Yamaha 4 Stroke Outboard Engine Carb Rebuild Series - Fuel Pump Rebuild and Test

Having been working on the project to rebuild the carbs of the engine. Debris has been found in the bowls of all four carbs. It seems like a good idea to do a carb rebuild before reinstalling the cabs back onto the engine.
Two of the three connections are already removed from the pump from the carb removal so only the input coming from the fuel filter need be removed. Two bolts secure the pump onto the engine which are removed, releasing the pump which is brought over to the bench.
Before disassembly, a test of the pump is conducted, given the tools that I have on hand to ensure that the internals are still functioning properly. My method is not standard but the results do demonstrate that the diaphragm , which is expensive is still working good. I did see black slime coming out of the pump during the tests though so a cleaning is in order.
Disassembly begins, the pump secured with four screws separating the two halves, the gasket and a seal are shown to be long since destroyed, the bottom portion is then disassembled, removing the plunger and spring followed by the valves. Now fully disassembled all parts are cleaned with carb cleaner and blown out with air except for the diagram which is carefully cleaned with a clean paper towel.
With all parts cleaned assembly was conducted stating with the lower plunger portion. Then the top portion starting with the valves, Gaskets are replaced on the top of the pump as it is assembled.
62Y-24452-00 -gasket
62Y-24471-00 membrane
The bolts holding the fuel pump together call for loctite 572. I use Loctite 592 as it is more readily available
Loctite 59214
Both side are brought together and tightened down progressively in a cross pattern. This is followed by basic testing again to ensure that everything inside was assembled properly. Back at the boat the pump is primed and tested manually before re-installation onto the motor. Finally reconnecting the hose from the fuel filter to the in port.
#yamahaoutboards #yamahaoutboards

[@KLyonFL]

Nice job…
Changing the LP pump on my 02 DF140 tomorrow.

[@delorean1]

Good luck.

[@chrisseegert9345]

Your videos are awesome and very much appreciated. I found that Vaseline works good with gaskets to

[@delorean1]

Glad they helped.

[@hungnguyen-bv6mk]

THANK YOU . VERY MUCH FOR YOUR VIDEO

[@delorean1]

You are welcome!

[@regkershaw]

It's good you could get a service kit for this pump...
I have a yamaha f70 4 stroke injection outboard and I had an issue with the same pump I was told it was the low pressure pump and its a issue with yamaha that these pumps fail and leak fuel into the oil in the engine and cause damage...
I was informed by a dealer that a kit wasn't available and I had to buy a new pump which cost $350 Australian dollars.
I was pissed that a kit wasn't available and for this to be an issue with the outboard to have to pay that amount....

[@GasGuzzlerV8]

Hi! Thank you for video! I think this is exactly problem im my engine, who start after one day or more, at 4th 5th time! He waste fuel in fuel line! Thanks again1

[@st.k.4528]

May I ask about your setup, it seams unclear to me. Do you apply pressure to inlet or outlet? I have a smaller pump, when I connect my gauge to outlet and pump the plunger manually, pressure rises and drops doesn't matter if I plug or leave free the inlet port.

[@saddamsobig2348]

I have Yamaha F 40 A same issue

[@jakeclark3751]

Mine only come out of the top out line not the one under it

[@saddamsobig2348]

From where you get spare

[@cro2eventstuttgart607]

Hello has the same problem I can’t go over 4500 RPM and high speed is maximum 30 km/h and I have opened a fuel pump and I have to see a broken. Is that the reason? 17:01

[@danieltravis2850]

So are we thinking the crud in there is from sour gas or are the fuel lines breaking down?

[@delorean1]

That’s the thought. From the old fuel tank since replaced.