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My 93 having a mysterious tapping or knocking under acceleration that comes and goes

I suppose rebuilding some injectors are next on the list. though it's gonna be fun getting this turbo off to get at the passenger side.

I'm curious if an injector noise or knock can come and go like this and be mistaken for a lifter or knock.
 
Welp, I guess I could attempt to remove the turbo. I will get the intake and all buttoned back up today, then see if I can get a set rebuilt and ready to go in. been wanting to do that anyway. idk the condition of the injectors that are on this engine or how long they've been on it. I would assume they were installed used when this engine was put in or were on it when it was installed. given all the used injectors that I was given with the truck, I believe it was all put together on the cheap. sounds like something I would do LOL
 
Finished up rebuilding a set of injectors and got them installed. That went surprisingly too well! After removing the IP lines and getting them out of the way I was able to get all 8 removed and installed without having to pull the turbo!

I have all 8 old ones laid out on my bench to test later but curiosity was getting me so I chucked #6 on the tester and it blew its load at around 1500 psi!!

Now to get the IP lines back on and button up the rest of the engine.
 
Well it runs.... I had did a video of it running with my phone even revved it half way to the moon and back a couple of times but unfortunately for what ever reason my phone didn't record it. this new iphone 15 must not like me that well!

good news is it idles smooth and while revving it up guessing up around 3500 I don't hear any knocking or ticking sitting in the driveway. it does seem to be clattering slightly louder I think due to the injectors are now at a higher pressure or set where they should be at. I also stood on the brake, dropped it into gear and hit the go pedal. LOL it overpowered the brakes and lurched forward!! I wasn't expecting that and about knocked all my tools off from under the hood LOL

I will take it out tomorrow sometime and see if that noise re-appears.

also want to run all the old injectors I removed through the pressure tester to see what they were doing. I did test the one from #6 and it popped off at 1500 psi so not sure if low pop pressure would attribute to that. maybe the weak pressure might have been causing them to leak some at the wrong time causing a cylinder knock? idk but time will tell.

what's that old saying? idk if it's fixed but it's different!
 
So I forgot to mention yesterday that after I got it running again. I had pulled the oil cap and removed the tube coming from the CDR and oil catch can so I could see how much blow by was evacuating from the engine.

after it has warmed up I revved it up pretty high and held it there. I noticed that almost all of the blow by that was being pushed from the engine almost completely stopped at high RPM. is this normal? I would have thought that without anything pulling the blow by that it would have gotten worse at higher RPM.
 
'Is this normal?' Yes.

The old Heath Diesel page used to list a testing for blow by that involved visual checks at idle and vacuum pull at higher RPM (2500 IIRC). The aim was to not have people prematurely condemn their motors. I no longer have the document in digital or printed form (I know, disappointing) but, 'if memory serves' it went like this....

With the engine warmed up, the oil cap secured and the dip stick removed, run a long length of clear hose from a glass or bucket of water up and over the dip stick tube. At idle, the water level in the hose should stay at the water level in the bucket or a little lower. With the engine RPM increased to 2500 rpm, water should be pulled up the tube about an inch or two. Water WILL NOT be pulled up into the motor so relax. IF water is pulled up the one to two inches, you've still got life in the engine. I'm guessing, the higher the water gets in the hose, the better.

I did this early on (2008?) with my old engine which had easily visible huffin' and puffin'. The engine passed so I knew it was alright for a while.

Bill is drag racing his gasser truck with one of his former employee's driving one of his previously owned 6.5s. I'll ask him when he gets home if he's still got the write up.
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Interesting. I wonder if this test is done with the CDR and tubing disconnected from the turbo so it can't pull anything from the turbo spooling up.

I know this old worn out engine when you first crank it up cold with all the CDR tubing off and the oil cap off, there is hardly any blow by at all when it bone cold. as soon as there is a tiny amount of heat in the cylinders (run for a couple minutes) it starts puffing the smoke.

This test might be something we could try and then add maybe a bottle of Lucas oil stabilizer and then a can of engine restore testing for claimed compression restoring.

I was actually thinking about dropping a quart of the Lucas in this engine the other day since the weather is warming up. considering this engine is a 99 model though I have not tried to get the block cast numbers, I think it has the piston oil squirters. the Lucas treatment might help.

I remember back in the day I had an old jeep cherokee that had a GM 2.8 v6 in it. it had a bad rod knock due to it being externally balanced. someone had done some parts replacements. I can't remember but the same engine in a GM vehicle was built different and the flex plates and harmonic balancers were weighted differently than for jeeps with the same engines. anyhoo it had t he wrong flex plate or balancer causing the vibrations to take out a rod bearing.

I replaced them with the correct parts and then dropped the pan installing a new bearing on that rod. still knocked pretty bad. dumped two bottles of that lucas stabilizer in the engine and drove it for another year till I sold it. that motor honey kept it alive all that time LOL
 
I feel like if I did this test now, it would "blow bubbles" in the water in the bucket, but revved up It might draw some up slightly or be at the same level as the water in the bucket. now with the CDR tubing attached, It might actually draw some up the tubing, maybe.
 
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