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TTS Newbie & 1st Diesel

Ray2377

New Member
Messages
29
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16
Location
Ohio
Hello all,
Firstly, I am not new to pickup trucks (on my 3rd & 4th), but am new to internet sites. I may make mistakes. I have an 02 F150 and just got a 97 K3500 diesel. Both are old, but comfortable like well worn boots. Both have a few issues, but are fixable (with help and knowledge). Thanks for being here!
 

Ray2377

New Member
Messages
29
Likes
16
Location
Ohio
Howdy again,
It’s uncanny how it’s been a year since I’ve had anything to say. Minor issues until now. Lost my 4wd and finally figured out a squirrel had destroyed the wire connector at the transfer case switch. Little bastard got my Nissan’s fuel pump connector too. So, over the summer it started backfiring/popping the exhaust when decelerating under load. This could be after acceleration at 55-65 mph, accelerating pulling a load, or coasting on a steep hill. My 71 year old mom says it has a “farting” problem (as it also puffs out dark smoke). When it slows back down to 30-40 mph it stops popping just like a switch got flipped. It did the same thing when I went to buy it and the guy fixed it, but I don’t know what he did. Vacuum is 20+ in Hg and boost pressure usually tops out at 9 psi. Any ideas?
But now, I can’t get it started at all. Last time it ran was mid October around 40 degrees and it took multiple tries over an hour to get it running. After started and warmed up, it started immediately every time the rest of the day. I parked it and the weather turned colder, averaging 35 degrees most days since. Batteries are a year old and I’ve charged them to 100% a few times, but I get nothing but gray smoke (it has always smoked on start up & usually idled rough for a short time the got smooth). I figured glow plugs, but the last time I tried it was 65 degrees. From what I’ve read, it could be a multitude of things, to include glow plugs, lift pump, air in line, IP, PDM ( which is on a heat sink already), etc. Again, any ideas to start ruling out some things?
Thanks
 

Will L.

Well-Known Member
Messages
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8,528
Location
Boulder City Nv
If plugging it in helps start it, then not enough heat is the issue, so look into glowplugs. I normally don’t like throwing in parts without verifying bad. But having recently bought it, new good plugs hurt nothing. Buy either AC Delco 60 G or Bosch 80034. Nothing else, period.
Remember to put a little antiseize on the threads when they go in.

If you loose the old ones coming out but they dont slide out easy, DONT FORCE THEM OUT. They can swell and will break off inside. If you have that problem, you can carefully screw it back in and buy the remover tool from Leroy. (He sells the good plugs too.)

Go to any hardware store and buy 6” long piece of 1/4” id clear tubing. Get 2 new screw style hose clamps for it. Replace the return fuel line coming off the front of your ip with the clear line. This is an upside down ‘U’ just behind thr oil fill spout. You will need to replace the clear line about every 3 years or so as it hardens and yellows, but it is cheap.

This is so you can always see fuel clarity when running and if there are bubbles flowing through it. Bubbles indicate air getting into the system and create wacky issues to running rough and even no start.

A fuel pressure gauge tapped at the ip inlet is the best upgrade to make to the fuel system. Being able to see your fuel pressure at speed could tell us if you are running out if fuel at the higher speeds- this sounds like a real possibility for your current issue.

If you have not yet replace the fuel filter, I suggest doing this at same time. Even if you don’t do that, drain some fuel from the drain fitting while idleing and examine how long it takes to get 1 pint. Then let the fuel settle for an hour and examine it for any contamination. However- if you open the drain and the engine tries to die stop and close it quicky. If the lift pump is not working opening that drain will suck in air and you may have to bleed the injectors.
 

Ray2377

New Member
Messages
29
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16
Location
Ohio
Thanks. That sounds like what I was thinking. I only get to work on it on weekends and when I have caught up on other chores. I will start with the glow plug removal. I will hose them with PB tomorrow and probably follow up next weekend again. I think I read somewhere that it’s good to spray diesel around them when loose to loosen up the carbon to make them easier to remove? The truck is old but only has 133K miles.
 

Jaryd

Love my 6.5
Messages
1,049
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1,439
Location
Hodges, SC
Spraying the glow plugs several times throughout the week with PB is a good idea.

With 133K it’s probably got the original injectors, harmonic balancer and crank pully on it. Seriously consider replacing those. Bosch injectors and
AC Delco balancer and crank pulley. All 3 are good for around 100K miles
 

WarWagon

Well it hits on 7 of 8...
Messages
8,810
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3,621
Location
AZ
You threw the Nissan in there and are confusing us. Backfiring out of the exhaust had better be the Nissan. Otherwise you got a hell of a banging noise that is completely unrelated to backfire or popping that diesels don't do. If it is you have bad valves, blown turbo, aka serious problems. A check of the transmission oil, transfer case oil, rear end, and front diff oil is in order. A busted gear can bang. So can a broken or locked up u-joint, bad driveshaft center bearing, Broken flex plate, bad harmonic damper - you need to inspect the harmonic damper every oil change. I am driving around with a banging noise is a warning something is about to bang one last time say before locking up giving you a fun ride with a locked up wheel - this is to make you re-consider the serious problem the noise means with a diesel. We are not there so your description is all we have and it sounds bad. Do not drive it till you know what this noise is.

As it won't start. Hold up a second. Before you blow $100-200 in parts without a clue as to what is wrong consider a shop diagnosis for the same amount of cash. Otherwise you need to troubleshoot the damn thing before removing perfectly good glow plugs and the time chasing your tail - with no results and a lighter wallet.

To start the engine needs 100 RPM minimum to start. This is Not a gas engine that will fire hardly turning over. Does it sound like it's cranking slow? Then, yes, it's turning over slow and WILL NOT START, PERIOD. Weak batteries, bad battery cables, bad positive connector, corroded cables, bad grounds, 1 of 4 brushes in the starter failed cutting RPM in half. I have an optical tach to check cranking RPM. If you shoot a video of it cranking (30 sec max or the starter starts to melt down) and post it on here, via youtube, we can tell by ear if it's spinning fast enough.

Air in fuel is the #1 thing to start with. No fuel No-start. Air in fuel compresses and no fuel gets pumped. Clear return line and lift pump test is in order.

Electrical - quick and dirty. Leave key off for a full min (or the results of test are random/bad as the ECM doesn't fully power off.). Turn the key to "run" for the bulb check. Do you get both the Service engine soon and the service throttle soon lights? Yes the ECM has power. No, no ECM power = no start.

Glow plug light? Glow plug light is powered of the glow plug harness so if the lamp is on the relay is good and you have power to the plugs. A resistance test of the glow plugs gives you an idea if they are possibly good. Open is dead, some resistance is maybe. I use an IR temp gun to test them. Take and record reading of head near glow plugs on cold engine. Cycle the glow plugs several times. Measure by the plugs again - any temp rise means the plugs are working. You could remove an injector and verify you got a glow or IR temp gun a hot tip. GM says use an clamp on amp meter...

If you plug the engine in overnight with a working block heater it should start without a working glow plug system. We did this a lot in Colorado as our 1988 6.2 ate plugs and controllers... What a difference the internet and modern troubleshooting make for the glow plug systems.

Do the above without buying parts and you can at least get an idea of what is working.

PMD failure including harness is the only part we throw at 6.5's after we verify the above. PMD failure isn't clear cut sometimes. We will get to the loosen injector line to see if it's pumping fuel at all later.
 

Ray2377

New Member
Messages
29
Likes
16
Location
Ohio
That’s a lot of info. First, The Nissan was separate. The popping noise is from the Chevy. It is not mechanical like u-joints or gears. It appears to be exhaust related. I will readdress that issue once again when I get it running. It seems like the starter is turning fast enough, but I guess that is subjective. It is parked too far from house to plug in, so I’ve got to work on it as is. I PB’d the drivers side glow plugs today, but couldn’t even see the passenger side ones. I didn’t know I would have to pull the engine to find them. I couldn’t find the glow plug relay either.
The glow plug/wait to start comes on solid, then slowly flashes over several seconds and then goes out. I tried to cycle this a few times prior to trying to start but it made no difference. I have debated tarping over the truck and using a kerosene heater to try and heat it up. I started an old JD crawler that way once in the middle of the winter.
As for the turbo, it built boost pressure the last time I drove it, so I assume it is still working. I have a new harmonic damper, but that’s a warm weather maintenance challenge.
 

WarWagon

Well it hits on 7 of 8...
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3,621
Location
AZ
Well and there is the fun of glow plugs you just noticed. My current project reminded me as I am staring at 7 Duraterm plugs and one 60G plug. Oh-Yeah! they don't match because the downpipe is in the way to change the #6 plug.

Have you ohm checked the plugs you can reach?

At this point ECM has power - glow plug relay is OK and Glow plugs at relay terminal are ok. Fusible links from there to the plugs are suspect...

It's possible with a cat converter... We call them soot traps for a reason. The banging noise may be melted down and broke up plugging up the works or muffler failure. Quick and dirty to check exhaust plugging is drop the crossover. You got the in person feel for the truck.

Is it spinning this fast for a subjective test? (Glow plug relay is gray thing driver side near firewall on the head. Well the thing the Ford starter solenoid is jumping on mine... Leave it alone as it's working!)

 

Ray2377

New Member
Messages
29
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16
Location
Ohio
I think the catalytic converter was removed and it’s just a straight pipe now. I can’t work on that problem until I get it running. I should be able to check for voltage at the glow plugs that I can see to rule out the fusable links? I have an optical tach, but what would I watch to determine proper rpm for starting? I have to charge up the batteries again, and it’s a whopping 19 degrees this morning.
 

JayTheCPA

Well-Known Member
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1,175
Location
Annapolis, MD
Checking glow plugs is done by resistance (not voltage). I forget what the correct Ohm's value range is and seem to recall that it is dependent on manufacturer. A reading of 0 (blown) or 1 (shorted / fouled ) are definitely bad. Or, just get a new set of GP's and GP controller if the budget allows.

Oh, and it was 19F here too :)
 
Messages
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Location
alaska
Yes on the voltage check to see if the fusible links are ok. If you have access to an ammeter the amperage on the entire glow system is supposed to be around 155 amps. IIRC
 

WarWagon

Well it hits on 7 of 8...
Messages
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3,621
Location
AZ
Have you tested the lift pump yet? Clear line on the IP return? Look the GM manual says check for air in the fuel system as step #1 for a reason. Water in fuel, gasoline contaminated fuel, fuel gelling with a bad FFM heater are all things step one looks at. It doesn't hurt to check the glow plug system out before winter hits, but, step one is air in fuel/working lift pump/fuel concerns.

Start here for lift pumps:
https://www.thetruckstop.us/forum/threads/lift-pumps-ops-operation-and-troubleshooting.6872/

After you are sure the lift pump is working: Loosen an injector line and see if it is dripping fuel. This can tell you a lot about what is or is not happening.

Finishing out glow plugs:

Check you got 12v to each plug you can reach. There is a fusible link to each bank of 4 plugs and a link to each plug. So 12v on any plug driver side means the bank fuse is ok. Same for passenger side. Of course this is best done with a clip on wire to check for voltage while the glow plug light is on. Light off means no voltage of course.

You want less than 2 ohms on each glow plug to pass the first test. Then literally pull an injector to see if the plugs are getting hot with help cycling the key. 2 ohms means the plug isn't burnt open, but, doesn't mean it's working.

Optical tach is on the crankshaft. I put the reflective sticker on the balancer and help spins the engine over till it reaches max crank RPM in a spin or two. The highest RPM number is what matters. 100 RPM is the min cold. How did it sound vs. the video above?
 
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