Tohatsu 3.5 blocked piddle pipe

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StephenW

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Found my piddle pipe on the Tohatsu 3.5 (2 stroke) just dripped a bit yesterday and is now not dripping at all. Is there an easy way to check for blocking/unblocking of water cooling system?

Someone has suggested blowing compressed air up the piddle pipe - is this feasible or is it likely to just blow off the connection with wheever metal is inside?

Poking wire up the piddle pipe - is this kosher? Any recommended type of wire?

The unit is about 6 years old but very lightly used and in generally good nick - so I'm reluctant to lose it to overheating. Fortunately its only used for about 10-15 minutes at a time so hopefully no damage so far.

This year there's been a lot of fine green hair-like weed and I wonder whether this is inside.

Alternatively it could be the impellor I suppose, but I'd be surprised if so - do they go very often and how do you set about replacing?

All (informed) advice appreciated - cheers
 
Same vintage as ours. same problem- If you've been in shallow water-salt/mud/weed can block it- try 1) reverse flushing piddle with hosepipe, 2) flush via big water intake/ outlet below cavitation plate. Be prepared to get wet for 10 min doing it /forums/images/graemlins/grin.gif

Compressed air good if you can access it- professionals use it- don't get wet.
Poking a bit of plastic covered wire- avoid if you can, can't reach the blockage unless in the rubber pipe.

If it doresn't improve, the channels in the cylinder head may have become clogged with salt n stuff- get head removed and clean them out.

Try to flush it regularly with fresh water to stop the salt build up in the channels in the cylinder head.

Enjoy /forums/images/graemlins/smile.gif

You should change the impeller annually or when you winterise- they has a hard life. If flushings above dont work- thats your next stop- but you need the rotor and the plastic case as well, I think, as case gets damaged in removal- so try flushing first.
Also piddle can be slow when warning up, then gets going under load. Is this the case?

Hope this helps.
 
Yes poke the pee hole out with a bit of wire. Bit of thin electrical wire, paper clip whatever.
If that does not clear it then look at where it connects to the engine. Presumably there is a bit of plastic hose from the pee hole fitting to a fitting on the engine. If so disconnect the hose and poke out the fitting at the engine end. Take care when removing the hose and refitting it as the fitting on the engine is probably plastic and may not be very robust.

After 6 years, irrespective of the amount of use, you should be considering an impeller replacement but you may have the internal waterways clogged up.

Hopefully it will be just the peehole.. A blocked pee hole will not cause overheating though, it is just an indicator that the pump is working OK. Spit on the cylinder head. If it sizzles then you have other problems but if you can touch it and count to three then it's probably OK

Dont know the engine so cant advise on the impeller replacement. I guess a 3.5 has a clutch even if not reverse gear. If it has a clutch the water pump will be on the top of the gearbox (as opposed to behind the prop) and driven by the vertical drive shaft so it will entail separating the gearbox from the leg. A manual is advisable unless you are like me.
 
Thanks for relpies.

Piddle normally starts straight away and is reasonable stream rather than a drip.

Total lack of any flow now-which is the concerning bit.

If anyone is familiasr with this engine appreciate hearing any other thoughts and indication of where impellor is located and degree of difficulty replacing. I'm fairly mechanically minded and generally manage to tackle things OK but since this is all located near the gear leg I'm a bit unsure what to do.
 
Just treated same problem on mine on Saturday.

When I originally bought the motor it had same problem, I stripped it down to check the water chambers which were clear and replaced the pump impeller.

Flow stopped fairly soon again after and went to just a drip. I cleared it this time using a piece of copper wire.I found it necessary to remove the side of the outboard and remove the rubber pipe. It turns through 90 degrees where it is attached to the nipple coming out of the engine. Having done that I had a gentle poke around with the wire which seemed to clear the obstruction, how long it stays clear remains to be seen.

I believe it is only a tell tale, and that the bulk of the cooling water goes down inside the leg, I could not work out why the engine was running cool with what I thought was the water exit blocked until I stripped it down. There was something hard either salt or paint restricting the inside of the rubber pipe as well.

The other problem I had was that the motor was difficult to steer with. I had to have the friction adjuster too tight to turn the motor or it jerked around on its own. I removed the motor from the bracket and cleaned the shaft, bushes and fixing plate and greased it all lightly with silicone grease, what do other people do?
 
[ QUOTE ]
attaching a car foot pump

[/ QUOTE ] Not many people carry a car foot pump with them I suspect!
 
My 3.5 had a meal of Portsmouth Harbour mud and got severe indigestion last year. Fairweather Marine degunged & serviced it with a new impellor & new anode for about £80. For that, I don't reckon it's worth me getting involved - I'd probably do more damage 'cos Im not familiar with the beast's innards.

On that basis, if taking the pipe of & cleaning it and the outlet doesn't sort it, I'd let someone who knows what they're doing have a look.
 
When I bought my boat the outboard had just been "serviced" by a dealer (I had the receipt). The first time I used it I had cooling problems and found that the impellor had completely disintegrated.
Since then I won't let any dealer anywhere near the thing.

At least I would know who to blame if it let me down. More importantly I am more likely to be able to fix it when I'm miles from anywhere.

Taking the head off and clearing the waterways is not a difficult job.
 
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