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Rod knockin'

Posted: March 12th, 2018, 9:21 pm
by Chris Haynes
I have developed a rod knock. Time to pull the pan and see whats happening. Hopefully the crank isn't damaged. That would open a big can of worms. I guess that answered my question whether my engine had poured or inserted bearings.

Re: Rod knockin'

Posted: March 13th, 2018, 1:25 pm
by birdacre
i had the same thing. engine nice for a month and then a knock started. the pin bearings or connecting rod journals were tapered one end to the other. some of the babbit even looked like it had been patched. i was lucky to find a good used engine, yeah right, he warranted it, said to drive it for a few weeks before paying him 200 dollars. to this day it is great. very lucky. my first engine came with the truck and no history and was a crap shoot. hope yours is ok, post updates. kevin

Re: Rod knockin'

Posted: March 14th, 2018, 10:19 am
by Chris Haynes
It may not be a rod bearing. My engine is still running smooth at idle and low speed.When I accelerate to mid range or higher it has a ferocious hard rattle.

Re: Rod knockin'

Posted: March 14th, 2018, 5:26 pm
by birdacre
i also grounded each spark plug one at a time to hear where noise was coming from. an old man showed me to also listen through a 30inch section of garden hose as well to ascertain the noise. hope all is well. kevin

Re: Rod knockin'

Posted: March 14th, 2018, 7:29 pm
by Stakebed
And your SURE its from inside the engine? Could be flywheel/clutch related. Does it do it in neutral when your stopped and revving the engine? Clutch depressed and revving VS released?

Is it only under a load? What about when in reverse? driveshaft can transmit sounds to many places...

Re: Rod knockin'

Posted: March 16th, 2018, 3:55 pm
by MrBill
mine recently started knocking too...when I shorted out the plugs number 3 cyl was the one and it made a double knock then...pulled pan and found piston pin loose in piston and others had loose pin bushings

Re: Rod knockin'

Posted: August 2nd, 2019, 5:52 pm
by Cschaff63
Chris Haynes wrote:
March 14th, 2018, 10:19 am
It may not be a rod bearing. My engine is still running smooth at idle and low speed.When I accelerate to mid range or higher it has a ferocious hard rattle.
Did you ever find that rattle? mine just started doing the same thing. My engine is a fresh rebuild by Antique Engines

Re: Rod knockin'

Posted: August 2nd, 2019, 11:19 pm
by Chris Haynes
It was all of my bearings.

Re: Rod knockin'

Posted: August 6th, 2019, 3:56 pm
by KimVanOrder
Chris Haynes wrote:
August 2nd, 2019, 11:19 pm
It was all of my bearings.
But what about the truck bearings? :lol:

Re: Rod knockin'

Posted: August 8th, 2019, 2:20 pm
by Cschaff63
I lucked out on this one, turns out my timing was too far advanced. Retarded the time, and the rattle stopped!

Re: Rod knockin'

Posted: August 11th, 2019, 1:30 pm
by Cschaff63
Cschaff63 wrote:
August 8th, 2019, 2:20 pm
I lucked out on this one, turns out my timing was too far advanced. Retarded the time, and the rattle stopped!
Well, maybe spoke too soon, when I retarded the timing, the rattle or clatter sound went away. Now it is back at a different rpm and under load mostly, I’m running a Zipper centrifugal distributor, is it possible it is not functioning as it is supposed to? Sure seems like it is timing related somehow!

Re: Rod knockin'

Posted: August 11th, 2019, 2:10 pm
by 1crosscut
Go back to the stock distributor set up and see if that helps. That way you will know if that is the problem.
You don't want to be running it if it is so advanced it's causing it to knock. Engines don't like that.

Re: Rod knockin'

Posted: August 31st, 2019, 6:24 am
by Cschaff63
1crosscut wrote:
August 11th, 2019, 2:10 pm
Go back to the stock distributor set up and see if that helps. That way you will know if that is the problem.
You don't want to be running it if it is so advanced it's causing it to knock. Engines don't like that.
Well, turns out the rattle was not timing related, I thought it was because I could change when the rattling occurred by adjusting the timing. It now shows up only under load, so dropped the pan and checked rod bearings. All the rod bearings are wiped! Engine builder says they appear to be oil starved. It is a fresh build with insert bearings and run through the proper break in cycle for first 100 miles. Oil levels were maintained. Did I maybe run the rpms too high when I took it on it’s first real road trip?

Re: Rod knockin'

Posted: August 31st, 2019, 7:28 pm
by 1crosscut
Cschaff63 wrote:
August 31st, 2019, 6:24 am
1crosscut wrote:
August 11th, 2019, 2:10 pm
Go back to the stock distributor set up and see if that helps. That way you will know if that is the problem.
You don't want to be running it if it is so advanced it's causing it to knock. Engines don't like that.
Well, turns out the rattle was not timing related, I thought it was because I could change when the rattling occurred by adjusting the timing. It now shows up only under load, so dropped the pan and checked rod bearings. All the rod bearings are wiped! Engine builder says they appear to be oil starved. It is a fresh build with insert bearings and run through the proper break in cycle for first 100 miles. Oil levels were maintained. Did I maybe run the rpms too high when I took it on it’s first real road trip?
That is very unfortunate. If your oil level was maintained and it is a fresh rebuild I don't see how your builder could say it was oil starved. Did you have lots of oil leaking out of the engine? A fresh rebuild should not need to have much if any oil added to it between 500 mile oil changes. If it is using oil to the point that you have had to add it regularly I would be quite unhappy with the builder.
I am old school and using a self advancing distributor is somewhat foreign to me as I like using a stock distributor and know that it will give excellent performance when used properly. I've read many posts on forums of folks that have had issues getting the "new fangled" distributor upgrades to work correctly.
That said perhaps it is possible that your non stock distributor if not set up correctly may have contributed to your troubles.
How many miles do you have on your engine?
Is it still under warranty?

Re: Rod knockin'

Posted: August 31st, 2019, 7:52 pm
by Cschaff63
1crosscut wrote:
August 31st, 2019, 7:28 pm
Cschaff63 wrote:
August 31st, 2019, 6:24 am
1crosscut wrote:
August 11th, 2019, 2:10 pm
Go back to the stock distributor set up and see if that helps. That way you will know if that is the problem.
You don't want to be running it if it is so advanced it's causing it to knock. Engines don't like that.
Well, turns out the rattle was not timing related, I thought it was because I could change when the rattling occurred by adjusting the timing. It now shows up only under load, so dropped the pan and checked rod bearings. All the rod bearings are wiped! Engine builder says they appear to be oil starved. It is a fresh build with insert bearings and run through the proper break in cycle for first 100 miles. Oil levels were maintained. Did I maybe run the rpms too high when I took it on it’s first real road trip?
That is very unfortunate. If your oil level was maintained and it is a fresh rebuild I don't see how your builder could say it was oil starved. Did you have lots of oil leaking out of the engine? A fresh rebuild should not need to have much if any oil added to it between 500 mile oil changes. If it is using oil to the point that you have had to add it regularly I would be quite unhappy with the builder.
I am old school and using a self advancing distributor is somewhat foreign to me as I like using a stock distributor and know that it will give excellent performance when used properly. I've read many posts on forums of folks that have had issues getting the "new fangled" distributor upgrades to work correctly.
That said perhaps it is possible that your non stock distributor if not set up correctly may have contributed to your troubles.
How many miles do you have on your engine?
Is it still under warranty?
I only have around 130 miles on the engine. The engine builder is sending me new bearings and pan gaskets! I kept checking my oil level and did not have to add any from original fill. I! Gonna replace the bearing and try again I guess. The timing was a bit advanced, but I can' believe that caused my bearings to wipe out