Second opinion on my loss of power diagnosis please!

[btmurph]

So a few weeks ago my 1009 started losing power. It would start and run fine in the morning but by the time the engine was fully warmed up the idle was down and I couldn't maintain speed going uphill (would slow to 45-50 from 65). It got to the point after a day or so that when I needed to stop I'd pop the tranny into neutral because the idle was so low I was afraid the truck would stall. I replaced the fuel filter, reprimed and everything returned to normal. When I drained the filter there was definitely some gunk that was caught. A week later the same thing happened so once I got to work I swapped the filter again... same issue, didn't fix the problem. I apparently wasn't thinking straight because the next day I swapped the fuel filter again but it's still doing the same thing.

It appears that when the engine is cold it starts and runs fine (although the last day I drove it the idle sounded "off") but after the engine is fully warmed up there's no power and the idle is very low when in gear.

My diagnosis: My IP is bad and needs to be replaced. Does this sound right to everyone? I searched the forum but I never found symptoms exactly like mine. My lift pump is functioning fine. My only other thought is I needed to drop the tank and clean/replace the fuel sock (which I'll do soon anyway) but the fact that it runs fine after sitting for a while but loses power when the engine is warm leads me to the IP.

Thanks in advance folks!

 

[welpro222]

Bypass fuel tank test: Disconnect fuel line that goes from tank to filter, add a line from filter to fresh diesel in a fuel can, reprime system and see how engine runs when it warms up. You do a road test if you have the can in the cab and enough line to reach the filter.

This will at least rule out the tank.

 

[cucvrus]

My vote if it matters is the injection pump. But if you go that route drop the tank and change the fuel sock first. I would recommend everyone change that fuel sock that has never changed them. I posted pictures here they look bad at this point if they have never been changed. It is an AC Delco item at Autozone it is like $30. US.Hey I hope that helps. I have had good luck with Diesel Care rebuilt pumps in Memphis TN. I hope you get back up and running again.

 

[rsh4364]

Sound advice from welpro,but I would think IP pump rebuild seeing how it starts well when cold.And only has problems when warm/hot.Have you tried the cold water dumped on IP when warm/hot?To see if it starts better,if it starts better, would suggest bad rotor in IP.

 

[welpro222]

I was gonna say the Injector Pump too, but I just couldn't be the one to deliver the bad news.

 

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You might want to rule out air getting into your fuel from some intermittent leak that opens up when warm. If that's the problem, it's cheaper to fix than an IP, and a new IP won't fix the problem.

 

[Chaski]

The water on the pump diagnostic trick will let you know if your head and rotor are junk or not. The bad thing about that method is that if your head and rotor are good, and you toss cold water on it when hot a possibility that the head will shrink around the rotor and sieze. The head and rotor assembly is a pile of cash. If you plan on having the rig for a while you can get a pump with new head and rotor, and a sleeved advanced piston bore off eBay for less than $780. That being said be cautious about who you have rebuild your pump, or who you buy one from. I had a guy do a beautiful job on one, he sleeved the advance bore, ran great... Until the seals in it went bad. I have no idea where the guy sourced his seal kit but it was total crap. In less than two years the red shaft seal had turned to mush and was about 150% the size it should have been. If at all possible use genuine Stanadyne parts. The only exception is the aftermarket advance piston and bore sleeve.

 

[btmurph]

Thank you all for the response!

@welpro: LOL, I appreciate you trying to let me down easy... In this case replacing the IP is probably the easier operation as the fuel tank has more than 20 gals in it and I only have 3 empty fuel cans

@cucvrus: Good pics, thanks! I was having some trouble locating that darn sock online.

So lucky for me, I have a 6.5 humvee rebuild sitting in my shop with a new IP on it so I'll be pulling that one to replace this failing one. Another 2 questions if I may: Since the intake has to come off on both motors, would it benefit me to put the humvee intake onto my CUCV? Also, since I'll need to reprime the fuel system I'm going to switch to a spin-on filter and was thinking of putting a strainer like this one: http://www.fleetfilter.com/filter/33270.html near the tank and pulling the sock out... OK to do? Catastrophic failure will ensue? I wanna know

Thanks again folks!

Brian

 

[cucvrus]

Personally I would not put that in line fuel filter on. that is me. I am hard headed and think about the reasons pros and cons to everything. I say they lasted 30 years as is. Why change it now? That is just me. I just maintain what I have and keep it going as designed. Worked well for me for so many years so why change now? Do as you wish it is your truck. Thank you for your trust and best of luck. Keep the CUCV intake. No advantage to the HMMWV intake. I discarded many of them on my scrap pile. I have no use for them.

 

[welpro222]

The 6.5 humvee takeout will most likely have a 24volt advance sol. and shutoff switch. You may need to use the top cover assembly off of the old IP and install it on the 6.5 IP. Read the instructions when doing this, because if installed wrong it can cause a runaway engine when you first fire it up.

 

[cucvrus]

The 6.5 humvee takeout will most likely have a 24volt advance sol. and shutoff switch. You may need to use the top cover assembly off of the old IP and install it on the 6.5 IP. Read the instructions when doing this, because if installed wrong it can cause a runaway engine when you first fire it up.

Correct it is a direct swap. I have a HMMWV pump on 2 of my vehicles. The top of the pump and the pin on the throttle shaft for the shift modulator was all I had to change. Been a while but I think that was all.

 

[welpro222]

CUCVRUS, how do you go about installing the cover on the IP without running into the runaway problem? I haven't done it myself, but will be soon for my turbo swap.

 

[cucvrus]

The cover will slide towards the back of the engine when you remove the 3 screws from the top of the pump cover. Just let it slide back and remove it by lifting it off and out. When you are putting the CUCV pump cover on set it at the rear of the pump and slide it front gently and install the 3 screws again. Done deal.

 

[btmurph]

Thank you both for the input!

I will stick with the sock... replacing it when there's a little less fuel in the tank. I appreciate and respect the experience here, and if there's differing opinions I might weigh the facts but if I get a flat one opinion I'll follow the advice. The spin-on I AM doing... $30 apiece here for the box filter and now I've cleaned out my local Napa. I need a better option there!

The new IP is 12v as I had this motor built for a civvy truck application but I will compare the pins and swap parts as needed.

Thanks again! I will post the results... or maybe a swap thread!

Brian

 

[rsh4364]

If you do the spin on filter mod do yourself a favor and add a fuel pressure gauge.

 

[btmurph]

OK, so the new pump is in. The new pump is a 4911... and I've got 2 issues:

1. The timing now seems quite advanced. I started with the timing marks aligned and I had troubles keeping the motor running. I've now got the timing mark on the pump just BEFORE the mark on the engine and the rattle with the cold advance active is quite something to behold and seems somewhat excessive even after the advance kicks off. I will say the idle seems steady but darn the thing is really REALLY loud!
2. Not unexpectedly, I'm now producing a fair amount of black smoke. Not like those idiots with the super lifted trucks with the 12" dia. stack sticking out the bed but some smoke.

As far as issue #1, should I just retard the pump further? While this is my first 6.2l and I've seen many folks on the board complain about how loud these trucks are, I've been around these motors in the past and I don't remember anything even close to this level of rattle. Or am I just finally hearing what this motor should sound like? Am I going to run into issues retarding the timing much further?

With #2 should I turn down the fuel a bit or I do have the option of swapping in the 6.5l lines and injectors from the same motor the pump came from. Is there a tradeoff here? For me, if I can get away with turning down the fuel I think that would be my preferred outcome just so I can get my cutvee back on the road sooner!

Thanks again for all the help!

Brian

 

[cucvrus]

I have a HMMWV pump on my Crown of Thorns M1009. I had the same sound you are experiencing. I had to turn the adjustment screw on the side lever that runs along the pump to the bottom. I had to take that out 2 turns and then adjust as needed. You do not want to run it with that sound that is advanced to far. I have mine line to line and still have good power and the sound is normal now. Mine was advanced like you are describing and sounded like a tank when I came to a stop and pulled out. It is the little lever on the side. The bottom has a little allen screw. Turn that out 2 turns and try it there. Adjust as needed. Pull the lever carefully by removing a small E clip on the small shaft. Be careful and take your time. I have done it in the past. My M1009 never ran so good with that HMMWV pump on it. I think the pumps die so slowly that you never take notice till you get a new one on and see and feel the difference. Sort of like getting old and seeing a young guy working. Well maybe not the same.

 

[btmurph]

Thank you sir! I'll do that on Sunday when I can get back to the 09

 

[btmurph]

Backed out that screw two turns and the motor is definitely better but still loud... more like it should be I'm thinking Now it sounds nice a clattery (I hearby deem that a technical term ) but not like a jackhammer knocking through a ship's hull. This is with the timing just retarded. I MAY retard just a bit further but I'll drive it a bit a see. I've read elsewhere these 4911 pumps possibly run advanced in n/a 6.2l applications.

Those darn e-clips, I very carefully eased it off the shaft and at the last second it went poof! and disappeared into the ether never to be seen again! Luckily there's a hardware store locally that's open till 5 on a Sunday.

As it turns out the black smoke only happens if I really step on throttle so I'll probably not mess with the fuel screw after all... My driving style with trucks RARELY involves flooring it. Now to see how the mileage is...

Thanks again for all the help!!!