|
|
|
So, I've not been having very good luck lately. 1980 GT with B21/K-jet. To explain a little of what has been going on. When the tank is full with fuel it runs good (I still think it's low on power). Once I get to about the half way mark on the gauge I start having issues. It's as if I'm out of gas. I know this isn't the case as I'll go to fill it up and it'll only takes 5 or so gallons. So, I've pulled the intake pump. I checked the rubber hose and that seems to be in good order. Also verified that the pump is working. It seems to be working just fine. This is a replacement pump from the junk yard as the pump that came out was toast. Just last week I did replace the filter on the pump as it was pretty dirty. Once the car is down to about a half tank of gas the inline pump will start making noise as though it is struggling for fuel.
Now, for the strange part. When down to about half a tank and the car runs as though it's not getting enough fuel, I can park it for a while and than start it up. It'll run fine for a while before starting to act up again. I don't want to just throw parts at this as gas alone is breaking the bank. Could the in tank pump just be weak and not pumping enough fuel once it's a little low on fuel and possible heating up? Could the inline pump be not working correctly? It all seems odd to me since when I let it sit for a while it will than run okay.
Also, the car seems underpowered (used to my 1986 B230 so may not actually be) and getting horrible fuel economy (15mpg). I thought I would add this in as I'm not sure if it will be helpful. Oh, one more thing. I don't have one of them fancy fuel pressure gauges but, I did check pressure at the filter under the hood and I'm sitting right around 120PSI.
Sorry this is so long, I'm just really getting frutrated and need to get this car fixed!
|
|
-
|
|
|
You have described all the symptoms. The main pump - which you refer to as the inline pump, makes noise, which is cavitation, below one half tank of fuel. The purpose of the in-tank pump is to transfer fuel to the main pump, which allowed Volvo to use top fittings on the tank. When the fuel level in the tank gets low, and the in tank pump has failed, the main pump cavitates, and that causes low fuel pressure, and as you say the engine seems to be running out of fuel. It is.
Install a new in-tank pump. It should be an easy task, as you've had the assembly out a few times already.
|
|
-
|
|
|
I'm thinking I may just replace the pump, hose, etc. Thinking though, can the tank pump still work and just not be enough? From my experience a pump usually works or doesn't. The tank pump seems to be working just fine.
|
|
-
|
|
I don't have experience with a "weak" in-tank pump, but do have experience with one being fed electricity backward. Not saying that's your trouble, as you didn't mention any replacement or mods to the sender assembly, but like Rhys said, the purpose of the tank pump is to keep fuel under slight pressure, about 5 psig, to feed the main pump with liquid, not vapor. When the main pump cavitates and that corresponds to 1/2 tank of fuel, there's no other explanation than the tank pump isn't doing its job, even though a worn main pump will depend more on a good tank pump than one that's in good shape. Of course, you said the previous tank pump was defective, and that's what wears the main pump.
The 120 psi test doesn't really tell you anything, without taking into account pressure rise time and feed conditions. Of course, the wiring between fuse 7 and the relay, and then to the main pump needs to be free of contact resistance.
In The Tank
--
Art Benstein near Baltimore
Police were called to a day care where a three-year-old was resisting a rest.
|
|
-
|
|
|
So, I just finished changing the in tank pump. Installed a Carter pump P74067. It was listed for a 1988-1990 Volvo 740. I pulled an Airtex pump out of it. It was working and pumping in the correct direction. After changing the pump, it does seem the main pump is running quiter as well as no more cavitation. I will see how it does here in a few driving to work. My local parts store didn't have a pump available for any year 240 model. Not sure what the difference between the 740 and 240 of these years but, it fit, mostly. It was a tight squeeze installing it onto the sending unit.
|
|
-
|
|
|
Thanks for writing back, and let us know how it runs in a few days.
|
|
-
|
|
|
It ran great (still thinking under powered) for about 30 minutes. Than, it ran out of what power it does have. After turning it off for 10 seconds or so it would run fine again. Did this a few times bringing it back home. Fuel filter and brake pads to be done here shortly. Will let you all know if changing the filter helps or fixes the problem.
|
|
-
posted by
someone claiming to be CB
on
Tue Apr 10 16:06 CST 2012 [ RELATED]
|
|
You want to have this
Volvo Probem Solver Advanced Edition (out of print) 242pgs
https://files.me.com/dustinl.c/le9rdc
|
|
-
|
|
|
Tried to open this. Was told "File is damaged and can not be opened."
|
|
-
posted by
someone claiming to be CB
on
Tue Apr 10 16:24 CST 2012 [ RELATED]
|
|
try it directly from the post
http://forums.turbobricks.com/showpost.php?s=4e8ef2d1667e0f9d227cd79b32fe3091&p=3296397&postcount=8
|
|
-
|
|
|
Hi Art,
As a new grandfather I particularly like your latest pun! Good one!
Rhys
|
|
-
posted by
someone claiming to be CB
on
Fri Apr 6 16:42 CST 2012 [ RELATED]
|
|
"Also, the car seems underpowered (used to my 1986 B230 so may not actually be) and getting horrible fuel economy (15mpg). "
+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
I've got an 80DL (not turbo-GT). At the worst I get low 20's mpg and that's in heavy jammed traffic.
A GT should actually be "peppier" than a straight B230
Suggest that there is something else going on here, beyond the in-tank pump.
|
|
-
|
|
|
The "GT" is a B21F motor. The American version did not have anything special under the hood. Other than maybe the higher 9.3:1 Compression. I've checked timing (ignition and cam) and, all seems well.
Now, about 2 months ago I took a 40 mile trip at 75mph and the car did great! On the way back home, I struggled to do 60mph. Something for sure is going on.....frustrating!
|
|
-
posted by
someone claiming to be CB
on
Fri Apr 6 20:58 CST 2012 [ RELATED]
|
|
Missed that GT...I believe in later years it meant Turbo.
Going from your other response about the history...\ in the barn and your repairs on the car.
Have you checked the connections for corrosion on the Main fuel pump, both at the pump itself under the car....Push on connectors which should be protected by boots... and the ground, which is located inside the car, underneath the rear seat drivers side.
I changed out the main fuel pump on my 80 and found the connectors... under the boots... were shot, had to splice new ones to install the new pump.
(You said you had corrosion in the FI Relay...that's pretty much a protected device...inside and with a plastic cover)
|
|
-
|
|
|
Could the fuel relay cause this? Just checked mine. It's fairly hot! And, a diode of some sort is broken off when I opened it up to check it. It also has lots of rust type corrosion on it. I cleaned it up and re soldered the diode back on. Does seem to have more pep now. Could be a placibo effect though.......
|
|
-
|
|
|
I like the debris in the tank idea. It makes sense. I had the same problem with my 122.
Is it possible that the tank isn't venting properly? When the car starts presenting the symptoms you describe, can you remedy them by opening the gas cap allowing air into the tank accompanied by a whooshing sound?
My bet would be on crud in the tank, though.
Good luck! Let us know how things turn out.
--
1966 122s, 1968 142s, 1969 144s, 1979 245dl, 1989 244gl
|
|
-
|
|
|
Now, this makes sense, I think. The tank not venting.....However, full or empty, I'm not ale to grasp how this would stop the pump from pumping. If anything wouldn't it just collapse the return hose or the "emissions" hose? I'm not sure on this one. The crud in the tank part has been addressed. New Filter, New pump strainer, good hose, verified pump is working (Of course I can't tell if it's working when the car acts up), etc......I may just say heck with it and replace the in tank pump. I've heard the Delco's are the best? What about the Carter pumps? That's all I've ever used on my old Chevy's. Carter or OEM Delco.
|
|
-
|
|
|
re: "...Once the car is down to about a half tank of gas the inline pump will start making noise as though it is struggling for fuel....
... Could the in tank pump just be weak and not pumping enough fuel once it's a little low on fuel and possible heating up?....
...I did check pressure at the filter under the hood and I'm sitting right around 120PSI. ..."
The in-tank pump isn't heating up (besides that it's immersed in the fuel to keep it cool).
There's a little hose, about 2 inches long, between the in-tank pump and the metal fuel line on the fuel level sender assembly (look at a diagram of that assembly to see it). On a 1980, it's an almost certain bet that by now the hose has split or cracked a leak -- they don't last forever, you know.
Now here how it fits the symptoms. When the tank's fuel level is above the hose, the submerged hose only sucks (Bernouli effect) more liquid gas into the stream, and so everything is good -- nothing but liquid fuel going to the main pump. But when the fuel level is below the hose, fuel vapor (I'd rather not call it air, inside the tank ;-) is sucked through the hose's leak and you've got a lot of bubbles, instead of pure liquid fuel, sent on to the main fuel pump -- so that pump is now starving, and can't keep up with the engine's consumption of fuel, so your engine feels weak or even worse, especially under load.
Now, the pressure you measured, 120 psi, is a measurement with the engine idling (I hope you weren't driving the car at the time :-). Then, the engine needs little fuel, and so the main pump could deliver at full pressure despite the foamy fuel it's being fed. But (a big "but") when you're actually driving so that the engine is under load and is craving more fuel, I'll bet your pump can't deliver that same pressure -- now the effects of fuel starvation shows.
Sounds like it makes sense to you?
You have to pull the sender assembly and (at the very least) replace that short hose; with your car's age, though, I'd think about also replacing the in-tank pump and sock (since you've already gone to the trouble of pulling the whole thing out of the tank).
Good luck.
|
|
-
|
|
|
Thank you for your advice. I did replace and verify the little hose was in good order! Before I bothered to even post I verified that. This is why I'm stumped. In my original post, I believe I even stated I pulled it out and, checked it. No cracks, no holes, etc. Held pressure from me blowing into it while clogged as well as about 5psi from my compressor. Also, a new filter strainer was installed a few days ago due to the old one looking fairly bad. Changing this helped none the same.
|
|
-
|
|
"When down to about half a tank and the car runs as though it's not getting enough fuel, I can park it for a while and than start it up. It'll run fine for a while before starting to act up again."
Is this car just coming back to life after setting for years? I ask because it could be rusty tank crud choking of the tank pump till it stalls (or you give it a rest). At rest, the crud drops off the filter sock enough so you can go again, till he next time.
At least that was my experience with an old 140 that had a terribly rusty tank, which I had to replace. It would idle all day in the driveway, but on the road I could see the fuel pressure drop as it clogged up. Rest and go...rest and go...etc.
That 120psi must mean a good main pump, but it's the regulated pressures (Control and System) that count. That's where the "fancy gauge" pays it's way.
--
Bruce Young, '93 940-NA (current), 240s (one V8), 140s, 122s, since '63.
|
|
-
|
|
|
Hi Bruce.
Maybe he's got a combination of two problems. I'm betting at least on the little hose, because of what he says about the fuel level being a factor (viz., good when the tank is over one-half, bad when the tank is below one-half) -- although my personal experience is more like above and below 1/3 tank.
But your idea of the crud clogging the sock is also good (viz., it recovers after sitting a while). I had a brand new 164 back in 1973, and it developed a problem only about a couple of months after purchase -- the car would stall out abruptly, and then only after a couple of minutes could be easily restarted. The regional or zone rep was called eventually, and he discovered a faulty fuel tank filter that was collapsing (the car didn't have the in-tank pump and sock of the 240s, but the idea is the same). I can imagine the crud collecting on the sock and choking it off, but it can't explain the effect of fuel level -- the same amount of crud should be there whether the fuel level is high or low.
So maybe the problem is two-fold, the crud and the hose?
|
|
-
|
|
|
I did replace the filter sock a few days ago. This is when I verified that the rubber hose is in good order. Now, that being said, the sock was very dirty. I replaced with a new one to no avail. Still having the same problem. The car, about 2 years ago, did come back from the dead, than sat another year and am now using it more often.
Originally the tank pump was seized. I replaced it with a known good pump (however, old). I just don't want to put a new pump in if that may not be the actual problem. If I do replace it, I've read somewhere about a pump from a different Volvo, 740 maybe, that had a higher flow rate or pressure. Is this true and if so, what might I ask for at the parts counter?
Thank you all so much for your help. I am very familiar with old Volvo's. Just not so much so with the K-Jet system.
|
|
-
|
|
|
The higher capacity pump about which you commented is a known upgrade for older 240s (I think those prior to the B230, but maybe for all 240s) -- it's discussed at length at IPDs website, which offers such an upgrade kit (in addition to the normal replacement kit).
However, you should note that doing the upgrade requires some work, including precisely cutting (shortening) the metal fuel line (because the upgrade pump is longer), and fabricating a new clamp (the old one doesn't fit).
Just a thought, though: I can't believe that you didn't replace the hose, having gone through the trouble of accessing it, because it's a well-known problem, not to mention that this piece of rubber has now spent 32 years immersed in gasoline, at least some of that time while containing powerful solvents (e.g., ethanol, and before that even more awful MBTE which I'm sure was the cause of my own '80 245's hose breakdown). I wouldn't have trusted the check you did -- no offense intended, but it's just that there may have been some separation that you may have missed, given that the symptoms you described fit a failed hose so closely, and that piece of hose is so inexpensive.
|
|
-
|
|
|
It actually is a new hose from 2 years ago when I bought the car. Before that it had sat in a barn for 15 years. So, at that time new hoses where installed. It was stored fairly well and so, not too much needed to be done but, almost all rubber was replaced (hoses, belts, door trim, etc). All the injectors were cleaned, the fuel distributor was cleaned, filters changed, oil changed twice, head gasket replaced, all seals and gaskets replaced, thermostat, water pump and, I'm sure much more I'm now forgetting.
Other than what seems to me as a lack of power and this fueling problem it runs well. I can drive it all day in heat, traffic, etc. and have no problems as long as I keep it above a half tank.
The Fuel relay has now been found to be an issue from what I can tell as I posted in another response and the main pump has not been changed but, it seems to be fine.
|
|
-
|
|
|
There is a rubber hose on the in-tank pump that eventually rots and causes the symptoms you describe. Remove the fuel gauge sender and replace the hose. It is best to get the correct replacement hose but you can substitute fuel line rated for immersion in gas.
Dan
|
|
-
|
|
|
Rubber hose is in good order. I even removed it, closed off one end, and blew into the hose and no air leaked out (gas tastes horrible). Checked it for cracks, etc. Retightened hose clamps and all.
|
|
|
|
|
