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View Full Version : one of my rod bolts came into contact with my crankshaft...



newaccorddriver
04-15-2007, 10:15 PM
like the topic says...:gun:

i put the new piston into the bore, and since my compressor was hitting a stud, it was hit in a slight bit sideways. stupid me, i forgot to turn the crankshaft to BDC and then pull the piston to the journal, instead, the piston went down, and hit the crank and then centered itself onto it. i inspected the crankshaft itself several times, and it didnt look like i did anything to it, nor did my friend see anything out of the ordinary. is this something i should worry about?


id hate to see a bearing get chewed up because of it, and id hate to rip everything apart just to check over it again.

newaccorddriver
04-15-2007, 11:20 PM
wow, what a gong show. somehow 2 of my rod journals had scratches on them. good thing i took it apart to check it out otherwise...:violin:

not a clue how those 2 scratches got there since my hands were clean the entire time and such and such. the worst part is i can kinda feel them with my nail(despite almost having none)... im not sure what other options i have right now other then polishing it which isnt recommended, and replacing it, which is kinda impractical... man im pissed.

im gonna get the machine shop to check it out and see what they can do since this is BS. their import gurus, so im gonna give them a shot at fixing this problem i have...

cygnus x-1
04-16-2007, 10:32 AM
Wait, didn't you just say that one of the rod bolts hit the crank? Might that have caused the scratches?

If you can feel the scratches then they're pretty big. Although it might still be salvageable. See what the shop says.

C|

rjudgey
04-16-2007, 11:49 AM
crank journals need to be perfect, you might be able to have it polished out if it's just surface scratch if it's deeper you'll have to have it re-ground as long as it's not been done before then have oversized bearings put in. I once had a bearing knock itself out from oil starvation replaced the bearing and got a strip of wet and dry folded it to the same width as the journal wrapped it round and sanded it smooth this lasted all of about 1000miles before it were fooked again surprised it lasted that long ;0) was only a temp fix honest!! Just last long enough for me to build the spare block i had!!! Anoying thing was this engien had only done 500miles before this happened and before that the engine had only done 500 miles as well becuase an engineer over heated the rod which caused the pin to come out and damage the bore really badly. Just really kick me self as the total seal rings were $300 and i though i could get away with using them again but it was brunign too much oil and on a long trip it had drunk 4 litres of oil in 200miles and then the bearing went!! Engine ran for 50 miles without a bearing after putting some oil in was quite amazing obviosuly was driving real slow!!!

88Accord-DX
04-16-2007, 04:09 PM
Next time you install the rod at BTDC, put some vacuum line or rubber hose over the studs (about 1/2 past the end) before you install them. Your on the right track with having the machine shop look at it. There are ways to get by, but I'm not recommending it.

88Accord-DX
04-16-2007, 04:09 PM
double post, dooh!

AccordEpicenter
04-16-2007, 04:20 PM
Next time you install the rod at BTDC, put some vacuum line or rubber hose over the studs (about 1/2 past the end) before you install them. Your on the right track with having the machine shop look at it. There are ways to get by, but I'm not recommending it.

I reccomend this also. Dont risk having the engine get fucked up with scratched journals, have a machinist look at it

newaccorddriver
04-17-2007, 12:34 AM
i actually had vacuum hoses bought for this purpose, but i dont know where they went at the time.

on a side note, i took my crank to the machine shop and let the guy with 40 years of experience look at it. he just looked at the scratches i had, and laughed at them. apparently they were nothing to worry around since he normally rebuilds engines with those kinda scratches on it. reason being that the crank itself never touches the bearing, and nothing was 'sticking out' of the area of the scratches. basically he said that that area fills up with a bit more oil and just lubricates it more. he even told me stories about how datsun cranks were garbage from the start since they werent hardened, but the lubricating system that datsun had at the time, was what made the engines last so long.

cygnus x-1
04-17-2007, 09:55 AM
He is correct in that small depressions aren't a problem. What you don't want are burrs that are above the surrounding surface.

C|

AccordEpicenter
04-17-2007, 06:18 PM
He is correct in that small depressions aren't a problem. What you don't want are burrs that are above the surrounding surface.

C|

exactly, on some knicks and scratches it might make the metal raised above the rest of the journal and thats what tears up bearings

88Accord-DX
04-17-2007, 07:16 PM
Uhh, nevermind.

newaccorddriver
04-19-2007, 11:31 AM
exactly, on some knicks and scratches it might make the metal raised above the rest of the journal and thats what tears up bearings


i just installed the rod on the journal in question. what i did was spin it around a bit, and took the bearing out and checked for signs of damage to the bearing surface. there was none on the bearing surface. i should be fine now right?