Woo

....etc.

Just picked up a shiny new barrel & piston for the Guzzi.

I haven't dared look at the invoice yet.

 

About an hours work to get it all running again then? (1)

<cringe> I suppose that's got to be the thick end of £200-£230? I've never
bought any Guzzi nikasil barrels. Mine are all the older steel liner type
thanks God.. Hope the reassembly all goes well.

(1) I once amazed a few colleagues by doing a head gasket job on my old
Spada in the lunch hour and still having time to clear up and have a
sandwich. I *do* like OHV engines.

JB

 

It would have been close to that, but I've got a full service to do,
including fuel filter change. I've also got to do a couple of tests,
like make sure the FI pump is working properly, 'cos at present I
don't really know why it failed.

My current theory is that I reckon it has always run a fraction lean
(a regular 55mpg from a quarter-tonne of skyscraper-tall trail-style
bike is a tad suspicious), combined with the fact that the spark plug
was loose and might have overheated. Add to that the fact that I was
using cheap oil...

You're about right. The bill was nearly £240 but included service
items (air & oil filters) and sundry O-rings, etc.

One thing I have noticed is that the new piston is more-or-less
identical to the original *except* that the CR is a tad lower. Ho hum,
I think I'll just live with it; I doubt I'd really notice the
difference, so long as it doesn't really screw up the mixture. I
suppose I'd better make sure it weighs about the same, though.

 

I haven't any experience of the Guzzi FI system as such just yet, although
I'm going to add the FI system from a Cali EV at a later date to my Spada
Trike. The 'slightly-larger-than-standard' PHM38s are a bit thirsty.

^^^^^^^^^^^
This I reckon, is where your problem lies. Guzzis in general run 20-30°C
hotter than most modern air cooled engines. From experience of doing many
rebuilds on other peoples Guzzis over 20+ years, the common factor in all of
the bore/piston/rocker/cam-follower wear/failure problems I've seen, has
been crap (or even mediocre mineral) oil. I've always used fully synth in
all of my Guzzis and I've always run them pretty hard. Millers fully synth
20/50 (summer) or Halfords own 5/50 fully synth (winter) is the order of the
day. My current engine in the trike has now got over 241000 miles on it
(177000 of which I've done myself in the last 18yrs I've owned it) and my
last solo T3 got to 214000 before needing an oil pump and cam/ followers.
The common factor in all of this has been regular changes of fully synth
oil.

Pretty fair price. Wonder what it would have been for a Harley or Duke?

You think you'd really notice on a Guzzi? :>)

cheers,
JB

 

Using the patented Mavis Beacon "Hunt&Peck" Technique, JB

Well, within a pound or two would be a good thing, no?

--
Wicked Uncle Nigel - Podium Placed Ducati Race Engineer as featured in
Performance Bikes and Fast Bikes

WS* GHPOTHUF#24 APOSTLE#14 DLC#1 COFF#20 BOTAFOT#150 HYPO#0(KoTL) IbW#41
SBS#39 OMF#6 Enfield 500 Curry House Racer "The Basmati Rice Burner",
Honda GL1000K2 (Falling apart) Kawasaki ZN1300 Voyager "Oh, Oh, It's so big"
Suzuki TS250 "The Africa Single" Yamaha Vmax Honda ST1100 wiv trailer

 

The thing is though, it was fully synth and there is no sign of wear
anywhere else apart from the seizure points: the piston, bore & rings
are completely and heart-breakingly pristine otherwise. The other bore
is showing excellent compression. Also, the wear points aren't on the
sides of the skirt WRT the gudgeon pin, they're sort of on the
diagonal, which implies that the piston had gone oval along the line
of the pin.

Could the oil really cause this, bearing in mind that it'd done some
6000 miles on this brand?

Mind you, I'm not going to risk it again.

I've looked it up: it's actually the wrong piston AFAICT. It's a Cali
III/ SP II 9.2:1 piston, whereas the Quota has a 9.5:1 piston which it
shares with the 1000S and SP III. Ho hum. I'll have a word with Corsa
Italiana.

There are several solutions, some more bodgy than others, if they
really can't source the correct piston.

 

Ah. I didn't realise it was fully synth you were using.

Assuming the oil was at the corerct level. What sort of state is your oil
pump in? I've seen pretty horrible wear on some square barrel Guzzi oil
pumps. I reckon they must have had a few dodgy ones creep threough the QC
process. It's worth a quick check.

I reckon fitting that piston will cause 'issues', even on a Guzzi.

I'm surprised they screwed up. I've never had any gyp with them at all. Hope
you get it sorted out.


JB

 

Definitely; I checked it after the event just in case. The engine does
use oil but mostly as various slight weeps. Years of owning shite old
oil-burners means that I do check oil levels regularly. How regularly
depends on the bike and how often it's used.

That I don't know. I can probably check the oil pressure easily
enough.

So am I; never had a problem before.

 

Well, they didn't, it seems. Apparently Guzzi simply merged the part
numbers with the 1000cc California line instead in some way. I guess
that it's now been ten years or so since the last Quota rolled off the
production line and they were poor sellers, so they're just not
supporting them.

 

Hello

1000 Quota use the 88 mm bore piston designed for the 44/37 heads with a
medium dome (4.06 mm), just like:

1000S with "VN" serial engines,
1000 SPIII,
1000 Strada,
1000 GT with 36 dell and 44/37 heads
California III with 36 dell and 44/37 heads

California III with 41/36 heads use a lower dome (1.78 mm) piston, like
the 1000 G5, 1000 Convert, 1000 SP and SP II.

The 47/40 heads engines use the highest dome piston (14.99 mm):
1000 Le Mans IV, 1000 S with VV engines, Calif 3 with Dell 40 and 47/40
valves.

HTH.