It’s the diaphragm type bolted to the motor beside the dipstick.
The engine operates it.
I would have just replaced the rubber if it weren’t for the impatient people around here.
A good bit cheaper
Got it from the fuel pump factory
Thanks @sman. Thats the low pressure pump. The high pressure pump is just behind the top of the three intake chambers. I made somewhat of some progress today on diagnosing my issue.
I am now able to recreate the issue in my driveway. I covered the motor with a thick drop cloth in the hot sun and got the engine temp to 116F while idling at 2500 RPMs. Once it got to 117F I immediately shut the engine down and let it sit for 10 minutes.
It would not start. Here are some things I noticed:
- The high pressure pump was not running when the ignition switch was turned to ON…it should.
- There was no pressure in the fuel line when I pressed the schrader valve.
- The was no voltage on the leads powering the high pressure pump.
- There was no long beep coming from the motor when the ignition was turn ON and the three LEDs on the tiller handle were not coming on.
This leads me to believe that I have a problem with computer modeule?..not sure what it is called.
I am posting this detail hoping someone can confirm or recommend more diagnostic testing.
read on down about the vst pump and filter. Its worth a try.
OR, be nice and ask here on the Tohatsu owners page.
with that current diagnosis my guess is the ecu. sorry, but ebay is your friend.
Thanks EF! I did more testing and found that the ECU is not getting power when motor is hot…I pulled the fuse on the circuit that powers the ECU and it behaves that same when it gets hot. I also hear a relay clicking…just need to find it and test it.
Im still trying to track down my problem. Its really weird. Motor cranks and runs fine initially. Once it sets for few minutes it will not crank. And when it does it runs terrible. I have setup an appointment at Muddy Bay in Newberry, SC to spend all day troubleshooting…I will report what we find here in this thread.
After reading about your troubles and seeing so many Tohatsu engines sitting at shops, I doubt if I will ever own one.
Of course I said similar stuff like that about Toyota a few decades ago, so maybe not, but probably, lol
Yeah…its definitely concerning. The tech is now very interested in what is wrong…curious more than anything. But I am not sure Ill keep the motor once it is fixed.
Spent time with tech at Muddy Bay today to diagnose the issue with my Tohatsu. Spent 3 hours troubleshooting. He got to see the weirdness of the symptoms first hand. The master relay switch would engage then all of a sudden it would stop working (which meant nothing else was getting power). Wiggled wires around. Unplugged connections. Ohm tested leads. Nothing was consistent. The electrical system would work then stop working. Over and over.
We swapped out the tiller steer with another one to eliminate the ignition switch….same results.
We swapped out the ECU…… bam! Everything worked consistently. Even after testing with the hose hooked up.
Took it to Murray. Ran down lake for 20 minutes. Stopped and let it sit for 10 minutes. Started fine ran great!
Things are looking good. Just gotta order an ECU (ouch) but at least it’s fixed.
Oh yeah. Muddy Bay didn’t charge for the techs time! Awesome team at Muddy Bay!
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