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tbird650
1st March 2012, 06:59 PM
Over the last week I've been upgrading the fuel delivery from the tank to filter.
It comprises:
10mm fuel line including pick up.
A low pressure piston pump 12v by Facet.
A gauge on the filter housing.

Doing the pickup was the worst part. I had to bend some tube exactly the right shape, then braze it in to the tank adaptor.
Fiddly and the tank had to come out.

I needed to increase the flow of fuel and this mod currently improves power and hot starting.
The pump isn't really up to the task and does lag at full load. The gauge also shows it will be at 1 or 2psi
at idle but under accelaration, the psi will go into negative. So, there's a some vacuum from the pull from the IP lift vane-pump.
The fuel is noticeably heavier though the van will run fine on it, it does eventually starve the IP.
Ok, so I need a bigger volume pump. 12V and means of regulating the pressure or self regulating.
A few PSI is all it'd need and it wants to be at a positive reading at all times.

What's working out for others as a reliable unit for a pusher style of pump? Logically, I'm thinking gear or vane because
I'm pumping oil that's heavier than diesel and that's significantly more viscous than petrol as well!
I'll do a forum search after I post this...

Thanks

JoeG
1st March 2012, 07:52 PM
Just purchased one of these for my Hilux (HI FLOW Electric Fuel Pump ULP & Methanol, havent fitted it yet, time will tell if it works on straight WVO
regards

tbird650
1st March 2012, 08:48 PM
Oh OK, I think you mean this PUMP (http://www.ebay.com.au/itm/HI-FLOW-Electric-Fuel-Pump-ULP-Methanol-/320857280358?pt=AU_Car_Parts_Accessories&hash=item4ab4958f66)
It looks to be a Holley copy. I suppose it's Chinese made. Great price!
Please let us know how it goes.
Thanks

JoeG
1st March 2012, 10:22 PM
Yes that's the one just picked it up and building a duel fuel system on my Tractor and Hilux so a while till I get results, but the pump is way bigger and heavier than the existing electric lift pump I useon the tractor and it's been on for a while, only just started blending and now looking at twin tank.
Lots to twiddle and play with but all good stuff, at least with the tractor if it stops it's already home so easy to flush the fuel and start again, so it will be the test unit and Hilux (3L) engine 2nd
Regards
Joe


Oh OK, I think you mean this PUMP (http://www.ebay.com.au/itm/HI-FLOW-Electric-Fuel-Pump-ULP-Methanol-/320857280358?pt=AU_Car_Parts_Accessories&hash=item4ab4958f66)
It looks to be a Holley copy. I suppose it's Chinese made. Great price!
Please let us know how it goes.
Thanks

Tony From West Oz
1st March 2012, 10:56 PM
I tried one of the Holley Blue pumps and a Chinese copy as fuel pumps for my WVO but it had an issue with the viscosity of the fuel. I swapped it to the start tank and used the external lift pump on the IP for the veggie oil.
Why don't you install a 12mm black nylon air hose as the fuel line from the tank to the engine bay and reduce down at both ends to suit the existing hardware there. This will virtually eliminate the flow restriction in the stock fuel line and your IP will happily suck the oil from the tank.

You do not need a positive pressure at the rotary IP (they never have it on Diesel fuel), but you never want to get to a vacuum of 10mm Hg for any length of time, otherwise IP damage can result.
The large bore fuel line should eliminate the chance of a high vacuum at the IP, providing you have a veggie fuel heater before the fuel filter.

Regards,
Tony

tbird650
2nd March 2012, 07:50 AM
I tried one of the Holley Blue pumps and a Chinese copy as fuel pumps for my WVO but it had an issue with the viscosity of the fuel.
Tony, is this because there's a strainer inside the pump causing restriction? Can you explain the issues please?
A thought with this pump is to reduce the effectiveness by reducing voltage so that it only delivers slightly more than the max required and relieving the surplus.
With the heavier payload, I wondered whether it would heat up excessively and the armature is not fuel cooled on those.


The large bore fuel line should eliminate the chance of a high vacuum at the IP, providing you have a veggie fuel heater before the fuel filter.
Ok, I have 10mm airline for most of the length from the tank and of course no fuel heater. I'm looking for a solution with a blending approach so don't
want to add heat if I can get away without. I could try eliminating the pump altogether as it maybe adequate without now with bigger lines.
However, I have tried pulling directly out of a container alongside the filter and it's not totally effective either.
The problem can be sorted with extra ULP, I know but am wanting to stretch the limits. Also looping the return partially fixes the issue but creates power loss
after the engine warms up. Whatever the reason, the van goes with best power when the fuel supply is cool, though after initial warmup.
Part of the problem could be of my own creation with the enormous filtration housing. It stands higher than I'd like, perhaps being a half metre above
the IP and tank. One possible solution could be to lay it on its' side.

Another thing I thought of was to have the fuel tank higher than the filter and have gravity feed. However my days of tanks inside the van are over.
There's too many fumes and the more ULP the worse it gets.

I wonder whether a larger piston pump of the same type I have would be more effective. I see other ones rated for more flow. Mine is 95lph rated & 1.5 - 4psi.
Others I think are 130lph? Both these are petrol figures. My flow was tested last night at just 130 seconds for a litre. It would appear to only need a small increase.

tbird650
2nd March 2012, 12:49 PM
Plan B...
Ok, so I had another thought. Because the filter is large, possibly 3 - 4litres, I could treat it as though it's a header tank.
I could run an overflow tube back to the tank so that effectively there'd be neither pressure nor vacuum in the filter vessel.
During times of high useage, the vessels' level could be allowed to drop. Because its' vented there'd be no build up of vacuum to restrict the IP.
So, even with zero feed to the header, a range of 30+ km's would be possible but because there is feed, although slow, the vehicle
range increases. The pump does catch up at times of idle/slow running and also there'd be no pressure in the header to restrain inflow either.
This is a swirl tank that would double as a filter housing.
I scratched around and found the pic of the filter and strainer so those who've no idea what I'm refering to can visualize.
Immediately I can see it's had a revision. There's another 1/8BSP fitting on top which will be overflow.
Inlet is at top, outlet is under.
While the idea might work, I'll still look for a better pump. So any suggestions for pumps? My search showed
someone tipping the Carter vane 4600. They have fuel cooling the motor internals. 3/8"NPT fittings.
A massive delivery of US100GPH (freeflow) From AU$98 ....if it lasts well, then maybe worth it.
http://i1188.photobucket.com/albums/z414/3by7/mkj005-1.jpg

Tony From West Oz
2nd March 2012, 10:33 PM
Tony, is this because there's a strainer inside the pump causing restriction? Can you explain the issues please?
A thought with this pump is to reduce the effectiveness by reducing voltage so that it only delivers slightly more than the max required and relieving the surplus.
With the heavier payload, I wondered whether it would heat up excessively and the armature is not fuel cooled on those.


Ok, I have 10mm airline for most of the length from the tank and of course no fuel heater. I'm looking for a solution with a blending approach so don't
want to add heat if I can get away without. I could try eliminating the pump altogether as it maybe adequate without now with bigger lines.
However, I have tried pulling directly out of a container alongside the filter and it's not totally effective either.
The problem can be sorted with extra ULP, I know but am wanting to stretch the limits. Also looping the return partially fixes the issue but creates power loss
after the engine warms up. Whatever the reason, the van goes with best power when the fuel supply is cool, though after initial warmup.SNIP
I had checked the strainers in both pumps, just in case. I did have a strainer block much more recently on my start tank and it was not hard to clean it out, but a PITA to refit the strainer mesh. I just left the strainer out and installed a prefilter for the pump.
The issues I had were that I could not build fuel pressure until the fuel in the tank had warmed up significantly. I was never able to run the pump with cool fuel. By using the lift pump on the IP, I was able to deliver plenty of fuel pressure to the IP when using veggie. I had no issues with biodiesel being pumped by the Holley or Chinese clone of it.

I would be reluctant to simply reduce the voltage to the pump motor as this will drop the torque of the motor rapidly and if you don't have a pressure gauge, or don't see the fuel pressure drop, you could cook the motor of the pump. A Pulse Width Modulating Speed Controller should work fine, but it will not drop the pressure (pressure is regulated by the bypass valve spring).
Change this spring for a weaker one and you will drop the pressure. It is possible to grind off a little of the spring, so that when at rest (outside of the pump relief valve housing, it is shorter than before. Re-assemble and check the output pressure. Cut a little off at a time until you have the desired pressure. Whenever you re-assemble the pressure relief valve, ensure the cut end is not against the ball that forms the valve, so that it seats well on the spring and is not scratched by the cut edge of the spring.

I hope this helps,
Tony

Tim-HJ61
3rd March 2012, 12:22 AM
Airline is measured on the outside.
Rubber is measured on the inside

I suspect 10mm airline is really about 8mm internally
I imagine 12mm airline is really about 10mm internally.
I have 12mm rubber feeding my 4 litre turbo Landcruiser, and whilst I advocate for 12mm for all cars, in reality, 10mm rubber or 12mm airline would probably suffice for a 4cyl IDI with no return flow.

The tick tick Facet's are useless on WVO IMHO, as you have found.

You could also add a low capacity heat exchanger, such as a 10 plate, or a helton shower unit, down the back near the tank and warm the oil in the fuel hose, therefore thinning it.
I'm a non pump man myself. To me, if you can resolve the flow issue with hose sizing, maybe a heater, maybe hose in hose heated lines, then you can have a happy IP with good fuel supply ready for it to use without the constant running of a pump. If a pump breaks down, they can block the flow off altogether, leaving you stranded, or at least messy from removing it - in the dark, whilst it's raining, and the kids are late for their best mates birthday party...... :-)

Given you've had a painful time replacing the pickup in the tank, I'd not worry about going through that exercise again, but 12mm airline instead of 10mm will certainly help.

Tim

tbird650
3rd March 2012, 07:33 AM
All good thoughts, thanks.
Tomorrow I go drag racing, if the weather permits. So I'll be travelling an hour+ each way.
I'm interested and quite curious to see whether this recent change is of any benefit.
Will post early in the week with findings.

tbird650
11th March 2012, 09:14 AM
Ok, the life of an alternative fuel blender was not meant to be easy...

The morning of the aforementioned drag racing, I set off. Van immediately responded with a top speed of 20km!
My heart sank... I needed to be drag racing.... and it was the final round of the particular series!
It was an unusually cool morning for March. I stopped a few km away and lifted the top off the header tank.
Sure enough... empty! Fuel was trickling in but presumably too slow. So I top it off with a couple of litres.
All went well for the next hour. I rechecked the header tank level at the drags and topped it right up again. Drove home.
I had to work the following day and I headed off. I was nearly at the worksite and the lift pump pressure gauge was
giving the occasional random flicker with heavy acceleration. I reason it's starving or has introduced air so I threw
15litres of diesel in on the return trip that afternoon. Two things happened.

The header tank was getting to the point of overflow and so sending some fuel out the vessels' return line. It appears the extra diesel
had created a fuel blend thin enough that the Facet pump was now able to keep up.

Unexpectedly, the engine wouldn't hot re-start well at all. After several episodes of frantic cranking, I remembered the failing IP
syndrome reported where the lift fuel pressure isnt adequate on diesel. (I'd coined diesel the colloquiallism, 'weasil piss')
I'd solved this before by reverting back to the heavier blend the IP was accustomed to.

Anyhow, I decided to continue using blends with viscosity of weasil piss and get some kind of comparison.
I decided to adjust the IP pressure to suit. It was around this time that I discovered the circuit feeding the glow plugs was dead.
This must have happened quite recently as the cold starts had been perfect.
As I write, I still haven't sorted the GP relay/wiring issue. A can of ColdStart is sorting the symptom for now.

It seems clear that IP days are numbered however adjusting the lift pressure has been a great way of staving off the inevitable
and getting considerably more use from a worn IP. I've had this van for 6 years in May and would have saved significantly more
than the van is worth, so I'm not grumbling.

Hopefully my experiences are helpful to readers.