Bubbles in first stage deisel filter

[poultey]

I've recently acquired a Moody 31 mk II with Volvo Penta 2003 28hp. The first stage fuel filter pictured with orange inspection bulb has a steady stream of fast moving bubbles that seem to eminate from the bottom drain screw when the engine is running. My question - is this normal ? The engine runs for 10 minutes in idle or in gear then splutters to halt. Pre-purchase the boat was sat on the hard, I'm told with no fuel in the tank for 2 years. Any thoughts appreciated.

Just a more general thank you to the forum from whom I've received invaluable contributions to recent posts.

 

[lusitano]

I've recently acquired a Moody 31 mk II with Volvo Penta 2003 28hp. The first stage fuel filter pictured with orange inspection bulb has a steady stream of fast moving bubbles that seem to eminate from the bottom drain screw when the engine is running. My question - is this normal ? The engine runs for 10 minutes in idle or in gear then splutters to halt. Pre-purchase the boat was sat on the hard, I'm told with no fuel in the tank for 2 years. Any thoughts appreciated.

Just a more general thank you to the forum from whom I've received invaluable contributions to recent posts.

Bubbles = Air = not good. If you carefully remove the bowl drain plug ( extra carefully, they are inclined to shear off)
Clean up and refit with a new rubber ring washer.

 

[alahol2]

Not convinced that's a filter, looks more like a water separater only.
Agree with Lusitano.

 

[vyv_cox]

Under normal conditions there is insufficient suction to draw air past the seal. The only time I have seen significant amounts of air drawn into the bowl was when the filter media was partially blocked by diesel bug. Some up-market filters have vacuum gauges for just this reason. I suggest you inspect the filter and maybe the tank.

 

[poultey]

Not convinced that's a filter, looks more like a water separater only.
Agree with Lusitano.

@alahol2 you're absolutely right it is a water seperator - my error mis identifying. On closer inspection the rubber washer is hard and perished and replacement looks to be maintaining a tight seal. Than you for the response - great forum.

 

[Refueler]

Its a First Point to look at with anything like this :

Seals. Even if they look good - REPLACE and do NOT overtighten ....

Overtightening is probably the most common cause of seals failing.

 

[poultey]

Its a First Point to look at with anything like this :

Seals. Even if they look good - REPLACE and do NOT overtighten ....

Overtightening is probably the most common cause of seals failing.

Good advice Refueler. If anyone's able to identify the manufacturer of the orange inspection/water seperator would be appreciated for replacement seal purposes otherwise I'll go with a non-oem.

 

[Refueler]

Good advice Refueler. If anyone's able to identify the manufacturer of the orange inspection/water seperator would be appreciated for replacement seal purposes otherwise I'll go with a non-oem.

A good Motor Factors should be able to match the seal ...

 

[MontyMariner]

Buy Nitride O rings, you can get them from any motor facrors

 

[lusitano]

There could also be a problem with the fuel tank breather - blocked and creating a vaccum.
Easily checked by running engine with filler cap removed

 

[Bodach na mara]

I had a separator like that on another boat dating from the 1960s. It had a gauze coarse filter round the spigot in the alloy upper part. This filter was the cause of several engine stoppages due to sludge from the tank clogging it.

It was easily removed for cleaning but the ultimate cure was to drain, clean and rinse the tank. This was at the time when red diesel was less than £1 per gallon by the way!

 

[Refueler]

Guys .... >>>

Quote : On closer inspection the rubber washer is hard and perished and replacement looks to be maintaining a tight seal. Thank you for the response - great forum.

<<<<<<<<<<<

Job done.

 

[penberth3]

Buy Nitride O rings, you can get them from any motor facrors

Nitrile with an L. Nitride is something completely different.

 

[Refueler]

Nitrile with an L. Nitride is something completely different.

Walk into Motor factors ...

Hi - I have this diesel water separator - can you help me with new seals for it ?

Sure .. guy takes item and measures it ... scuttles off to the stock .. returns with seal in hand ... you part with a quid or few quid - whatever ...

Bobs proverbial .... Nitrile ? Never heard the word !! Guy just supplies whats needed.

 

[OCuea]

You can buy kits ….. Amazon perhaps …… to make nitrile o rings. Kit has different diameters of nitrile and the special glue. Obviously you need a big of skill to measure well and cut and join well. Might be a good kit to keep on board.

 

[MontyMariner]

Nitrile with an L. Nitride is something completely different.

Oops!

 

[Mister E]

Modern motor factors would probably need a computer ready part number and registration number to find one.