Engine Stopped - Query

[BlowingOldBoots]

My engine stopped the other day when at sea. It’s a Perkins 4236 and has been 100% reliable, until this even,t in my 16 years of ownership. It sounded like fuel starvation or air in the system. After bleeding the engine it started and ran for 5 minutes. Drifted into the anchorage and changed filter et cetera and it again ran for about 5 minutes.

I noticed the following the: the vacuum gauge on the fuel filters is stuck in the high vacuum position. Even after changing the filter and bleeding the system, the vacuum gauge remains high. This is strange. I also noticed that the fuel hose between the filter outlet and the lift pump has a couple of flat spots around the centre. The flat spots look like copper pipe that has been compressed. The hose is a fire rated fuel hose with hard tails, hose, stainless cover, heat resistant cover, so it is not a copper pipe.

I can’t get the engine started now and each time I bleed it, there is foamy fuel coming out before it cleans up and runs for about a minute. The tank is 4/5ths full, so plenty of head to push fuel through.

Do you think that a lift pump could collapse the suction hose between the filter and lift pump if the inlet to the hose was blocked?
I wonder how vacuum pressure could be trapped?

Any ideas?

I’ll be lifting the boat soon and will strip the fuel system anyway to check.

Fuel Hose on vacuum side: https://www.asap-supplies.com/products/ ... th-1-57933
Fuel Filter Unit: https://webshop.vetus.com/en/product/ve ... max-360l-h

[Gardenshed]

hose degraded? bits of rubber blocking the hose?
remove the hoses and blow through with compressed air (I've got a wee compressor if you want to used it)...or replace them.
start from the engine and work back to the tank to see where the block is

[BlowingOldBoots]

Thanks for the advice. I am wondering if it is something like a hose stripping, or chunking internally bits of rubber. I'll inspect first and if I need the compressor I'll contact you and take you up on the kind offer.

[Burst Boiler]

Tank breather blocked? Try running with the filler cap removed.

[BlowingOldBoots]

Thanks, I’ll add that to my checks.