Topic: 1972 oil pump question

[maestro]

I have a 72 cb750. I am having oil not staying in the tank after sitting. I bought the seal and spring kit. Today I started replacing those. Upon going for the inner shaft seal I have 2 issues. One the inner shafte seal is not coming out. Is there a good technique for getting the metal sleeve out? The other issue, which may nullify the first issue, there is some scarring where the pump rotors sit. Is this enough to where I need to replace the pump?

[Trav-i]

I completed this exact project about 2 weeks ago.  I had the same issue getting the seal out.  After several hours of working and getting no where, I went for broke and got it out.  What I used was the straight pointed pick from my pick set.  I got it positioned between the seal and pump body and drove it in till the old seal buckled.  It was a real nail biter I was worried I'd damage the housing but, thankfully it came out ok.  Once the seal buckled I pulled it out with the 90 degree pick.  The shaft seal I used was an actual Honda seal, per Hondaman's recomendation.  I used either a 10 or 11 mil socket with extension to drive it in.  I would use some green scotchbrite to clean up the scratches.

Hope this helps,

Travis

[MauiK3]

I have not checked recently but I think Hondaman’s book has the housing condition information you need. His book is a must have item for these bikes.

[HondaMan]

I completed this exact project about 2 weeks ago.  I had the same issue getting the seal out.  After several hours of working and getting no where, I went for broke and got it out.  What I used was the straight pointed pick from my pick set.  I got it positioned between the seal and pump body and drove it in till the old seal buckled.  It was a real nail biter I was worried I'd damage the housing but, thankfully it came out ok.  Once the seal buckled I pulled it out with the 90 degree pick.  The shaft seal I used was an actual Honda seal, per Hondaman's recomendation.  I used either a 10 or 11 mil socket with extension to drive it in.  I would use some green scotchbrite to clean up the scratches.

Hope this helps,

Travis

This is similar to how I do them. I have also drilled a (tiny, like #38 drill) hole alongside the edge of the seal's metal outer ring, then bent that metal inward far enough to drill another tiny hole thru it and pop it out by folding the seal in on itself with a sharp pick into that hole. Don't drill so far down that you go into the wall between the 2 chambers, just 1/2 to 2/3 of the way down the side of the seal ring is enough.

If you have a collection of sharp, new taps you can also find one (11mm? Forgot the size) that will let you grip the metal ring, after stripping out the rubber stuff, and tug it out. A nice, clean way, but not everyone has taps lying around.

[Nurse Julie]

Use a tap to remove the seal.
http://forums.sohc4.net/index.php/topic,175754.msg2045266.html#msg2045266

[maestro]

Good tips. I didn't see this first. I ended up using another user's method. I bought a blind bearing puller and a Dremell 199 cutter and got it out. I ended up not using the puller. When I went to cut the groove to catch it the bearing snagged on the cutter and spun right out. Here are links to what I bought.

https://www.amazon.com/gp/product/B00004UDGP/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

https://www.amazon.com/gp/product/B06ZZ2FPVQ/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1