RA Rodeo V6 fuel pump and lpg

[Utemad]

Hi all,

Has anyone had a fuel pump from an RA Rodeo V6 (Isuzu motor) apart?

My cousin's Rodeo fuel pump has failed. When it wouldn't start we pulled the fuel line off the filter and it was pumping but not much and eventually the flow stopped all together. I have it out of the tank now and have hooked it up to 12v. Sometimes it pumps but you can hear it is having a hard time of it. Other times it just draws current but will not turn like something is holding it back.
I have tried to pull the pump apart and have released all the plastic tabs but it will not come apart. I'd really like to get it apart to check for blockages and such as we priced a new one at $800

So has anyone had one apart and can tell me what I have missed?

This ute has also got LPG installed. It was aftermarket when the ute was about 2 years old but is the Holden certified lpg install. It starts on petrol and switches itself to lpg. Is anyone familiar with this installation and do you know if there is any way to start it on lpg?

Any help would be appreciated.

[bradley]

Hey champ, sounds like the pumps siezed due to bearings shittin themselves, made in thailand quality

Should be a goss direct replacement version available for a couple of hundred. Sheez even retro fitting a bosch motorsport 44 pump would only cost $ 350 odd.

Lpg - the systems i have seen use the coolant temp sensor and a time circuit to activate the lpg. similar to the start enrichment cycle in the ecu for the fuel maps. You might be able to trick the ecu for the lpg by using variable resistors etc. but i doubt it would work effectively. The design is to stop backfires etc.

Pump would be a non serviceable throw away item.

cheers Brad.

[Utemad]

Thanks Bradley. I hadn't looked aftermarket yet. Didn't think there would be one. However I did consider just sucking through the old pump with an inline pump. So long as it was within the 43-55psi bracket I thought it should work.

As for the dead pump it certainly is a sealed throw away item. However they never bet on the determined Aussie who didn't have the $800 to spend
I figured out what was keeping the bottom assembly to the upper assembly. I then had to cut the return hose inside the pump to get the pump apart enough to get at the motor. Then after testing the motor directly and seeing it definately is seized I managed to get the motor out far enough to pull it apart. This involved folding back some sheet metal and then beating it long and hard to get the motor and impeller out of its casing. Once out I noticed the brushes had worn a deep groove in the copper contacts (wrong way around I'd have thought). However as that wasn't the problem I was reluctant to touch that for fear of making it worse. Anyway I didn't notice anything wrong with the motor itself so I reassembled it loosely and powered it up and it runs fine. So I put it all back together and folded the sheet metal back over the motor end and it runs but not as well as it did apart. Just a little noisier but it runs fine.
We put it back into the tank and it pumped the tank dry. Got a little noisy when it got the fuel to about 1inch from the bottom of the tank but I think it will be better when the fuel return line is filling the plastic bucket part of the fuel pump assembly which I am guessing helps keep the motor cool and lubricated. More so than just fuel passing through the motor anyway as it ran fin before that.

I'll put the ute back together today and see how it goes. My cousin only does about 40km/week on petrol he reckons. Due to his lpg tank not being big enough to last his whole week (no lpg at work). Plus it starts on petrol of course. So hopefully this limited use will be fine. Plus I told him to kep his tank over 1/2 full all the time. He previously left it only 1/4 full.

We cleaned his tank out while we were at it and boy was it dirty! It had small rocks and dirt, blue flecks from something and even hair (dog fur?).
None of it was in the pump motor though. All stopped by that dodgy looking filter pillow inside the pump.

[Utemad]

Hey champ, sounds like the pumps siezed due to bearings shittin themselves, made in thailand quality

Which bearings would they be There weren't any bearings to seize! Perhaps part of the original problem?

[bradley]

Hey champ, sounds like the pumps siezed due to bearings shittin themselves, made in thailand quality

Which bearings would they be There weren't any bearings to seize! Perhaps part of the original problem?

Ahh yes, those bearing things cost money dont they should be able to make some more margin by getting rid of them


You could construct a simple suction pickup for in the tank and just fit a cheap inline walbro or bosch high pressure pump. only $ 200 or so. just make sure you isolate the mounts - the noise will drive you batty.

Does the fuel pump run the whole time even when it switches over to lpg? if so this would be what killed it, just cycling the same juice round and round combined with ambient temp would make the fuel get very hot and contribute to pump failure. maybe a question for the lpg kit makers.

[Utemad]

Just talked to the lpg guy. He said there is no way to override the system to start on petrol. Said as it was negative suction or something that it is best to start on fuel so you didn't have to crank it over so much to suck the lpg through.

Also said that the fuel pump runs all the time. Reckoned it was best to do that as stale fuel would otherwise kill the pump anyway and block injectors. What is the deal with stale fuel? I have heard of it of course but thought it would just make your engine run poorly. Didn't think it could clog and break stuff.

Called a place about the Goss fuel pumps and they are going to get back to me. So thanks for that little tip.

[DAZZ]

The fuel pump runs all the time to keep the injectors and fuel rail cool and to keep the pump from seizing. EFI vehicles must start on petrol to pass regulations (In Vic at least) Early systems did have an override to start on LPG but these may not exist anymore. Been a while since I've done LPG conversions.

Seen fuel get so stale that it turned into something like a varnish that seized the fuel pump solid. Even the fuel sender float and arm was stuck solid.

[Utemad]

Thanks Dazz.

What sort of time frames exist for fuel to go stale?

[DAZZ]

Don't really know. Would maybe depend on how much fuel\oxygen is in the tank.
This vehicle had not run on petrol for a long time.
I do know that PULP goes off real quick as the stuff in my zook starts to go off within 2-3 weeks. Don't drive it much....

[Utemad]

You could construct a simple suction pickup for in the tank and just fit a cheap inline walbro or bosch high pressure pump. only $ 200 or so. just make sure you isolate the mounts - the noise will drive you batty.

Just called Autobarn about these pumps. He reckoned a VL Commordore unit would be good but it seemed its max pressure was about 43 psi. Not good if the range we need is 43-55 psi. So he recommended a Bosch pump. Said it was rated to 700hp for $315.
If my rebuild job on this unit doesn't last though I'd rather go to an auto electrical place I use in Brisbane (I'm near Gympie at the moment). They'd have a far better range and price for their inline pumps.
Any thoughts on a particular pump?

[bradley]

sounds like a bosch 044 he quoted, bit of overkill, unless you want to push 10psi of boost into it as well mmmmm 400kw rodeo

Walbro pumps are cheaper than bosch and very good.

try www.powerflowinjection.com 1300 880 928 (melbourne)

Either use the original pump wiring or run a new circuit with 10-15 amp wiring and relays etc. Fuel pumps need lots of current and little voltage drop to operate correctly.

Im sure older lpg systems had a purge valve up front to get them started quicker.

OH well.

Shiza Dazz how old was that fuel !! i would think that the start / warmup cycle would be enough to keep it sweet. Whats the reasoning with the fuel rail temps etc. all the components are built to handle engine temps anyway and as the injectors are not powered up the pintles are closed so i cant see it doing any harm. Long term yeah the injector tip may get some build up on it, but used for say 4 start cycles a day it shouldnt be a prob.

just curious mate.

[DAZZ]

Was told this when I done an LPG installers course. Suppose to control seals and o-rings from becoming heat affected and to stop fuel varnishing in the lines and injectors, again due to heat. The fuel will be cool when in the tank. Must be some truth in it I suppose!!!!

This vehicle was pre- auto change over and the didn't run it on petrol at all for years. We had to change the tank, lines, pump and everything to do with the fuel system

[Utemad]

ok another question

I have looked up the site Bradley mentioned before. They have some pumps for $200 that sound like the go.

They have a Walbro GSL393
It is a 3 bar 120 LPH unit (LPH = litres per hour?)
They also come in 3 bar 190 and 250 LPH units. I'm guessing for a stock V6 Rodeo the 120 unit is fine?

They also have a Bosch 0 580 254 070
3 bar 165 LPH
Says it flows at 130 LPH at 3 bar.

Since they are both $200 which one would you guys think are most suitable?

Also 3 BAR = 43.511 PSI at 0 FT Above Sea Level and 4 BAR = 58.015 PSI at 0 FT Above Sea Level. So with a 43-55 psi range to work in would you think it is better to aim low or high? These units are both 3 bar so working in the bottom end of the range. Can get a Bosch in 5 bar but that is too high.

Also the Bosch is just over twice as heavy as the Walbro at 1.1kg. Why so?

As for switching off the fuel pump when on lpg I was only thinking if doing it to extend the life of my rebuilt one. However if I install one of these external ones then it is a non event. We're just about to connect the tank to the vehicle and see if it starts.

[Utemad]

Well guys we fitted the pump into the tank a few hours ago and it started first turn of the key

We let it run for a bit before we bolted the tank back up and test drove it.

So all is good but I am not too sure how much longer it will last. There really are no guarantees when you do this sort of thing. I'll find a source for an external pump and keep their details handy just in case
At least it should get him home tomorrow......maybe.

Thanks for all your help.