BEWARE - Clean your crankcase breather

[cycles4fun]

Here is a long winded dissertation to a big problem and a very important tip to remember. PLEASE READ!!!! I recently swapped my lemans MK4 engine with a beautiful low mileage motor from a 2003 V-1100 lemans. It came out perfect and ran wonderful. My old rebuilt motor suffered an oil pressure loss while in route to the 2008 Malibu rally that I never really found the root cause for. I checked all the obvious stuff and it all looked fine. The oil light started coming on at idle and got increasing worse until it basically destroyed itself. That motor lasted around 1200 miles! Instead of going through the motor again I decided to swap in a late model low mileage lemans motor sold to me from a Guzzi dealer friend. I guess I figured the oil pressure loss issue was related to the rebuild and figured my problems would be behind me with the new late model motor. I used the factory ECU for the ignition system and temporarily fitted the 40mm delortos while I source the remaining EFI parts I still need for the conversion to EFI. Ran the motor about 500 miles changed the oil (Mobil 1 V-twin SG rated) and ran it an additional 6-700 miles without incident. Packed down the bike last Thursday and headed out to the national rally in Oregon with a couple companions. Life is good.......so I thought. About 175 miles into the trip we stopped for a break and I noticed my oil pressure lamp was flickering at idle, and was off with a little more revs. Oh no not again, can't be! My head was spinning, could be a possible faulty sender, loose filter, stuck relief valve, or bigger problems like before. A quick check on the stick and it was full. I let it cool down a bit and the lamp remained off on the restart. Humm, what should I do now? I ran it an easy 10 miles and pulled over to check it again and now the lamp was on steady at idle. Crap! My ride was over. Trailer it back home, pulled the pan and found the filter was fine, pressure relief valve was closed and nothing obvious was noted. I then interrogated the sump and noted small chunks of gritty debris. I could not think of any source of it other than the cam chain block but this would not be gritty! This crap did not come from this motor. About then the light went on! Oh crap the breather, I never thought to check or clean it. I disconnected the breather return hoses from the heads and aimed the open hoses into a clear bottle. I then blew compressed air into the large breather inlet and the crap started flying out. Oh no!!!!!!!!I was feeling sick at that point. The grit was fine sand like material and I believe it was trapped glass blasting material that for some reason recently decided to let go. I powder coated the frame a decade or so ago and do not remember ever cleaning out the frame breather!!!!!Perhaps the synthetic oil I started recently using loosened it up. In any event all the aluminum bearing surfaces are now nicely sanded rendering them useless! BIG BIG oversight on my behalf. So the moral to this story, clean the breather! Yours is likely clean as a whistle but you won’t know until you check. If you have powder coated your frame DO NOT start your motor without checking it first. You have been warned!

[jrt]

Thanks for the cautionary tale. I'm sorry to hear about your bearing surfaces and hope you can replace them for a reasonable cost.

You might want to check the sludge trap in your crankshaft before you reassemble.

[cycles4fun]

Thanks for the cautionary tale. I'm sorry to hear about your bearing surfaces and hope you can replace them for a reasonable cost.

You might want to check the sludge trap in your crankshaft before you reassemble.

[cycles4fun]

Thanks, yes I do plan to pull the plug and clean it out. I have to re-machine the front and rear journals but the rod journal is fine. Its funny that the blasting material only damaged the aluminum surfaces and then the roughed up aluminum proceded to damage the metal material spinning within it. The rod bearings look absolutly fine. The real bummer is the oil pump surface on the block and the cam bearings. I can re-machine the oil pump surface .005-.010" cleaning it up and then shim out the sprocket back out for proper chain alignment but not sure what to do with the cam bearings. I may have a line on a new block from a dealer friend. It really sucks as I was so maticulous with this motor going over every detail and never thought to check the frame! Another lession learned I guess.

[Greg Bender]

Hi cycles4fun,

 

I'm very sorry to hear of your troubles.

 

I loathe the in-frame breathers because they are nearly impossible to thoroughly and adequately clean. My Quota's steel frame (with in-frame breather) worked perfectly. But, I started to notice small flecks in the sump during oil changes and the same small flecks in the valve covers. The flecks were attracted to a magnet. The source? Rust from the inside of the in-frame breather.

 

I tried creating a number of breathers to replace the original, but none of which worked as efficiently as the original in-frame breather. I finally gave up trying to replace the original. I now run clear filters in the breather lines to prevent any of the rust from getting back into the sump. A perfect solution? No. But at least I'm keeping it out of my engine.

 

Regards,

 

Gregory Bender

[belfastguzzi]

Rust in the system, gosh, yes. Condensation is a particular problem here where the atmosphere is (damp and cold) and a lot of journeys are short. I've posted pictures before of the permanent pool of water that sits in the V.11 frame just at/below the outlet.

Here's one:

 

Every time I take pipes or valve covers off the Guzzis they are thick with emulsion and dripping water. I'm bothered about the heavy mayonnaise emulsion in the Griso 8V heads. Unfortunately there is really nothing that can be done about this, given the reality of short journeys (and damp climate?).

[belfastguzzi]

Mmmm. This water and gunk is what was in the spine breather. Are these the sort of flecks that you're seeing in the sump, Greg?

[luhbo]

Wouldn't care too much about this, besides that it may weaken the frame after some decades. Should those particles hurt your engine they should first have passed the oil sieve and following that the oil filter. To me this seems rather unlikely.

 

 

Hubert

[gstallons]

Wouldn't care too much about this, besides that it may weaken the frame after some decades. Should those particles hurt your engine they should first have passed the oil sieve and following that the oil filter. To me this seems rather unlikely.

 

 

Hubert

 

You should look at your oil screen/ pick-up/oil sieve. This component is meant to keep out particles larger than the screen. ANY thing smaller goes in to the oil pump and throught the filter then to the lubrication system. The oil pump is the first to get any contamination and the influence from it. An oil pump with aluminum components is going to have accelerated wear. This will cause an oil pressure drop then things go to Hell quick.

I would suggest a (stainless if there is) steel wool pad in the breather hose. This will keep this debris oult of the crankcase.

[Kiwi_Roy]

Every time I take pipes or valve covers off the Guzzis they are thick with emulsion and dripping water. I'm bothered about the heavy mayonnaise emulsion in the Griso 8V heads. Unfortunately there is really nothing that can be done about this, given the reality of short journeys (and damp climate?).

It's quite damp here in British Columbia but I see no sign of emulsion in my engine. perhaps you could try a desicant canister between the spine and where it joins the intake just below the filter. Isn't that where moisture would enter?

BTW, I'm new to Guzzi so don't take me too seriously, I may be out too lunch

[Greg Bender]

Mmmm. This water and gunk is what was in the spine breather. Are these the sort of flecks that you're seeing in the sump, Greg?

 

Yes, the darker particles is what I was seeing in my Quota's sump/valve covers. I did not see the lighter colored material.

 

Regards,

 

Gregory Bender

[Greg Bender]

Wouldn't care too much about this, besides that it may weaken the frame after some decades. Should those particles hurt your engine they should first have passed the oil sieve and following that the oil filter. To me this seems rather unlikely.

 

 

Hubert

 

Hi Hubert,

 

I agree that the likelihood of these particles getting to the mains or big end bearings is pretty unlikely. At the same time, I'm a bit of a Nervous Nelly about particles getting splashed around onto surfaces where they shouldn't be (cam lobes, cylinder walls, etc). Plus, I don't like them up on top of my cylinder head where the oil return lines from the breather deposit the flecks with enough "force" that some of them stick to the valve cover. Surely some of those flecks get where they shouldn't be.

 

The bottom line, IMHO, is that those particles belong no place inside an engine.

 

Regards,

 

Gregory Bender