Fuel filter problems

[Olaf Biofuels Forum Newbie Find all posts View Profile Close Olaf]

Hi There,
This might be of interest to budding WVO's.
During the course of converting a Mazda 2.5 Turbo (indirect injection, Zexel rotary IP) I had trouble getting the 12volt fuel pump (Holley Blue - vane type) to work consistently.
To give it a helping hand I decided to place the WVO return line before the pump (and WVO filter). The assumption being that the return lines hot WVO would make the pump perform better and allow the WVO to pass through the filter easier, thereby further aiding the pump.
Big mistake:
My fuel filter is a standard 'glass bowl' unit available from any diesel/hydraulic shop. The filter cartridge sits between the upper housing and the glass bowl and contains what looks like pleated paper or cardboard. The same model has had over 1000 litres of cold WVO (pre-filtered to 1 micron) gone through it without a cartridge change in my Toyota BJ42.
However, in the Mazda after only a few hundred kilometers with the return line in front of the pump/filter, the paper in the cartridge started to disintegrate and bits of fluffy paper mache blocked the metal mesh filter in the IP, thus stalling the engine.
According to the filter supplier these diesel filter cartridges are NOT suitable for HOT liquids, diesel or otherwise! They suggested to use engine oil filters instead, which are obviously designed to take hot oil.
If any of your guys/girls are running hot oil through their filters, please post a reply here - I'b be interested to know how you fared/what filter you use, etc.
Best regards,
Olaf

[Guest Close David]

Re: Fuel filter problems

Hi Olaf,

I am not sure what micron filtration you are looking for from the WVO filter but I think you should look into the micron rating of engine oil filters. I have read many articles where they have been described as more like "strainers" rather than filters. If you are wanting to get say 5 or 1 Um filtration, You may want to make sure the engine oil filters are actually rated that fine. I have suspicions they are not anything like that so you may want to verify this one way or the other. Perhaps different brands have different ratings so it would pay to know which filters have the finest rating.

You may also want to look into the bypass feature which I believe most filters have these days. I believe once the filters reach a certain pressure/ resistance, an internal valve opens which by passes the filter so the engine still recieves full, if dirty oil flow to prevent damage through loss of oil pressure.
I would think if a load of dirty fuel were to block the filter in a fuel application it would be highly prefrable for the engine to stop than have the filter go to bypass and have the engine digest a whole load of nasstiness which could do major damage.

Certainly I am no expert but if the micron rating is high as I suspect and the filters are " full flow", I think they would be highly unsuitable as fuel filters. If I am correct there still maybe different types for trucks or industrial applications that would be suitable for what you want. That being the case I would then be checking out the price and availability of these filters before making any modifications to use them.

Best you check out what the situation with the engine oil filters actually is and if there are any types to avoid or what you need to use.

[Olaf Biofuels Forum Newbie Find all posts View Profile Close Olaf]

Re: Fuel filter problems

Hi David,
Thanks for your reply.
The oilfilter cartridge is labled 5 micron, but the possibility of an internal bypass I had not considered.
I will closely examine the unit - it was given to me by a diesel mechanic who made no mention of it. Scary...
Best regards,
Olaf

[isuzurover Junior Member Find all posts View Profile Close isuzurover]

Re: Fuel filter problems

I work in filtration research, so may be able to offer some help...

The "micron" rating is a bit of a misnomer, since filters very rarely work as a sieve (only for really large particles) - most filters remove particles by interception, inertial collection, or diffusion. Therefore the filter has an efficiency curve like that shown below.

You have to make sure that all manufacturers are using the same rating method, as this isn't always the case - e.g. some may be giving you the size where the filter achieves 100% efficiency, but more likely you will get the 98% efficiency size, 95%, or even 50%!

To add to the information on the media, most filter media is cellulose fibres, glass fibres, or a combination of both. Usually the filter is held together by a binder. I suspect that in your filter, the binder was not stable at high temperatures.

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Fuel filter problems

Hi There,
SNJP
My fuel filter is a standard 'glass bowl' unit available from any diesel/hydraulic shop. The filter cartridge sits between the upper housing and the glass bowl and contains what looks like pleated paper or cardboard. The same model has had over 1000 litres of cold WVO (pre-filtered to 1 micron) gone through it without a cartridge change in my Toyota BJ42.
However, in the Mazda after only a few hundred kilometers with the return line in front of the pump/filter, the paper in the cartridge started to disintegrate and bits of fluffy paper mache blocked the metal mesh filter in the IP, thus stalling the engine.
According to the filter supplier these diesel filter cartridges are NOT suitable for HOT liquids, diesel or otherwise! They suggested to use engine oil filters instead, which are obviously designed to take hot oil.
If any of your guys/girls are running hot oil through their filters, please post a reply here - I'b be interested to know how you fared/what filter you use, etc.
Best regards,
Olaf

Olaf,
Are you able to advise the brand and model of this filter cartridge please?

[Tim-HJ61 Donating Member Find all posts View Profile Close Tim-HJ61]

Re: Fuel filter problems

I have been concerned by Olaf's experience and today received a response from Ryco filters that makes be a lot more relaxed. The question I posed related to vege oil heated to approx 70°C and run through a RycoR2132P filter suitable for the CAV/Delphi 296 filter body with the glass bowl underneath.

**********
Whilst it would be unwise to subject nylon body petrol filters to high temperatures, the CAV type R2132P filter is made using the same type of materials that would be used in oil filters. That is, the same adhesive, and similar media as is used in a bypass oil filter, and a steel body & endcaps. Typically oil filters are tested in our laboratory at 80 degrees (for the standard tests) and on occasion we have tested at 130 degrees. Therefore, I do not see a problem with using the R2132P filter element at 70 degrees.
**************

I have posed a similar question to Delphi, but have not as yet had a reply.

Tim

[Cameron Moderator Find all posts View Profile Close Cameron]

Re: Fuel filter problems

Great research there Tim - nice one!

I was getting a bit worried as I read through the thread there but you went hunting and solved my exact question!

Thanks Isuzu Rover for the filter info too - very informative.

Cheers,
Cameron

[tbird650 Senior Member Find all posts View Profile Close tbird650]

Re: Fuel filter problems

I had a similar experience with fuel filter disintergration on my Hiace 2.4 . I am heating prior to the standard Hiace filter. After maybe a year the filter was found to have holed. The van is now very slow and smokey. The injectors, I checked and are clear. The pump is a bit more daunting but after the previous post re gauze in pump, blocked..... I guess I have to venture in.

What are others doing for filters?......and heating before or after? What change intervals?

Even if the injector pump is absolute toast,,,,I have saved mored in fuel costs than the van is worth to replace. Still, I'd like to save it if possible.
So in this regard, does anyone have knowledge of Toyota pump internals, gauzes, degree of difficulty and any special tools etc......or even access to a manual.

Comments invited, cheers.

[Captain Echidna Senior Member Find all posts View Profile Close Captain Echidna]

Re: Fuel filter problems

Sorry I cant help, but on my merc I have 2 glass fuel filters, (Available from whitworth marine and leisure if your auto parts doesnt have them), Easily see the colour of what is going in and out (if what is coming out is darker than what is going in, there is still veg oil in there), I hope if faced with a similar problem they will catch bits of filter, etc and block prior to the IP failing.
I did read someone had a mesh filter in the IP pump, hope toyota put one in.
Chris

[Tim-HJ61 Donating Member Find all posts View Profile Close Tim-HJ61]

Re: Fuel filter problems

What are others doing for filters?......and heating before or after? What change intervals?

Even if the injector pump is absolute toast,,,,I have saved mored in fuel costs than the van is worth to replace. Still, I'd like to save it if possible.
So in this regard, does anyone have knowledge of Toyota pump internals, gauzes, degree of difficulty and any special tools etc......or even access to a manual.

Comments invited, cheers.

Maybe you could source a replacement pump and fit it, then take your time learning about doing up your main fried pump.

Regarding order of flow. I've got a plastic $2 filter, then the Heat exchanger, then the CAV. So the CAV and the main filter are getting heated oil. I'm using Valvoline filters just because I found them on special in Supercheap. I've been changing them at less than 1k intervals recently, but hope that will stop.

I had an odd occurence where the motor was running awful, yet the CAV filter was not blocked. However the main filter was blocked completely and when I sawed open the filter, it was filled with grey sludge. It puzzles me why the grey sludge was not trapped in the CAV, this was before I put the little plastic filter in. Grey sludge is apparently associated with algal growths; could they only live in the main filter??? or perhaps the CAV filter rated at 10 - 15 microns not catch the sludge?? Seems unlikely.

I HAD put some Chemtech additive into the fuel tank and that may have killed off some algae which made its way through the system, but I'm still suprised the CAV did not pick it up - that's why we have prefilters isn't it???

I put the little plastic $2 filter in place after putting some Gull Perth bioD in and wanted to catch any debris that may release. It's also easier to see the condition of the filter.

Tim

[tbird650 Senior Member Find all posts View Profile Close tbird650]

Re: Fuel filter problems

Thanks for the tips.

Yesterday, I backflushed the injector pump. It's significantly better now!
I guess I got outa jail on that one.

My system is remarkably simple, with the only mod being a p.i.p. heat exchanger. I start the motor and are easy on the throttle till warmed up. So, no additional tank or switching valves. I have run everything from A.T.F. ........lighter industrial oils.......to my favourite,,,WVO.
Cheers

[bruceT Senior Member Find all posts View Profile Close bruceT]

Re: Fuel filter problems

I'm new to these forums, having been introduced by Tony from West Oz via the OZVETS forum pages. (Thanks Tony!)

I've read this thread with interest as I've just purchased a Delphi 296 fuel filter. Does anyone have any experiences with the Fleetguard cartridges for this filter?

To be on the safe side, I think I might install a little fuel screen filter before the IP on my 1976 Merc 300D.

I am still sourcing all the bits for converting this car to run UCO.

Cheers
Bruce

[bruceT Senior Member Find all posts View Profile Close bruceT]

Re: Fuel filter problems

I picked up my 10 micron (rated) water separating Fleetguard filter last Friday. Here it is.

Head (Fleetguard 3311505S) $62.69 (incl GST)
Cartridge (Fleetguard FS 1221) $18.02 (incl GST)

The port threads are the same size as the CAV, ie. 1/4"NPTF. However, I have purchased elbows as the ports are on top of the head. Overall, the assembled unit is just a little taller than a CAV, and the mount holes are the same.



I fitted the filter on the w/e but have struck a snag which I think has to do with the filter media. These FS1221 cartridges have 10 micron filter media, but the engine is starving soon after changing over. The previous Fleetguard CAV media I was using before was also 10 micron and I had no such problems with fuel starvation, so I'm thinking that the water separating media must offer more resistance to the veg oil.

I cold filter through 5 micron filter bags and just let it drip through all the HMP build up on the walls of the bags (like Tony) and end up with nice clear honey-coloured oil. I also add 100ml of white spirits to each 25litre batch to help prevent gelling on cold mornings, so I'm confident it is not a plugging issue. I'll pick up the 15micron version tomorrow (not sure of the cartridge no, but think it is the FS1251) and see if that helps.

Has anyone else had such problems with water separating filters?

[Tony From West Oz Vice Chairperson of WARFA Find all posts View Profile Close Tony From West Oz]

Re: Fuel filter problems

Bruce,
Are you testing for water in your oil?
Is there the possibility that there is some water in your veggie tank?

Perhaps the filter is working correctly.

Water Blocking filters do just that, they block flow when water is absorbed sufficiently to wet the filter media.

Tony

[bruceT Senior Member Find all posts View Profile Close bruceT]

Re: Fuel filter problems

Bruce,
Are you testing for water in your oil?
Is there the possibility that there is some water in your veggie tank?

Perhaps the filter is working correctly.

Water Blocking filters do just that, they block flow when water is absorbed sufficiently to wet the filter media.

Tony

Hi Tony,
You scared me for a mo! No it's a water separating filter and I was told that water is merely collected by the media and drains off. Anyway, I popped outside and took a sample from the tank and did a quick crackle test. (Thanks, I'd just done the dishes!) Not a single "pop", so I can guarantee it is as dry as a witches tit.

When I operate the hand pump to prime the circuits, the WVO one seems to be harder than the diesel one. (Brand new filter cartridge in the stock head too)