Ultrasonic cleaners - Evinrude 70

[dpround]

I'm still struggling with the Evinrude 70 (old, late '70s?). It idles fine and will go for a bit, but then the revs drop off as fuel starvation sets in. It is possible to make it go by pumping the primer bulb furiously - we are talking serious effort here. I have bypassed most of the fuel system and fitted an electric pump with no change. I think there must be a blockage in the carbs. Looking online, they may be prone to it. Carb kits do not normally fix it, but new carbs do it seems. Anyway, I have resolved to do as detailed and complete clean of the carbs as I can ... and so now to the question

How good are ultrasonic cleaners? I am fairly convinced that they will leave the carbs looking like new, but will they clean out blockages? At the moment I plan to attack with a carb cleaner spray, an airbrush cleaner kit (lots of mini bottle brushes and widgets for cleaning tubes) and some patience.

Advice welcome!

I could buy three new carbs for £300 - pretty steep for such an old engine, but...?

Many thanks

David

[steco1958]

£300, compared to £?????

I would buy the kit !!

[jeffstevens763@g]

ultrasonic cleaners are very good if you use the correct cleaning fluid we use them to clean our diving hats you can get a carboreter cleaner for £120.00 but if you have £300.00 you know their good to go if brand new.

cheers

[Pikey Dave]

I have a Walkers ultrasonic bath. I got one of the "cosmetically damaged" ones. Had it over 10 years now & it's saved me a fortune in diving gear servicing. As Jeff says, you need the correct fluid for the job. All that said, I'd probably go for the new carbs. Try Mike Vincent at South Coast Marine in Christchurch. What he doesn't have isn't worth having.

http://www.walkerelectronics.co.uk/p...sonicbaths.php

[office888]

I use a mixture of household cleaning vinegar and 99% isopropyl alcohol when cleaning carbs in my ultrasonic.

The alcohol degreases and dissolves most varnishes, the vinegar will destroy most corrosion.

[Pikey Dave]

For diving gear I used a teaspoon of citric acid powder & a dash of washing up liquid.

[dpround]

Thank you for the advice. I think my summary is that an ultrasonic bath might do the job, but it is not as cheap as I thought, which makes the new carbs possibly the better bet as they are a pretty sure fix. I think I'll have one last go manually cleaning them and then give up and spend the money.

All the best

David

[office888]

Originally Posted by dpround

Thank you for the advice. I think my summary is that an ultrasonic bath might do the job, but it is not as cheap as I thought, which makes the new carbs possibly the better bet as they are a pretty sure fix. I think I'll have one last go manually cleaning them and then give up and spend the money.

All the best

David

It's a misadjusted float is what it sounds like.

All you need to do is pull the floatbowls off, remove the floats, and test them all to make sure they float properly. If they do, the tabs all need to be set to the proper height.

[uncle al]

before I retired, I used a sonic cleaner with a special soap, to clean carburetors , it made a bloody good job of it as well. The one I used was set at, 60 degrees centigrade and the timer was set for twenty minutes.Team tip don't leave them in the solution overnight as it lets the carbs grow whiskers, Blow through all the fuel channels as soon as you remove the carbs from the sonic cleaner.

[dpround]

Finally fixed it! Tried cleaning the carbs again. Guitar strings and carb cleaner spray seemed to be pretty good, but not convinced of any blockage. Tested the carbs on the electric fuel pump with the float chamber drain plug out. One filled, two did not. So I stripped and cleaned them again, and again. Finally I figured out that the previous owner had assembled two of the carbs with the floats upside down and so the float valve could not open when the carb was assembled!

If I were doing it again I would start with taking the carb drain plugs out and pumping the primer bulb to see if any fuel comes out! I think this would be a useful test with many multi-carb engines.

Anyway - thank you for all your help and advice!

David

[office888]

Originally Posted by dpround

Finally fixed it! Tried cleaning the carbs again. Guitar strings and carb cleaner spray seemed to be pretty good, but not convinced of any blockage. Tested the carbs on the electric fuel pump with the float chamber drain plug out. One filled, two did not. So I stripped and cleaned them again, and again. Finally I figured out that the previous owner had assembled two of the carbs with the floats upside down and so the float valve could not open when the carb was assembled!

If I were doing it again I would start with taking the carb drain plugs out and pumping the primer bulb to see if any fuel comes out! I think this would be a useful test with many multi-carb engines.

Anyway - thank you for all your help and advice!

David

Jamming stuff down the jets tends to enlarge/erode the soft brass orifices, which causes the outboard to run rich / unevenly.

[jeffstevens763@g]

Originally Posted by dpround

Finally fixed it! Tried cleaning the carbs again. Guitar strings and carb cleaner spray seemed to be pretty good, but not convinced of any blockage. Tested the carbs on the electric fuel pump with the float chamber drain plug out. One filled, two did not. So I stripped and cleaned them again, and again. Finally I figured out that the previous owner had assembled two of the carbs with the floats upside down and so the float valve could not open when the carb was assembled!

If I were doing it again I would start with taking the carb drain plugs out and pumping the primer bulb to see if any fuel comes out! I think this would be a useful test with many multi-carb engines.

Anyway - thank you for all your help and advice!

David

bugger when that happens glad you got sorted.
an old bloke i worked under allways told me process of elimination lad start at the bigining.

[dpround]

No risk of damage to jets in this case as I was just clearing/checking the fuel way in the carb body between the inlet and the float valve. Interestingly, the specific jet cleaners that I bought from ebay and didn't use were far more abrasive, like tiny files, rather than guitar strings, which were round wound with bronze wire...

[office888]

Originally Posted by dpround

No risk of damage to jets in this case as I was just clearing/checking the fuel way in the carb body between the inlet and the float valve. Interestingly, the specific jet cleaners that I bought from ebay and didn't use were far more abrasive, like tiny files, rather than guitar strings, which were round wound with bronze wire...

I prefer chemicals. I have owned far too many vehicles with permanently messed up stoichiometry due to eroded jets.

My solution is always the same:

1. Replace all rubber items
2. Replace jets
3. Adjust float
4. Install 10 micron fuel filter