The short story - I bought used D16Z2 block,but unfortunately I didn't have the time to check it out properly - so when I removed crank, I found some metal debris in oil pump pickup and worn out bearings - it seems that engine it suffered from lack of lubrication, but visually, crank journals looked relatively good, without some serious/deep scratch marks.


OK, I hoped that clearances were at least close to service limit but when I measured them, they were soooo far away from what I expected that I just have to put here for my sanity check:

1. Main bearing clearances (measured with dial bore gauge, ACL race std bearings):

1st bearing : 0.0043" (0.11 mm)

2nd bearing : 0.0036" (0.092 mm)

3rd bearing : 0.0041" (0.105 mm)

4th bearing : 0.0041" (0.105 mm)

5th bearing : 0.0045" (0.115 mm)


2. Rod end bearing clearances (measured with dial bore gauge, ACL race std bearings):

1st bearing : 0.0040" (0.10 mm)

2nd bearing : 0.0036" (0.092 mm)

3rd bearing : 0.0039" (0.92 mm)

4th bearing : 0.0038" (0.97 mm)


Then I thought that something is seriously wrong so I verified again clearances but with green plastigage and I've got this:

- all measured clearances were more then 0.0029" (thinnest line on plastigage scale) and were just a little tighter then dial bore gauge method but again TWICE larger then service limit in my Honda manual :shock:

OK, then I measured crank journals and main journal diameters were like this:

1. Main bearing journals (measured in 4-points with 0.0001" micrometer, then averaged):

1st bearing : 2.1646" (54.98 mm)

2nd bearing : 2.1648" (54.99 mm)

3rd bearing : 2.1645" (54.97 mm)

4th bearing : 2.1645" (54.97 mm)

5th bearing : 2.1648" (54.99 mm)


2. Rod end bearing journals (measured in 4-points with 0.0001" micrometer, then averaged):

1st bearing : 1.7709" (44.98 mm)

2nd bearing : 1.7710" (44.99 mm)

3rd bearing : 1.7708" (44.97 mm)

4th bearing : 1.7709" (44.98 mm)

I will probably buy another D16 crank, but I do have few questions:

Has someone measured used crank journal diameters so I can check it just for comparison ?

Has anyone measured such large clearances on used crank before?

First I thought that I didn't measured something very well with micrometer & dial gauge, but even with plastigauge clearances were almost twice the service limit.

 

journal od's are listed in the service manual.

 

2 IN VTEC:

Of course, I already checked service manual ...and I checked official ACL webpage...and according to this link for ACL race bearing application:

http://www.aclperformance.com.au/HondaD16ZCBearings.htm

...some of my crank journals would still satisfy "Min Std Shaft Size" condition , but clearances are telling totally different story, so I am still confused.

Is it possible that main bearing bores of this engine block & Eagle rod bores combination is so totally off, that in combination with this particular crank can produce such large clearances?

 

so you figured this all out by math correct? Did you divide you clearence number by 2? I did not do this once and almost SH%T myself after spending $900 on machine work back in my hay day. I had readings of .0030. then realized I was right at .0015 like I should have been. Just a thought Or that motor is wasted
Nick

 

Not only by math - if you read again carefuly, I've doubled checked everything with green Plastigage, just so I can be sure that my math isn't totally wrong...and Plastigage showed similar results and correct calculations.


To make it more clear, I used this simple method for measuring bearing clearances (in fact, there's almost no math involved):


1. First I used suitable micrometers to measure both rod & main journals,


2. Then I locked micrometers so I can use freshly measured rod/main journal diameter as a reference,


3. I then placed new ACL race bearing halves in main bearing/ rod end bores,


2. Then I torqued main/rod bearing caps to correct torque,


3. After that, I used digital bore gauge, placed inside micrometer jaws and set dial indicator to zero.


Zero at dial gauge is now equal to rod/main bearing journal diameter.


4. Now I placed my bore gauge inside bearing halves within main/rod end bores...this way, I can read any deviation from this reference gauge as bearing clearance directly.


Maybe this isn't the best way, but I tried to avoid usual stack-up error if I measured bore diameter first, then diameter journal, then bearing thickness and all that put in calculation.

Not to mention that if I used micrometer only as a reference tool for my dial gauge, that way I am avoiding all eventual reading errors.