a bit of bent coathanger wire lets you hook the clamp through the inspection hole so you can line everything up. The manual says that you should ensure that the gearbox is in neutral and so is the gearshift on the top of the engine.

After all that it's not that difficult if you are patient. You are not going to make anything worse. Print off the manual and read before starting.

As mentioned on post above the manual is on lakesailor's site and it's a brilliant resource backed up by photos.