Fixed my Yanmar 3gm30 with Harley Davidson parts

[bamabaxter]

Just thought I would share. I sent injectors to be refurbed. When I got them back, installed them and reattached all lines. Added new crush washers(did not want anneal the old ones) to the fuel return lines which are banjo fittings.....which I hate. Managed to break a bolt (yes I know they don't need to be that tight) and decided to try something I read about on another forum. Yanmar does not use copper crush washers on the fuel returns on the later model engines and instead uses a rubber o-ring/metal washer combo. I did not have the patience to order them from a Yanmar distributer, so I decided to go a different route. Harley Davidson uses the same style washer/o-ring on their brake calipers. If they can handle Dot3/4 brake fluid at the elevated temperatures and pressures, then they should be able to handle diesel at very low, if any pressure. On they went with new banjo bolts and tightened. Zero leaks. Highly recommend these.

 

[Ralph Johnstone]

Added new crush washers(did not want anneal the old ones) to the fuel return lines which are banjo fittings.....which I hate.

Perfect solution.

I recently renewed several copper crush washers on banjo joints when I installed an electric fuel pump last year. Already one has started with a microscopic leak. Was never able to get those to hold for more than a few years before the micro leak started. Nothing serious, just a bloody mess all over the engine. And this is only at a few PSI with cold fuel supply.

I'll try one in a conspicuous place with paper towel wrapped just below the banjo fitting as a tell tale.

If they can handle Dot3/4 brake fluid at the elevated temperatures and pressures, then they should be able to handle diesel at very low, if any pressure.

Hell, I'm so OCD I'll probably soak one in diesel fuel over the winter to make sure the rubber holds up. I'm sure this is an "impossible" fire hazard regulation requiring that all gaskets on fuel lines to the engine be metallic. However, when I see plastic bowls on fuel filters, maybe not so much.

 

[bamabaxter]

Hey I understand OCD. Trust me. If there is a catastrophic event bad enought to destroy the oring inside the metal washer, then your fuel lines are already toast.

 

[Ralph Johnstone]

Hey I understand OCD.

I wanted to be sure that if the boat was ever to burn to the waterline, these washers would be the only thing left intact.

Now THAT'S OCD .

 

[FastOlson]

Those nifty washers are called 'bonded washers'. I located them when looking for a better way to keep the ATF oil inside our transmission... the drain plug needed a better seal than the aluminum washer that it came with. I also have one on the banjo fitting for the engine pan where the oil drain suction hose is attached.

 

[jviss]

the aluminum washer that it came with

Those aluminum washers are crush washers, too, good for one use. I have a bag of them on board, they're very cheap, and useful on the BMW motorcycle, Honda car, etc.

I like these re-useable ones, but I'm already all set with lifetime supplies of various sizes of aluminum and copper crush washers!