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Found the cause of the knocking


Marco79

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Ive copied my build thread from another forum but really would like te input as I've never known a someone rpto forget a bearing or even one to disappear on stock boost

 

Had another hit today and found bad news :(

 

I removed the con rod ends and found No1 had no clam shell bearing AT ALL!!!!

 

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Looking at the others 2,3,4 and 5 were good but 6 was very worn

 

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these are the caps which seem ok

 

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apart from no6 again which has some wear, this was also similar to no1 but slightly worse

 

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Here are the clamshell bearings from 2 (l/h) to 6 (which you can see is very worn!

 

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I then spun the engine round and pulled the cam covers off the exhaust side to check the cam journals

 

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I found some slight (imo) speckles of metal but is this acceptable i dont know?

 

 

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but this was between 3,4 and 5 with nothing on 1 and very minute amount on 6!

 

i numbered the cam caps by numbering with a centre punch and the dots are alway facing aft on the outboard side so i cant get them mixed up

 

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removed the cams and all looked nice and clean

 

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I did this for the intake side with similar results.

 

All in all i cant (imo) see enough metal debris to indicate there ever being a bearing in No1! what are your thoughts guys this is really bugging me as i hate not understanding how something like this can happen!?

 

I went to remove the head but dam hose bolts are tight

 

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So with that i called it a day leaving the engine like this

 

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You can never be too cautious ;)

 

Well they are a matched set from the factory so if they were in the wrong positions I wouldn't be surprised to see wear. I would always go with what Toyota stamped on them rather than the order the last person to take them off put them on in.... especially given that you have a bearing missing.

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Well they are a matched set from the factory so if they were in the wrong positions I wouldn't be surprised to see wear. I would always go with what Toyota stamped on them rather than the order the last person to take them off put them on in.... especially given that you have a bearing missing.

 

Fair point dude so what is the numbering for each cylinder and where is the numbering found bud?

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Fair point dude so what is the numbering for each cylinder and where is the numbering found bud?

 

The front bearing cap is cap 1, 7 is the rear most cap. You can tell because the front cap is the different shape/design one for the front of the camshaft & seal.

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The front bearing cap is cap 1, 7 is the rear most cap. You can tell because the front cap is the different shape/design one for the front of the camshaft & seal.

 

Makes sense :) will double check tomorrow they coincide with my markings and that will confirm/ eradicate that! I just don't know how anyone could miss out a bearing!!!!!

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In the picture number 3 the bearing is still on the rod tap. iam thinking that that bearing just seized and spun the bearing inside the cap. iam pretty sure that there would be bearing in all conrods or it would have sounded horrendus. The bearing should not rotate inside the bearing caps thats kinda the only way you would see anykind of wear in the caps and on the outside of the bearing. the wear should be inside the bearing. not to be an arse but your crank looks like scrap.

 

Kenblockseal might have a crank for you.

 

also you need to really flush the engine and cylinderhead.

Edited by Hellstrom
typos (see edit history)
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In the picture number 3 the bearing is still on the rod tap. iam thinking that that bearing just seized and spun the bearing inside the cap. iam pretty sure that there would be bearing in all conrods or it would have sounded horrendus. The bearing should not rotate inside the bearing caps thats kinda the only way you would see anykind of wear in the caps and on the outside of the bearing. the wear should be inside the bearing. not to be an arse but your crank looks like scrap.

 

Kenblockseal might have a crank for you.

 

 

also you need to really flush the engine and cylinderhead.

 

 

Your not being an arse mate I know it's scrap and already pm'd ken ;) if there was a bearing in NO1 it's totally dissintegrated and left no sign off it in the engine! Yes it would have sounded like a Sherman tank which is also why I'm confused as I was informed it only had a slight knocking!

Defo need to flush the head, I'm concerned about the head as hate the thought of bits floating around the head

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Well the head can be cleaned no problem i just cleaned my head using a hi pressure washer with hot water. just make sure to disembly the whole lot. regarding the cam journals there might be that the head has warped then you would need to linebore the cam jornals and get the head flat. however i really doubt it will be worth the money. probebly the head has gone aswell can't really tell from the pictures. Also as iam messuring my crank myself. i think that you would need to also replace the maincaps as the crank will be slightly diffrent probebly and to aviod to linebore the main journals. you would also need the caps. (this iam not 100% certain off just that iam messuering my crank and it has a number code for each journal and the tollerance is 0.002mm and there are 5 steps iirc so i guess if you just changed the crank i could meen less oil clearence for the bearings. ask Chris wilson maybe?)

Edited by Hellstrom
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If replacing the crank you will definitely need to replace the main bearings. Not sure about the big end bearings.

 

The crank will need bought and sized to see what main bearings are required.

 

The caps are matched to the block so those won't be required as long as the bearing spinning hasn't caused any damage. If the caps are damaged you will need new ones and the block line-bored to match. Cheaper to buy a 2nd hand block though IMO.

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If replacing the crank you will definitely need to replace the main bearings. Not sure about the big end bearings.

 

The crank will need bought and sized to see what main bearings are required.

 

The caps are matched to the block so those won't be required as long as the bearing spinning hasn't caused any damage. If the caps are damaged you will need new ones and the block line-bored to match. Cheaper to buy a 2nd hand block though IMO.

 

It's getting all new clevite bearings and BC rods as part of the build. I will get the caps checked properly as your right there bud but really hoping they are ok

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I would find another engine, but I suppose you might save the head and block, it will need some proper cleaning and measuring though. You need to get ALL the oil gallery plugs out of the block and rifle brush and steam clean with detergent all the oil galleries. The Modine oil / water heat exchanger will be scap, as will any external engine oil cooler. If you reuse any rods they need checking for size and ovality. The oil pump will be scrap, too.

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