EnGINE

bigmike318 · Jan 22, 2010

Hello Anyone,
I am having trouble am I thought you could help. I am working with a freighliner fl 70 with a c7 cat. The idle is fine and runs well but then intermittent loss of power and smoke. 8,000 miles on engine. Never overheated. HELP!!

Thanks
Mike

piper1 · Jan 22, 2010

Welcome to the Forum....post truck questions in Truck Talk section (next one down) You will get more help there.

But...if you can answer these please, maybe I can help.

What colour of smoke?
Does the power loss happen going up hill/under heavy load?
If so does it happen right away or after you've been on it for a bit?
Does the sound of the turbo change when it starts to smoke and loose power?
Do you know what your boost pressure is (is there a gauge)?
If it's an fl70...and has 8000 miles on it, has this engine just been overhauled/replaced?

bigmike318 · Jan 23, 2010

it is bluish white smoke. No oil loss. No load at all. Its after about 10-15 minutes. I am just trying to see if its electrical. Sometimes it works excellent.

TeamCaffee · Jan 23, 2010

We had a problem similar to what you are saying but we had many more miles on our C7. The smoke was white and when it would happen there was a lot of it. We had it into several dealers before the Huey Pump finally failed and then they had to find the problem. The engine would still run but the truck did not have enough power to pull itself. I hope you can find the problem before you are towed.

piper1 · Jan 23, 2010

Have the fuel filters been replaced recently...maybe they should be.

Again I ask, you said it's in an FL70 (an older truck) yet the engine you said had 8000 miles on it. Is it new or does it have 800,000 miles on it?

If it is older, the HUEI Pump advice from Team C is very valid.

TeamCaffee · Jan 23, 2010

Piper1 we went through a lot of fuel filters before the problem was fixed. We had mechanics ride with us and not a single code was ever thrown. We were basically stuck with either changing parts or waiting for whatever to break.

piper1 · Jan 23, 2010

No codes....that makes things difficult theses days. What mileage did this happen to you guys?

TeamCaffee · Jan 23, 2010

The problem was finally fixed at 535,684.

RETIDEPXE · Jan 24, 2010

Ref; Huey pump. My '07 pre-emiss Cat C-9 i believe has a Huey. Met a gent at the Texarkana FL dlr who had just been towed in w/ a load knocking noise and the tech sd possibly the pump on his C-9 and that the trash from the pump also trashes the injectors. My truck, 364k mi.s, has began to have a light limp when setting in at a steady hwy speed around 14-1500 rpm. When i had pump the primer, it clears up for 10 mi.s or so then comes back. Replace the hand prime, helped some, but still slightly noticeable. Question; Are these pumps hard for a shade tree to replace. BTW, currently a set of injectors on ebay cheap.
Thanx,
Retidepxe

davekc · Jan 24, 2010

On a C9 it is not a job for the novice. Most of the time the failure is in the pump itself when the bearings start to fail. This causes a bunch of metal to run through the system. There was a service bulletin on the C9 in which they upgraded the pump.
Essentially the same pump, just a different bearing assembly.
After it is replaced, all the injectors have to be pulled, pressure tested and cleaned. Then the fuel rail tube has to be opened and a magnet test done to make sure there is no other metal debris. Failure to do this will result in injectors constantly going out as they pick up the metal and damage the injector tip.
Good luck on this as it can be a bit of a pain until it gets corrected. I would stay away from a truck dealer on this and go to a Cat dealer.

bigmike318 · Jan 26, 2010

It is an 05' Freight Liner fl70 with a C7 CAT

Runs excellent for the first 15 to 20 minutes then no power. Flat Accelarator. When you get reaction from acc. pedal, engine breaks up & smokes-all filters have been changed twice-engine not running hot...steady at 165. It shuts down for a couple hours & then ok again.

davekc · Jan 26, 2010

Temp sensor is throwing the ECM into protect mode. Check and r/r sensor and replace the thermostats. 165 op temp. is too low for a C7

RETIDEPXE · Jan 26, 2010

BigMike, you might check the fuel supply lines from the bottum of the tank/s to the fuel/water seperator if u haven't already. I'm not sure what kind of pick-up sock/filter is in the tank if any but may be running well long enough to stop up and starving for fuel, or lines collapsing??....I don't know, I once heard Kevin R. on XM say fuel lines can grow old and collapse and that Cats are especially sensitive to fuel starving issues. Be interesting to let us know what u find.
Dave, my slight stumble seemed to clear up w/ filter changes, think I picked up some bad fuel as there seemed to be more crap then usual in the fuel/water sep. But, your advice is warranted, I'm thinking if pump cratering is the norm on these motors, I might replace around 500K mi.s as a matter of preventive mntnce to avoid the additional fuel line/injector cleaning/testing involved.

Retidepxe

greg334 · Jan 26, 2010

How many of you drain your tanks on a regular basis to clean them out?

I never heard of fuel lines collapsing, I hear the filter on the tank doing that due to rust and garbage but not lines.

davekc · Jan 26, 2010

Could be at two seperate issues from two different members. Starvation of fuel or anything related has nothing to do with a operating temp of 165.

guido4475 · Jan 26, 2010

I'm in agreement with Dave.Also, they still may use the inline filter below the drivers seat area on the frame rail that is covered over by that black plastic wire loom.those rot out and clog also, because no one can see them, or even know that they are there.Caterpillar showed me mine.We eliminated it.this was on my 98 FL-70 with the 3126..

Deville · Jan 28, 2010

Guido, what does that filter do?

I have to look & see if I have one now, both of my fuel filters are located on the motor.

bluejaybee · Jan 28, 2010

It is just an inline fuel filter that you see on just about any vehicle. It is not the plastic see thru type. It is a metal one with threaded nipple on each end. Mine clogged the start of cold weather in Arkansas. I knew it was there, but didn't know that was my trouble at the time. $250.00 to replace it at Freightliner in Little Rock. I could move, but not very fast. Mine was full of gunk and water when they pulled it off. They are good for catching rust out of your tanks. But they do stop up. Mine was on a Sterling and it was pretty hard to get to.

guido4475 · Jan 29, 2010

It is called what International calls their's as a "Rock Catcher" . International has the similar setup, but it is closer to the main fuel filter,in a cap that unscrews with a screen inside. It is to catch the big stuff before entering the fuel filter, pump, etc.Not many paople even know about International;s Rock Catcher, even though you can see it plainly from the drivers side front tire.

Deville · Jan 30, 2010

bluejaybee said:
It is just an inline fuel filter that you see on just about any vehicle. It is not the plastic see thru type. It is a metal one with threaded nipple on each end. Mine clogged the start of cold weather in Arkansas. I knew it was there, but didn't know that was my trouble at the time. $250.00 to replace it at Freightliner in Little Rock. I could move, but not very fast. Mine was full of gunk and water when they pulled it off. They are good for catching rust out of your tanks. But they do stop up. Mine was on a Sterling and it was pretty hard to get to.

Did you have a water seperator filter on ur truck too? Cause I have a 2 filter setup, & for the most part when I change them they are always pretty clean. I have 2 get under the truck check it out.