17mm Oil Filter Bolts

[kp]

Eli, the 17mm oil filter bolts are found on later Honda models. Not sure what you guys have there but our Honda CX500, CX550 oil filter bolts are the same as the SOHC CB750 12/14mm bolts. Since we're sharing our secret squirrell info through these discussions, here's a neat trick straight from Bellaricky Dickie. Take a 17mm oil filter bolt to a machine shop, one which has an indexing cutter. Have them take the 17mm filter head down to a 14mm filter head. Smooth out the machine marks, re zinc plate and it's all over rover. Touchdown KP 

[elisent]

Thanks KP, I'm not real familiar with much after 71. Nice tip. Eli

[markb]

So am I correct in saying the the hex was 14mm on sandcasts up to 4148, 12mm after 4148 and 17mm on later models?

[Steve Swan]

i believe 17mm was an after market accessory part.

[kmb69]

So am I correct in saying the the hex was 14mm on sandcasts up to 4148, 12mm after 4148 and 17mm on later models?

Mark, I have to do some research to be sure but I think the 14mm bolts were used into the K1's. I think the timeline stuff on our forum may be wrong regarding this bolt and other oil filter stuff. For example, hondachopper.com says the finned oil filter cover was introduced on 9554. Our forum says 4149. I am pretty sure I remember smooth filter covers on a few very early K0's. I assembled quite a number of SC's, K0's, K1's and K2's out of the crate at Pasadena Honda back in the day before I got a real job. Keith

[markb]

I guess my real question is what is correct for VIN 97?  I have a 12mm that may be good enough to replate and I have 17mm that I could use KP's trick to make into a 12mm or 14mm.  I was under the impression that the hex was reduced on later sandcasts to help prevent cracking of the oil filter housing because the smaller wrench would apply less torque.  Anyone else heard this?

[Wayne]

Mark
That's my understanding as well. As per the distinctions list:

28. round, fin-less, non-webbed oil filter cover, E1-E4148
29. 14 mm hex head, oil filter bolt to E4148, 12mm beginning 4149

[vnz00]

Oops slight typo and modification - 5528 and not 6628.  1853 has a 12mm bolt after recall and replace of fin less oil filter cover.

Hi Guys, thought id chime in on the 14mm bolt situation.

5528 had one, but used a finned, un reinforced oil filter cover. I assume it was original to the bike as it also had 28 caps on it. I.e. Did not see the factory recall.

I have pics too of 5548 which was on eBay a while back. It too had the 14mm bolt.

Maybe a case they changed the oil filter cover at that vin, but continued using the bolts in production. 14mm bolts and finless covers then were replaced as a pair at recall which 1853 seems to have followed. 1853 has also got the unreinforced finned cover but with a 12mm bolt.

Regards,
Steven

[markb]

Thanks for the input.  Sounds like 14mm is correct for #97.  I'll machine my 17mm down to 14mm.  If for any reason I I find that is incorrect I could always machine to 12mm. 

[Steve Swan]

any thoughts on the 17mm being a honda oem part vs aftermarket part ?  the reason i said aftermarket, i've seen these 17mm new in aftermarket blister wrap packaging.

[markb]

Good point.  I'll compare them to make sure there are no other differences.

[kp]

They are probably aftermarket. I thought the ones I had modified were OEM and off the CX500. Nevertheless they are almost identical once machined to 14mm. There are some minor variations in hole sizes which aren't seen once fitted but you would need to have them side by side to see the slight differences.