• Ciao Guest - You’ve landed at the ultimate Guzzi site. NEW FORUM REGISTRATIONS REQUIRE EMAIL ACTIVATION - CHECK YOUR SPAM FOLDER - Use the CONTACT above if you need help. New to the forum? For all new members, we require ONE post in the Introductions section at the bottom, in order to post in most of the other sections. ALWAYS TRY A SEARCH BEFORE STARTING A NEW TOPIC - Most questions you may have, have likely been already answered. DON'T BE A DRIVE-BY POSTER: As a common courtesy, check back in and reply within 24 hours, or your post will be deleted. Note there's decades of heavily experienced Guzzi professionals on this site, all whom happily give endless amounts of their VALUABLE time for free; BE COURTEOUS AND RESPECTFUL!
  • Be sure to see the GTM STORE link also above for our 700+ product inventory, including OEM parts and many of our 100% Made-in-SoCal-USA GTM products and engine kits. In SoCal? Click the SERVICE tab above for the best in service, tires, tuning and installation of our products or custom work, and don't miss our GT MotoCycles® (not) art on the BUILDS tab above. WE'RE HERE ONLINE ONLY - NO PHONE CALLS MADE OR RECEIVED - DO NOT EMAIL AND ASK QUESTIONS OR ASK TO CALL YOU.
  • There is ZERO tolerance on personal attacks and ANY HYPERLINKS to PRODUCT(S) or other competing website(s), including personal pages, social media or other Forums. This ALSO INCLUDES ECU DIAGnostic software, questions and mapping. We work very hard to offer commercially supported products and to keep info relevant here. First offense is a note, second is a warning, third time will get you banned from the site. We don't have the time to chase repeat (and ignorant) offenders. This is NOT a social media platform; It's an ad-free, privately funded website, in small help with user donations. Be sure to see the GTM STORE link above; ALL product purchases help support the site, or you can upgrade your Forum profile or DONATE via the link above.

Name that cylinder head hole!!!

guzziben47

guzziben47

Cruisin' Guzzisti
Joined
Jun 5, 2010
Messages
191
I have oil dripping from my left cylinder head. At first I thought it was coming from the gasket between the head and the cap (about a half dozen fins down from the top), but then I looked closer and noticed there are a couple holes in between the fins in that area.

One is about an eight inch in diameter in the middle of the head; you can see it with a flashlight if you look straight at the head, in between the fins. I tried sticking the end of a shop swab in there, and it goes in pretty far. I'm not a mechanic but I figure it can't go all the way to the combustion chamber.

The other one is bigger, a couple fins down from the little hole, but it is much harder to see. The bigger hole is maybe 3/8" in diameter, going up into the fin (i.e. in a direction perpendicular to the direction of the first hole). You have to get on the ground and look up at the under side of the fins to see it.

Anyway, the question is does anyone know what those two holes are for? Are they vents, maybe? I'm wondering if there is any reason oil might be dripping out of one or both of the holes, if that is where it is coming from....
 
Um, well no holw apart from the plug 'ole goes into the combustion chamber otherwise the bugger wouldn't run eh?

These little plugs.
4350421778_7918f35cf8_o.jpg


4350421774_2f73cfeb3f_o.jpg


Are the drillings for the cooling galleries around the exhaust valves. The slightly larger one in the right hand edge of pic #2 is the drain hole from the plug tunnel which is there to allow water to get out if it gets in through the air vents at the front and back into the plug tube. If oil is dripping out of there there is a problem with the integrity of the o-rings that seal the tube top and bottom

4350421770_14a6dbf1ef_o.jpg


This one I'm pointing out the internal plug on the end of the cooling gallery around the exhaust valve but you can see the bottom o-ring in the head clearly.

4350421764_32b6ee4728_o.jpg


Another potential leak point is the welch plug in the hole that the oil gallery is drilled through.

4350424358_7e0d1a625f_o.jpg


One of my customers who posts here occasionally had to have a head swapped due to a casting defect. It's doccumented on this site somewhere. But that is the only case of that type I've heard of. My guess is it'll be an o-ring failure.

Pete
 
So, just so I understand what you are saying, the problem is likely one of the o-rings for the spark plug tube? If that's it, I know I can see the top o-ring when I take the valve cover off; what do you have to do to get to the bottom o-ring, take the cylinder head off?
 
I just took the bike for a ride, and I think it's the other, larger hole that is leaking. The oil is on the bottom of the nineth fin from the top and the top of the tenth fin (i.e. it's all over the the area where the cylinder head meets the body of the cylinder). There is a gasket there, where the head attaches to the cylinder, so it may be the gasket. But that's also where the larger hole is (if you took the cylinder head off and turned it over, you would see the larger hole I'm referring to).
 
Can you post a pic of which hole you think is leaking? I can't for the life of me think of any 3/8th holes in the 'ed but I'm about to duck off to the W'shop so I'll have a look at the one on the bench. Is it at the frony of the outer edge of the cylinder head or roughly central?

Pete
 
Here a photo of the hole the oil appears to be coming from (attached).
 

Attachments

  • DSC_0082.JPG
    DSC_0082.JPG
    254.3 KB · Views: 445
It looks like the same hole you can see in the bottom right hand corner of the first image you posted....
 
Turned out it was the oil pipe going into the back of the cyclinder head that was leaking. They tightened it up and now it is fine....
 
You must log in or register to reply here.
Back
Top