good to know on that airflow to #4, i'll have to remember to inspect my cooling. Sounds like a good assessment, lack of air, lack of heat pulling oil flow, toss in some iffy gas and that's more than enuff.
Its finally alive again!
It looks old on the outside but its all new on the inside. Bored out to 40 thou oversize, new pistons, rings, shells, valve guides, and numerous other bits and pieces. I finally got her started today and it sounded pretty good considering it has no muffler. I only ran it for a minute or two as I have no cooling tinware attached. (In fact I am missing a few bits that I have to fabricate).
I should have taken a pic of all the plastic bags I had parts in. I had about 25 of them and I labelled everything as i removed it, no matter how 'obvious' it was. I thoroughly recommend you do this if you are planning a job like this. When an engine has been in pieces for 6 months its easy to forget what things are for. Especially all the various bolts.
I had to drill and fit helicoil threads for about 8 of the head bolts, so if anyone wants to know about that, now's the time to ask.
One last minute problem I had was with the starter. It 'sounded' like the starter was spinning without the pinion engaging. But in fact the pinion WAS engaging but it was jamming against far end of the starter housing causing the ring gear to lock solid while the starter shaft kept rotating. Its a bit hard to explain, but a few extra washers in the right place and some grease seems to have fixed it.
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I've mentioned previously how skeptical I am about the lubrication system on these things. Well after having totally dismantled, then rebuilt it, I am now even more dubious. So much so that I have added additional oil lines to the top of the engine to use as a pre-oiling system prior to start-up. You can see in the pic below the braided lines running into each of the 4 valve chambers. For now I am simply using an oil can to pump oil into the hose. From there the oil drips down directly onto the crank shaft where it will be thrown around with the first rotation of the crank and will lubricate the cylinder bores and cam much quicker than waiting for the internal system to do its job. When the engine is installed I'll be adding either an electric or hand pump to circulate oil from the sump for a minute or two prior to start-up. One thing I discovered while prepping the engine is that the oiling system simply does not work satisfactorily at 'cranking' speed. Theres just not enough pressure being developed to spray oil via the internal jets. At cranking speed it simply dribbles out. So, if you are cranking a hard starting engine, its basically running 'dry' unless its been used regularly and thers a residual film of oil on everything.
This also means that the oil filter takes a long time to fill up and provide back pressure. So if you rebuild one of these donks and fit a new filter its a really, really good idea to pre-fill the oil filter. And of course make sure you oil everything really well as you assemble it. I used 90 weight gear oil on most things.
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Finally, in case anyone is wondering, these pics have been inserted using 'Imgur'. (Google it). I wish I had discovered it earlier. Its free and only takes about 5 seconds to upload and link a picture. You just drop your pic into a box, wait a few seconds than click the 'Embed' tag and copy and paste it. Its far, far easier than Photobucket - who now want to charge a bundle!
