Rod Knock on rebuilt 2H engine (1 Viewer)

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I recently (3 months ago) rebuilt my 2H engine on my 1989 60 Series Cruiser. Complete rebuild, sleeves to OEM oil pump. Everything on STANDARD spec. decent parts
REASON FOR REBUILD: poor compression noticeable from tappet cover breather and sludge buildup in motor oil. Also intend to supercharge with an Eaton M90 (pending)
I'm no mechanic but have built a number of engines before. Still no messing around with the sensitive things I contracted a mechanic for the rebuild, an old timer with lots of experience specifically older diesel engines.
Rebuild was smooth and perfect. Perfect start, ran beautifully, extremely satisfied save an oiling problem on the rockers (the reason i bought the oil pump) - still no improvement - ended up being wear in the grooves of the rocker shaft - pulled one off another 2H - problem solved!
Did the routine standard running in and drove as usual for about a month - no issues - no concerns whatsoever until the day before I was due to make +900 km trip deep into remote Africa for work! CLEARLY A KNOCK FROM THE ENGINE! I really must have some angels watching over me 😅😅😅
Desperate to find out what was wrong I got mechanic in to check everything eventually dropping the sump to inspect the cranckshaft and to my horror i was able to shake the conrods a little without much effort (up, down and sideways). Loosened the conrod bolts (still torqued and very secure so thats ruled out) to have a look at bearings which showed visible wear (no copper though), even more than the old ones removed for rebuild! see attached photos

I had to arrange another car and traveled as intended. I will be returning in a week and hope to sort it out. I know i have to pull the motor out again but have no idea what could have caused this problem or a solid solution. The mechanic i worked with has experienced all sorts of knocks but never a Rod Knock so thats not much help.
Can anyone suggest a solution or possible cause for this problem I really am lost and would like to have a gameplan for how to approach this when i get back. Really miss the old girl.

Not sure if this matters, i used Shell RIMULA Heavy Duty Engine Oil R6 M Fully Synthetic 10W-40

OLD BEARINGS.jpg


After Rod Knock.jpg
 

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Do you have this problem for every connecting rod or just one? did your mechanic check the bearing clearances during assembly?
 
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You need plastigage to find out what your bearing clearances are. Could he have used stock size bearing shells after turning the crank down? Is the oil pressure high (or where it should be)? If the rods can be moved up/down/around, they sound quite loose.
 
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All consistent and make sense I appreciate the replies. Pretty clear what I have to do. I feel like I've been messed up by this Mechanic and I don't want to risk this again. Is this something I can do at the engineers? Auto machine shop? They should have all the precision measuring tools/machines. And what do they do exactly? Tell me I need to go a size up on the conrod bearings to solve the problem? Any other solutions?
 
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You need plastigage to find out what your bearing clearances are. Could he have used stock size bearing shells after turning the crank down? Is the oil pressure high (or where it should be)? If the rods can be moved up/down/around, they sound quite loose.
Sorry if this is stupid but what does "turning the crank down" mean? Yes he used stock size. Everything was standard. the oil pressure is where it should be. Are you suspecting blockage in the oil passages? Poor lubrication would burn the conrod bearings blue or darker im guessing
 

FJBen

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All consistent and make sense I appreciate the replies. Pretty clear what I have to do. I feel like I've been messed up by this Mechanic and I don't want to risk this again. Is this something I can do at the engineers? Auto machine shop? They should have all the precision measuring tools/machines. And what do they do exactly? Tell me I need to go a size up on the conrod bearings to solve the problem? Any other solutions?

they just need to measure the crank and fit the appropriate bearing so it has the correct clearance.
you can measure this with a digital caliper.
Correct you get oversized bearings on the crank if it’s been turned down.
Basically means they took some of the crank metal down as itnwas pitted/scarred etc to a smooth polishable surface. When you do this, your bearings need to be slightly thicker to make up the difference. It’s in the manual what the clearance needs to be.
there are only so many sizes of bearings so there is a range so to say for turning down or grinding the crank.
 

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If you have access to plastigage, you can easily yourself determine if the clearances are OK. plastigage is a piece of deformable plastic that is sized for the expected bearing clearance. a small piece is cut and laid across the journal surface. the bearing is then installed and torqued to spec and then removed. You recover the plastigage and measure how much it deformed. This tells you what the clearance is. You would compare this to the specification in your service manual. After you source the plastigage, it is no more difficult than installing and removing the bearing/cap. My 2F engine manual has this procedure as part of servicing the cylinder block.

Here is an example from amazon and you can google it to see videos, etc.


Another option would be to use a micrometer and measure the outer diameter of the connecting rod journal surface (called the "crank pin" in the 2F engine manual) on the crankshaft and compare this to the specification in the service manual. "turning the crank" means the journal surfaces on the crank are machined smaller to remove any wear or scratches. If this is done, then bearings that are thicker (AKA oversized) are used to keep the gap clearance within specification. the backside of the bearing may have a stamp that says if it is standard or oversized (and by how much).
 

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  • plastigage on 2F connecting rod.pdf
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And you guys decided to sleeve the cylinders as a cheaper route to overbored and hone? I’m gathering that’s what you meant by sleeved...
hi, I didn't really consider price to be honest just figured go the whole 9 yards fit new sleeves while im at it and keep everything standard (stock) spec. Fitting, boring and honing all done professionally at auto engineers.
 
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FJBen thankyou for simplifying it for me really appreciate that. And also thank you everyone for advice on plastiguage, micrometer, calipers I can get my hands on them and would save me a lot of money but after what happened im not feeling too confident. I'm thinking take it to Auto engineers and get it right once and for all. I'm not taking any chances especially with how remote the places I'll be driving to are!
So in a nutshell, what would I ask for from the auto Engineers? this will help me get quotes and budget for it.
My old man reckons it's worth Checking Crankshaft Bow ( highly unlikely given how balanced the engine was running).
I'm hoping all they need is the crankshaft for this task and they'll advise on the new conrod bearings I need to buy. Too easy?
 

NeverGiveUpYota

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Sorry if this is stupid but what does "turning the crank down" mean? Yes he used stock size. Everything was standard. the oil pressure is where it should be. Are you suspecting blockage in the oil passages? Poor lubrication would burn the conrod bearings blue or darker im guessing
Turning the crank down would mean he ground and polished the journals... which sounds like he didn't do. Which is why you stated
Everything on STANDARD spec. decent parts

the whole 9 yards
Okay, here goes number two... new lap top and if I hit the wrong key I highlight and delete everything I wrote... which I just did.
What I was saying was.... IF all you did was sleeves on standard decent parts, then that isn't a full rebuild. That is a band aide.
To grind and polish the journals which they mean by turn down, the actual journals are ground and polished... Hence why you'd need to measure the clearances and buy smaller bearings, or thicker as stated previously.
I have a 60, 2F, petrol not deisel like yours. Surely there are differences between the two but the basic mechanical parts I will wager are the same. I've been in and out of the engine more times than most in my driveway. I've pulled my cam while the engine was still in the truck. I've done kinda dumb stuff but pulled it off every time.
The reason I pipe in is my block is on a stand now in my garage. I was having some coolant loss, steam/smoke from the top of the engine and a compression test revealed numbers that hadn't changed from two years prior when I had the head rebuilt with new valves. I did two leak downs tests myself and found it leaking 10-15%. A second shop told me my head was fine and to just run it. I didn't agree and after some hemming and hawing and ignoring many folks here on mud, I pulled the offending pistons 2&5 and found they had broken landings and a third had broken rings. All on my own I pulled my block and brought it to a shop. They went over it, over bored, honed to new over sized pistons I bought. And I am doing the full assembly myself. I say all on my own because I am a 5'5" 130lb female.

Do yourself a favor and follow the suggestions above. Do NOT bring your crank to a shop. You can do it yourself as the guys above explained. If you think you can not, then do the truck a favor and do this the right way and pull the block and get it to a shop with the crank, cam and head who can do it all for you. A shop can't tell you squat on the crank without the block to assess as well.
IF you have a knock then I would be concerned with your cam... how did it look? Especially since you stated
ended up being wear in the grooves of the rocker shaft

How did the lifter rods look? did you roll the rods on glass? one could be bent. I ask because I had one bent and now I know that you need to check them in a rebuild.

Lots of guessing and missed steps in this rebuild. You'll be throwing money where you may not need to or at the wrong system if you keep going this way.
 
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Turning the crank down would mean he ground and polished the journals... which sounds like he didn't do. Which is why you stated



Okay, here goes number two... new lap top and if I hit the wrong key I highlight and delete everything I wrote... which I just did.
What I was saying was.... IF all you did was sleeves on standard decent parts, then that isn't a full rebuild. That is a band aide.
To grind and polish the journals which they mean by turn down, the actual journals are ground and polished... Hence why you'd need to measure the clearances and buy smaller bearings, or thicker as stated previously.
I have a 60, 2F, petrol not deisel like yours. Surely there are differences between the two but the basic mechanical parts I will wager are the same. I've been in and out of the engine more times than most in my driveway. I've pulled my cam while the engine was still in the truck. I've done kinda dumb stuff but pulled it off every time.
The reason I pipe in is my block is on a stand now in my garage. I was having some coolant loss, steam/smoke from the top of the engine and a compression test revealed numbers that hadn't changed from two years prior when I had the head rebuilt with new valves. I did two leak downs tests myself and found it leaking 10-15%. A second shop told me my head was fine and to just run it. I didn't agree and after some hemming and hawing and ignoring many folks here on mud, I pulled the offending pistons 2&5 and found they had broken landings and a third had broken rings. All on my own I pulled my block and brought it to a shop. They went over it, over bored, honed to new over sized pistons I bought. And I am doing the full assembly myself. I say all on my own because I am a 5'5" 130lb female.

Do yourself a favor and follow the suggestions above. Do NOT bring your crank to a shop. You can do it yourself as the guys above explained. If you think you can not, then do the truck a favor and do this the right way and pull the block and get it to a shop with the crank, cam and head who can do it all for you. A shop can't tell you squat on the crank without the block to assess as well.
IF you have a knock then I would be concerned with your cam... how did it look? Especially since you stated


How did the lifter rods look? did you roll the rods on glass? one could be bent. I ask because I had one bent and now I know that you need to check them in a rebuild.

Lots of guessing and missed steps in this rebuild. You'll be throwing money where you may not need to or at the wrong system if you keep going this way.
Ok. lots of things on my mind after reading this. Thank you for enduring through and laying this out for me Yota. Quite demoralised with the "band aide" comment - I was really hoping not to open up this engine again in my lifetime - sucks im so far away and can just get straight into it and deal with it.
Correct: the journals were not polished - they were in good condition, nor did mechanic bring it up - lesson learned!
Cam shaft was inspected - all good - no concerns but will check again for good measure. same goes for push rods, i had that problem on my other 2H so im well aware of push rod issues.
I'll take the advice and see how i fare with all the pointers above. I totally get your experience with the machine shops makes me uneasy too just for lack of a better option.
Definitely inspired by the full assembly on your own . Thanks again
 

FJBen

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So...sleeves aren’t necessarily a bandaid.
a chunk of Toyota’s diesels came with them Factory. Lots of pluses on sleeves. You can replace scored cylinder walls without having to overbore. Oversized sleeves exist as well.

the 2H came with and without sleeves.
according to @lostmarbles
Nov 1984 was the change from sleeved to sleeveless for the 2H I believe. (Independent of country and independent of application)

depending on the market of the truck, year and if that’s the original engine. Might be worth talking to the mechanic to see if it had sleeves or not when he tore it down.

You can do a full rebuild with all new oem spec parts and put sleeves in. Usually that’s because it’s been too far bored, or some damage has occurred that can’t bore out.

I would also see if he did grind the crank any. If he ground the crank and used standard spec bearings, that might explain it. Crank grinding/polishing and sizing right bearings is very standard stuff...but mistakes sometimes happen.

see if you can get a digital caliper on crank. That will tell all.
Do you have the boxes or part numbers for the bearings?
 

NeverGiveUpYota

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So...sleeves aren’t necessarily a bandaid.
a chunk of Toyota’s diesels came with them Factory. Lots of pluses on sleeves. You can replace scored cylinder walls without having to overbore. Oversized sleeves exist as well.

the 2H came with and without sleeves.
according to @lostmarbles
Nov 1984 was the change from sleeved to sleeveless for the 2H I believe. (Independent of country and independent of application)
Good to know. Thank you for correcting me on the sleeves.
 

FJBen

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Good to know. Thank you for correcting me on the sleeves.

😁 In foreign cruisers especially I’ve learned anything is possible. Just when you think it doesn’t exist, it will will show up with those options.

I rebuilt the 13bt in my BJ74 (hose blew on highway before i got it) and the cam bearings i had to order 3 times from Toyota to get the “right” ones. after measuring and researching I ended up buying cam bearings that were built for a 14b motor. :meh:

the best way is to measure what you need for crank bearings and make sure to get the right ones, as sometimes even Toyota is wrong.:cool:
 
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I did my research on that and when ordering parts from Australia I was told the my engine was parent bore based off the serial number on my engine. So I was quite surprised to find liners in there when we took the head off thats why I replaced with new liners/sleeves. Clearly the engine was built before.
I've only ever owned diesel 60's and I'm really satisfied with with the way the engine ran after the build. I'll give the mechanic a lot of credit for that he got all the tuning spot on.
That ghastly Rod Knock is the only problem I hope. Worrying too how it just happened suddenly, no gradual build up to the knocking sound. So random, and so loud!
I have the boxes and numbers but there 900km away so that'll have to wait a week till I'm back, will try find the part numbers from invoices I was emailed.
Will use a digital caliper on the crank thanks.
 

NeverGiveUpYota

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Will use a digital caliper on the crank thanks.
Plastigage is even easier. As stated...
plastigage is a piece of deformable plastic that is sized for the expected bearing clearance. a small piece is cut and laid across the journal surface. the bearing is then installed and torqued to spec and then removed. You recover the plastigage and measure how much it deformed. This tells you what the clearance is. You would compare this to the specification in your service manual. After you source the plastigage, it is no more difficult than installing and removing the bearing/cap. My 2F engine manual has this procedure as part of servicing the cylinder block.
I don't believe you can use simple digital calipers on the crank. They require a micrometer, I believe.

IMG_9987.JPG


This was a few weeks back when I was checking mine in the garage.
 

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