Volvo Penta CAV filter thread size

stav said:
A cheap vernier caliper and thread pitch tool would be useful? Happy hunting


Thread pitch tool
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The trouble is, without knowing which type the thread is I’d need multiple of those and only use them once. That’s ok in a house but on a boat it’s hard to justify. I can buy one of each size barb for less than the thread tools would cost.

Yes I do have calipers on board and will use them to measure
 
Yes xyachtdave,you are absolutely right. The Racor is big.


I had the same problem.and fitted a screw on type filter housing with water separator. R12T type. A almost like for like replacement.
 

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penberth3 said:
And how does that answer the original question?
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Solves the issue of replacing a bolt of unknown thread in an antiquated filter system, plus makes filter changes much simpler in future if update completed.

Not an expensive upgrade with copy parts available of good quality for not a lot.of.money.

It's nice to know there are other options out there. Ever tried changing a CAV Filter in lumpy conditions at sea? Not an experience I'd like to repeat.
 
Again though, I’m not replacing a bolt I’m finding a hose barb to use the bleed screw hole to extract diesel and also suck out the air when changing filters.
I have changed both primary and secondary filters in lumpy seas returning from Ireland, neither were a real problem, possibly thanks to using a pump on the bleed port.
 
lustyd said:
Again though, I’m not replacing a bolt I’m finding a hose barb to use the bleed screw hole to extract diesel and also suck out the air when changing filters.
I have changed both primary and secondary filters in lumpy seas returning from Ireland, neither were a real problem, possibly thanks to using a pump on the bleed port.
Click to expand...
I've not been able to find the source since but on my VP 41's I got a pair of quick seal bleed nipples in stainless, I seem to recall there were various thread options, it replaced the bleed screw and the top section has a ball and spring inside so no air can get back in, I just slacken off, attach pela oil suction pump and as soon as clear diesel appears in the pipe pull it off the nipple, the remaining suction pulls the diesel straight into the oil sucker with no mess and the nipple can be nipped up in your own time.
Never failed me yet and with the extra pull from the pela pump it can do the full system right back to the tank and pre-filter in one go, no messing with fuel pump lever.
A full mess free bleed in about a minute.
Now have facor pre-filters in a location that can be accessed easily from saloon so they are not an issue any more.

This sort of thing but mine were singles from fleabay at the time. Nipples
Edit:
Just had a quick search and there are some one piece versions with the ball valve inside, you don't want those ones as pump pressure will open the valve and spurt diesel out, I had to cut the end off the thread on mine to fit properly.
 
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Thanks I wasn’t aware those existed and they seem like a great solution. Still need to work out the thread but might then order one instead of a hose barb.
 
snowbird30ds said:
I've not been able to find the source since but on my VP 41's I got a pair of quick seal bleed nipples in stainless, I seem to recall there were various thread options, it replaced the bleed screw and the top section has a ball and spring inside so no air can get back in, I just slacken off, attach pela oil suction pump and as soon as clear diesel appears in the pipe pull it off the nipple, the remaining suction pulls the diesel straight into the oil sucker with no mess and the nipple can be nipped up in your own time.
Never failed me yet and with the extra pull from the pela pump it can do the full system right back to the tank and pre-filter in one go, no messing with fuel pump lever.
A full mess free bleed in about a minute.
Now have facor pre-filters in a location that can be accessed easily from saloon so they are not an issue any more.

This sort of thing but mine were singles from fleabay at the time. Nipples
Edit:
Just had a quick search and there are some one piece versions with the ball valve inside, you don't want those ones as pump pressure will open the valve and spurt diesel out, I had to cut the end off the thread on mine to fit properly.
Click to expand...
My VP41 self-bleeds after a primary (Racor) or secondary filter change. Just turn the key, it either starts or crank for 3 seconds then it starts. Even on one occation after refitting the fuel pipes between pump and injectors, it started after a few seconds of cranking without doing any bleeding.

Also, my Vetus (mitsubishi) diesel will self-bleed after a CAV filter change.
 
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snowbird30ds said:
I've not been able to find the source since but on my VP 41's I got a pair of quick seal bleed nipples in stainless, I seem to recall there were various thread options, it replaced the bleed screw and the top section has a ball and spring inside so no air can get back in, I just slacken off, attach pela oil suction pump and as soon as clear diesel appears in the pipe pull it off the nipple, the remaining suction pulls the diesel straight into the oil sucker with no mess and the nipple can be nipped up in your own time.
Never failed me yet and with the extra pull from the pela pump it can do the full system right back to the tank and pre-filter in one go, no messing with fuel pump lever.
A full mess free bleed in about a minute.
Now have facor pre-filters in a location that can be accessed easily from saloon so they are not an issue any more.

This sort of thing but mine were singles from fleabay at the time. Nipples
Edit:
Just had a quick search and there are some one piece versions with the ball valve inside, you don't want those ones as pump pressure will open the valve and spurt diesel out, I had to cut the end off the thread on mine to fit properly.
Click to expand...
Wow, over a 100 quid for 4.

These are a pack of different sizes. Maybe one will fit? A lot cheaper. Perhaps I've missed something in the spec though?

Amazon.co.uk
 
lustyd said:
Again though, I’m not replacing a bolt I’m finding a hose barb to use the bleed screw hole to extract diesel and also suck out the air when changing filters.
I have changed both primary and secondary filters in lumpy seas returning from Ireland, neither were a real problem, possibly thanks to using a pump on the bleed port.
Click to expand...
What's to stop air getting back in through whatever hose you're using to suck air out ?

I don't understand what you're trying to do or what the current problem is with bleeding.

If you want to stick with the CAV filters fit one of these: CAV Lucas Delphi filter head with primer pump 9001-742G - Diesel Injection Pumps

A few pumps with that and hit the key, it should start within in seconds, no need for bleeding.
 
snowbird30ds said:
I've not been able to find the source since but on my VP 41's I got a pair of quick seal bleed nipples in stainless, I seem to recall there were various thread options, it replaced the bleed screw and the top section has a ball and spring inside so no air can get back in, I just slacken off, attach pela oil suction pump and as soon as clear diesel appears in the pipe pull it off the nipple, the remaining suction pulls the diesel straight into the oil sucker with no mess and the nipple can be nipped up in your own time.
Never failed me yet and with the extra pull from the pela pump it can do the full system right back to the tank and pre-filter in one go, no messing with fuel pump lever.
A full mess free bleed in about a minute.
Now have facor pre-filters in a location that can be accessed easily from saloon so they are not an issue any more.

This sort of thing but mine were singles from fleabay at the time. Nipples
Edit:
Just had a quick search and there are some one piece versions with the ball valve inside, you don't want those ones as pump pressure will open the valve and spurt diesel out, I had to cut the end off the thread on mine to fit properly.
Click to expand...
The ones you link to are for bleeding the brakes on a car, where lifting the pedal can suck air back into the system, for that job, one of these will do the same job for £2.75

For bleeding the diesel system there is no need for such a thing, nothing should be sucking air back in. Using a Pela pump as you describe, the vale adds nothing of value, you could just as easily use one of these:

SSBN8-4Z5__25341.1750415810.386.513.jpg
 
PaulRainbow said:
I don't understand what you're trying to do or what the current problem is with bleeding
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No problem at all. A well fitting hose will just be easier than pushing a plastic hose in.

I’m also using it to pull diesel from the tank to empty the tank. It saves removing other fittings and potentially introducing leaks. Most of the time the existing bolt will be in place.
 
xyachtdave said:
I swapped my Volvo pre filter out for one of these. The access for the original glass bowl set up was terrible and changing filters a messy process.

Anyway that’s not why you rang…it claims to be like for like replacement but wasn’t. UNF fittings on new unit, unfortunately not compatible with my existing fittings and pipework. Like for like…!

I’d guess there’s no right answer to this question.

Spin On Fuel Filter Conversion Kit (CAV Replacement)
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Does look like you lose the water separator function with that. Probably a good idea to fit a water operator in l8ne somewhere.

Or replace with a more modern type as already discussed.
 
PabloPicasso said:
Does look like you lose the water separator function with that. Probably a good idea to fit a water operator in l8ne somewhere.

Or replace with a more modern type as already discussed.
Click to expand...

In 20 years I’d never drained water out the separator so wasn’t worried about that feature.

The spin on filters are changed in seconds rather than 20 mins of faffing about with the various o rings and glass bowl.

The other advantage is you can pre fill them or add injector cleaner etc straight to the filter itself, Forte do some excellent products that work better in the filter rather than added to the tank.
 
Takes me a couple of minutes even at sea. The trick is holding the stack from the bottom and threading the bolt down into it.
 
xyachtdave said:
In 20 years I’d never drained water out the separator so wasn’t worried about that feature.

The spin on filters are changed in seconds rather than 20 mins of faffing about with the various o rings and glass bowl.

The other advantage is you can pre fill them or add injector cleaner etc straight to the filter itself, Forte do some excellent products that work better in the filter rather than added to the tank.
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Good fot you. You've been lucky. It only takes one time.
How bad would water be to a running engine?

Fitting a water sperator would be a sensible upgrade, and could save you huge engine repair expense.
 
lustyd said:
Takes me a couple of minutes even at sea. The trick is holding the stack from the bottom and threading the bolt down into it.
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Well good for you. You're clearly more skilled at changing them than me. I had a mal de mer inducing hell trying to change one in awful conditions before entering the harbour returning from a long trip. Big seas, breaking waves into the cockpit and spraying into the cabin, boat heaving in all directions in confused seas. I guess it stirred enough crud up from the tank bottom to block the filter.

No one else could tolerate it below, and it took multiple attempts, access was awkward, and I couldn't get the stack of parts to seal properly. Managed "eventually" to the relief of all aboard.

A drop in or screw on type would have made it a lot easier. I now feel it's a critical safety issue.
 
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