When I started home something happened and she started hammering under load. I also noted more of a blowby smell, but that could be me. I pulled over and listened, looked around, and it just does not sound bad at idle. It does not sound bad standing next to it and free revving it at the pump either. It only sounds like this when it is making power. It sounds to me like a gasser with a cracked manifold. Pressures and temps were normal, oil looks OK. Tomorrow I will give the coolant another look too. Here is a video for the sound. i was in stop and go, and it only chugs when making torque. I tried embedding it but not go. Click the link and tell me what you think it might be? https://youtube.com/shorts/f8LZUTyNjIQ?feature=share
Pop the valve covers look real hard at valve train. Missing button on rocker ??
It’s half crankshaft speed, so suspect valve train issue. Pop the covers off. Broken valve spring.
You might crack injector lines first to see if you can isolate the cylinder then look at the valve train. If it looks fine I would cut the filter too see what you see. If that looks good and there are no exhaust leaks (that's kinda what it sounds like to me in the video) I am not sure what it could be.
It does sorta have an exhaust leak sound to it. Good thinking.
thanks guys. broken valve spring and I might have some contact, or just an ugly leak at that valve?
It is at the truck shop now. We shall see what comes back and I will report.
3406B down! If those wheels ain’t turning’ you ain’t earning. Put me on the job. I can fix her up.
Reporting back with a six broken exhaust studs. Once one goes apparently the other ones are right along the way! Parts are on order.
Thanks for the update.
Those cat exhaust studs are the worst I have ever tried to remove. Normally, I will weld a handle on the stud and can back it out with a pair of vise grips. Every filler rod I tried, the weld would break off the stud and the end of the stud was glass hard. I then had to grind out the hard spot before I could drill the stud. I ended up making a drilling plate that would locate on non-broken studs and hold the drill bit on location to drill a pilot hole in the stud. I was then able to remove the broken stud with shop made un-easy outs.
Finally someone else that wont use the word easyout lol I can't remember the 3406b truck I did being to bad but I will never forget doing a cat loader last summer out in the mosquito filled gravel pit it had those glass hard studs in it 3 days drilling the only thing that would even come close to cutting was carbide bits they would last for half a stud or so Did a Mack last week and they all welded and unscrewed on the first try even though the break was recessed in the head quite a ways I was a happy camper!
Cat makes and or sold a drilling template for the 3406.
And special Artu drill bits
This is what is shown in "Dealer Service Tool Catalogue": However this does not seem to show the template that I recall the dealer using when we had some broken studs on a 3408. I had managed to remove all but a couple by welding nuts to the broken parts and removing them. Dealer guy also tried that with no luck. He then had a plate/template that bolted to the head and accepted bushings to guide the special drill bits to drill out the broken studs. I had a little better luck doing a 3306. Some studs took a few tries to weld on the nut to remove the studs but managed to get them all out. One trick that helped on some was to place a 3/8 inch flat washer around the broken stud and weld that to the broken bit and then place a 1/2 inch nut on top of it to weld to it. I think that gave you the ability to get better penetration into the stud and also put more heat into the broken stud so when it cooled a little it would shrink a bit.
I don't feel bad at all about letting somebody else do this job
It's one of those parts that are more about time and less about miles/hours. On the plane they would rust away. This engine only has 210,000 miles but it's 30 years old.
Broken Caterpillar exhaust manifold studs put bread on my table for many years.
ESAB All State Stud Plus welding rods. You'll never take below flush broken studs out another way.
Number 4 is the drill guide. Bob
Duly noted. I’ve had good luck with Brutus -AAA
Econoline E350 w/460...3 rear studs on each side. Had to bend the welding rod, though, as as they found it amusing to put the firewall/ floor pan in the way. Just plunge it into the hole and quit when it quits. Wait 10 seconds until slag pops off, then, lather, rinse repeat until above flush, then 7018 a nut onto. The stage coating the bore is the secret. I've also done ISX, ISB, and LS motors, all with same results.
Okay Guess from the lousy I was thinking that was just a piece of foam to keep the little parts in line! The only time we had to have a guy out to get studs we could not remove was probably ten years ago!
Those look like the ones I managed to get out of the 3306 in a loader. And I managed to do it with my little 120 volt Lincoln wire feed welder!
Dahm you're scaring me this sounds awful, my 3406B is 30 years old too and has over 300,000 miles on it.
It's the kind of thing that gets hard/corroded with age. I would not go looking for trouble though. It will find us when it wants
Where were the years ago when I needed them? Actually my 2013 Chevy 6.2 has a few broken.
I use these and nothing but these. Will start with out a center punch stay dead straight with out flex. Will drill the hardest steel and go through stainless in a zip. Can drill out 1/4" blind huck rivets staying dead center on the huck pin. I have drilled out I don't know how many broken studs dead center all the way through free hand. https://www.winzer.com/product/1-4-Mechanics-Length-Cyclone-3-Flats-Step-Drill
You get a drill to fit on an econoline or G van rear head? And, you don't get the heat and subsequent shrink from welding them
I have a rule-I worked on enough of that crud years ago, even at a Ford dealer for a short while. If the hood doesn't tilt and the engine weigh at least 2,500 lbs I'm not interested.
my truck is done and waiting. I am so pumped it was not internal.
Truck Shop, funny you mention those. I just ran across those Winzer drill bits for the first time, this week.
Oh I won't be. It runs great, and i'd swear the thing doesn't even burn diesel I constantly look in the tank because I swear the gauge hardly moves. An oil analysis came back really good. I ain't touching nothing. Only thing I want to do engine wise is a really good coolant flush and maybe it'll cool a bit better. The only thing I dislike about the truck is the low gearing, top speed of only 56 mph sucks, I don't want to run it above 1800.