Mariner 3.3 tell tale

simonafloat · 06 March 2016, 15:10

Hi all

Leading on from my small auxiliary engine post. Got the mariner 3.3 fired up in a bucket this weekend. It's the little gearless 2 stroke tohatsu/mercury/mariner engine. Not a lot of water through the tell tale at low revs, plenty at higher revs. Impeller is fine. I remember a few years back the flow was pretty much the same regardless of revs. Cleared the tell tale of crud initially with a piece of wire. Would a weak stream at low revs be acceptable?

Cheers all

Simon

Fenlander · 06 March 2016, 15:18

When I had similar last year with an old Mariner 4 which otherwise looked great condition I did all the usual revving in a bucket, prodding and checking impellor to little avail. An investigation of the engine cooling passages soon found the problem...

simonafloat · 06 March 2016, 18:16

Quote:

Originally Posted by Fenlander

When I had similar last year with an old Mariner 4 which otherwise looked great condition I did all the usual revving in a bucket, prodding and checking impellor to little avail. An investigation of the engine cooling passages soon found the problem...

Hmm.. ok, I am cash poor but time rich at the moment. Maybe a strip down? Any advice on how easy this is? Will I need to buy any new seals or gaskets to reassemble? I fancy having a tinker with this engine. It was the best purchase I think I ever made from a cost/fun angle. I bought it 20 years ago for 90 quid and it was used almost every day for the 15 years I lived afloat on the Thames. We even shifted a houseboat with it once.

Fenlander · 06 March 2016, 18:59

I don't know how similar the 3.3 is to the 4, I guess the parts diagrams will indicate this. The gaskets for mine were unavailable so I was careful with the old one and refitted with a thin smear of compound on one side.

A1an · 06 March 2016, 19:43

My Mariner 2.3 was identical to yours

Just a dribble at idle but a decent flow at revs. Never caused an issue.

jeffstevens763@g · 07 March 2016, 06:53

Quote:

Originally Posted by simonafloat

Hi all

Leading on from my small auxiliary engine post. Got the mariner 3.3 fired up in a bucket this weekend. It's the little gearless 2 stroke tohatsu/mercury/mariner engine. Not a lot of water through the tell tale at low revs, plenty at higher revs. Impeller is fine. I remember a few years back the flow was pretty much the same regardless of revs. Cleared the tell tale of crud initially with a piece of wire. Would a weak stream at low revs be acceptable?

Cheers all

Simon

Simon how hot does the water get at tick over if just warm should be ok but at 20 years old i would strip as fenlander did cost of gaskets or make your own, at £90 she deserves a bit of TLC what a bargain.
my Suzuki 90 had what i call a progressive tell tale @ 160 hours mechanic said it was ok just for info
cheers

simonafloat · 07 March 2016, 19:20

Before I start stripping the engine, I read this top tip, not sure if it's worth trying? - Turn the outboard upside down, pump vinegar into the telltale until it comes out the other end, leave it overnight then flush the dissolved crud out, then repeat. Worth a try? Kind of makes sense to me and vinegar is very cheap.

C-NUMB · 07 March 2016, 19:29

There are 2 types of impeller designs on this type of engines( 2,3- 3,5 Tohatsu, Nissan Mariner, Mercury all the same engine). One with the impeller on the shaft and another on the propeller axle. The later has IMHO less powerful tel tale on slow rpms. In front part of the casing of the lower gear there is a chamber collecting very easily mud over time, that is also wort cleaning(now don't remember was this relevant on both models though). The vinegar thing is worth a try also.

simonafloat · 07 March 2016, 19:50

Quote:

Originally Posted by C-NUMB

There are 2 types of impeller designs on this type of engines( 2,3- 3,5 Tohatsu, Nissan Mariner, Mercury all the same engine). One with the impeller on the shaft and another on the propeller axle. The later has IMHO less powerful tel tale on slow rpms. In front part of the casing of the lower gear there is a chamber collecting very easily mud over time, that is also wort cleaning(now don't remember was this relevant on both models though). The vinegar thing is worth a try also.

Yes, mines got the impeller on the propeller axle. I'm going to fire her up again this weekend and check the water temperature. Bigger bucket required! The one disadvantage to having a fixed gear... harder to run in a bucket..l

A1an · 07 March 2016, 20:46

Quote:

Originally Posted by simonafloat

Yes, mines got the impeller on the propeller axle. I'm going to fire her up again this weekend and check the water temperature. Bigger bucket required! The one disadvantage to having a fixed gear... harder to run in a bucket..l

Pull the split pin and whip off the prop.

simonafloat · 09 March 2016, 21:28

I've decided not to faff around and am planning on taking the engine apart to clean it properly. Anyone taken this one apart?
http://www.alamaula.com/a-barcos/flores/motor-mercury-force-3-hp/1001145339110910435091809

It's a force but it's really a tohatsu

simonafloat · 11 March 2016, 08:03

Quote:

Originally Posted by simonafloat

I've decided not to faff around and am planning on taking the engine apart to clean it properly. Anyone taken this one apart?
http://www.alamaula.com/a-barcos/flores/motor-mercury-force-3-hp/1001145339110910435091809

It's a force but it's really a tohatsu

Anyone? I am going to start taking it apart tonight and I don't want to undo more than I need to ! Cheers

Fenlander · 11 March 2016, 09:50

So you've established yours is the type with the impellor on the prop.

The elements to the water flow are... The pump and impellor itself... the water feed pipe to the power head... the waterways in the power head.

You say you've checked the impellor end.

Sometimes taking off the lower gearcase and flushing up the pipe in the leg and back down from the pee hole alternately can have some success (with some sort of reducer on a garden hose but do not over pressurise).

However in my experience any deposits are often in the powerhead water jacket itself and flushing alone won't remove completely.

On my 4hp pictured a few posts above there was an exhaust side plate that gave access to the water jacket passages together with removing the head plate.

But on yours I think the only access is to remove the head where you will see the waterways which can be poked/flushed out. Then flush up from the impellor end of the pipe in the leg.

I have a manual that includes the 2hp which is near identical to the 3.3hp and I've attached two images of the alternative arrangements. The manual assumes you will want to remove the whole power head which involves removing the pull start and flywheel. I'd hope you will be able just to take the head section off.

So if it were me I'd take off the prop and impellor housing, take off the head, poke out deposits from the head water jacket waterways and flush up from the water pump end.

Obviously take huge care removing the head bolts to avoid snapping. Tapping hard on the bolt head, blowtorch heat & WD40... plus only moving half a turn... more W40 then turn out a bit more... and repeat to avoid disaster.

jeffstevens763@g · 11 March 2016, 10:10

dont want to be a kill joy 20 year old engine taking head bolts out i know you said you dont want to faff around but if the head bolts shear you will wish you had.
you say you have low flow at low revs ok at high revs so why not run the engine with salt away to see if it improves.
one thing to consider your running in a bucket is there enough head on the pump for it to pick up enough water at low revs in other words the head of water assists the pump.

Fenlander · 11 March 2016, 10:29

It's a fair point Jeff. I was happy to "gamble" on the bolts with my 30yr old Mariner 4 and it paid off... but it can go the other way.

jeffstevens763@g · 11 March 2016, 10:41

its just he has flow all round so if it were me i would think its not that serious as it stands but i do know my suzuki would have water over the cav plate and not pump but give it two more inches and it was fine, and slow at tick over increasing with revs, now the 25 is different pumps well all the time. everything you have said spot on and may be it is a strip down in the end but i would faff a bit first before committing to a full blown stripdown.

cheers

simonafloat · 11 March 2016, 15:26

Thanks for the advice guys. Since this morning I've come down with man flu so may not be doing anything at all this weekend.

Trying to salt away does sound worthwhile, where's the best supplier? If I'm going to get some I should definitely use it on my mariner 15. I see it comes in a kit with an in line hose pipe attachment, is it possible to just put some in the bucket? It'll have to wait for a few weeks as I literally don't have two pennies to rub together at the moment.

Up until recently I thought that flushing with fresh water after each use would be sufficient to keep an engine corrosion free.

jeffstevens763@g · 11 March 2016, 17:42

Salt-away have an eBay shop Simon

Cheers

simonafloat · 15 March 2016, 14:49

Ok well I went for it today and took the lower part of the leg off, followed by the power head. No problems with removing the 6 powerhead bolts. It was all very easy really.

There was a fair bit of salt and sand but no total blockages. I didn't remove the cylinder head. I cleaned out most of the salt and then reassembled the power head and reverse flushed through the tell tale using a steam cleaner. Worked a treat. Unfortunately I do need a new power head gasket before I can do it back up permanently. The existing one came right apart when I pulled the head off.

Having seen the inside of this little engine I would say that just regularly reverse flushing though the tell tale, perhaps with salt away, is all it should need.

Cheers for all your advice, she'll give 20 more years service I reckon

Simon

simonafloat · 16 March 2016, 14:26

Quote:

Originally Posted by simonafloat

Ok well I went for it today and took the lower part of the leg off, followed by the power head. No problems with removing the 6 powerhead bolts. It was all very easy really.

There was a fair bit of salt and sand but no total blockages. I didn't remove the cylinder head. I cleaned out most of the salt and then reassembled the power head and reverse flushed through the tell tale using a steam cleaner. Worked a treat. Unfortunately I do need a new power head gasket before I can do it back up permanently. The existing one came right apart when I pulled the head off.

Having seen the inside of this little engine I would say that just regularly reverse flushing though the tell tale, perhaps with salt away, is all it should need.

Cheers for all your advice, she'll give 20 more years service I reckon

Simon

Just a final question, while I wait for my new gasket to arrive. Does the gasket need bedding in on any kind of compound when I fit it? I can see that it's not subject to any great pressure but I don't want it leaking.