Volvo Forums - Volvo Enthusiasts Forum

Volvo Forums - Volvo Enthusiasts Forum (https://volvoforums.com/forum/)
-   Volvo 240, 740 & 940 (https://volvoforums.com/forum/volvo-240-740-940-12/)
-   -   New `87 Volvo 740 turbo - I have some questions (https://volvoforums.com/forum/volvo-240-740-940-12/new-%6087-volvo-740-turbo-i-have-some-questions-55323/)

pierce 07-05-2011 07:54 PM

could very well be the in-tank fule pump is failing or not working, so the external high pressure fuel pump has trouble gettin enough ga when the tank is below 1/2 or whatever

re: thhe valve cover gasket, much easier than the head gasket. failure just seeps oil outside the engine. if the oil leak is under the distributor, it could be the camshaft seal, thats seperate from the valve cover gasket, but also fairly easy to replace.

Typhoon 07-05-2011 08:02 PM


Originally Posted by pierce (Post 278275)
B230FT's ping like crazy on a warm day with the crappy regular we get around these parts, they just about have to have premium IMHO. a regular B230F, sure, regular is fine.

Which engine management system are you running? LH2.4 should never ping unless the knock sensor is not sending a signal, and then it'll just pull a lot of timing.

Koriflame 07-05-2011 09:34 PM


Originally Posted by pierce (Post 279567)
could very well be the in-tank fule pump is failing or not working, so the external high pressure fuel pump has trouble gettin enough ga when the tank is below 1/2 or whatever

re: thhe valve cover gasket, much easier than the head gasket. failure just seeps oil outside the engine. if the oil leak is under the distributor, it could be the camshaft seal, thats seperate from the valve cover gasket, but also fairly easy to replace.

Thanks, I'll order one of both since they are so cheap.
That would be this one? Volvo 740 Turbo Camshaft Seal- Engine Parts- Volvo Parts

And is there a way to test the in tank pump without a volvo pressure gauge? I was planning on pulling out the entire in-tank assembly to see if there is any repairable damage to it from his presumably shotty installation.

pierce 07-05-2011 09:45 PM

thats probably the part but I'm feeling remarkably unmotivated to look up part numbers and such right now.

re: the fuel pump, you could disconnect the line from the tank pump to the main pump, aim it into a clean fuel can, and manually power the pump (can be done with a jumper at the relay panel, see the various 7xx FAQ's for suggestions). if the pump is working, a steady stream of fuel should come out. of course, exert all cautions around fuel vapors and sparks!!

you can do the same with the fuel return line that comes out the back of the fuel pressure regulator, disconnect it there, connect a length of fuel hose into a fuel can, run the pump manually for, say, 8 seconds, then measure how much fuel you get, the main+tank pumps together, through a working regulator, should be outputting about 1 gallon/minute, so 8 seconds is about 1/8th gallon or one pint. note that 1 G/min is very approximate, anything from half to twice that is acceptable.

again. be very very careful around fuel with sparks!!!

Koriflame 07-17-2011 05:20 PM

I've been putting off pulling the sending unit out to check things, but would it be a possibility that the unit is in there crooked or upside down? I plan to pull it out when I run the fuel down a little this run.

I could post a picture of the position of the cap of the sending unit if anyone is willing to compare to theirs.

Koriflame 07-25-2011 11:56 PM

Okay finally got ahold of a multimeter. I checked those fuel pump wires
Pink: 12.9v
Brown: 12.9v
Gray: 6.79v
Ground: 7.12v

Is that normal? I'm thinking gray should be 12.9 as well and ground shouldn't get that much if any. I'm not a professional by any means... just checking around before I get help pulling the intank pump.

Also arent the pumps supposed to engage in kp2?
Turn key to position 2 -> Nothing
repeat -> Nothing
repeat -> Nothing
repeat -> Nothing
crank to pos 3 -> Nothing
crank to pos 3 -> relay ticks on, fuel pump is audible -> Car starts

My relay is dated 7-13-2002, It would be fantastic if that's all it is, but I kind of doubt it since the fuel gauge is involved. I could live without knowing how much gas it has if the cost to repair would be $320 for a new assembly.

pierce 07-26-2011 12:24 AM

when you switch the key on, the pumps should run about 1 second to build some fuel pressure but then shut off. then when the engine turns around, the RPM sensor picks that up, and the fuel pumps come back on. actually, your 87 is a LH2.2, it might use a different rotation sensor than the RPM sensor of the LH2.4 cars, I'm not 100% sure, but still, when the engine turns, the fuel pumps come on.

where did you check tehse fuel pump wires, was this back at the gas tank, or the main pump under the car? ground (which should be black) should be 0V relative to any clean chassis ground. my schematics say the pump power wire is pink at each pump, and yes, that should be + battery voltage, which is around 13V when fully charged. the gray and brown wire is probably the fuel gauge.

there's a bunch fo simple tests at your relay panel you can do to test fuel pump operation... see
Engine: Fuel Injection

Koriflame 07-26-2011 12:49 AM

This was back at the in tank at those odd connections in the trunk yes. (This is while the car was running)

pierce 07-26-2011 01:15 AM

here's the in tank pump and sender parts breakdown for a 87+ 740 w/ the B230FT (turbo) engine...

https://lh5.googleusercontent.com/-i...6%252520PM.jpg
click for larger


All times are GMT -5. The time now is 06:53 PM.


© 2024 MH Sub I, LLC dba Internet Brands