Terrible MPG after new IP install,

[matt-jenkins]

I've got about 1000km on my new IP and ever since I have been getting worse fuel mileage then I was with the old worn out pump. I changed my fuel filter the same day the pump was installed, I lined up the timing marks on the pump and gear cover when I installed the pump. I however have read that these timing marks do not mean anything when pumps have been changed. No shop locally has a timing meter, Would retarding the timing potentially help my mileage? I am currently getting 9-11mpg city driving, I Have never seen more then 14-15 on the highway ever.

 

[LCAM-01XA]

retarding it may help, but so may advancing it - all depends on in which direction it's off now. When you fire up the truck cold, do you get smoke out the pipe and if yes what color is it. Then once warmed up, can you still smell a strong diesel smell in the exhausts while truck's idiling, even if no smoke is visible?

 

[IHDiesel445]

If the engine sounds unusually quiet, your timing may be retarded too much. Likewise, if your timing is advanced too much it will be much louder than you remember. I'm talking about the "diesel knock" sound, not the exhaust note. Advancing the timing makes the knock sharper and louder, retarding makes it sound more muffled and quiet.

Like you, I couldn't find anyone with a timing meter last time I replaced a pump. I just set mine using the seat-of-the-pants-o-meter. The spot where you get the most power and acceleration response is where I got my best mileage too. Properly timed, you should be pushing 20 mpg on the highway.

Hope this helps!

Eric

 

[Agnem]

Typically when the marks are aligned, the pump is actually pretty retarded. You really should get it dynamically timed, but I would imagine up where you live it may be hard to find someone with a meter. Try moving the top of the pump towards the passenger side about 1/8" (I have no idea what that is in metric sorry).

 

[nsjames]

(I have no idea what that is in metric sorry).

lol

1/8" is about 3 MM.

 

[damac]

I am no techy are all these old idi engines similar when it comes to advancing and retarding?

On my old vw I time my pump by ear while the car is running. I will warm the car up and take it for a drive then come back and park it and leave it running. Then I adjust the pump so its on the verge of cackling, but not that hammer like nailing noise.

At this point there is no white smoke, but if it was a tad bit retarded it would put out a steady white puff of smoke. There is a fine line once in the ballpark, like just nudges of the pump.

My pump also has a manual cold start lever so I leave that alone when I come back for a drive. Then if it gets cold I will start the car up and pull that lever and it makes the engine a bit noiser while warming up, but the car idles smoother. Drive off and 5 minutes later push it back in.

So on mine advancing it gets better mileage, but you don't go so far that it puts holes in your pistons. Also if you advance it to far, it makes the car harder to start as in the starter will struggle to turn over.

I will be doing the same thing with our clunker soon and I don't want to pay to time it

 

[Agnem]

lol

1/8" is about 3 MM.

I'm a product of the Jimmy Carter era of public schooling, so we were taught the metric system, but then quickly told to forget about it.

 

[matt-jenkins]

Thats OK Mel I was born and raised in Warrenton Virginia, I still use the good old standard system.

On start up I get a puff of grey, when it was really cold after the pump swap I would blow solid grey for the first 200 yards of driving after leaving the driveway. No strong diesel smell when Idling. I went to try and pick up an offset wrench today to fiddle with the pump but the local retailer was sold out. Maybe sunday I'll advance it a hair and see what that does.

 

[FORDF250HDXLT]

how many miles do you have on your injectors?

 

[NJGearhead666]

I'm a product of the Jimmy Carter era of public schooling, so we were taught the metric system, but then quickly told to forget about it.

Thank God for Regan lol

 

[matt-jenkins]

how many miles do you have on your injectors?

For all I know they could be the original set, I will try slightly advancing the pump on sunday when I track down a wrench to loosen off my pump bolts. even with the cold advance/fipl taken off I cant reach the bottom two.

 

[FORDF250HDXLT]

i would start there.
i was surprised how bad my stock '93 E codes looked.
many leaking tips.having a nice strong supply of fuel now,but feeding worn out injectors is likely a bad combo for fuel economy.

 

[Diesel JD]

Hey Matt, somewhere on the forum is a thread by Gus(biofarmer93) that tells you how to take a standard 9/16" box wrench, torch it and make it an IP obstruction wrench. I haven't tried it but I know he does his homework before he does something like that. Looks like it would work well, cheap as long as you can find an el cheapo China wrench and have a grinder and torch, vise, piece of pipe to bend it with. It's on the short to do list, but time and money are kinda tight.

 

[Diesel JD]

Just wanted to say +1 on those injectors, if they are that old they probably are worn out. If nothing else, worn injectors and a new pump or worn pump and new injectors definitely changes the timing. Not advocating outright replacement just saying you should test them if you can.

 

[matt-jenkins]

I got a standard moon wrench to fit when I did the pump install, Im just going to buy one of those and grind the ends down for a few mm of clearance. I hope and pray every time that I tighten those bolts I will never have to touch them again so I dont want to make a wrench.