Originally Posted by E26-2
will run at that low of a compression
. . Check the rod .make sure it's not bent .
<sigh> back to step -5 it appears.
So we got the compression up to 375psi with some oil
(see previous posts) and got some compression sealer gloop that we hoped would sort that out until the new rings were bedded in.
But before it arrived...
stopped. One of the nuts fell off the big end bearing cap; the thread was completely stripped by the time it had finished; the other bolt was bent at 45 degrees. The shells were mashed. In the process of getting a big dent, (and distorting the big end shell socket so that between-centres was 10mm less than the end cap) the connecting rod smacked a chunk out of the bore (but fortunately below the oil
scraper) ... miracle it didn't go through the side of the crank case. Oh and the big end journal had a couple of 500um dents in it.
So my first mistake was not making sure that when he fitted the new bearing shells that (a) he had inspected and measured the journal and (b) used a torque wrench on the nuts..
But we found out some other things at the same time...
1. The big end journal was not so much -500 undersize as -2000 undersize - god knows where those shells came from - so when he fitted true-size shells it was clattering around like hell - not surprising there was so much vibration :/
2. Volvo Penta
was the reincarnation of Bollinder. Big respect. The Penta
2001 was known as the "Baby Bollinder". One supplier said "when these came out we thought that they wouldnt last very long - but 35 years later and they are, only now, being retired; Bollinders are basically bulletproof so it looks like these were as well". Interesting...
3. You would not believe how hard it is to find parts
but (if anyone doesn't know) this is useful:
(select your country obvs)
4. You can build up a mashed journal with weld and get an engineering shop to grind it back. But they need to be one with an offset crank grinder and a dimension to work
with - if the journal is filled up with weld then the datum axis is lost
; this is a calibrated offset from the shaft axis. Whatever that number is... (out of the data book actually).
And TIG is better for building up. No valleys. And watch for warping.
But this approach means that you can go back to true size and from then on everything else is peachy. Maybe.
New shaft? From the US? $1600 and $75 shipping
We found one engineering shop that we thought could do the journal. "How big"? "52" "Oh that's a bit small - we can't go down much below 100... Did you say it was a bulldozer or a train?"
5. A new engine
might have been a good idea if we found one at the beginning.
Never a dull moment.