Pre 84 Trucks 1st gen pickups

"Low End Rod Knock"

Thread Tools
 
Search this Thread
 
Old 02-11-2013, 09:28 AM
  #1  
Registered User
Thread Starter
 
newomij's Avatar
 
Join Date: Sep 2005
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Cool "Low End Rod Knock"

1982 22R with the proverbial low end rod knock. This engine has less than 100K miles and runs very well except for the loud noise at rpm's above 2000. Can this issue be fixed without tearing down the whole engine?

'82 22R sitting in an '86 two wheel drive base pickup with a 5 speed. I did the engine/transmission swap and I am currently tearing down the original '86 22R that is going to need a lot of new parts. However, my budget is very limited. The '86 rebuild will happen but not quick enough to just swap it back into the above pickup. Therefore, the question above: Can the low end rod knock be fixed without dismantling the entire engine?

Thanks for the responses forthcoming. I've learned a lot here at YotaTech and really appreciate the information available here!!
Old 02-11-2013, 10:44 AM
  #2  
83
Registered User
 
83's Avatar
 
Join Date: May 2008
Location: Montana
Posts: 4,588
Received 125 Likes on 101 Posts
I think you could probably go in from under the truck. You'll have less space on a 2wd...on my 4x4, I can take the oil pan off without removing anything else, and get to the crank bearings from there. On a 2wd, I think your differential will be in the way, so I'm not sure.

You can, on a 4x4, just take off the oil pan and check out those bearings.
Old 02-11-2013, 10:47 AM
  #3  
Registered User
 
toyquad's Avatar
 
Join Date: Nov 2012
Posts: 94
Likes: 0
Received 0 Likes on 0 Posts
hows your oil pressure?

pull oil pan, inspect rod bearings. if the crank isnt to badly scored, put new rod bearings in.


well since your putting a new engine together for it anyway, throw new bearings in it regardless of condition. should last long enough
Old 02-11-2013, 10:48 AM
  #4  
Registered User
 
toyquad's Avatar
 
Join Date: Nov 2012
Posts: 94
Likes: 0
Received 0 Likes on 0 Posts
hows your oil pressure?

pull oil pan, inspect rod bearings. if the crank isnt to badly scored, put new rod bearings in.


well since your putting a new engine together for it anyway, throw new bearings in it regardless of condition. should last long enough
Old 02-11-2013, 05:13 PM
  #5  
Registered User
Thread Starter
 
newomij's Avatar
 
Join Date: Sep 2005
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
low end rod knock...

Is this "low end rod knock" a rod to crank bearing problem then??? Could it be something else?
Old 02-12-2013, 06:11 AM
  #6  
83
Registered User
 
83's Avatar
 
Join Date: May 2008
Location: Montana
Posts: 4,588
Received 125 Likes on 101 Posts
Well, as far I know, rod knock is from rod bearings. But as to whether the noise you're hearing is rod knock, there's no way for us to know over the internet. We just kind of have to take your word for it.
Old 02-12-2013, 09:45 AM
  #7  
Registered User
Thread Starter
 
newomij's Avatar
 
Join Date: Sep 2005
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Thank you for the help. I've had a couple of people tell me that the sound was/is 'low end rod knock'. By the time I'm done with all of this I will be very tired of that phrase. Wish me luck!!
Old 02-12-2013, 11:19 AM
  #8  
83
Registered User
 
83's Avatar
 
Join Date: May 2008
Location: Montana
Posts: 4,588
Received 125 Likes on 101 Posts
Yeah, good luck!

As far as my engine knowledge (which is limited) tells me, the thing that keeps your rods moving smoothly are the bearings on the crankshaft where it connects to the rods. If those are going, you'll get some rod knock.

The only other thing that would allow movement of the rods would be if your cylinders were so worn out that there was a relatively large gap and the piston heads were rattling around in them on each stroke. That, to me, seems pretty unlikely, and I think if it were the case, you'd be looking at some catastrophic engine failure sooner than later.

What's moving around in the bottom of you engine block is the crankshaft, which has the rods attached to it. I guess your crank itself could be loose...but I'm not sure I've heard of that happening.
Old 02-13-2013, 06:48 AM
  #9  
Registered User
iTrader: (1)
 
gillesdetrail's Avatar
 
Join Date: Jan 2013
Location: Montreal, qc
Posts: 803
Likes: 0
Received 1 Like on 1 Post
put some 20w50 oil, retard a bit of timing and baby it and it should last until the other motor is rebuilt. I have a friend last 3 years of hard trail driving with a very bad rod knock until the engine let go (hole through the block).
Old 02-19-2013, 03:20 PM
  #10  
Registered User
Thread Starter
 
newomij's Avatar
 
Join Date: Sep 2005
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Red face

Ok. It's been a few days but I managed to get a round 2it. Got the oil pan off and exposed the crank. Looking for this low end rod knock, is there going to be something obvious to look for?? (besides scaring of the crank), or will I be replacing all of the lower rod bearings?

In case someone else reads this thread thinking about doing the same thing... to get the oil pan off, I had to remove the cross member under the pan and I, also, had to loosen the steering arms to lower them out of the way. To accomplish that, there is one piece of the steering linkage on the passenger side that is bolted to the frame with three bolts. After I removed those bolts, and lowered one end of the shock connected to the linkage, it all lowered far enough to easily remove the pan. Had I not done that, the pan would not have had enough clearance for removal.
Old 02-19-2013, 03:58 PM
  #11  
Registered User
 
79pickupian's Avatar
 
Join Date: Jul 2011
Location: San Diego, CA
Posts: 20
Likes: 0
Received 0 Likes on 0 Posts
Originally Posted by newomij
Ok. It's been a few days but I managed to get a round 2it. Got the oil pan off and exposed the crank. Looking for this low end rod knock, is there going to be something obvious to look for?? (besides scaring of the crank), or will I be replacing all of the lower rod bearings?

In case someone else reads this thread thinking about doing the same thing... to get the oil pan off, I had to remove the cross member under the pan and I, also, had to loosen the steering arms to lower them out of the way. To accomplish that, there is one piece of the steering linkage on the passenger side that is bolted to the frame with three bolts. After I removed those bolts, and lowered one end of the shock connected to the linkage, it all lowered far enough to easily remove the pan. Had I not done that, the pan would not have had enough clearance for removal.
You can check for play using a dial gauge, or just kinda do it by feel. If its very loud you should be able to see some scoring or see excessive play on a dial gauge indicator.
Old 02-21-2013, 01:01 PM
  #12  
83
Registered User
 
83's Avatar
 
Join Date: May 2008
Location: Montana
Posts: 4,588
Received 125 Likes on 101 Posts
I'd just replace them...

Although I'm not sure how much scoring on the crank it takes before just replacing bearings isn't enough, and you need the crank machined, too.

But if you're going on the assumption, from what people have told you, not knowing anything yourself, that you have rod knock, I wouldn't suddenly expect you to be able to tell a good bearing from a bad one and decide whether or not they need to be replaced....

You got in there to do it, I'd just go ahead and do it. Otherwise bring it to someone who actually knows. I don't know how to tell bad crank bearings. I guess I'd need to look up the definition of a bearing, but I'm not even sure how they get away calling those things bearings...

The kind of bearings I'm used to, I can tell when they're bad.
Old 02-25-2013, 06:55 PM
  #13  
Registered User
Thread Starter
 
newomij's Avatar
 
Join Date: Sep 2005
Posts: 9
Likes: 0
Received 0 Likes on 0 Posts
Completed the rod bearings swap. After moving the cross member out of the way and loosening the steering arms enough to lower them so the oil pan could be easily removed and reinstalled, the rest was pretty simple. It took a little effort to get the lower rod bearing caps off because they were kinda stuck but just the right pressure and a big hammer and they fell right off. (Just kidding about the hammer Fortunately, the crank was not scarred an any way so I didn't have to deal with trying to pull that out which, thinking about it, I don't think would be possible without separating the engine from the transmission. Not too sure about that but... So, looking at changing the rod bearings from under the vehicle is a reasonable adventure if it turns out the crank is ok. If it's not ok, then the real work begins but if it is ok, you've saved a lot of time.

Thanks to yotatech guru's and the willingness to dive in, I got mine fixed and it sounds pretty good.
Old 02-26-2013, 06:26 AM
  #14  
83
Registered User
 
83's Avatar
 
Join Date: May 2008
Location: Montana
Posts: 4,588
Received 125 Likes on 101 Posts
Good work!

Yeah, I can't remember exactly how my engine came apart...but I don't think you can take the crank out without digging in a lot further than you did.
Old 02-26-2013, 07:11 AM
  #15  
Registered User
 
kelvinb's Avatar
 
Join Date: Aug 2012
Location: denver colorado
Posts: 388
Received 9 Likes on 8 Posts
i had a similar issue with my 22re. i had a low end knock and i replaced rod and main bearings along with the thrust washer. i also lucked out with the crank not being scarred. the main bearings all had a scratch in them. the rod bearings were fine but were replaced anyways.
Related Topics
Thread
Thread Starter
Forum
Replies
Last Post
Flying91
86-95 Trucks & 4Runners (Build-Up Section)
45
04-11-2024 04:39 PM
Charecter1
86-95 Trucks & 4Runners
10
11-06-2023 10:08 AM
bigjstang
86-95 Trucks & 4Runners
20
08-25-2021 12:41 AM
icentropy
86-95 Trucks & 4Runners
22
09-16-2020 02:47 PM
GreatLakesGuy
The Classifieds GraveYard
8
09-04-2015 09:27 AM



Quick Reply: "Low End Rod Knock"



All times are GMT -8. The time now is 01:38 PM.