[Zeek]

Is this common to the 350's?
Numerous cracks and the top right corner also broken off.
Been toying with removing it and getting it welded, but may be better in the long run to just source a good used bottom case half?

 

[Yendor]

Many of us remove them to get underneath.
It's not hard to drill and tap them studs for bolts.

If it is showing metal fatigue I would get it repaired.
I would not want chunks rattling around in the transmission gears.

 

[longdistancerider]

Remove it, drill a small hole at the end of each crack and get it welded. The hole keeps the crack from travelling any further and also minimizes warpage while welding

 

[Boomer343]

The cracks are typical of high mileage or high rev engines. I've never seen the need to remove the tray, there was a reason Honda choose to rivet it in. One engine I bought had a nasty rattle and it turned out to be a tray that the PO had taken out and then bolted back in.

I also don't think that you will have success with welding unless you are willing to pay a very skilled tig welder. I certainly wouldn't offer any guarantee that there would be even more cracks appearing after welding.

If it was mine and I couldn't find a suitable replacement I would use a silver bearing solder like Stay Brite 8 and Liquid Tec Flux to solder a copper wire over the cracks without removing the tray. You could drill a hole at the end of the crack as well for the soldering but it won't make any difference for welding. Stay brite is far more tolerant of vibrations and far less heat is introduced to the base material compared to welding.

 

[Colorado Pablo]

I just removed this tray from my 2 CB350 engines so that I could make sure that there was no heavy grit or unseen broken parts in there. No parts but it was dirty even after I did what I thought was a good solvent and soapy water rinse. It's quite a maze under there and a couple of "Pockets" required lots of brushing and picking to remove. I'll try to post pic's soon.

I used a Dremel tool to grind off the peened over edge of the 3 stamped "risers" and I feel confident that there is enough remaining that I can re-peen material on top of the riser to secure it when I put it back together.

One of the trays was cracked in several places but the screw heads were also stripped by the last person in there so I'm not sure if the cracks were from normal wear...given the condition and lousy work done I suspect that some of the damage was caused by trying to pry the tray out...he/she was unsucessful.

The other tray looked fine so obviously that's the one I'll be using for the final engine build.

Paul

 

[Boomer343]

I just removed this tray from my 2 CB350 engines so that I could make sure that there was no heavy grit or unseen broken parts in there. No parts but it was dirty even after I did what I thought was a good solvent and soapy water rinse. It's quite a maze under there and a couple of "Pockets" required lots of brushing and picking to remove. I'll try to post pic's soon.

I used a Dremel tool to grind off the peened over edge of the 3 stamped "risers" and I feel confident that there is enough remaining that I can re-peen material on top of the riser to secure it when I put it back together.

One of the trays was cracked in several places but the screw heads were also stripped by the last person in there so I'm not sure if the cracks were from normal wear...given the condition and lousy work done I suspect that some of the damage was caused by trying to pry the tray out...he/she was unsucessful.

The other tray looked fine so obviously that's the one I'll be using for the final engine build.

Paul

Couple points to consider since you have the windage tray out. You will not be able to peen the piece back in place properly. Drill, tap and bolt tightly using red loctite. If you can source a fastener that isn't completely threaded and has a small shoulder that fits tightly into the hole in the windage tray that would be best. Riveted pieces are done that way so there is no movement. Bolted pieces can slip due to the slop in the holes the fastener has to pass through.

It is not industry practice to remove permanently attached pieces unless they are damaged and can be replaced in the same manner as original. I would be a very unhappy customer if a shop removed the tray to clean simply under it. The traps are very effective at holding sludge it is true but removing the tray is not the answer. Any small debris left after cleaning will remain there or float down further to the maze in the bottom of the engine case.

 

[Colorado Pablo]

Well it looks like I've added a drill and tap procedure to this project.

For those that may not have seen under this plate this is what it looks like.

A good 1/4" of sludge under there. This was after I cleaned the case with kerosene and flushed with soapy water.

The other pic is of the cracks I found in one of the plates.

Paul