almost no acceleration

[Flanagan]

i was driving back home from a 3 hour highway drive and once i got off the highway and stop at the stop light off the exit, when i went to go again, i had to push the accelerator almost all the way down before anything happened, the acceleration was so slow and sluggish. my fuel gauge doesnt work so i use the odometer and its at 270 right now, do you think this sluggishness is due to the low fuel?

[Larry Delor]

Could be a dirty filter(s) too.

[Flanagan]

i know where the main and inline fuel filters are but ive never replaced them (its a new car, well new to me)......is there a trick to replace them because i dont want to take them off and then fuel start pouring out......what is the right procedure. thanks

Model and year?

[Larry Delor]

I'm gonna go out on a limb and guess its a 123.123 or a 123.133 ....

The prefilter is almost self explanatory....screwdriver is your main tool (unless you have new hoseclamps and want to use a nut driver)

Main filter is a spin on. There is a nut on top... if you loosen it, it will help you take off the filter. If memory serves correct..there is a copper washer that will want to be replaced.

After you are reasonably sure that you have replaced everything correctly, you ought to find the primer/hand pump, and prime the system until the bubbles are gone. Turn the knob on the pump counterclockwise until you are able to move the shaft up and down (as if it were a bicycle pump)


However....if my guess is wrong, I just wasted 2 minutes of my time that I will never get back, and it will all be your fault, and you should loose lots of sleep over it.

[Flanagan]

haha thanks, my car is a 1985 300D........so when replacing the filters, i dont have to worry about fuel spilling out?

[arcticathlon]

i just replaced the fuel filters on my new 1985 300D for the first time, and i had some fuel spillage. not much when i replaced the inline filter, but when i unscrewed the main fuel filter, it was full of DinoD and it spillled on the grass. (killing it, i looked today, all brown after 2 days) i was not sure how much priming i should do, i read until bubbles were gone, but it seemed like when i was pumping that there were air bubbles comming up and out of my IP. so i just kept pumping until i had diesel running down on the concrete adn there was a nice puddle. next time i dont think i will need to go to these extremes, but it was my first time, and i was nervous...

Originally Posted by arcticathlon

i just replaced the fuel filters on my new 1985 300D for the first time, and i had some fuel spillage. not much when i replaced the inline filter, but when i unscrewed the main fuel filter, it was full of DinoD and it spillled on the grass. (killing it, i looked today, all brown after 2 days) i was not sure how much priming i should do, i read until bubbles were gone, but it seemed like when i was pumping that there were air bubbles comming up and out of my IP. so i just kept pumping until i had diesel running down on the concrete adn there was a nice puddle. next time i dont think i will need to go to these extremes, but it was my first time, and i was nervous...

It's not an exact science, but you can prime with the main filter loose until it is full, then tighten it and prime some more. If you didn't prime enough, you'll know because it will not start. If that happens pump it some more (maybe 20 times) and try again. It will not hurt anything as long as you don't crank too long and toast your starter (no more than about 10-15 seconds is safe).

[Ara T.]

Originally Posted by arcticathlon

i just replaced the fuel filters on my new 1985 300D for the first time, and i had some fuel spillage. not much when i replaced the inline filter, but when i unscrewed the main fuel filter, it was full of DinoD and it spillled on the grass. (killing it, i looked today, all brown after 2 days) i was not sure how much priming i should do, i read until bubbles were gone, but it seemed like when i was pumping that there were air bubbles comming up and out of my IP. so i just kept pumping until i had diesel running down on the concrete adn there was a nice puddle. next time i dont think i will need to go to these extremes, but it was my first time, and i was nervous...

Yeah when I did my filters out on the side of the street I got some spillage and about 3 days later the diesel fuel ate through the top layer of asphalt, it just crumbled away

[H-townbenzoboy]

You may also want to check your throttle linkage adjustment just to be sure.
-Joe

[Brian Carlton]

I'm going to go out on a limb here and say that it's not fuel filters.

My argument is as follows:

You had the vehicle out on the highway at 3000 rpm or more and it was fine. The fuel flow was approximately 2.5 gallons per hour.

Then, you stop at a traffic light. The fuel flow drops to about .5 gallons per hour.

Now, it feels sluggish off the light. But, the fuel flow is significantly less than the fuel flow on the highway. So, if the filters were bad, the engine would have slowed on the highway.

I'll be curious to see if the filters help.

I will tell you, however, that the SDL did a similar thing when the fuel got down to the last two gallons. Significantly reduced power in all operations. Filling the tank didn't correct the problem until the vehicle was driven another 100 miles. Then, it cured itself and hasn't had a problem since.

Interesting.

Originally Posted by Brian Carlton

I'm going to go out on a limb here and say that it's not fuel filters.

My argument is as follows:

You had the vehicle out on the highway at 3000 rpm or more and it was fine. The fuel flow was approximately 2.5 gallons per hour.

Then, you stop at a traffic light. The fuel flow drops to about .5 gallons per hour.

Now, it feels sluggish off the light. But, the fuel flow is significantly less than the fuel flow on the highway. So, if the filters were bad, the engine would have slowed on the highway.

I'll be curious to see if the filters help.

Good points, but I suspect the engine also uses a fairly high fuel rate while it is accelerating from a stop. I have had a VERY clogged filter limit my top speed to about 50 mph. I still think replacing the filters is a good first step if you don't know when they've been previously changed. If the filters alone do not help, at least it will eliminate them from the equation.

Originally Posted by Brian Carlton

I will tell you, however, that the SDL did a similar thing when the fuel got down to the last two gallons. Significantly reduced power in all operations. Filling the tank didn't correct the problem until the vehicle was driven another 100 miles. Then, it cured itself and hasn't had a problem since.

Interesting.

That sounds like you clogged the screen in the fuel tank, and it took 100 miles for everything to shake loose again. I try to never get below 1/4 tank, who knows what's lurking in the bottom of these old tanks.

[Brian Carlton]

Originally Posted by Craig

Good points, but I suspect the engine also uses a fairly high fuel rate while it is accelerating from a stop. I have had a VERY clogged filter limit my top speed to about 50 mph. I still think replacing the filters is a good first step if you don't know when they've been previously changed. If the filters alone do not help, at least it will eliminate them from the equation.


That sounds like you clogged the screen in the fuel tank, and it took 100 miles for everything to shake loose again. I try to never get below 1/4 tank, who knows what's lurking in the bottom of these old tanks.

The fuel rate is not very high when coming off idle because the rpm's are too low. The rack won't allow all that much fuel. If he felt sluggish at 2000 rpm or above, I'd agree, but, right off idle there is no fuel restriction.

I agree that you have to replace the filters to rule them out. That's why I'm curious to see what the outcome will be.

I think the clogged screen is a definite possibility. I really wanted to change it when I did the two hoses, but, did not have the proper socket to get it loose.

Originally Posted by Brian Carlton

The fuel rate is not very high when coming off idle because the rpm's are too low. The rack won't allow all that much fuel. If he felt sluggish at 2000 rpm or above, I'd agree, but, right off idle there is no fuel restriction.

You're probably right, I just can't think of many things that could affect low rpm performance that suddenly. I would also take a good look at all the throttle linkage and make sure everything is in place. I had mine get all out of alignment because one of those little "c" clips fell off.

[Flanagan]

hey guys, i filled up the tank and shortly after, the sluggishness went away. its wierd. but ill still replace the fuel filters.