Engine hesitation- Mechanical fuel pump issue? 1500 engine

Just to clarify. New fuel lines proper spec fitted recent by PO.
Carb fuel filter is gauze and blown out at low pressure.
The carb has not been tanked/chemically cleaned. See no point in doing this (time/money) until the underlying fault is found.
Latest road test 84 miles. All went well for 79 miles (longest by far) and then the idle became erratic but did not stall.
This to me indicates there is something nasty in the fuel. When I last checked the pump pushing fuel out of the hose to carb the fuel was a slightly golden in colour, so thinking stale fuel. Ran without the inline filter this time. Also more stable running temp so must be a good sign of not running weak until the erratic idle started. Should I drain the fuel tank, is this a difficult job assume can do with a siphon pump.
 
You might get it siphon out. A simple siphon transfer bulb can do the trick
How old is the fuel? When I store my car I put in marine grade fuel preservative. When I start running it again in the spring I try to burn through the tank as soon as possible. I have drained it and used it in my lawnmower which doesn’t much care.

Completely removing and cleaning the carb would take less time than you have spent so far fiddling with this and that.

high quality fuel filters will save you a lot of pain in a carbed car. It is one of the places where cleanliness is next to godliness or at least pain free running.
 
In looking back at my last comment it comes across a bit dickish, it wasn’t meant that way and my apologies if it was taken that way. I will let it stand unedited as a reminder to myself to not be quite so brusque.

Looking forward to seeing further progress.
 
How to get the fuel out of the tank, which may be old/stale and causing blocking of the idle jets (darker in colour than new petrol) .
You cannot get a tube into the petrol filler because of a baffle or other obstruction.
You cannot get any tube into the tank outlet (ID to small).
This is telling me you cannot siphon fuel out so need to pump out. Do not want to use the mechanical pump so thinking of buying an electric one to pump fuel out of tank.
Anyone done this?
 
eng622 said:
How to get the fuel out of the tank, which may be old/stale and causing blocking of the idle jets (darker in colour than new petrol) .
You cannot get a tube into the petrol filler because of a baffle or other obstruction.
You cannot get any tube into the tank outlet (ID to small).
This is telling me you cannot siphon fuel out so need to pump out. Do not want to use the mechanical pump so thinking of buying an electric one to pump fuel out of tank.
Anyone done this?
Click to expand...
Pull the fuel sender. You'll have plenty of access and you'll be able to get a good look at the condition of the interior of the tank as well.
 
I concur on pulling the sender out. You can certainly siphon it from there and get a look at parts of the tank. In my case, it looked better from that vantage point than it really was. I ended up pulling the tank to give it a thorough cleaning. If I had known it was that easy to pull the tank, I would have done it from the start instead of hoping I sufficiently cleaned it in place. My problem was that I got it clean enough for it to run well for a week or so until the fresh tank of gas started to dissolve the crap inside and put it in solution. One day I went to start it and the first fuel filter went from perfectly clean to dark brown in a few seconds. After I got the tank out, I filled it with OxyClean and hot water and let it sit over night. That got rid of 99% the stuff inside. I did one more overnight fill and the inside looked brand new after that. There were areas inside that I thought might have been rust but turned out to be built up gasoline deposits. In fact, after the metal in the tank was clean it beaded water on the inside surface but never started to rust. It looked like they may have coated them at the factory.
 
eng622 said:
How to get the fuel out of the tank, which may be old/stale and causing blocking of the idle jets (darker in colour than new petrol) .
You cannot get a tube into the petrol filler because of a baffle or other obstruction.
You cannot get any tube into the tank outlet (ID to small).
This is telling me you cannot siphon fuel out so need to pump out. Do not want to use the mechanical pump so thinking of buying an electric one to pump fuel out of tank.
Anyone done this?
Click to expand...
You can simply remove the - fuel out of the tank (and into the fuel pump) hose - and replace it with a new long section of hose connected to an electric fuel pump. Make the new hose long enough so that it hangs over the side of the car. You probably want the electric fuel pump to be lower than the bottom of the fuel tank. I like to use a jumper box to power the electric fuel pump when doing this.
Pump the old gas into a container and burn it in your lawn mower or burn it off on a brush pile.
I suggest you place a fuel filter between the tank outlet and the electric fuel pump. That may help protect the pump and if you use one of the clear plastic ones you can see if it collects any gunk.
As long as you're at it you might try flushing out the tank a bit by adding some good gas once the old gas is out, then pump that out to "flush" the tank a bit. If you get debris in the filter during the "flushing" event - you're likely in store for a tank refurb - or replacement.
 
MikeHynes said:
You can simply remove the - fuel out of the tank (and into the fuel pump) hose - and replace it with a new long section of hose connected to an electric fuel pump. Make the new hose long enough so that it hangs over the side of the car. You probably want the electric fuel pump to be lower than the bottom of the fuel tank. I like to use a jumper box to power the electric fuel pump when doing this.
Pump the old gas into a container and burn it in your lawn mower or burn it off on a brush pile.
I suggest you place a fuel filter between the tank outlet and the electric fuel pump. That may help protect the pump and if you use one of the clear plastic ones you can see if it collects any gunk.
As long as you're at it you might try flushing out the tank a bit by adding some good gas once the old gas is out, then pump that out to "flush" the tank a bit. If you get debris in the filter during the "flushing" event - you're likely in store for a tank refurb - or replacement.
Click to expand...
Exactly what I meant, using the existing fuel outlet to the carb to get it out. You can get one of those siphon pumps (basically a sqeeze bulb with a simple one way valve to generate suction) to attach to the tank outlet.

Removing the sender is also easy, just lube the tiny threads first as you don’t want to snap anything off. The assembly is behind the plastic cover where the fuel lines come out.

It would be good to get a gander at the interior of the tank to see what is really in store for you. Just don’t use a match to look inside :)
 
eng622 said:
Stared this morning but still wont idle. So took carb top off and pleased to see fuel in the bowls (having set the float drop). Took the idle jets out and blew out with compressed air. Put all back started and now a smooth idle. No road test this time as seeking opinions on what is happening. If the idle jets are the problem why are they getting clogged up. There is an inline fuel filter (new) and one at the carb inlet (clean but blown out) so the clogging appears to be from something already in the carb.
Any suggestions?
Click to expand...

I had a similar issue where the carb kept getting clogged even after a thorough cleaning. The fuel filters (pre and post pump) were both completely clean so I was sure that the crud wasn't entering via the fuel supply. I looked for all the possible ingress sources (air leak, poorly fitting air filter, etc.) before I finally realised that the probable source was the crankcase breather that was venting directly into the carb. I inserted an inline catch can between the crankcase and the carb and no more problems! I obviously have some blowby that I need to deal with at some point and I can't say that this is the same issue that you are experiencing but it is worth considering.

See: https://xwebforums.com/forum/index.php?threads/crankcase-vent-hose.33012/#post-280821

Cheers,
Dom.
 
Cannot pump the fuel out. Bought a cheap electric pump (Facet copy) connected to tank outlet mounted below the bottom of tank and nothing came out. Unless someone knows different made a mistake with purchase. Now realise the X19 tank is different to most cars being in excess of 60 cm deep. So the pump I have will not lift that much. Read that electric pumps are pushers and not pullers and most have a dry lift ranging from 30 to 60 cm, so not enough.
Regarding crankcase breather very little gas comes out and on the last run forgot to connect back to air filter and still got the idling issue.
Need to find a way to get the fuel out, not wishing to remove the sender at this stage, too much risk with potentially rusted studs.
 
eng622 said:
Cannot pump the fuel out. Bought a cheap electric pump (Facet copy) connected to tank outlet mounted below the bottom of tank and nothing came out. Unless someone knows different made a mistake with purchase. Now realise the X19 tank is different to most cars being in excess of 60 cm deep. So the pump I have will not lift that much. Read that electric pumps are pushers and not pullers and most have a dry lift ranging from 30 to 60 cm, so not enough.
Regarding crankcase breather very little gas comes out and on the last run forgot to connect back to air filter and still got the idling issue.
Need to find a way to get the fuel out, not wishing to remove the sender at this stage, too much risk with potentially rusted studs.
Click to expand...
If you can get the rear of the car up a bit, it is pretty easy to remove the tank. There are two straps holding it in. Just disconnect the filler hose, and wires and hoses at the sender first. At some point you will want to remove the sender so you might want to put something on those rusty studs to facilitate removing the nuts. It is very hard to see much inside the tank without the sender removed.
 
eng622 said:
Cannot pump the fuel out. Bought a cheap electric pump (Facet copy) connected to tank outlet mounted below the bottom of tank and nothing came out. Unless someone knows different made a mistake with purchase. Now realise the X19 tank is different to most cars being in excess of 60 cm deep. So the pump I have will not lift that much. Read that electric pumps are pushers and not pullers and most have a dry lift ranging from 30 to 60 cm, so not enough.
Regarding crankcase breather very little gas comes out and on the last run forgot to connect back to air filter and still got the idling issue.
Need to find a way to get the fuel out, not wishing to remove the sender at this stage, too much risk with potentially rusted studs.
Click to expand...
 
eng622 said:
Cannot pump the fuel out.
Click to expand...
Well that's weird - I did a similar thing a few months back to remove some fuel that had stood for more time than it should. It was just a (very) old facet solid state pump as it happens and seemed to prime fine - the pump height didn't appear to be a problem. Have you tried the pump just on a can of fuel to test it out? see picture (don't try this at home kids!):

tank_pump.jpg


Have you looked at the state of the fuel sender studs yet? It could be they just need a wire brush and soak with plus gas or similar. The sender comes out ok (it's all relative I guess), but to remove the tank the rear of the car does need to be raised quite a bit and may tax the average trolley jack.
 
MikeHynes said:
Is the pickup blocked? Can you blow back through the hose? If not, I think you may have found the problem.
Click to expand...
Which then translates into getting the fuel sender out of the tank. It also may suggest a need to remove the tank if it is cruddy or it could just be the ‘filter sock’ on the end of the pickup.
 
Update. A replacement pump arrived. Fitted it higher up with the outlet inclined upwards and it pumped, so removed all petrol from tank. THere was nothing in the fuel I could see only as said before darker in colour than fresh fuel. Done two runs first 84 miles and no problem. Second run 110 miles and a stumble at 35 miles, quite bad and lasted for about 1 mile. Then it cleared and ran normal with perfect idle. I have fitted a washable glass in line filter and cannot see anything in it. So a big improvement but maybe there is some contamination in the fuel which can pass through the filter. As said in another post I filled up with E10 fuel.
 
eng622 said:
Update. A replacement pump arrived. Fitted it higher up with the outlet inclined upwards and it pumped, so removed all petrol from tank. THere was nothing in the fuel I could see only as said before darker in colour than fresh fuel. Done two runs first 84 miles and no problem. Second run 110 miles and a stumble at 35 miles, quite bad and lasted for about 1 mile. Then it cleared and ran normal with perfect idle. I have fitted a washable glass in line filter and cannot see anything in it. So a big improvement but maybe there is some contamination in the fuel which can pass through the filter. As said in another post I filled up with E10 fuel.
Click to expand...
Old gas is no longer proper gas. Many of the important hydrocarbons evaporate out and a result it doesn’t burn properly, thus why your car hasn’t been running properly.
 
kmead said:
Exactly what I meant, using the existing fuel outlet to the carb to get it out. You can get one of those siphon pumps (basically a sqeeze bulb with a simple one way valve to generate suction) to attach to the tank outlet.

Removing the sender is also easy, just lube the tiny threads first as you don’t want to snap anything off. The assembly is behind the plastic cover where the fuel lines come out.

It would be good to get a gander at the interior of the tank to see what is really in store for you. Just don’t use a match to look inside :)
Click to expand...
How does one easily ‘gander’ into a tank? Also, my local recommended always keeping an old tank full, true?
 
tvmaster said:
How does one easily ‘gander’ into a tank? Also, my local recommended always keeping an old tank full, true?
Click to expand...
By removing the fuel sender which lives at the top of the tank. Just don’t use a match to illuminate it.

Yes it is best to keep the tank full, particularly in a climate where there are good temperature swings with higher humidity.
 
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