97 C40TLRX impeller

[Justinskywest]

Was hoping to get a screenshot of the manual for an impeller replacement procedure. Also, could someone point me in the direction of a reliable download source for the service manual? Thank you for your attention

[robert graham]

Google up: Yamaha Outboard Water Pump Service for several good instructional videos of how to do it....very helpful and not a difficult job...

[99yam40]

just for your information, a C40TLRX is a 1999 year model

[cpostis]

The model number you stated (C40TLRX) suggests this motor is a model year 1999, not a 1997. Please review and be sure. In any case, here is a link where you can order the appropriate owners and/or service manual for your Yamaha outboard.

YAMAHA MANUAL STORE


\You can order either of theses at a discount by clicking on the Yamaha Genuine Parts and Accessories link at the top right of this page.

[boscoe99]

There is no specific manual for a water pump replacement that I know of. The Yamaha service manual for your motor has a section that covers the removal and replacement of the water pump but it is broad in scope and short on detail. The Yam SM is intended for an experienced Yamaha mechanic.

Genuine Yamaha SM's are not available on line from Yamaha. You can buy a printed copy for Yamaha or any Yamaha dealer.

Best advice I have found regarding a WP replacement can be found here. Not for your specific model but in general a lot of the information applies.

Water Pump Replacement

You can also do a search on You Tube and find videos that address this topic.

[TownsendsFJR1300]

There is no specific manual for a water pump replacement that I know of. The Yamaha service manual for your motor has a section that covers the removal and replacement of the water pump but it is broad in scope and short on detail.

Very good link but a question. (and this link doesn't address it either)

In the Yamaha shop manual, just about EVERY NUT AND BOLT has a torque spec.

For the water pump housing, the 4 bolts, there is NONE.. Obviously clean threads, maybe some anti-size but no torque #'s.

I've always gone just beyond very snug but why no torque spec's???

Is there a specified torque?

[boscoe99]

Many fasteners within Yam manuals do not have torque values. Why? Crappy data.

So Yam covers their arse by giving nominal values for hardware based on the size of the fastener.

[TownsendsFJR1300]

That makes sense but is BS(from Yamaha).

Their 4 important fasteners that shouldn't be too tight, too loose, etc, and no specific #'s

I'd be curious uses a torque wrench on them and if so, the #, dry, anti-seize etc or just good and snug...

[99yam40]

Not sure on torque values but I believe the WP kit comes with new bolts and they have some loctite on them.
At least for my C40 anyway

so not sure if anti-seize would be a good idea

[boscoe99]

Anyone can measure the water pump bolts and then use the following SM data to determine the torque. This chart says to torque a dry fastener. In certain places within the SM they might specify the use of engine oil.



I doubt many have torque wrenches. Of those that have them I doubt they are calibrated. Of those that have calibrated torques wrenches I doubt that many use them.

[TownsendsFJR1300]

Anyone can measure the water pump bolts and then use the following SM data to determine the torque. This chart says to torque a dry fastener. In certain places within the SM they might specify the use of engine oil.



I doubt many have torque wrenches. Of those that have them I doubt they are calibrated. Of those that have calibrated torques wrenches I doubt that many use them.

I have that chart in both Yamaha OB manuals AND in both my owners and shop manual for the bike.

I happen to have 4 clickers and 1 old beam torque wrench.

Of the 4 clickers, I didn't trust the one and just bought a Snap On 15-75' lb (which costs more than ALL the others put together-$325) just for critical fasteners.

IMO, it's well worth it VS stripping / repairing a hole..

I wouldn't use loctite on those bolts, haven't EVER seen one loosen. Either dry or some anti-seize and little lighter on the torque...

I suppose next time, I'd just go by that chart with just a touch of anti-seize..

[Justinskywest]

just for your information, a C40TLRX is a 1999 year model

You are correct. My mistake. Its a TLRW. I'm just getting the lower unit buttoned back up and we will see how it goes

[Justinskywest]

So i burnt up the new impeller because the cups i was using weren't secure, therefore not pushing enough water to the impeller. I'm waiting on another kit with a housing this time. Should be here Friday. I learned a few things today, regardless of how trivial. Boats are fun

[99yam40]

I would think that the cups would have to fall completely off and you kept running the motor to burn up the pump on that 40.

the cups I use are old and leak a lot of water, and never had any overheating on my C40 much less burn up a pump.

Maybe you have other probelms

[Justinskywest]

I would think that the cups would have to fall completely off and you kept running the motor to burn up the pump on that 40.

the cups I use are old and leak a lot of water, and never had any overheating on my C40 much less burn up a pump.

Maybe you have other probelms

I took the lower unit off and tried two different cups. One pushed water up and the other didnt. It may as well have fallen off