Need suggestions. Broke down

Topic: Need suggestions. Broke down (Read 2015 times) previous topic - next topic

Need suggestions. Broke down

October 07, 2019, 07:19:57 pm

Need ideas. Drove 450 miles at 55 to 65 no problem. Turned off main highway to get to campground. Suddenly lost power. Saw small amounts of black smoke from exhaust and couldn't get over 45. Turned onto another road and was at 35 max. Limped into campground. I have gone to Napa and gotten a fuel filter. Will replace in the morning. I'm running out of daylight.

Any suggestions on what else to look for. I am in Clayton, NM so there isn't much here.

Larry

Re: Need suggestions. Broke down

Reply #1 – October 07, 2019, 07:31:03 pm

Larry,

You are doing the "first step" replacing both fuel filters.

Look carefully at the old ones to see if they look gnarly.

Re: Need suggestions. Broke down

Reply #2 – October 07, 2019, 08:07:34 pm

Betting 90% it's your fuel filters. What you are experiencing is typical fuel starvation. If you don't mind a wrap on the knuckles, have at least two sets of filters. You could have been stranded further away from a parts store and having a dead coach by the side of a busy freeway in a storm.

Don't install and try to fill them by cranking on the engine. Keep the secondary a turn or two loose and then fill both with the hand or electric pump until ALL the bubbles are gone. No pump? Then hand fill both filters before installing. Don't crank engine for more than 20 seconds or so. Wait a couple of minutes and try again.

Check see through on the bottom of the primary (if you have a see through bottom) after starting and every time you stop. You could have picked up algae that will clog the primary again.

Use a large plastic baggie on the filter when removing or bleeding the secondary when installing it. Keeps the mess down.

I have even pressurized the fuel tank with the outlet of a shop vac until all the bubbles were gone on the secondary filter and then tightened it.

Follow the instructions on the box that the filter came in or on the filter itself and don't over tighten it. Don't use ether on a warm engine.

Keep us updated.

Pierce

Re: Need suggestions. Broke down

Reply #3 – October 07, 2019, 09:12:51 pm

Thanks Brett and Pierce. I didn't get a secondary filter but called before they closed and can pick up in the morning.
The fuel in the clear bottom appears clear and green. When I remove it I will look for contamination.

Thanks for the reminder and suggestions.
Larry

Re: Need suggestions. Broke down

Reply #4 – October 07, 2019, 09:19:01 pm

Did you get any warning lights or alarms? Or was it just a slow down in speed?

Re: Need suggestions. Broke down

Reply #5 – October 07, 2019, 09:22:56 pm

If you change the filters and still get a slowing down issue it could be crap in your supply line caused by crud coming in from your fuel tank.
(don't ask me how I know 'cause I do know)

Re: Need suggestions. Broke down

Reply #6 – October 07, 2019, 09:40:51 pm

No warning. Slowed from hi way speed, made a left turn and no power. I will check fuel lines and ecm cables while down there.

Larry

Re: Need suggestions. Broke down

Reply #7 – October 07, 2019, 09:43:23 pm

Nitehawk, that is one of my worries that I got some bad fuel that ruined the tank. Still got 2/3 of tank.

Larry

Re: Need suggestions. Broke down

Reply #8 – October 07, 2019, 10:10:35 pm

It's not possible to ruin the tank. It may be just clogged over a period of time. Probably not much water in the tank or you would see it in the bottom of the primary filter. Good to purchase some biocide additive and keep using it for a while. It won't get rid of the algae but will kill it so it won't reproduce. Once the tank gets low, you can take a mirror and LED flashlight and take a look in the bottom of the tank. But only if your filler neck will allow you to see the tank bottom. Sometimes algae sticks to the side of the tank but mostly will be on the bottom.

Drive a diesel long enough and you will get algae or dirty fuel and clog a filter. No big deal. That's what the filters are for.

It still could be a lift pump or clogged line but a clogged filter is the usual suspect. We will see after you bleed the system and start it.

Change generator fuel filter also.

Pierce

Re: Need suggestions. Broke down

Reply #9 – October 07, 2019, 10:19:26 pm

First place to look it the pre-screen filter. You cannot see it on this setup without taking it all apart but it should trap tank sludge before it gets to the next filter. I do not know if this one is cleanable, hope so.

Diagnostics/history on your VMSpc too.

Re: Need suggestions. Broke down

Reply #10 – October 08, 2019, 10:04:39 am

How green is the fuel,that may be the problem,would do like the above and carry 2 or 3 sets after you fix this problem.
I'm not a believer of the "bad fuel" theroy,it's possible but everyone else would be broke down too,why just you?

Re: Need suggestions. Broke down

Reply #11 – October 08, 2019, 10:19:47 am

After thinking about it last night l am wondering if I could have possibly shook up gunk from the very rough road that I traveled on. I have about 2500 miles on this filter. As per talking with Roger, the first thing that I will do is pull the prefilled and check it. Letting the temp to come up to 45 degrees after breakfast to start checking it out.

Thanks for the suggestions.
Larry

Re: Need suggestions. Broke down

Reply #12 – October 08, 2019, 11:15:34 am

Quote from: John44 – October 08, 2019, 10:04:39 am

I'm not a believer of the "bad fuel" theroy,it's possible but everyone else would be broke down too,why just you?

Lots of diesel is green in color. Algae is black. All it takes is a little water in your tank plus a little algae from a fuel station. Everyone else does not get it because they are constantly using their trucks unlike most RVs with an off season and low mileage per year. An RV with a little algae in the tank will only grow more as time passes.

Cheap fuel in the U.S. means cheap roads and no fuel inspection. In this case, you get what you pay for.

To inspect an old filter, take a hacksaw and cut it so you can separate the top and bottom.

Low micron filters like the later diesels use will clog much faster than older coaches. I had to install extra Racor 2 micron filters on all the diesels I imported as the fuel here was terrible. The 2 micron filters would clog fairly fast and customers had to carry several cartridges in the glove compartment. I finally went to a Master Filter (brand name) as it was a larger square glass bowl with a lot more surface area and fit in the engine compartment easily.

Pierce

Re: Need suggestions. Broke down

Reply #13 – October 08, 2019, 11:32:45 am

I just got off the phone with technical assistance at Parker Racor. If you refer to reply number 9 from Rogers post that is the old style of 790r which has a pre-filter. Apparently I have a newer version which does not have the pre-filter the fuel is pumped directly into the 30 micron filter first then through the pump then on to the 10 micron filter on the engine. The way to tell the difference is with the new filter system there is a round cap with bolts on the very top of the assembly right behind the electric priming pump. The technical assistant said do not remove that priming pump since there is no filter there. Hopefully this will save someone in the future if they have the similar issue.

Larry

Re: Need suggestions. Broke down

Reply #14 – October 08, 2019, 12:11:55 pm

Don't overlook the fuel shut off solenoid. There is a spring in there that if it breaks or hangs up the fuel rack will not fully open and provides the same symptoms.

Re: Need suggestions. Broke down

Reply #15 – October 08, 2019, 01:24:39 pm

Quote from: Pierce & Gaylie Stewart – October 08, 2019, 11:15:34 am

To inspect an old filter, take a hacksaw and cut it so you can separate the top and bottom.

Pierce

If you want to avoid the debris left over from opening up a filter with a hacksaw, a Google search for "Filter cutter for inspection" will give you a more suitable tool. Every oil filter change on an aircraft, if you're careful, you inspect the oil filter for metal contamination.

FIT-1-G : Oil Filter Inspection Tool : GOODSON | Goodson Tools & Supplies

Filter cutter for inspection

Re: Need suggestions. Broke down

Reply #16 – October 08, 2019, 02:35:12 pm

Changed the filters and got the engine running. Drove around the campgrounds up to 20 mph, seemed okay. Got on the hi way and still short on power. Turned around after 1/2 mile and came bacwe are wto campground. The wife was following and said that there was steady black smoke. The vmspc didn't show any turbo boost. Can't say if the vms wasn't reading or no turbo. The VMS has been acting up the last 2 days and Roger is helping with this.

When engine has cooled I will check the turbo and the vacuum line to it.

Any other suggestions appreciated.

Thanks
Larry

Re: Need suggestions. Broke down

Reply #17 – October 08, 2019, 02:45:20 pm

Check all the turbo boot connections. Look good at the boots for one torn. If you are losing boost pressure you will have low power. CAC could be culprit also. " charge air cooler "

Re: Need suggestions. Broke down

Reply #18 – October 08, 2019, 02:50:50 pm

What to look for on the Cac?

Re: Need suggestions. Broke down

Reply #19 – October 08, 2019, 02:56:45 pm

On the CAC, look for any cracks particularly around inlet/outlet.

But, hoses/boots a more likely suspect.

Re: Need suggestions. Broke down

Reply #20 – October 08, 2019, 03:02:31 pm

If it is hose/boot, is there a temporary work around if new not available.

Re: Need suggestions. Broke down

Reply #21 – October 08, 2019, 03:13:13 pm

Larry,
Depends on what you find.

I have had the clamps break allowing a pretty massive loss of boost.

If a hose is split, not much option, as you are talking about some substantial PSI.

Re: Need suggestions. Broke down

Reply #22 – October 08, 2019, 03:20:10 pm

Thanks. Checking now but so far they look good. How can I check the turbo to see if it is free?

Re: Need suggestions. Broke down

Reply #23 – October 08, 2019, 03:54:45 pm

Duct tape .

Re: Need suggestions. Broke down

Reply #24 – October 08, 2019, 03:56:09 pm

You can check the turbo on the"cold" side, where air comes in by removing rubber boot and checking to see if the veins have damage or the veins free spool. I attached a cut out photo. But black smoke can also be a sign off too much fuel not enough air in the mixture. Perhaps a bad injector or pump depending on engine year/model. It does sound like a lack of air somewhere, either injector or escaping from air cooler or not creating enough boost.

Best bet might be to have mobile mechanic come out.

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