3J6 engine

[FJ111200]

I've just bought an import SG engine, number 3J6, and was wondering if there is the same problem with the gearbox as on the 2H9.
Also, one of the guys on the UK forum says it has got high compression pistons and bigger valves. Can anyone give me some information on this engine.
All replies appreciated.

[TERJE ANDERSEN]

Hi ,I am not an expert on xs1100 motors, but the transmission is the same as all other xs1100`s. I have not have problems with the 2nd gear on my SG.

[DGXSER]

Teh 3J6 is from an 80 special or SG as stated. They do ude the same exact gear box and will be just as likely to develop the 2nd and or 1st gear issues. If it were me, I'd take the gears out following the dremel method listed here in the tech tips before I put it in the frame. If you are expereienced it may be simpler to just split the cases and do it that way.

As to the valves, they did change the intake valves, I believe it was, in 1980. Due to the larger valve, they also opened up the chamber in the head. To deal with the increased volume, they put a little taller dome in the pistons.

There are many folks here that have intechanged the heads from any year 78 through 82. The cams from the 78 model were supposed to be the hottest. Pretty much the 78 engine is supposed to put out the most power, but in my opinion, unless you ride professional level I doubt you would notice the difference with the grunt these things have.

[FJ111200]

Thanks for the quick replies.

DGSXER,

i have fixed the transmission on my 78 Standard, using the guide on this forum. So, like you say, i reckon i'll do the job on this engine before putting it back in the frame. Better now than to find out in a few miles time.

Thanks again.

[DGXSER]

Glad to be of help. I might also suggest you reshim the valves prior to putting it in.

Earlier this year I helped put a used engine in another members 11 and found out later, after it was all in and hooked up and running that the oil pump drive gear was laying in the clutch pan, it needed the gears repaired, and had a bent intake valve. All of which would have been found in those two procedures and much easier to fix prior to the install.

Good luck on your project.

[FJ111200]

I might also suggest you reshim the valves prior to putting it in.
.

That's what i was thinking.

Thanks again mate.

[trbig]

Where's the other engine? If you've done the fix on those gears already, pull them out and swap them.


Tod

[FJ111200]

Where's the other engine? If you've done the fix on those gears already, pull them out and swap them.


Tod

That's in my garage. See, what happened was, i had an oil leak from the part of the barrel where the front of the cylinder head bolts to. So i decided to fix it, and when i pulled the head off the part of the barrel broke free. So i needed a new set of barrels or an ally weld fix, no one could help on the UK site, and my mates ally welding gear has gone caput, and so then someone found a complete engine and i bought it.

So if i'm going to pull out the gears on one why do it on two? At least then i'll have two gearboxes with the fix done, and then maybe i can use the other one at some time or someone else can.

[trbig]

You should be able to pick up just a set of cylinders pretty cheap if that's the only thing wrong with the other motor. Or... you might try a big glob of JB Weld?

Those bolts in the front and back really shouldn't be holding much in the way of preventing oil leaks. If you go to fix it, I'd loosen your adjuster screw so it's just spring pressure against the chain, then loosen all the head bolts. Do the fix on the broke piece, then re-torque the head down starting with the center studs like the book says and working your way out. Those last two bolts there on the front and back... be gentle with 'em.

If the JB Weld doesn't hold (I know of one member that did this and was holding last I'd heard) then at least you aren't out much time and money.. Could maybe have been your adjuster being the leaky culprit all along?

Just a suggestion.

Tod

[FJ111200]

You should be able to pick up just a set of cylinders pretty cheap if that's the only thing wrong with the other motor. Or... you might try a big glob of JB Weld?

If the JB Weld doesn't hold (I know of one member that did this and was holding last I'd heard) then at least you aren't out much time and money.. Could maybe have been your adjuster being the leaky culprit all along?

Just a suggestion.

Tod

Hey Tod, i'm too far in now mate. As i said, no one came forward on the UK site except for Mick, who's got some barrels that need a re-liner on one pot.

I tried that adjuster being the culprit countless times, no go there.

I tell you, i've been there bought the t-shirt mate, if i could have gone for the simple solution i would have.

Anyway, all good fun,

thanks for the input,