Squealing noise around stator and slow return to idles

Brickyard · Post by **Brickyard** » Wed Oct 21, 2015 10:49 am

Thanks, LM.

Can I hot tank dip the crankshaft in caustic chemicals at a machine shop without destroying anything?

LOUD MOUSE · Post by **LOUD MOUSE** » Wed Oct 21, 2015 11:13 am

I use NAPA Carb Cleaner with no problems. .......................lm

Brickyard wrote:Thanks, LM.

Can I hot tank dip the crankshaft in caustic chemicals at a machine shop without destroying anything?

Brickyard · Post by **Brickyard** » Wed Oct 21, 2015 7:38 pm

Well this isn't good. There's no doubt this was a big source of my dry piston problem. Much worse on the right than on the left. Luckily everything on the crank still spins true and free...

Brickyard · Post by **Brickyard** » Wed Oct 21, 2015 7:41 pm

LOUD MOUSE wrote:I use NAPA Carb Cleaner with no problems. .......................lm

Brickyard wrote:Thanks, LM.

Can I hot tank dip the crankshaft in caustic chemicals at a machine shop without destroying anything?

LM, I'm using carb cleaner and an air compressor. Appears to be cleaning the crankshaft ports and gaps just fine with a couple passes of each.

Brickyard · Post by **Brickyard** » Wed Oct 21, 2015 9:48 pm

A job like this was the reason I didn't want to crack the cases. If someone may point me to a link that I can kindergarten, I'd be more than grateful. My quick search wasn't fruitful. The vintagehonda.com parts manual isn't very helpful for more than a few small parts assembly...

And if you happen to know of an "engine rebuild" post, PLEASE post the link! Thanks in advance, BY

Brickyard · Post by **Brickyard** » Wed Oct 21, 2015 9:59 pm

G-Man wrote:Brickyard

That is blocking the splitter which shares the feed from the oil filter to the left hand bearing with the right hand and would account for the lack of lubrication to your right big end and piston.

It looks like general sludge and perhaps parts of your broken-up tensioner wheel. You need to take a careful look at your right hand main and big-end bearings. Run a cleaning brush through the holes at that point and any other. The dirt / debris will have gone further than that plug of material you have in your hand....

What does the inside of the oil filter look like?

G

Brickyard wrote:
G-Man wrote:Brickyard

Those pistons look pretty nasty. The oil ways you show in your video are there to catch oil flowing back down from the top end (cam tunnel) to provide a bit of feed for the main bearings. The main oil source to the main bearings is direct from the oil filter and is related with the oilway you point to at the front of the top crankcase.

I suspect you have debris in your oilways and this debris could be blocking flow into the crank and then up to the cylinder / piston area. The piston / cylinder lubrication comes as oil thrown of the crank / big end.

You really need to strip the motor and clean all those oilways tyou can find as well as cleaning the the centrifugal oil filter and filter screen around the oil pump. If you can, you should get the crank stripped and cleaned, as well, No oil to that piston probably means that the oilways in the crank are blocked.

The debris from the 'dry' piston is going to make the situation worse.

G

Brickyard wrote:Videos will have to do until I can post pictures...

https://www.youtube.com/watch?v=vps9ClM ... e=youtu.be
G, in the area you circled in red, I found what looks to be a gasket or dried gasket maker. Please confirm whats in my hand should be in my hand and not in that area you pointed out...

G, the "sludge gasket" happened to look and feel like a legitimate seal, and I was worried that by pulling it, I'd lose integrity somewhere else.

G-Man · Post by **G-Man** » Thu Oct 22, 2015 1:10 am

Hi Brickyard

You will find that the sludge in this hole will have found its way into the big end bearings and will have reduced the life of your crank somewhat. It is possible to strip and clean this but you do need some tooling. To avoid problems in the future, I think you need to get it properly cleaned and you cannot really do that without taking it apart. You may be able to find a specialist who can do this for you.

The reason that your piston was not being lubricated is because the oil supply to the big-end is blocked by that debris. Beyond the oilway you show in your picture are a whole series of oilways that get oil to the hollow big-end pin.

Take a look at my CB72 restoration thread to see what you are dealing with. The crank may feel OK but I find that difficult to believe judging by the lack of lube at your piston. Sorry to be the bring of doom but now is the time to fix things if you don't want to be doing it again in a few weeks time....

http://www.honda305.com/forums/1961-cb7 ... 1-231.html

Just read on a couple of pages to see where the dirt gets trapped...

G

Brickyard wrote:Well this isn't good. There's no doubt this was a big source of my dry piston problem. Much worse on the right than on the left. Luckily everything on the crank still spins true and free...