#2 ConRod noise on 440

[JD-Me]

Hello good people.. What are the chances I can R&R a connecting rod for #2 cylinder on a 440 without pulling the engine? I ask because it is , of course, above the K member. Slim to none?
I suspect it is a spun bearing, but haven't looked yet.. just trying to figure out my spare time for the next few weeks .

Thanks,

 

[commando1]

I'd seriously consider a basic rebuild if I spun a bearing.

 

[GJS]

I agree with Commando on this. There'll be a lot of stuff in that block you're gonna want to look over before buttoning it up again. Whether or not it'd be possible to pop that piston with the engine in the car is secondary to the fact that you won't be able to inspect, flush or repair it thourogly in the car.

 

[Big_John]

It depends on a lot of stuff, but most likely, the crank journal is damaged if it's a spun bearing. Good possibility that the #1 connecting rod could have picked up some damage too.

 

[Wollfen]

The knocking noise coming from the upper part of the engine when it is running or is it lower?

 

[JD-Me]

The knocking noise coming from the upper part of the engine when it is running or is it lower?

No it's lower for sure. Initially I thought I might be hearing bum lifter or that metal on metal exhaust leak common to them (which still may exist), but definitely is a lower noise after a drive last week and goes away when the spark is taken away.
The ugh factor is the engine has only about 15000 since the motor was rebuilt (by a previous owner yr 2000 or so) but sh*t happens I know. Just throwing the hail Mary question out there as a sanity check ;) before I write off the season.
Thank you

 

[saforwardlook]

The crank will likely be junk and the rod will almost certainly need to be resized. You won't save any time and money trying to fix the "one problem" in the car. In fact, it will all be a waste of time IMO. Pull the engine in one afternoon and get it down to a good known rebuild facility that has been in business for decades and does racing engines too. They will have spare good used cranks too, more than likely, from other projects and likely use quality known good other parts to keep their reputation.

 

[Davea Lux]

As this is supposed to be a low mileage engine, I would pull the engine, remove the pan and heads and start checking things. First remove the bad rod and piston, very unlikely that the crank is undamaged. At the very least have the engine fully disassembled and tanked so it can go back together free of metal shavings. Then measure the bores for taper. Given it is a low mileage unit, the bores might still be ok. At this point, if the bores are within spec's, you might be able to install a fresh crank kit, rings and gaskets and put it back together. Trust you rebuilder on this. There was something clearly wrong with this engine that caused it to fail after such a short time and it could be a lot of things. Poorly balanced crank shafts are a leading cause of bearing failure as is low oil pressure. Be sure to install a new oil pump as part of the repair. A lot of "rebuilt" engines have had a set of rings and bearings installed in them to freshen them up. This low end rebuild approach usually ends badly as you now are no doubt aware.

Dave

 

[moper]

As Dave said - until you look you don't know. Two "givens" exist:
1. The head has to come off - and you are working over the fender to do it.
2. The crank will need to be measured very carefully, which is difficult to do right with the engine in the car.
My advice to anyone that has a lower end noise that is definitely lower end - pull the engine. Because in most scenarios you can't fix it in the car very easily. It's less work to pull and fix than swear and get hurt and filthy trying to fix it on your back.
Even factory new engines died at 15K. So it happens even in the best of cases. But more than likely it's a result of something being not quite right with that earlier rebuild. So tearing it down will give you solid intel on how it's doing and what needs attention.

 

[rags]

if the oil light's not flashing, could it be a wrist pin? i bent a rod in a 440 in my newport many years ago and was able to r+r it in the vehicle.

 

[saforwardlook]

if the oil light's not flashing, could it be a wrist pin? i bent a rod in a 440 in my newport many years ago and was able to r+r it in the vehicle.

The engine I received with a rod knock never had the oil light showing a problem (and it was functional).

 

[moper]

The oil light will come on if the engine sees oil pressure that's less than 10psi. The rods are the last parts to get oil. If the one rod is lose it's probably not enough to turn on the light. Now is the time to stop running it and pull it. The engine you save will be your own.

 

[Davea Lux]

Another thing that happens sometimes on rebuilt engines is that parts get mismatched. I have run across several over the years that had the wrong harmonic balancer installed. Several others with a weighted torque convertor on an engine that did not need one. All things to be aware of. Resized rods, if done improperly, can also be an issue in that rods so treated can wind up being "light" or too short. Not usually a big deal on a daily driver, but a really big deal on a performance engine. When you get the engine apart, resized rods will usually be marked, so check the one that failed. Pull your oil filter prior to pulling the engine, look for metal shavings coming out it as bearing failure usually puts lots of metal into the filter. This will help confirm that you do have a bearing failure and not something else. Another quick check is to pull the oil pump and check for bearing material stuck to the gears.

Dave

 

[rags]

i've seen rods spun so bad that they weld themselves to crank and have oil pressure. others'll be a little loose but not spin. in a v8 engine, hot with a low idle, i've seen those thunk a little and the oil light flash to the same rhythm. every engine is unique. question for dave above: is it true that a bad wrist pin is louder when when the plug is shorted?

 

[Davea Lux]

i've seen rods spun so bad that they weld themselves to crank and have oil pressure. others'll be a little loose but not spin. in a v8 engine, hot with a low idle, i've seen those thunk a little and the oil light flash to the same rhythm. every engine is unique. question for dave above: is it true that a bad wrist pin is louder when when the plug is shorted?

It is going to depend on just what is wrong with the wrist pin. The compression and firing cycle puts downward pressure on the pin which can tend to tighten things up and reduce some of the rattle or other noise if the pin is loose in the rod or piston. Removing pressure on the pin by deadening the firing cycle will usually cause the pin to move more and rattle or knock more. Most of the noise will occur as the piston and rod get to the bottom of the power stroke and start back up the cylinder on the exhaust cycle. It will rattle again as the piston is pulled down from TDC a to start the intake cycle.

If the pin has broken on either side of the rod and the broken part is rebounding off the cylinder wall, killing the firing cycle usually won't make much difference. In any case, an engine with a pin rebounding off the cylinder will not be long for this world and will often be scored past the point of feasible repair.

Dave

 

[rags]

thanks man. that's been my rule for distinguishing between a bearing or pin and how it happens. this guy's noise gets quieter, so more likely a bearing. thanks again, steve.

 

[GJS]

I blew a wrist pin in my 440 during an overheat situation. It was loud and killing the plug made little if any difference. In fact, I was only clear that it was a wrist pin once I pulled the head and looked in the cylinder. Pretty decent amount of score on the wall but I sure am glad I tore it down immediately or it would have gotten way worse.
To the poster's original query though I can only say; shut er down and rip er out. It's the only way to thoroughly assess and correct the situation... as much as I know how crappy it is to have to do that with only a couple of good months of riding left