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TLicense Engine Build


TLicense
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After stalling on my original intention to rebuild my engine earlier this year, and being far too busy during the racing season, I'm finally able to crack on with building my engine.

 

I've stripped the engine, and will do a write up on how to do that soon and link it into this thread.

 

But anyway, after stripping the block, it was clear to see as I suspected, that it had suffered from bore wash. The cylinder bores had absolutely no evidence of any of the hone marks and the bores were heavily worn, this led to poor combustion chamber sealing and poor compression.

 

So I took the cylinder block to my local machine shop and got them to clean, bore the block out to 86.5mm and to give it a hone. In order to hone the cylinder block, it's necessary to supply the machine shop with the pistons that will be used so they can measure the diameter and machine the block to suit. I got them also to label up the pistons so I knew which bore each piston was measured for.

I also got them to do a few other bits and bobs that I'll cover when I get to them.

 

Upon return of the cylinder block, I re-measured it all. I'm using CP pistons which specify a bore diameter of 86.512mm (3.406") +/- 0.005 (0.0002"). The cylinder bores should be measured 10mm from the top of the bore, the middle of the bore and 10mm from the bottom of the bore, axially and radially to the crankshaft.

Here's a pic of the bores being measured prior to machining (I forgot to take some afterwards!):-

 

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The maximum dimension I found was 86.517mm (3.4062") and the minimum was 86.507mm (3.5058") so just within tolerance.

 

If they're all within tolerance, then the next thing to check is the flatness of the mating face. This needs to be done along all four edges of the cylinder block and from corner to corner. Use a feeler gauge to find what the maximum distortion is. If it's any greater than 0.07mm then you need to skim the head. The most mine was, was 0.05mm. (Note my straight edge isn't quite long enough so I needed to measure in lots of steps to check

 

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Here you can see the gap you're trying to measure:-

 

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That pretty much sums up the cylinder block checks (other than crack testing, but I'll not be going into that here). Tomorrow I'll go through the crankshaft and the main and thrust bearings. :)

Edited by TLicense (see edit history)
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I wouldn't like to write anything libellous by saying "poor mapping". Let's just say it running extremely rich due to some mistakes. Some of them corrected by the mapper when pointed out by myself, others corrected by Ryan when he got his hands on it. Unfortunately the damage had already been done...

 

I'll let you draw your own conclusions to that. ;)

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I wouldn't like to write anything libellous by saying "poor mapping". Let's just say it running extremely rich due to some mistakes. Some of them corrected by the mapper when pointed out by myself, others corrected by Ryan when he got his hands on it. Unfortunately the damage had already been done...

 

I'm hearing you on FM :D

 

Look forward to the thread mate :)

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Today I checked out the crankshaft.

 

First of all I measured the crankshaft runout. Ideally this would be done by setting the crankshaft on a pair of v-blocks. However as I don't have suitable blocks, so a perfectly fine alternative is to sti the crankshaft back into the cylinder block.

Using a DTI you want to measure the no.4 crankshaft journal. The maximum runout is 0.06mm. The runout on my crank was less than a 10th of that.:-

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Next remove the crankshaft and set it down on a clean surface. Using a micrometer, you want to measure all of the journals. You want to measure the journal in at least two positions 90 degrees to each other, at both the front and back of the journal. (I measured at 45 degrees and front, middle and back just to be sure!) It should measure between 61.984mm and 62.000mm. The biggest difference you should see from the front to the rear (taper) of any journal should be 0.02mm. Make sure that you measure opposing sides of the journal. It's quite easy to not measure completely accross the journal. The min I measured was 61.9855mm and the max was 61.988mm. The biggest difference in taper I measured was 0.004mm.

 

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Once you've measured the main journals do the same for the crank journals. The tolerances here are 51.982mm to 52.000mm and again 0.02mm of taper. I measured a min of 51.9835mm and a max of 51.990mm. The largest taper was 0.003mm.

 

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If you've measured all that, and there are no scores or burs on the journals, then the crankshaft is good to go!

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I next checked the main journal oil clearances.

Having measured the crankshaft journals, it's possible to measure the main bearings housings with the bore gauge and calculate what size bearings to use to give you a nominal oil clearance. I was going to use Power Enterprise bearings, however after finding supply issues in the UK, I decided to go with stock Toyota bearings shells.

Toyota supply 5 different sized bearings ranging from 1.994mm to 2.009mm thick.

Calculating which ones to use is a fairly simple affair. You measure the cylinder block main bore then subtract the diameter of the crankshaft journal and divide the answer by two. This gives you the bearing clearance plus the oil clearance. The tolerance on the oil clearance is 0.026mm to 0.040mm. I'm going to target an oil clearance midway between the two so 0.033mm. Divide this by two and subtract this from the answer you got previously. This will give you the bearing size you need.

 

For example, the no.1 cylinder block bore on my block is 66.031mm. The no.1 crankshaft journal is 61.987mm. So the bearing + oil clearance size is 2.022.

Divide 0.033 by 2 which is 0.0165, and subtract this from 2.022 which is 2.0055mm.

 

Toyota's range of bearings are:-

 

Mark "1" = 1.994 - 1.997mm

Mark "2" = 1.996 - 2.000mm

Mark "3" = 2.000 - 2.003mm

Mark "4" = 2.003 - 2.006mm

Mark "5" = 2.006 - 2.009mm

 

So you choose the bearing "mark" that the size you measured fits into. So in the case of my no.1 bearing I need a mark "4".

Easy! :D

 

If not, Toyota supply an alternative method of calculating the bearing thicknesses based on what they measured the crankhaft journals and cylinder block bores when they were made. There are numbers stamped on both crank and cylinder block that indicate what they measured. However I prefer not to rely on someone else's work, and you never know if the block / crank have worn over time. As it turned out, my crank and cylinder block still fell within the sizes as it came out of the factory 100000 miles ago!

If anyone would like more details on how to use the Toyota system then pm me and I'll send details (it's involves creating a table in excel)

 

When you go to order your bearings up. There's one last thing to be aware of. The no.1 journal bearing is not the same as all the rest. It's 23mm wide and has the locating tab towards the rear of the journal:-

 

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Whereas the rest are 20mm and have the tab towards the front:-

 

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One you've got the bearings, it's a good idea to double check your oil clearances. I did this by using "Plastigage" which if you do a search on google you'll find a supplier.

 

To do this clean all the cylinder bearing faces, and when I say clean, I mean really clean. You want it to be spotless. Then fit all the bearings you've bought. Note that bearings have the mark no. or size stamped into them:-

 

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Ensure that you fit the right size bearings into the right journal.

Also note that the upper bearing shells have a slot in them whilst the lowers do not. I also made sure that I would keep the uppers and lowers as pairs and not mixed them up by keeping the lowers in their boxes until I needed them and labelled up the boxes with which journal I was going to fit them into.

Here's all the bearing upper shells fitted:-

 

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Next carefully place the crankshaft back onto the bearings. Be careful the bearings are pretty soft and will get burrs on them pretty easily.:-

 

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Next place a small strip of plastigage onto the crankshaft journal. It's the small line going across the journal in this pic!:-

 

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I then fitted the lower bearing to the main cap for that journal:-

 

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I then loosely fitted that main cap to ensure the plastigage didn't get knocked off. When fitting the main cap note that each cap has the no. of the journal it came from stamped on it, as well as an arrow pointing towards the front of the engine. Ensure you fit the correct main cap and that it is in the correct orientation:-

 

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Do the same for all of the journals, but make sure you don't rotate the crankshaft otherwise it will smear the plastigage:-

 

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Now you need to torque all of the bolts in order. It's a bit tricky to explain in words the order, but you start with doing both bolts on the no. 4 journal, then the no.3, no.5, no.2, no.6, no.1, and lastly no. 7. To help make sure I didn't get confused, I wrote the order on the bottom of the block:-

 

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I did mine up to 20Nm, then up to 44Nm. To help you get the 44Nm on an engine stand a tip is to rotate the engine so that it is on it's side.

After doing them up to 44Nm, you then turn them an extra 90 degrees. To help make sure I turned them 90 degrees, I marked the bolt heads with a dab of paint on one edge (I marked mine at the top). Then when I torqued the bolts, I just had to make sure the paint marks were pointing towards the front. Easy! :)

 

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The next job is to now undo all the lovely work you've done. Remove all of the bearing caps in the reverse order (working from the front / rear to the centre). Undo them in steps, by undoing them all by just 90 degrees and then undoing them so that they're loose. Remove all the bearing caps and you should see that the plastigage has squidged and left a smudge on the bearing and the crankshaft:-

 

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Using the gauge paper that comes with the plastigage hold it up to the smudge and you should be able to measure off the oil clearance that you'll end up with! :)

 

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Remember you want to end up with between 0.026mm and 0.040mm.

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OK, so you've ordered the correct bearings now, there's one last thing to check. The crankshaft thrust clearance. This is how much movement the crankshaft has forward and rearward. This is controlled by the thrust washers, which on the sides of the no.4 journal web and main cap.

Here you can see the one at the front:-

 

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and the rear:-

 

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Ensure you get the orientation of them correct and that the grooves are on the outside.

 

Fit the lower halves to the main cap:-

 

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Now fit all the bearings caps once again using the method above.

Once they're all done up, fit a dial gauge so that axial movement on the crank nose:-

 

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Then using a screw driver, gently lever the crankshaft forward and rearward and note how much travel there is:-

 

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There should be between 0.020mm and 0.220mm. Mine was 0.067.

 

And that is the main bearings pretty much sorted.

I'm not going to be able to post for the next couple of days but on Thursday I'll go through assembling the rotating and reciprocating assemblies ready for it to be sent off to be balanced.

 

Oh one last thing, a simple way of making sure that you don't get crud onto your engine whilst your not working on it, is to simply stick it in a black bin bag.:-

 

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Edited by TLicense (see edit history)
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This is a great writeup, alas it goes way over my head!

 

Many thanks for the compliments guys. :)

 

If there's any particular bits that you're interested in, or are unsure of, shout out and I'll try to explain it better or will take more pics of. It's a lot easier to do it now than when it's all put back together! :D

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whats your thoughts on honing with a torque plate Tony, reading this thread http://www.mkivsupra.net/vbb/showthread.php?t=129726&highlight=deck+plate seems to indicate for a road car and the heavy duty nature of the block not to bother, just wondering if your measurements back this up, i am also really jealous of your measuring equipment :D at my old company we had all this gear, i should have "liberated" some when i left

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whats your thoughts on honing with a torque plate Tony, reading this thread http://www.mkivsupra.net/vbb/showthread.php?t=129726&highlight=deck+plate seems to indicate for a road car and the heavy duty nature of the block not to bother, just wondering if your measurements back this up, i am also really jealous of your measuring equipment :D at my old company we had all this gear, i should have "liberated" some when i left

 

I designed and machined a torque plate for the machine shop I used for when they bored the block. I spoke to them afterwards and they said that they had used it, but in their opinion it wouldn't have made any difference. They said that it was the first time they'd seen one being used in a very long time.

Personally, I think if you can get hold of one or make one of your own for relatively little hassle, then it's not going to do any harm.

If anyone wants a drawing of a torque plate that will fit the 2JZ-GTE, send me a pm with your e-mail address and I'll forward it onto you.

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I designed and machined a torque plate for the machine shop I used for when they bored the block. I spoke to them afterwards and they said that they had used it, but in their opinion it wouldn't have made any difference. They said that it was the first time they'd seen one being used in a very long time.

Personally, I think if you can get hold of one or make one of your own for relatively little hassle, then it's not going to do any harm.

If anyone wants a drawing of a torque plate that will fit the 2JZ-GTE, send me a pm with your e-mail address and I'll forward it onto you.

 

cheers Tony thats great real world advise :salute:

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