Are the injectors gummed up?

[BV]

Why is my engine starving of fuel at low rpms? The engine has fuel injectors. (1977 Westy, 2000cc)

Last fall the engine was running fine. In November I put gas stabilizer into the fuel tank, but since I had already removed my battery, I did not bother running the gas stabilizer through the fuel system.

Now the engine runs OK at high rpms but not at low rpms. It seems starved of fuel at lower speeds. I have to pump the gas pedal vigorously to get it to start.

Could the injectors be gummed up? Would the fuel filter or fuel pump be effected by the untreated old fuel? Should I bring it to away for a fuel pressure test? Should I just drive it for a while with some injector cleaner in the fuel and with premium gas?

Thanks for any suggestions? BV

[Devastator]

Are you still running the gas that you put in it months ago?
Most of the problems you describe affect an engine at high RPM nore than at low RPM.
FWIW, most injectors don't get "gummed up" like the advertisements show. The filter baskets in them get full of junk, just like a fuel filter, (which is essentially what they are). You can buy new filter baskets for around $1.50 each on several websites.

[BV]

Thanks Devastator

The tank was only one quarter full. As part of my attempts to solve the problem, I have added 20 litres of premium gas and some "fuel injector cleaner." I have run it a few times for about 10 minutes each time. The engine is actually running a little better than when I first started. So I wonder if I run it more, and maybe add more new fuel, if it will continue to improve.

Thanks for the "fuel basket" suggestion. I will check out my Bentley service manual on that.

To get to the fuel filter, do I remove the shield between the engine and the gas tank?

Thanks again. BV

[Devastator]

I dont' know enough about Westy's to tell you where the fuel filter is located. You could post elswhere in this forum with that question. If you want to replace the filter baskets, however, I can tell you that they are located in the top of the injectors.

[BV]

Thanks, Devastator. BV

[Jadewombat]

The cheap method of injector cleaning:

http://www.youtube.com/watch?v=VFJlTfHyrUk

[SUbuggy]

Are you still running the gas that you put in it months ago?
Most of the problems you describe affect an engine at high RPM nore than at low RPM.
FWIW, most injectors don't get "gummed up" like the advertisements show. The filter baskets in them get full of junk, just like a fuel filter, (which is essentially what they are). You can buy new filter baskets for around $1.50 each on several websites.

sorry but this is absolute RUBBISH.

i have seen PLENTY of injectors get "gummed up" from sitting, the issue now is currently the worst i have ever seen it.

I see many marine engines that sit all winter, some with stabilizer, some without, it really doesnt matter. the injectors in some case simply flow ZERO fuel, or fuel flow can be reduced anywhere from 10-90%. also, the injector atomization quality suffers horribly.

i see this on as a symptom of the fuel we are now getting, and the blending of ethanol with it. i see this a lot on offroad engines too, where it sits between seasons.

soemtimes injectors can be saved, it just depends how long they have been sitting. an older injector with fuel from a few years ago might be fine, but a newer one with fuel as little as a few months old can clog really fast.

I use an ASNU flow bench to test and service all the injectors i work with.

The cheap method of injector cleaning:

http://www.youtube.com/watch?v=VFJlTfHyrUk

this is pretty much USELESS. all it tells you is fuel is capable of getting throw. thats it. what if you burn a hole in one piston becasue flow id down 30%? cant really measure that with something if this nature.

here's how i do it. you actually measure flow and atomization quality. makes all the difference in the world when you KNOW every cylinder is getting exactly the same quality and quantity.

[Devastator]

Quote:
Are you still running the gas that you put in it months ago?
Most of the problems you describe affect an engine at high RPM nore than at low RPM.
FWIW, most injectors don't get "gummed up" like the advertisements show. The filter baskets in them get full of junk, just like a fuel filter, (which is essentially what they are). You can buy new filter baskets for around $1.50 each on several websites.



sorry but this is absolute RUBBISH.

i have seen PLENTY of injectors get "gummed up" from sitting, the issue now is currently the worst i have ever seen it.

I see many marine engines that sit all winter, some with stabilizer, some without, it really doesnt matter. the injectors in some case simply flow ZERO fuel, or fuel flow can be reduced anywhere from 10-90%. also, the injector atomization quality suffers horribly.

i see this on as a symptom of the fuel we are now getting, and the blending of ethanol with it. i see this a lot on offroad engines too, where it sits between seasons.

soemtimes injectors can be saved, it just depends how long they have been sitting. an older injector with fuel from a few years ago might be fine, but a newer one with fuel as little as a few months old can clog really fast.

I use an ASNU flow bench to test and service all the injectors i work with.

I never stated that fuel injectors couldn't get gummed up or have deposits build up. I only stated that it's not very common. I've replaced the filter baskets on my injectors after they quit working, and that cured the problem. I also did the same to the injectors in my Jeep and they started working again too. To be fair, I also cleaned the injectors on the Jeep in an ultrasonic bath and flushed them both directions with cleaner. I guess I should rephrase my earlier statement to read: Most injectors do not simply fail. They won't flow fuel due to clogged filter baskets and/or deposits in them, particularly at the pintle.
It is a well known fact that Ethanol will dissolve the harsh chemicals in gasoline, (and in your fuel tank), and deposit them in the rest of your fuel system, particularly the injectors. My experience in converting from gasoline to E85, with fuel injection, the filter baskets caught the nasty crap that came out of the tank, while the rest of the injector continues to work just fine. It was well worth the $7.00 worth of fuel injector filter baskets to change them in comparison to replacing all 4 of the injectors. The fact that the engine, referred to in the original post, runs at higher RPM, indicates to me that the injectors are working just fine, although they may , indeed, need a good cleaning as the spray pattern at low RPM may also be causing a headache. Either way, running that old gas and fuel stabilizer combination out of the tank is a good idea in order to verify that it is not the culprit.
I apologize if my statements were misleading.

[Jadewombat]

Sooooo, ethanol blending has been around for how many years (since the 1980s) and it's only become a problem the last two-three??? I don't think so. Yes, we've all seen the 'No ethanol in our gas' more and more at mom and pop stations the last couple of years.

The only thing alcohol would do is dry out the rubber fuel lines and cause them to crack, if the mixture was severe enough pieces of the fuel line could come off. This isn't going to make the engine run like poop at a 10% mixture though. I've ran small engines with 50% mixtures and they still ran.

Ethanol, even in small amounts, is becoming the new scapegoat for everything that won't make an engine run.

[Devastator]

I converted my sandrail from gasoline to E85, (which is, up to 80%, not 85%, ethanol). When I did, the ethanol, which is a solvent, (see denatured alcohol), washed all the gunk out of my tank and stuffed it into the fuel filter. No big deal as I just changed the filter, but, yes, alcohol does "clean" out the fuel system. The blending done in the 80's was only about 5%, and has increased to 15% in the past few years. There's also been some nastier stuff added to the gasoline in the last 20+ years that alcohol will remove when added. I agree with you, however, ethanol gets a bad rap for the most part.

[SUbuggy]

im no petro-chemical engineer. but what i do know is the fuel is varnishing and clogging things up at a faster rate than ever before.

ANY of my customesr that run pump-based fuels, i clean and flow there injectors anytime thereengines site more than 90 days. i simply DO NOT have this issue with any of the racing fuels, or av-gas.

anyone that uses something "seasonally", i recomend the last tank of fuel be av-gas and dont have these issues.

[Devastator]

i recomend the last tank of fuel be av-gas and dont have these issues.

Not that it's the same subject, but similar.
When I stored my sandrail with AV gas in it, then switched to E85 on the next fill-up, a petroleum jelly ,(literally), formed on all of the jets, fuel injectors, filters, and pressure regulator. A petrolium engineer told me that it is a mixing of the ethanol with water and the chemicals found in all forms of gasoline. I had this happen on a carbureted engine and a fuel injected engine.

[BV]

Good news -- I found a vaccum hose that was disconnected. The engine now purrs like a content cat.

I had checked the hoses earlier, but had not noticed that this hose was partially disconnected -- it was not very obvious. I'm glad I made one more check just before I was going to look for the fuel filter.

Still, thanks for the discussion. I learned from it.

BV