Topic: Is this leaky pucks?

[Dunk]

My daily rider CB750 is getting oil on the head. Is this pucks? I had the engine out a year ago and did not disturb cam, towers, or head bolts. I tightened loose cam sprocket bolts that were causing a rattle, new valve cover gasket, and back in. It did not leak all last summer and fall that I noticed. This must be recent from my rides over the winter and into spring as it warmed up. This engine was entirely leak free last summer after reinstalling and for years before then.

If this is likely pucks, is there a preferred source for new pucks? I recall years back there were many that were too thin and leaked immediately or shortly after install. Anything else I should do while it's out if I'm going to be thorough and want to ensure no leaks?

[Henning]

Most likely one of the pucks leaking. The original Honda ones are the ones to get, install with a wipe of sealant for extra insurance. How is the condition of the engine otherwise; mine blew a puck seal due to too much crankcase pressure?

[Dunk]

I cleaned the engine up with engine brite and washed the bike, on to some polishing and such. I may be able to get a better idea where it's leaking after another ride or two now that it's clean.

Engine seems to be in good condition otherwise. It starts easy and runs well. I got it up from a forum member in 2015. Aside from an inordinate number of fasteners being loose (including those cam sprocket bolts) it has been fine. I did check torque on head bolts when I had it out last year, none that were accessible moved at all. I believe he at least had the top end apart though I don't recall what he did, maybe just rings. It has a hex screw kit to replace the JIS screws for all covers. I see one spot on the valve cover is weeping, I'll snug up to the cover screws.

I have a gasket kit and some Honda pucks I got a while back to reseal my K1. I buttoned that engine's top end in 2003 and don't recall what pucks I used, but I suspect they were aftermarket.

[caluser2000]

I'd check the head bolts first.

On my CB550F I tweaked the head bolts down another ftlbs and it sorted out a similar leak. Wouldn't go higher than that over torque though.If its really minimal a few coats of l clear super glue. May hold it back until the next rebuld, I did this on my XF650s lecking camshaft plunger housing gasket that was leaking quite bad at over 2,000rpm 12 months ago and it has held out fine.

Gash I know but it's working.

[Dunk]

Looking through old threads and found this. It was leaking pucks. Pulled the engine last winter, pulled cam towers and replaced pucks using Threebond, valve cover gasket installed with Gasgacinch. Hasn't leaked a drop since.

[denward17]

I need to replace the pucks on mine, do you use Honda pucks?

[Dunk]

I'm about 90% certain they were Honda pucks. I recall a thread where Hondaman commented there was some bad batches of pucks, or mislabeled as a later bike take the same diameter but thinner. In any event, search for it or measure the depth of the recess the pucks sit in any ensure the new pucks are at least a few thousandths thicker than the recess in the head. Probably want .030" or more compression on them or more, certainly not much less. Measure them, even if from Honda.

[HondaMan]

I need to replace the pucks on mine, do you use Honda pucks?

If you get them from PartsNmore.com you will get the correct ones.

[newday777]

I need to replace the pucks on mine, do you use Honda pucks?

If you get them from PartsNmore.com you will get the correct ones.

How about South Sound Honda?

[bryanj]

They are not at head gasket joint

[newday777]

They are not at head gasket joint

My bad. Corrected..

[rotortiller]

My take on it with a good running machine is if all you have to do is clean minor residue up every couple of months with varsol, leave sleeping dogs lay. Park next to a vintage British bike or Harley Ferguson and you will quickly feel better. Often enough when you start repairing a minor leak or oil weap things snowball into more expensive branches of maintenance. Oh Euck, I snapped a stud. 5hit I scraped up my frame removing the engine. Darn maybe I should do a top end while the engine is out and oh, I wonder what the primary chain is like since I have access. And the story continues lol.

[MauiK3]

And that's where the fun is!!

[seanbarney41]

I agree with rotortiller....the fun is riding them!