Tohatsu 3.5 HP Carburetor

How to take out the carb of a Tohatsu 4 stroke outboard

I usually hand the carburetor cleaning over to an outboard mechanic, but it's way cheaper if you drop off the carb in the shop. Removing and later re-installing the carb can easily be done by the DIY cruiser. Here are the steps - the images show my Tohatsu 3.5 HP 4 stroke outboard:

The tools you need. Flat screwdriver, 10mm wrench with extension, needlenose plyers

First remove the hood and unscrew the three bolts securing the fuel tank.

After the bolts are gone, you can move the fuel tank to the side which makes it much easier to work on the carb.

Unscrew the carburetor drain screw; this will drain all fuel in the carb so you should position a paper towel below it.

Remove the top hose.

Unscrew the bolt holding the joke cable in place, then unhook the joke cable from the carb.

Pull the two lower hoses up and out.

Unscrew the 1st of the two bolts holding the carb in place.

Use the extension to carefully loosen the second bolt. Don't take the bolts out yet.

Grab the carb with one hand, remove the now loose bolts and take the carb off. Next you have to unhook the gas cable
by tilting the carb over 90 deg.

Find a tray for the carb. You can see the carb body in the middle, the air intake with the two bolts on the right side, and another
seal on the left side. The thing to remember is that the carb has 2 seals on the "left" side and no seal on the "right" side. This is it.

If you really want you can unscrew the two bolts and have a look inside.
And if this article helped you out, why not invite us for a beer.

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Comments  

+1 #5 Rob 2016-08-29 01:34

Hi Pete, re; the rubber bung, I had the same problem (i may also need to adjust my float level, because motor is reluctant to idle without part-choke, but i thought i'd replace the bung first). See link below. The website wont let me attach an 'insurance' screenshot, so I'll describe location as follows: With carby upside-down, float cover and float removed, bung goes in hole mid-way on side closest the inlet fuel hose nozzle.
Rob (Glasshopper).
https://www.google.com.au/search?q=tohatsu+3.5hp+carburettor+adjustment&client=firefox-b&tbm=isch&imgil=IpBxS3-dCNklnM%253A%253Bdhk0tLtzR2W_uM%253Bhttp%25253A%25252F%25252Fwww.greenpanther.org%25252Findex.php%25252Fdiy%25252F31-tohatsu-carb-removal&source=iu&pf=m&fir=IpBxS3-dCNklnM%253A%252Cdhk0tLtzR2W_uM%252C_&usg=__reEMxjnhlY0aszOpGoJVCPjkM2Y%3D&biw=1244&bih=608&ved=0ahUKEwinu6jcueXOAhXCl5QKHUqJBRkQyjcIbQ&ei=0ozDV6eKK8Kv0gTKkpbIAQ#imgrc=VFJ8t_rxJCD3NM%3A

+5 #4 pete 2015-10-19 12:56

Hi I took the bottom float chamber off and there was a small black rubber piece loose inside the carb chamber.
here is a link to show the parts, its item number 6 on the diagram. Any ideas where it goes inside the float chamber?
http://www.marineengine.com/parts/mercury-outboard-parts/25-4stroke-carb/0r131842-up/carburetor-serial-0r318096-and-up

0 #3 Stu 2015-05-08 05:05

I just got mine back from a OB mechaninc and he said I need a new one that some sludge is tuck in one of the jets and therefor the carboirator needs to be replaced Time for me to try now I don't believe he did it correctly I am not real happy with the shop. Nothing but problems since I got the new motor Thanks for the photo sprd

+1 #2 Chris 2015-03-13 23:07

Hi Diane, great that I could help! Sounds like you did an awesome job cleaning the carb. Happy sailing
-Chris

0 #1 Diane Lemieux 2015-01-12 22:11

Chris, I can't tell you how much this blog post helped us! It gave us the confidence to "go all the way". We have taken it to the fix it guy so often we were determined to learn how to do it ourselves. When we got to your last step we did take the carburetor apart and saw a puddle of yuk in the bottom. After cleaning it out with q-tips and wire, and reassembling, it started ON THE FIRST PULL!!!!
Thank you, thank you!
Happy Sailing!
Diane and Rock
Simple Pleasures
2saltydogs.blogspot.com

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