crud! leaking cylinder gasket!

ok, this officially sucks. the cylinder gasket on the Seca leaks a little bit of oil when the bike is running. as far as I can tell, there's no vacuum leak... just oil accumulating on the very front of the gasket. I've not had to add any oil yet, which tells me the leak is quite slow, but it's driving me nuts nonetheless. I mean, this is not a Norton! *duck*

so, I guess I'm looking at replacing the gasket(s) this winter. A million questions come to mind, but I'll ask only a few :mrgreen:

-for someone who's never cracked open an inline 4, how daunting is the task?
-what other potential problems should I look for while I'm in there?
-what hardware cannot be re-used, e.g. bolts, nuts, washers?
-the cam chain looks pretty good, still tight. should I replace it anyway, since it has 45K on it?
-does the plant have to come out of the frame?
and finally, what is the best (read: not the most expensive) place to get the required gaskets and hardware?


Mentally, I'm ready for the task... Mechanically, well, that remains to be determined

 

You sure it's not leaking somewhere else and just ending up there? You'd have to pull the head and the jugs for that, dunno if it's really worth it. Did you try re-TORQUEING (NOT overtightening) the cylinder base bolts/nuts? I'm pretty sure you CAN do the work with the mill in the frame, it's just a lot of work. If indeed it is leaking from where you think, personally, I'd live with it (provided it doesn't worsen) until I had a more pressing reason to tear down the top end. Oh, and Nortons don't leak oil, they perspire it. BSAs and Triumphs leak.

 

I've re-torqued the acorn nuts on the top. I also fixed a couple of leaks on the valve cover, which I thought was the culprit. Well, now the valve cover doesn't leak, but there's still a bead of oil on the cylinder gasket after a few miles of highway riding. I've looked for other places it could be coming from, but so far I've not found any other leaks.

I'd live with it but it will drive me nuts because I know it's there. Also, this means I can't take the bike to Hallet to open it up in the twisties... They don't like leaky bikes.

...perspiring? is that what they call it? My father-in-law's 850 Commando "perspired" about a pint every couple of days...

 

Suggest using 10- 30 oil ?? Had an Alfa that would piss out oil on start up "till an Alfa Mech told me that 10/40 was too thick.
You REALLY do not want to open it up for that V Minor leak... but you won't fully realise the wisdom of that untill yer knee deep into it.
G'luck.

 

Permatex sells a spray-on gasket sealer that you could try rather than pull the motor apart.
Not a difficult effort in pulling the 4 cyl. apart, just keep clean and organized.
Replacement items on the motor- Starter clutch rebuild, starter chain tensioner/guide replace, valve stem seals.
Anything I missed?

 

Robert, are you talking about Spray N Seal?

 

Mine has a little oil on the fins too but not enough for me to worry about. You see I'm an ole Harley guy. And my bikes never leaked oil but they sure did mark their territory a lot.

 

I just had a similar problem with my pickup. I have an old 1993 Ford pickup the leaked (literally dripped) oil out of the oil pan. The gasket was deteriorated to the point there it should be replaced. Instead of replacing it, it cleaned off the area where it leaked with brake cleaner and wpied it off good and clean. Then I coated the area with Automotive Goop to seal it. I just got back from a test drive and ....NO LEAKS!!
I assume it would work on your bike as well. It dries clear so it won't be noticable and should do the trick. It's worth a try.

 

No Stereo, but that is the newest product release (http://www.permatex.com/products/Automo ... Repair.htm).
This is what I was referring to, the original stuff(http://www.permatex.com/products/Automo ... Repair.htm).
I've no experience with the new stuff but the old stuff worked just fine on my truck (didn't want to replace a leaking head gasket).

 

I scored a can of Spray N Seal at Autozone, which is weird cause I could not find it on their web site. I applied about 4 coats of the stuff on the gasket. It's kinda neat. It dries to a nice, clear rubbery glaze. I'll find out how well it works once Gustav's remains depart from the area, and report back. It also seems like a perfect sealant for intake boots (I have a small tear on one of the airbox boots, from taking the carbs off about a million times).

If it doesn't hold, my father-in-law's buddy said he'll help me tear down the top end, which he's done a bunch of times on his Commando and Atlas..

got my fingers crossed.... 8O

 

Stereomind:

If you do pull the Head and go after that leak ... there are some other things you should plan on doing while the Head is off the bike.
Straight edge the Mating Surface
Have it plained if there is warp.
Valve Seals
Lap Valves
De-carbon; complete ... Combustion chamber, Exhaust Ports, Exhaust Valve Stems and Faces, Piston Crowns

 

Rick, if it lasts until Winter, I'll probably get after it then. I was also planning on replacing the cam chain. I also found out that my local bike shop has a fairly low-mileage, complete motor which they will part with for $300... The parts guy is supposed to call me with exact mileage and compression numbers.

 

$300? It had better be immaculate enough to eat off of and include the carbs.

 

ok, so I talked the guy down to $275 on the motor (yeah, I'm a hell of a haggler :roll: ). It has 5K on the clock, and has good compression. The alternative is: gasket kit, cam chain, rings, machine work (to true up the heads), valve lapping... And I'd still have a 45K transmission which may or may not be a problem down the road...

I'm pretty tempted to just replace the mill, and keep the other one for parts (or part it out and get my $$ out of it).

what would you guys do?

 

If the 5K mileage motor includes carbs and is for real, it seems like a lot more economical than a bunch of major work on a unit with 45K miles. If it doesn't include the carbs, what I would NOT do is give the guy $275. More like $200 max.

 

I'd haggle some more. Low mileage? How do you know it's mileage? I wouldn't count upon any yard giving you the true mileage as they will not bother to look past the trashed, beat-up bike they just scrapped to note that the 5K odometer seems a mite fishy. Compression test only and take that with a healthy dose of skepticisim. I'd part with $275 only if the carbs and all the little goodies (like an oil cooler) were still on it.

 

stereomind,
Got halfway through the tread before I realized you said Hallet. I'm to your West a little ways, Stillwater. Now if only this darn weather would clear up...

 

Cool! been to Stillwater a couple of times... Maybe we can go for a cruise some time! I got a buddy with a XJ1100 too.

KD5WUB :mrgreen:

Robert -

Funny thing, that same bike shop gave me a set of carbs off a 650 for free, which were not pristine, but I ended up using a lot of the parts off of them. I also fix their computers, so it's not in their best interest to screw me over... I'll talk to the owner and see if they can come down some more. One thing for sure, those motors are very rare in these parts... As in, almost non-existent. Even if I found a cheaper one elsewhere, it would cost a bunch to get it here... Just a thought....

 

Figuring time and tribulations into the whole thing ... I'd grab the known good engine and make the old engine a project engine.

You can put the used engine in ... in a few hours and have the rest of the riding season to enjoy ...
Plus ... have a lot of time working-out the problems with the old engine if you care to even go there.

 

You didn't say you KNOW the guy selling the engine...if XJ mills are that rare in those parts, the $75 difference won't even pay shipping. Previous opinion retracted, I agree with Rick...

 

that's the encouragement I was looking for :-D

I'm gonna go look at it this weekend and see if it's up to snuff.

 

I have just changed my head gasket on my bike also had the same problem you have. I t wont get better it will get worse. You can change your head gasket without removing the motor from the bike. Good luck.