1990 HiAce/Hilux fuel pumps

[Craig Laurendet Biofuels Forum Newbie Find all posts View Profile Close Craig Laurendet]

A couple of months ago I converted my HiAce van to run on WVO, in prep for a big road trip at xmas.
After 1500km’s running on WVO, my fuel pump started to leak (as expected) so I had it rebuilt with the proper nylon seals.

However the mechanic said, in addition to the predictable degradation of the rubber seals… There was a glue like build up clogging the pump. (And he would not give a warranty if I kept using oil)
Also I had 'Stalictite' like deposits hanging of my injectors.

Has anyone experienced this problem with residue build up in the pump?
Do you think a drop in temp attributes to the ‘Glue’

I filter my oil through a pair of pants and then through a 1 micron filter.
I heat it to 70 degrees. The heater is approximately 1m away from the pump, although the hoses are fully insulated.
I have a 1990 2.8L engine with a rotary pump…Bosch I think.

Any sugestions would be welcome.

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

Re: 1990 HiAce/Hilux fuel pumps

Are you cold filtering? I'm wondering if the "glue" is fat residue. Some animal fats are known to be high melt point. I had this problem with one oil lot. It was sticky, sticky, sticky!! Inevitably most if not all of our vege will have some in it.
I think you will have to run a blend as I haven't been able to totally remedy the injector coking problem either. Next I am trialing 70%vege/ 30% diesel.

[Guest Close David]

Re: 1990 HiAce/Hilux fuel pumps

I don't know what your mechanic's definition of " glue" looks like but this is what the pickup in the tank on my car looked like before any veg even got near it.



Even though the tank was removed from the car there has still been a lot of stuff coming out of the fuel lines and maybe even the pump since I have been running bio and a veggie/unleaded blend. This is just the crap that was already there so it may be a very worthwhile thing for you to pull the tank and clean it out to start with.

It is good practice to settle your oil and then only use the stuff that comes to the top which is the most liquid oil and best suited for running in your engine. I pump the clear oil from the top of the 20L tins I get till I hit any fats into 60L drums to settle again and rotate the order of the drums I draw from so they all get at least a month to re settle.

What are you starting your engine on? If you are starting it from cold on WVO before the engine and the WVO has had a chance to warm up, this could be the cause of the deposits on your injectors. If you are going to run a single tank system only, running a blend is your best option to prevent this. On the other hand, If your pump wasn't working properly before the rebuild, it could have been producing a poor spray pattern into the cylinder which may also account for the danglies.

If you are going to blend, I suggest you have a read of the recent thread on this here and look it up on the info pop site where there is a lot of other info as well.

[Craig Laurendet Biofuels Forum Newbie Find all posts View Profile Close Craig Laurendet]

Re: 1990 HiAce/Hilux fuel pumps

I am cold filtering my WVO, as I thought this would get more fat out of it, In any case I only use the top oil out of a can that has been left to settle.
Maybe I should filter it twice?
Is there any test you can do after filtering, to see if there is any fat left in the oil?

I start on Diesel untill the engine is warm and flush the system a couple of minutes before shutting down.

Pretty graphic pic... Might give my diesel tank a clean....

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

Re: 1990 HiAce/Hilux fuel pumps

I doubt that the IP "glue" is related to high Melting Point oil.
Is your oil dry? Have you tested for water?

I feel that this may be a result of water contributing to polymerisation of the oil. A proportion of the polymerised oil, attached itself to surfaces in the IP, resulting in the "glue". This may have also contributed to the coking of the injector tip.

Do you have samples of the "Glue" which could be sent for chemical analysis?
This would provide a definitive answer to your dilema.

Tony

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

Re: 1990 HiAce/Hilux fuel pumps

I doubt that the IP "glue" is related to high Melting Point oil.
Is your oil dry? Have you tested for water?

I feel that this may be a result of water contributing to polymerisation of the oil. If some of the polymerised oil, attached itself to surfaces in the IP, this may result in the "glue". It may have also contributed to the coking of the injector tip.

Do you have samples of the "Glue" which could be sent for chemical analysis?
This would provide a definitive answer to your dilema.

Tony

[Craig Laurendet Biofuels Forum Newbie Find all posts View Profile Close Craig Laurendet]

Re: 1990 HiAce/Hilux fuel pumps

unfortunately I don't have any samples of the reidue.
I guess I will just drive around a bit and then have a look.

I only do a spot test for water. So it is very possible water is the problem.

[Craig Laurendet Biofuels Forum Newbie Find all posts View Profile Close Craig Laurendet]

Re: 1990 HiAce/Hilux fuel pumps

I bought a heat gauge today & had a bit of fun driving around with it at different spots.
I found that although my inline heater (Thermo-Veg or something), heats up to a wopping 90 deg C, it only heats the oil to about 50! And by the time it gets to the IP its down to about 40-45.
Funnily enough it heats back up to 55 befor going into the injectors.
So I guess some additional heating is DEFFINATLY required.

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

Re: 1990 HiAce/Hilux fuel pumps

I got best results by running a looped return and having the GP heater at that point of loop. That's in the engine bay, just where the original filter used to be.....all with foam insulation. It has a 100C button thermostat from Jaycar.
The injector line heaters are good for approx 20C extra heat and draw 2amps per cylinder via a relay.

[Craig Laurendet Biofuels Forum Newbie Find all posts View Profile Close Craig Laurendet]

Stalling problem

I've now re-routed my coolent through my veggie tank. In conjuction With my in-line heater the tempurature going into the IP is 70 deg C (158 F).

I have found that after 1 hour of driving on vegtable oil my car experiences a stalling problem.
The situation happens when I have been travelling at pretty constant rate of 3000rpm & then slow down fast (So the engine is only doing 1000rpm). When this happens my engine tends to stall or feel out of time.
If I switch back to deisel the problem stops.
I have a new oil filter & there are no blockages in the lines

Dose anyone have any suggestions as to why I only experience this problem on veggie oil & not diesel?

[Guest Close David]

Re: 1990 HiAce/Hilux fuel pumps

Does your Veggie tank have an air vent?
My guess would be that if there is no hole or the vent is blocked,my guess would be that the IP is able to pull the liquid and create a vacum at speed but once the revs and draw of the pump drops, the vacum is too great for the engine to get enough fuel to get back up to speed and it then stalls.

Other possibility could be that the pickup in your tank is getting blocked with crap in the tank. At high speed the debris is drawn up and blocks the screen. Once you go to diesel the draw that sticks the rubbish to the screen stops and the rubbish drops back into the tank till you start pulling fuel from that line again.

Just a couple of suggestions that you may like to check out.

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

Re: 1990 HiAce/Hilux fuel pumps

Sounds like fuel starvation......!! See my other posts for details and see all the steps I went thru while wrestling with this problem. It seems that our Toyotas are a very different kinda beast to that of the Mercedes. Good luck.

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

Re: 1990 HiAce/Hilux fuel pumps

Could it be air leaking into the system? I am finding on my toyota leaks leak air in, rather than oil out as on the mercedes. I believe some air will go through the injectors ok, but not a lot, and it may vary with speed.

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

Re: 1990 HiAce/Hilux fuel pumps

Could it be air leaking into the system?

Most likely yes. Air leaks are directly relative to the degree of "restriction" in the fuel lines, filter and tank system.
A clear portion of the return line to the diesel tank is an excellent way of determining the amount of air that becomes trapped while the fuel lines are in loop mode.

Switch from loop mode to tank return mode..... immediately observe if there's a stream of bubbles.

Concentrate on reducing fuel restriction. Trying to seal it more and more is sort of like chasing ones' tail.

There are some options:
1/ Reduce viscocity of the fuel.
2/ Increase capacity of any "on demand" filtration.
3/ Increase the size of fuel lines.
4/ Reduce the amount of fat in the fuel.
5/ Move the point of filtration to "tank entry" rather than "tank exit"

There's pros and cons to each of the above solutions. Combine 2 or 3 ideas to get a result?..... and do what works for you.

Happy vege cruising and have a great 007 new year!

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

Re: 1990 HiAce/Hilux fuel pumps

Most likely yes. Air leaks are directly relative to the degree of "restriction" in the fuel lines, filter and tank system.
A clear portion of the return line to the diesel tank is an excellent way of determining the amount of air that becomes trapped while the fuel lines are in loop mode.

Switch from loop mode to tank return mode..... immediately observe if there's a stream of bubbles.

Concentrate on reducing fuel restriction. Trying to seal it more and more is sort of like chasing ones' tail.

There are some options:
1/ Reduce viscocity of the fuel.
2/ Increase capacity of any "on demand" filtration.
3/ Increase the size of fuel lines.
4/ Reduce the amount of fat in the fuel.
5/ Move the point of filtration to "tank entry" rather than "tank exit"

I have an issue with this option. The fuel should be filtered before adding to the tank. This filtration should be finer than the vehicle main fuel filter. The vehicle main fuel filter should be to stop contaminants (created in or added to the tank, from reaching the IP.

There's pros and cons to each of the above solutions. Combine 2 or 3 ideas to get a result?..... and do what works for you.

Happy vege cruising and have a great 007 new year!