Bulb primer in diesel line

wipe_out · 18 Jun 2019

Just about to change out the Racor diesel filter on the boat for the first time and I have been looking at various videos in bleeding the fuel system after changing the filter using the small pump on the engine or spinning the engine with the decompression levers open..

Seems to me like one of those fuel priming bulbs in the main fuel line from the tank would make it all much easier.. Would also mean the air could be cleared right at the Racor filter assembly rather than pushing it all the way through the engine after a filter change..

Is there any reason this is a bad idea? Has anyone else done this?

PaulRainbow · 18 Jun 2019

wipe_out said:
Is there any reason this is a bad idea? Has anyone else done this?

Good idea. Don't you also have a 2nd filter ?

BabaYaga · 18 Jun 2019

wipe_out said:
Is there any reason this is a bad idea? Has anyone else done this?

Can't see why it would be. I have used one since repowering in 2006 and found it very convenient.
Same goes for the drip tray under the filter.

wipe_out · 18 Jun 2019

PaulRainbow said:
Good idea. Don't you also have a 2nd filter ?

Yes and figure I could probably use the same bulb to clear the air out of that too.. Or fall back to the engine pump..

wipe_out · 18 Jun 2019

BabaYaga said:
Can't see why it would be. I have used one since repowering in 2006 and found it very convenient.

Yes, that's exactly the idea.. Will try and get one tomorrow..

PaulRainbow · 18 Jun 2019

wipe_out said:
Yes and figure I could probably use the same bulb to clear the air out of that too.. Or fall back to the engine pump..

Fit the bulb before the Racor and it will push the fuel through both filters, no need to use the engine lift pump.

You'll wonder why you didn't fit one a long time ago

RichardS · 18 Jun 2019

I have bulbs like that on both my 3YM30s although I've never had to use them as both engines seem to self-prime after changing primary or secondary filters or even after completely removing the filter units and taking them home for refurbishment.

I don't know what it is that makes my engines self-prime whilst others obviously do not, but it does make me wonder why the bulbs were ever fitted by the boat manufacturer.

Richard

Sandy · 18 Jun 2019

I use gravity, a bit of brilliant French engineering.

oldharry · 18 Jun 2019

Sandy said:
I use gravity, a bit of brilliant French engineering.

Not always possible though without inverting the boat! I hope its ok to use a bulb primer - mines worked fine since I fitted it some years ago. Makes priming and bleeding so easy! Some cars, including Peugeots (I know, not much of a recommendation!) have them too.

William_H · 19 Jun 2019

Just wondering if bulbs are not provided from the beginning because some regimes consider the rubber not sufficiently fire proof. That and possible rubber deterioration seem to be the only down side to fitting a bulb. Of course they are almost universal in outboard engined boats with remote fuel tank. Perhaps fire is not considered so much there being open and outside. ol'will

Tam Lin · 19 Jun 2019

One was fitted to my boat when the new engine was installed. A good idea.

Bobc · 19 Jun 2019

I fitted on when I re-powered recently. I fitted it between the tank and the primary filter, and it makes bleeding the system so much quicker and easier.

ghostlymoron · 19 Jun 2019

Why not install one of these? https://www.asap-supplies.com/fuel-...s/cav-type-oem-fuel-filter-with-primer-302052
Much cheaper than Racor, built in pump, cheap replacement elements too. Personally I think the outboard motor bulb type are a bit of a bodge and I would be concerned about fire resistance.

PCUK · 19 Jun 2019

Standard fit on many cars and trucks, so no problems to be encountered.

ghostlymoron · 19 Jun 2019

So, what's not to like much better than rubber hose and jubilee clip.

PCUK said:
Standard fit on many cars and trucks, so no problems to be encountered.

Plum · 19 Jun 2019

ghostlymoron said:
Why not install one of these? https://www.asap-supplies.com/fuel-...s/cav-type-oem-fuel-filter-with-primer-302052
Much cheaper than Racor, built in pump, cheap replacement elements too. Personally I think the outboard motor bulb type are a bit of a bodge and I would be concerned about fire resistance.

+1 although my Vetus (Mitsubishi) engine is self bleeding. After a filter change give 10 pumps on the lever on the engine mounted fuel pump then crank for max of 10 seconds, usually less then 5, and it starts. No need to open any bleed screws.

Www.solocoastalsailing.co.uk

Sandy · 19 Jun 2019

oldharry said:
Not always possible though without inverting the boat! I hope its ok to use a bulb primer - mines worked fine since I fitted it some years ago. Makes priming and bleeding so easy! Some cars, including Peugeots (I know, not much of a recommendation!) have them too.

That made me laugh, but I get your point. While I don't have any plans to buy another boat I always look for a fuel tank higher than the engine.

Stemar · 19 Jun 2019

CAV filters are such a pain to change, especially when it's dark and bumpy, which is when a filter's most likely to get blocked. I got rid of mine after a rather fraught entry in Portsmouth Harbour under sail, and fitted a pair of spin-on car filters obtained from a scrap yard. Taps top and bottom, and I can switch filters in seconds. I could probably change and prime one filter while the engine's running on the other, but I've never tried.

Over the years, it's saved me money because I no longer changed filters on an annual, precautionary basis. After a dozen years or so, I changed them for the first time last year because they were getting rusty enough to be a concern. I expect the current set to come close to seeing me out.

I don't need a bulb because the tank's above the filters, but it wouldn't bother me to have one. Yes, there's a theoretical risk in the event of fire, but I think you'll find that most boats have at least one bit of rubber hose to allow the engine to vibrate, so no real difference.

Heckler · 20 Jun 2019

wipe_out said:
Just about to change out the Racor diesel filter on the boat for the first time and I have been looking at various videos in bleeding the fuel system after changing the filter using the small pump on the engine or spinning the engine with the decompression levers open..

Seems to me like one of those fuel priming bulbs in the main fuel line from the tank would make it all much easier.. Would also mean the air could be cleared right at the Racor filter assembly rather than pushing it all the way through the engine after a filter change..

Is there any reason this is a bad idea? Has anyone else done this?

Squeezy bulb, yes, makes it so easy to bleed

srah1953 · 21 Jun 2019

ghostlymoron said:
Why not install one of these? https://www.asap-supplies.com/fuel-...s/cav-type-oem-fuel-filter-with-primer-302052

If I installed this as secondary filter on engine, would it bleed through after changing primary filter?

Bulb primer in diesel line

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