Hey there, I've looked at the archives, but I'm still stumped. My car acted like the fuel filters were clogging, I changed them, it started fine, ran for about 2 minutes and crapped out. Started again and made it down the street. Died and needed a tow back up the block to my driveway.

When I try to prime the air bubble out of the lines (I can see the air bubble in the clear line immediately downstream from the primer pump) the primer just moves the bubble back and forth a little bit. I thought I'd replace that clear line. I also wonder if the fuel pump can fail in such a way as to prevent priming. How does the fuel pump/primer assembly actually work? I've got a spare fuel pump on my spare motor.

Oh, also, I checked the primer pump, it's of the new style and seems to function properly. I just don't know where it's pressure is going to... not into the secondary filter, that much is clear. Also, with the secondary filter unscrewed a little, the primer still won't push fuel through the line. I blew the fuel back up the line, made the primary filter clean, then used the primer would re-prime it... just a data point.

Thanks for reading!
Cheers,
Ash

__________________
Ash Peltier - tools, truck, tales
---------510-331-4118-----------
1982 240D - (272,000)
1998 Honda VTR1000F(RT) Superhawk Freeway (58,000) "Madrid"
1996 Toyota T100 4x4 (84,000) "Mary Kay"

I do not think it would hurt to get under the car at the back. Remove the jhose connection to verify you have good fuel flow from the tank before going on. The hand pump is just a pump to the best of my knowledge. Keep it simple at this stage. Another thing is to try to check the fuel line for a leak. You might be sucking air with your pump.

I agree, it sounds like the strainer in the fuel tank may be clogged, so the pump can't get any fuel. If you remove the fuel line from the first filter, upstream of the fuel pump, you should get a flow of fuel from the tank. Just to make sure, how muck fuel do you have in the tank? Sometimes clogged strainers become an issue when the tank is near empty.

Also, someone had a similar problem due to a plugged tank vent. Try it with the fuel cap removed to see if that's your problem.

Firstly, the air bubble in the clear line immediately upstream from the primer pump........in the primary filter........is normal.

If you have air downstream of the primer pump.........on the way to the secondary........this is not normal and the pump should force this air right into the secondary. If this is the situation, you're not getting any fuel to the primer pump due to a clogged tank strainer or vacuum in the tank due to a clogged vent, as Craig suggested.

First thing to do is to remove the fuel filler cap and try to start the vehicle.

Driad_98,


I had a problem some years back with my 240D on fuel starvation. Everything was fine until I got to the actual mechanical fuel pump that works off of a cam in the I/P. The cam pushes a piston & an internal spring returns it. Turns out that from running sumped jet fuel & not waiting long enough for the water to settle out somehow got to the pump & started to seize the piston where the spring was returning it intermittently. I limped the last 30 miles home at very low speeds making the slightest grades at a crawl. I rebuilt the pump & watched the quality of the fuel & no more problems. Although this has got to be a less than common fuel problem. Paul.

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1984 300CD red/blk 290,000 partial resto
1980 240D 4 sp Brn/palomino gone
1997 Mazda Miata STO edition wife's baby
1988 Lincoln Mark VII LSC next resto
1986 Subaru GL wagon daily
1993 Isuzu pickup field beater
2008 Honda Civic EX-L 5sp wife's new car
1978 Honda XL350
1974 Honda XL70 my Calif. ride in HS

driad,

Simple test: Remove the rubber fuel line that connects the inline filter to the steel fuel line at the rubber/steel connection. Get a small can of fuel and put the end of the rubber fuel line into the can and submerged in the fuel.

Pump the primer hand pump. If this primes you fuel system, the problem is somewhere between the end of the steel fuel line and the fuel tank and not the primer pump. This could be a plugged tank strainer, clogged tank vent or an air leak in the steel fuel line.

If this test doesn't prime the system, the hand primer pump is probably NG.

P E H

the fuel pump works on a cam set up . the cam drives the delivery valves and the lift pump, the whole pump operates at half the speed of the engine.. id show ya pics of one dissasembled but my cam is dead

Thanks for the ideas, guys. I'll let you know what I find out. The latest question that came to mind was about the feasibility of a failed fuel pump (piston seized?) could cause this... ok, ok, I've been running a mix of SVO and diesel, but I did check the strainer a short while back. It was totally clean. Also, the engine in my car came out of a car that flipped...

I'll do that test, PEH, thanks. Smart.
Cheers!

__________________
Ash Peltier - tools, truck, tales
---------510-331-4118-----------
1982 240D - (272,000)
1998 Honda VTR1000F(RT) Superhawk Freeway (58,000) "Madrid"
1996 Toyota T100 4x4 (84,000) "Mary Kay"

EVERYTHING I HAVE read shows that IF you are going to mix SVO/WVO, mix it with something thinner than diesel. also diesel tends to seperate/sublimate? when mixed into VO, that may be your problem itself... most here mix with Regular Gasoline (5-30%) or Kerosene (20-50%) along with other chemicals...
John