Squealing noise around stator and slow return to idles

[Brickyard]

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

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...

G, im not going to go that route. I know its the right thing to do, but I dont have the tools I need to do it myself, or the $ for someone else to do it. My goal is to fix the dry piston, replace other worn parts, and move on. I'd like to think that any left over debris i couldnt get with carb cleaner and air is small and will be suspended in oil that now has new ports to flow through.

Im definitely taking advantage of your build in order to put my engine back together the right way!

[G-Man]

Hi Brickyard

I completely understand your situation. I thought of a simple check you could do to make sure you are getting oil to the big-ends (and from there the pistons).

Lay the crank in the upper crankcase (upside down) with the rods hanging downwards. Inject some light oil or solvent in the back or front lube holes in the main bearing (not the middle one) next to the lower of the two conrods.

Then, watch for oil coming out the sides of the conrod on that side.



You should see it running out of the rod sides and the slot pointing towards the small ends.

You can compare how much comes through left and right rods to see any difference.

Good luck.

G

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

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...

G, im not going to go that route. I know its the right thing to do, but I dont have the tools I need to do it myself, or the $ for someone else to do it. My goal is to fix the dry piston, replace other worn parts, and move on. I'd like to think that any left over debris i couldnt get with carb cleaner and air is small and will be suspended in oil that now has new ports to flow through.

Im definitely taking advantage of your build in order to put my engine back together the right way!

[Brickyard]

Will do, as soon as i clean the case surfaces of old hondabond. Maybe tonight or tomorrow. I thought the hot tank would have done that, guess not.

Hi Brickyard

I completely understand your situation. I thought of a simple check you could do to make sure you are getting oil to the big-ends (and from there the pistons).

Lay the crank in the upper crankcase (upside down) with the rods hanging downwards. Inject some light oil or solvent in the back or front lube holes in the main bearing (not the middle one) next to the lower of the two conrods.

Then, watch for oil coming out the sides of the conrod on that side.



You should see it running out of the rod sides and the slot pointing towards the small ends.

You can compare how much comes through left and right rods to see any difference.

Good luck.

G

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

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...

G, im not going to go that route. I know its the right thing to do, but I dont have the tools I need to do it myself, or the $ for someone else to do it. My goal is to fix the dry piston, replace other worn parts, and move on. I'd like to think that any left over debris i couldnt get with carb cleaner and air is small and will be suspended in oil that now has new ports to flow through.

Im definitely taking advantage of your build in order to put my engine back together the right way!

[Brickyard]

Im having a difficult time deciphering the vintagehonda parts manual to find out where dowel pins and knock pins go in the cases. I've found a couple based on other peoples builds. Will someone be so kind to point them out for me? Thanks in advance!

[Brickyard]

I believe all of my dowel, knock or whatever you call them pins are good to go, since I dont have any left. One is out of the ordinary (is solid and has a raised tip), but comparing it to my crankshaft bearings, it makes sense.

If someone can confirm there arent any missing, that would be awesome!

[Brickyard]

G, I just confirmed that both rods were getting lubrication after squeezing light oil into both the forward and aft lube holes.

Hi Brickyard

I completely understand your situation. I thought of a simple check you could do to make sure you are getting oil to the big-ends (and from there the pistons).

Lay the crank in the upper crankcase (upside down) with the rods hanging downwards. Inject some light oil or solvent in the back or front lube holes in the main bearing (not the middle one) next to the lower of the two conrods.

Then, watch for oil coming out the sides of the conrod on that side.



You should see it running out of the rod sides and the slot pointing towards the small ends.

You can compare how much comes through left and right rods to see any difference.

Good luck.

G

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

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...

G, im not going to go that route. I know its the right thing to do, but I dont have the tools I need to do it myself, or the $ for someone else to do it. My goal is to fix the dry piston, replace other worn parts, and move on. I'd like to think that any left over debris i couldnt get with carb cleaner and air is small and will be suspended in oil that now has new ports to flow through.

Im definitely taking advantage of your build in order to put my engine back together the right way!

[LOUD MOUSE]

Ya have all the pins in the proper locations.
Inside of piston Looks Like It Had Plenty/Sufficient Oil. ..............lm

G, I just confirmed that both rods were getting lubrication after squeezing light oil into both the forward and aft lube holes.