Ford 7.3 boost questions Lack of power (1998 E350)

[chasespeed]

Open the coolant res/ radiator.... if it smells like diesel.... injector cups. If not.... dont worry about it. If you do need them, send me a pm.... i have 6 or 7 still in the bags. Thay are a PITA w/o the tool.....

But, the filter and filter are before all that. Every time i changed my filter, it was black. I wouldnt worry too much.

Chase
Sent from my HTC Incredible

 

[Ozrockrat]

Open the coolant res/ radiator.... if it smells like diesel.... injector cups.

No abnormal smell there.

I did chase down a set of injector o-rings and the under cover harness's. Those will be going in tomorrow. I also did a check on the Injector Control Pressure. Reading are below. The top one is at idle and the bottom is WOT (Wide Open Throttle). ICP is a little low compared to some reading I have seen out on the web but it does not appear to be out of spec as far as my investigation show.

When it was hot I did do a couple of Cylinder Contribution Tests. They were inconclusive. Out of the 5 tests I got clear 3 times, #2 once and #6 once. If I had the time I would pull the injectors and sent them off to be tested but I need this thing going enough for the trip by Thursday. So I will give the o-rings and harness a try.

Now since the image is coming in so small I will outline what it is reading.

Top Row Engine RPM - Injector Control Pressure PSI - Injector Control Pressure Duty Cycle %
Middle Row Accelerator Pedal Position % - Exhaust Back Pressure PSI - Injector Control Pressure Volts
Bottom Row Engine Oil Temperature Input F - Volume Fuel Desired mm3 - Fuel Injector Pulse Width %

 

[Ozrockrat]

Replaced O-rings and wiring harnesses. PITA Test drive tomorrow.

Managed to replace the injector o-rings and the wiring harnesses. What a pain that setup is. Getting #3 out resulted in removing the solenoid. Now it is a little duller than the others under the buzz test but it does pass.

A couple of words of warning for others attempting this.

Find some way to either jack up the passengers side of the engine or lift the body off the chassis a bit. #3 is a real pain to get out otherwise and pulling the solenoid could cause "Maintenance Induced Failure" (i.e. fix it until its F@#$%d).

A good assortment of ratchets and various length sockets is very handy.

Don't leave one of the solenoid connectors off, especially on the 1-3-5-7 bank. (I will let you guess where that one came from).

Which leads to. Buzz test it before you button everything up.

Oil will get discharged out the exhaust. Don't go pulling the turbo to bits until you let it burn out / get pushed out. (again don't even ask where that came from)

If you are going to/ have wrapped your exhaust up-pipes/downpipe try to keep the oil off them.

Make sure your batteries are well charged before you go to start it again. It will crank forever.

 

[Ozrockrat]

AE health check readings.

OK just to keep it complete. Here are the readings and graph of the ICP, RPM etc. Taken after it failed again. Graph shows that the injector Control Pressure is within limits, Its calling for the fuel but it is not happening. Ran the cylinder contribution tests again when it had failed and they came back all clear even though it definitely had a miss on the highway.

I am being to suspect fuel supply problems. Next step is to pull the inlet side off the fuel pump, check for blockages there and also blow back through to the tank to see if the pickup or pipework is blocked or restricted.

That will have to wait until I get back from vacation. We are not going to Vancouver in this thing now. Looks like a week at a resort in Mexico instead.

At Idle

Wide Open Throttle

 

[TMiller]

bogging 7.3

I not really sure what is happening there with your motor but I can share an experience I had with my 98 e350 diesel.... I was losing power and it turned out to be the backpressure butterfly right after the turbo. It would idle fine but as soon as I tried to accellerate it would bog.

I drove the truck with the dog house removed and could see the butterfly would close every time I pressed the gas while driving. That system uses oil pressure and the valve thingy got stuck wide open which allowed full oil pressure all the time. The only time that butterfly should close is below a certain temp. (like 30 deg or something)

check your butterfly and report back......

 

[Ozrockrat]

Yep checked the butterfly and BPS early on when boost was the problem (1st problem).

I really should change the title of this thread. I think I have most of the boost loss issues sorted but I am still not getting sufficient power. But just as an update.

Drained and pulled the fuel tank. What a PITA its 55 gallons and had just over 12 gallons left in it. When I drained the fuel there was some rust and what looked like a few strings of chalking. When I removed the screen/pickup the screen had a bit of contamination but not too bad. But when I pulled the mixer unit apart the 2 screens in there were fairly blocked. (They filter from the inside outwards. That is all gunk from the inside pushing through the mesh)

Now the tank is at the radiator place getting cleaned and lined. I am removing the mixer and the in tank screens and replacing them with a screw on filter/water separator close to the tank. Eventually I will also put another lift pump and a 2uM filter up close to the pump. The photo below shows the pickup without the mixing chamber. I redirected the return to be as far from the pickup as I could (lots of baffles in the tank so I could not get it further away) and to push the diesel in a direction which will swirl around the curved baffle rather than splash around.

The idea is to move the screening/filtration away from inside the tank to somewhere it is field serviceable with parts available worldwide (probably CAT filters and a fuel pump the same as the existing one).

Hopefully that will happen tomorrow.

I not really sure what is happening there with your motor but I can share an experience I had with my 98 e350 diesel.... I was losing power and it turned out to be the backpressure butterfly right after the turbo. It would idle fine but as soon as I tried to accellerate it would bog.

I drove the truck with the dog house removed and could see the butterfly would close every time I pressed the gas while driving. That system uses oil pressure and the valve thingy got stuck wide open which allowed full oil pressure all the time. The only time that butterfly should close is below a certain temp. (like 30 deg or something)

check your butterfly and report back......

 

[Ozrockrat]

Looks like another problem solved. Yeeehaaa

Took it for a test run after putting in a small clear mesh filter just before the pump. Had to dump the diesel out of the on engine filter bowl a couple of times (using the water separator cable thingo). But I can now get to 80 MPH and cruise at 70. :smiley_drive::wings:

Test was cut short by not having any AC and it was 110 at least here today.:sunny::sunny:

But hopefully its first trip will be to LA monday to pickup a bike. And maybe it will even have the AC working by then :wings:

 

[Ozrockrat]

Hmmm maybe fixed. Ooops. OK I think its finished so the answer was fuel starvation!!!

Went for a longer run and it bogged down again. Drained the ford fuel filter and sucked out every bit of fluid. Not too much to write home about in there but I needed to check it out just to cross it off the list. (last filter change was a quick dump, pull, replace job).

So checked the small inline mesh filter and it was clogged. Replaced the mesh insert and headed up the hill. (dammed hard to find in Phoenix). Had to stop twice to clear/replace the filter element. There is still a lot of rust coming up the lines. (Luckily I had put wingnut style hose clamps on so it was an easy change).

Made it up the hill to sunset point with out any real worries. So coming back I decide to stop and pickup a bigger filter. Parked in some shade at O'Rielly's Autoparts and changed the filter. Cranked it over too long and either flattened the batteries or toasted the start. 1 1/2 hours later AAA arrived for a jump start. Their cables were not good enough so its on the tow truck and heading home.

The good news is that I got it home, replaced one of the 3 batteries and it fired up. Took it for another test run and it going very well. Now to fix the AC.

OK now the artsy crappy phone camera shot!

 

[addicted56]

I currently have the same issue in my F250. One of the tanks needs dropped and cleaned out. Hopefully I can get to it soon. That said hopefully you do the same. Kill the source at its roots and be done with this mess. It will end up leaving you on the trail when you least expect it.

Also check the fuel pressure regulator on the side of the fuel bowl. Ford uses a mesh wire filter in there and it can clog. I found out when I lost 2 fuel pumps in one week becuase I didn't know it exsisted. I just left it out completely. Also I can change the fuel pump out in 30 minutes and ford was going to charge me 7 hours labor. Hahaha. Glad you have it almost there. Thing is amazing.

 

[Ozrockrat]

Never knew they had a mesh screen in there

Also check the fuel pressure regulator on the side of the fuel bowl. Ford uses a mesh wire filter in there and it can clog. I found out when I lost 2 fuel pumps in one week becuase I didn't know it exsisted.

OK I never knew about this one. I do have the o-rings on order to replace to ones on the drain valve. Looks like I pull this filter as well (as soon as I get the CAT ones in line).

Thanks.:Wow1: