Bogging at higher RPM, fine for a while after rest

[jessef]

Running 80% veg / 20 % diesel.

Running on the highway for a while, it runs great.

Usually under load driving uphill and/or high rpm, it will bog down and eventually coast to a stall at the side of the highway.

Pull over and let it sit for five mins and it fires up and drives fine until I push it up a hill again.

Works like clockwork on reg diesel.

Have not changed the fuel filter out yet. Will do that tomorrow.

Starting is not an issue. Turns over like it was born to run 100% veg.

Just found the bogging issue while I was on the highway.

Not a Delica but a Nissan Safari Same diesel/pump system as the Deli's.

Thinking I need an inline pump by the tank as the IP can't keep up.

Thoughts ?

[delicat]

Hey Jesse,

It's simply sounds like a fuel starvation. Your veggie is probably clogging the fuel filter. Do you have a sight filter before the stock fuel filter? That would be the 1st thing to jam. I've had a similar issue with my Delica when I had a in-line filter before my in-line fuel pump just after the tank. I ended up removing this filter, cleaning my in-line filter pump and never had a problem after. As mentioned before, (somewhere else...) I'd drain some of the veggie from the tank and replace with diesel, before changing the fuel filter (if you don't have another filter on hand just run diesel through it, I bet you'll be able to re-use it...).

Cheers
David

[mararmeisto]

Concur with delicat - sounds like your IP is drawing faster than the WVO can be sucked. How much further aft is your veggie tank than the diesel one? You might need a booster pump or an inline heater.

[delicat]

I think he's only blending... no 2nd tank involved. But 80% veggie, that's already good he gets away with it, almost...

[jessef]

It's IP. Not enough suction.

Will need to put an in-line pump.

Apparently the pull on the IP on the Safari's aren't too good and an in-line pump even with 100% diesel gives a good increase in smooth power up a hill.

Makes sense. Pump is pushing fuel which eliminates air in the system as opposed to the IP pulling which can bring in air.

[loki]

It's IP. Not enough suction.

Will need to put an in-line pump.

Apparently the pull on the IP on the Safari's aren't too good and an in-line pump even with 100% diesel gives a good increase in smooth power up a hill.

Makes sense. Pump is pushing fuel which eliminates air in the system as opposed to the IP pulling which can bring in air.

I would recommend also adding a short cut around the ip either to the return line or even back into the supply line before the pump to make sure you don't damage your ip with too much pressure, this could be a bit on the paranoid side but was part of the instructions that came with my WVO kit.

[mararmeisto]

I think he's only blending... no 2nd tank involved. But 80% veggie, that's already good he gets away with it, almost...

You're right... missed that in the original post. Still, WVO is as thick if not thicker than WEO so I wouldn't want to do a full blend unless it was middle of a warm day.

An inline heater should still help. Heating the diesel won't be an issue, and it'll definitely help the WVO.

[Kuan]

I'd be really careful about running that much WVO without a preheat on it. In the long run you could damage the engine. The viscosity is just too high to achieve complete combustion.

[after oil]

i always add an assist pump when i do installs as per recommendation of the manufacturer of the kit i use.
another thing to consider is an obstruction in the line somewhere. i once found a flap of plastic (the marine grade hose was lined for some reason) that obstructed only on wvo and only under load

[jessef]

I'd be really careful about running that much WVO without a preheat on it. In the long run you could damage the engine. The viscosity is just too high to achieve complete combustion.

You are referring to initial startup.

This engine loves wvo and burns it nicely.

I don't have any issues starting up in the morning this summer.

The weather is hot and the truck starts well on wvo.

My preheat is the 40 degree temperature outside as well as the 24V industrial NA 6cyl IDI engine in the Nissan Patrol.

Also the stock fuel lines are 3/8" and the fuel filter/pickup is massive.

This is not a run of the mill vehicle.

It was designed to be used in very harsh conditions with different grades of diesel ranging from dirt poor to crystal clear refined.

[mararmeisto]

I'd be really careful about running that much WVO without a preheat on it. In the long run you could damage the engine. The viscosity is just too high to achieve complete combustion.

From what I've read, generally not an issue once the engine is warmed up: there is enough heat in the injection pump to warm the oil sufficiently before injection to lighten the viscosity.

That being said, drawing cold WVO from the rear of the vehicle to the forward would probably benefit from a booster pump. Especially on these weak-kneed Safaris. Sorry Jesse, had to take the cheap shot.

[jessef]

[newwestman]

What pumps work best as a booster, and cost effective?


thanks
Lawrence

[jessef]

What pumps work best as a booster, and cost effective?


thanks
Lawrence

The term best and cost-effective are relative to the size of your wallet.

Walbro FR series pumps are around $80-120 and are used in many applications. The best thing about that model is if the pump fails, fuel will still flow through it so you don't get stuck with a blocked pump and the IP can't pull from the tank.

There are many cheap, moderate and expensive pumps out there.

Depends on what you want and how much you'd like to spend.

[Luna-Sea]

Hey,
I would agree that a pre-heat would be really
beneficial for lowering the viscosity of the wvo,
as well as moving it a little closer to combustion temp,
also minimizing build up of unburnt wvo.
Perhaps an auxillary pump then an inline heater
(Veg-therm,glow plug ect.)and/or a heated filter set-up
(Veg-max,heat-exchanger type).

I suspect the mix Fuel (80%wvo-20%Diesel) is just
too thick for the Injector Pump's lift pump and
the timing advance valves in the pump.50/50 is
the most I have done and read about. I would fully
agree fully that the engine/IP/injector combo is way more robust
than our delicas(rub-it-in ) but there are limits(damnit!).
Just cut back on the mix until you dial it in a bit more,like I know
you will!Let us know what mix percentage stops the bogging eh!

Fly on veggie Icarus!

Right On!