Rod Cap Backwards, Crank ok?

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Newfie_Sol

Newfie_Sol

New Member
So who ever built the motor before I bought the car put a rod cap on backwards... has anyone had experience with this on a b16a3..

I've been asking local shops and people about this and 50% say that its fine.. just rebuild the motor with the rod cap installed correctly.. and the other 50% say that my crank is out of spec and my rod is ruined and to have them both re sized...

any help would be great...
 
the rod is probably not ruined but it will need to be resized to true roundness again cause the idiots that did that messed up the oil flow on that rod. the cap has a notch and the rod does also, they have to go on the same side otherwise a spun bearing is bound to happen.
is it making any noise? do you have it apart? how does the bearing look?
hope its all good.
 
I've got it apart.. here are the rod and journal..

sorry they are a little blurry.. :imfucktard: with cameras.. if you need to see them in better detail I can take it apart tomorrow in the light and get some more detail..

In the picture of the rod - You cannot feel any of the marks that you see running up and down...

I'm told they are chatter marks and tend to a "bad" sign and could possibly mean that my crank is spoiled as well?:confused:

On a side note - in the second pic.. which marking is it on the left that tells me the size of the rod journal on the crank? A "B" on top and possibly a "4" or an "A" on bottom?

Thank you for sharing your knowledge and experience
 

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is that the bearing or the actual rod?
that crank needs to be taken to a machine shop, they will let you know if a micropolish is all thats necessary or if its worse than it seems.
And on the second pic, it will be the 'B' along with the number thats stamped on the rod (half on the rod and half on the cap)... those two together will let you know which bearing you need, as long as the rod has never been machined cause they were out of round.
 
Its the bearing in the rod that your looking at.. I'll take it out and take a better pic of it..

Why would you want to bring that crank to a machine shop? What is it in the pic of the journal that makes you weary about the crank?
 
I would not have worried about them.. they are not horizontal like chatter marks..
 
In the picture of the journal, you are not able to catch a nail on any of the small lines you see running with the bearing...

My main question was a definite yes or possible no to the crank being spoiled by a single rod cap being put on backwards on a b16? Anyone have any experience to share?
 
no its not completely trashed, you have to take it to the machine shop to make sure of it.
 
you couldve, shouldve, normally wouldve had a serious problem.
im kinda surprised the car even started like that(assuming that youve driven it since you bought it.)
 
oyy0
no its not completely trashed, you have to take it to the machine shop to make sure of it.
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I checked in the Del Sol service manual for the inspection process. Honda says to check the journal on the X and Y axis.. so I busted out a lucky set of Vernier Caliper's and went nuts.. I forget the tolerances.. but I can get a couple pics of the manual.. mine was well with in the limits

MthaFuknGreen
you couldve, shouldve, normally wouldve had a serious problem.
im kinda surprised the car even started like that(assuming that youve driven it since you bought it.)
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When I realized that the cap was on backwards I thought I was up the creek without a paddle. I went to a school where I live, they teach an accredited Aircraft Maintenance Engineering program there.. I spoke to some of the AME's who teaches overhaul courses etc.. we took some measurements and the rod seems ok.. and the crank has no odd wear so I'm just going to throw it back together and see what happens..

The AME showed me a cool trick to micro polish a crank field strip style with some 1000 grit wet dry sandpaper and a rope! Saves me a dollar!
 
i was about to tell you to take a micrometer to that bitch and make sure everythings still in spec before assuming the worst. you got lucky though, a piston couldve seized and fucked a bunch of shit up.
were the rod diameter and bearing size too big for the crank journals? cuz the only way i could see your engine surviving is by having enough clearance to make up for the misfit.
 
Newfie_Sol said:
In the picture of the journal, you are not able to catch a nail on any of the small lines you see running with the bearing...
Click to expand...
use a penny instead of a nail...its more precise..if any copper rubs off the penny onto the scores then there is a problem
 
I ment finger.. nail.. like on your hands.. :) I'll take it a step further.. I read in an overhaul manual to lick all the scratches on the journal... as your tongue is a very sensitive organ for this task.. just be sure to lube the journal with some WD40 prior to tongue check... this is very accurate in conjunction with bubble tape..
 
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MthaFuknGreen
were the rod diameter and bearing size too big for the crank journals? cuz the only way i could see your engine surviving is by having enough clearance to make up for the misfit.
Click to expand...
I have a #1 rods and a B crank journal.. I believe comes up as a Pink bearing?? what I took out of it was a King bearing, standard.. which is a green?? I have no clue on that one actually..

So the bearings were not sized correctly.. assuming that the King bearing standard is actually a Green Honda OEM...

If you take the rod and put the cap on backwards the Center of the rod big end is actually in the same place... but the rod bolts are not centered on the rod.
If you were looking at it from the numbered side... they are off center by very little. With the cap on correctly you cannot catch the lip where the cap and rod joins along the face of the rod.
With it installed incorrectly you can catch your finger nail on the join one way and not the other.. and on the opposite side of the rod it happens in the other direction...

Soo... if you laid your rod on the table in front of you and installed the rod cap on backwards in the X and Y axis the rod is fine.. but in the Z axis it is not.. so it did not effect the timing..

at least this is what one of these soo called aircraft maintenance guys explained to me.. so I reserve the right to withdraw this statement if someone has proof otherwise :thumbsup:
 
but do you see how the tangs are placed when you do that?
how do you suppose there will be good oil lubrication with the tangs on opposite sides?
if you really don't see any serious problems, then truly you are lucky and do what you need to do to get it running.
and you are right, the king bearings are all green.
just make sure you are within clearance tolerances and you should be fine.
 
I always understood the tangs to stop bearings from spinning as they are recessed in the rod as well, and not affect oil flow... now, I'm by no means an engineer but the purpose of oil in a bearing is to remain flat and uniform across the whole journal..

How does a tang help with oil flow remaining stable in the bearing?
 
it doesn't, they are simply there to hold the bearing in place within the rod journal.
 
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