Topic: 79 CB650 Oil FilterBolt Size

[donaldb]

My son is in school 1200 miles away and it looks as though he has stripped the oil filter bolt threads.  I'm trying to find out what the size of the bolt is, he thinks it M19 X 1.5 but that's pretty odd size so I figure it M18 or M20.  Any info would be greatly appreciated.

donald

[bryanj]

If he has stripped the thread in the crankcase you are stuffed, i cant believe he has stripped the threads on the bolt as its steel in an alloy case---if he means he's rounded the hexagon you need a new proper bolt as its also a pressure relief valve

[Soos]

I believe it is 18x1.5....


I have a die I used to make a new bolt for my custom spin oil adaptor I had made....
I'll re-post when i get to my garage at home and let you know.
If the threads are stripped out, he might be able to have a machine shop helicoil it for him.
Probably cost 30-60$ for them to do it though.

If it's the bolt itself thats stripped, I got one I will sell cheap.


l8r

[donaldb]

No its the case that is stripped not the bolt, so you think its m18 x 1.5?

donald

[Soos]

Sorry, I was wrong there.

I just went into the garage, and checked, it is actually 20X1.5

How handy is your son?
Helicoil is one option the other would be to make an insert for it.
Helicoil fix would be easiest to do.
mabey a longer bolt?

When I was looking at the threads, they go pretty far back, and 1/2" longer would do the trick, and not block anything(too bad).

Perhaps he could get a (750?, 550?) oil filter housing and use the stock cb650 bolt.
I can't remember which is shorter, the 550's or the 750's.

Another option, get a spin on oil filter adaptor.
If he measures how far in the threads are stripped, he could possibly get a bolt with the adaptor that is long enough.
Terry From australia sells kits, and I believe he makes them himself, so a custom length bolt would not be a big problem i think.
You would have to ask him.


I have one i'd be willing to sell of my own make as well.
fuzzy picture, but thats the one.



l8r

[bryanj]

Not wanting to be rude but if he has managed to strip out the threads in the case i don't think he is capeable of doing a helicoil, plus the tap for that size is going to be expensive and remember all the generated swarf is in the main oil feed. personaly i would want to strip out and clean the case after repairing, if possible, the thread

[Soos]

 



The DOHC750 used a shorter oil filter housing that might work.
The only problem I could see arising from using a shorter filter housing is the threads on the stock cb650 filter bolt.
You might end up tightening up the bolt, only to have run out of threads on the bolt itself, and not allowing the shorter oil filter housing to seal properly.
They could be chased further up the bolt by a machinist though.


Good luck!
Your son wouldn't be going to school in utah would he?



l8r

[donaldb]

No Arizona
thanks