Pulling XT350 cylinder to fix oil leak?

[Skinsfan6]

Hey guys. 96 XT350. I have a very slight oil leak under the right rear corner of the cylinder on my XT. It gets damp with oil after a substantial ride 2+ miles. It is probably not anything I need to pull apart and fix, but I figured I would see if anyone has had their cylinder off. If I can pull the cylinder and slap a new gasket on without having to hone it or do much nonsense I may do it to make my becoming-vintage XT leak free.

So can anyone give me a basic list of steps to replace the base cylinder gasket? Are there any tricks I should know about other than simple disassembly and reassembly? I have a pdf Yamaha service manual that is pretty worthless, but I think I will pick up a Clymer manual I spotted at the stealership a few weeks ago.

[pd350]

You can download a free manual here :

http://www.carlsalter.com/download.asp?p=1359

I have a manual exactly like this ( and the one from carlsalter.com ):

http://www.ebay.com/itm/ORIGINAL-1984-YAMAHA-XT350-N-NC-SERVICE-MANUAL-/360345435019?pt=Motors_Manuals_Literature&vxp=mtr&hash=item53e642fb8b

It is very thorough . The seller seems a bit confused , but if the manual they are selling is what is pictured , you should be good ( N is the 1985 year designation ). Remember that the XT350 is the same bike ( other than color scheme ) from 1985 through 2000 .

[jsnmid]

I've had the cylinder off a few times. If you are comfortable with a wrench, it's pretty easy. You can do it with the engine in the bike if you want. It will also be a good time to check/adjust your valve since you will have the head off anyway. Just remember to measure them before you remove the cams. I always forget for some reason. They will likely be ok though.

I usually put new rings in and run a hone through the cylinder if I have the chance. You dont have to, but it's a good idea on an older engine.

The Clymer will walk you through it. I can't think of any tricks other than tying up the timing chain so you don't drop it into the case.

[Skinsfan6]

Excellent. I'll pick up the Clymer Saturday and replace the gasket next time I'm home. ? My XT only has 3,800 miles on it and I'm running short on time and money before I go on a weekend trip with my dad, so I'm hoping to get away without rings and a hone this time.

[pd350]

I'm running short on time and money

We use to cut our own base gaskets out of cereal boxes . Now , I use a rubberized gasket material I get from NAPA . Last I bought : 7 bucks gave me enough 'paper' to gasket a complete motor and still have a bunch left . It's pretty tough stuff . I like it a lot better than the OEM gasket material .

[jsnmid]

If you're short on time, leave it alone for now. I'd only do it when i can take my time. Mine leaked at the base for a year before i got around to fixing it. Just keep an eye on the oil level.

If you decide to make a gasket, make sure you use the same thickness as stock or you will be changing the compression. Too thin could be very bad. I'd go with a full top end gasket kit. It will have the base o-ring and head gasket which you can't make anyway.

[pd350]

head gasket which you can't make anyway.

Well, Yes you can , but ... That's a matter for 'tomorrow . ?

[jsnmid]

Well, Yes you can , but ... That's a matter for 'tomorrow . ?

True... but the o-ring is really hard to make:p

Regardless, I wouldn't advise opening up a low milage engine that runs fine just before a trip to fix a little seepage. The o-ring will stop it from becoming a major leak. Do it when there is more time.

With only 3800mi, i wouldn't bother with rings, or valves either. It's barely broken in.

If you really want to do something, pull the cams and retorque the head(loosten the bolts a hair first).

[pd350]

Regardless, I wouldn't advise opening up a low milage engine that runs fine just before a trip to fix a little seepage.

Agreed .

[Skinsfan6]

I think I will wait until after the trip and maybe do it the week or two I am home afterwards. I will order a gasket kit because I don't trust myself cutting new gaskets. The seepage is annoying but I'm almost certain the oil loss is negligible. Last oil change I put a little lucas oil stabilizer in the oil ~100ml maybe. I do a lot of highway riding at around 4500-5000rpm and I had been noticing a little oil loss. The oil loss has slowed down, and visually, the seepage appears about the same. So I'll let it ride til after my trip.