Cold Knockin

[Chuckdiesel]

Lately at a cold start my motor has had, just off idle a rolling knock till the needle gets close to the first line. Theres no power right off till the clutch is engaged fully and at about 13 to 1500 rpms then the knock is gone an all is good. Never had that till reciently and it started round about when my GPs quit and for 2 weeks i had to plug it in whiched worked and then leaving work I had to use starting fluid I hope its only coincidence and not the cause

 

[Diesel JD]

I hope so too...bent rods would be no fun. Probably a fuel knock or bad lifters is more likely. Don't know. I'm still always worrying about noises on mine, I can't say for sure what is bad and what could be considered normal. Good luck

 

[93_E_350]

starting fluid

This stuff produces way to much pressure because it burns way to fast. If you got a 318 Detroit fine, else wise step away from the can...

 

[LUCKY_LARUE60]

Sounds to me you have air in your fuel system, the lack of power and a knock sure points that way.

Using starting fluid will not hurt a thing as long as you don't use the glow plugs at the same time. I have been around diesels engines all my life and most of them required starting fluid when temps were below 30*. I have had several Semis that had a COLD WEATHER STARTING AID from the factory. Many a diesel farm tractor had and still do have cold weather starting aid "starting fluid. I bought a NEW LTL9000 in 85 with a 3406B cat and it had a canister on the fire wall that had starting fluid in it. If it is so bad why would Cat still warranty the engine with it there?

 

[Chuckdiesel]

Ive heard bad things about starting fluid and diesels, but most likely the big trucks and equipment are built different I dont know. I tell ya man that rollin knock sucks. I do think I have an air leak. Would air in the return line cause a problem like that I know a fitting and ah hose that lives in the back on the drivers side that the RFL T-off is always damp and the fitting though screwed in tight is loose on the tubing.

 

[Agnem]

How old are your injectors? Might be time for a tune-up.

 

[93_E_350]

It could be an injector. If it's poping too soon it might cause pre-ignition.

 

[gabbyr100rs]

"If its poping too soon...."

Catholic injectors, perhaps--maybe they give up something during Lent??

 

[93_E_350]

"If its poping too soon...."

Catholic injectors, perhaps--maybe they give up something during Lent??

See now I won't have to go to church again for a while because I referenced a religious icon and it wasn’t used in anger

 

[Chuckdiesel]

Yea im thinking as soon as i can to replace the injectors and the fuel lines cause im shure that most everything is factory, with just 100K on the truck and the fact that it sat for 3 years till I got it Not much has been done.

 

[Diesel JD]

The thing I would do is take the injectors out and have them pop tested and checked for spray pattern at the fuel injection shop, which should test them for free or cheaply. Otherwise find another shop. If you're worried that you may have damaged the engine with the ether and want to satisfy your morbid curiosity, get hold of a compression tester that goes up to at least 600psi and will take a GP adapter. Then check for a piston that is 25% or more lower than the highest one. Ether damage usually manifests itself as bent rods or cracked pistons in an IDI. These trucks can handle ether if you use only a very little and do not use the glow plugs at the same time. The reason is that if even one glowplug is working it will possibly ignite the ether before you have a chance to turn the engine over possibly forcing it to start in an unnatural way and causing piston, glowplug or conn. rod damage.

 

[jtate]

chuckdiesel let me ask you a question have you adjusted the timing on the ip, it sounds to me like its a little to far advanced. as soon as it comes off idle does it also sound like it has an ignition knock like in a gasser?

 

[Chuckdiesel]

chuckdiesel let me ask you a question have you adjusted the timing on the ip, it sounds to me like its a little to far advanced. as soon as it comes off idle does it also sound like it has an ignition knock like in a gasser?

Yea sounds like a amplified spark knock and power is weak, witch makes getting the truck rolling a pain. 3rd and 4th are fine, well 3rd may knock some but mostly its at low rpms. Once its warm its fine still poor power at low rpms, I think a Mack can take me off the line I know compared to my bosses 89 250 NA 7.3 Im like a snail.

The timing has been advanced and for a while the truck was louder more clackety and quicker, before it was Quiet and sluggish. We used no method just moved it some like a dimes with to the right (Passenger side) worked as far as we knew then ti got weaker but still clackety and every once and a while i"ll have a random increase in power then it doggs out later in the day, it happed now and then but its been a while.

 

[Diesel JD]

Well you answered your own question...your timing is too far advanced. advancing the timing should have gained you some power but if its still a snail even with advanced timing it may be time for a full injection system overhaul. Yep, new injectors and pump. But I for one am confident that your knock is timing too far advanced or some combination of fuel system maladies. I would retard the timing about a dime's width or so and see if that knocking goes away. You really can't get perfect timing without the tools but static timing can be fairly close. You'll know you have it when it starts easy and gets good mileage is what I am told. For instance my pump is static timed/timed by ear, and it has acceptable fuel economy and starts good. I'm sure I'm giving up something but I am busy and have a hard time getting the truck to a qualified shop with tools. I know of a couple but as we pointed out in the timing thread this week they are far from being everywhere.