1986 tecate / kx250 blown head gaskets - a common problem??????????????

[nd4speed]

Well I Bought a 1986 KX250 and the head gasket was blown. So I rebuilt the top end and a couple years later it is in my Tecate and it seeps a tiny bit near the center of the head but basically in the same place as before.

In april 2007 bought a 1986 KX250 for $250 with a fresh top end rebuild by Magic Racing. Head gasket leaks in center on pipe side. It sprays on my leg some.

My original tecate motor never had a top end leak. Lucky I guess

Maybe it's because the cylinders are sleeved?

Is this a chronic problem????? Head Warping???

Should I be sanding the head flat or somethin?

[fabiodriven]

My 85 always weeps a little from the head no matter what. It's never sprayed though.

[playasridebmx]

theres a couple tecate guys that say never use anything other than a kawasaki replacement head gasket i would assume that the others arent quite as good and cause leakage issues

[fabiodriven]

I use nothing but OEM when it comes to head gaskets.

[nd4speed]

I usually always use Vesrah.

But I just wondered if other tecate owners notice this and whether their cylinder is sleeved. Sleeve looked flush on the one I got to see so far,

I'm not worried about the slight weep on the one, but the other doesnt spray, I just feel drops of coolant hitting my leg when at riding speed.

[hang&rattle]

I had a weep on my 85' motor, I used a run-of-the-mill gasket. It had to be replaced. Same on my replacement motor (don't know what year). Neither one was sleeved. But I think it was what I did wrong nd4speed. I looked up some races and stories from Kawasaki (Jimmy White etc..) and I couldn't find any head leakage problems (thought I read a story on them). But did find some with Honda (R's are good trikes though) and even Doug had some leaks on his. And those drops on your legs may have you stop for frequent potty breaks while on rides, a big hassle, lol.

[Xpress]

Did you check the head for straightness? Also did you re-torque after about 10 hours?

[dcreel]

My 84 has never had any issues whatsoever.. It has a KX cylinder with a KXT cylinder head. The 2 85's I have owned on the other hand.. 1 had a weep the other had a huge leak that I fixed and it moved to forcing it out the overflow.. My 84 I have owned since 1987.. It makes a difference when you know the work that's been done to it.. I've seen people pry a cylinder head off with a screwdriver before..

[nd4speed]

I did the work on the one that weeps slightly. The nuts are torqued tight on that one. But the nuts on the other that leaks more I was still able to tighten on that side.

It's just that I've seen it 3 times now and wondered if it was common. Like the motor mounts get loose and the head stay breaks the seal. Something like that. Or warping head, or whatever...

The one Magic Racing did looks to have cylinder head studs that aren't long enough (or head gasket too thick) because the nuts arent even threaded on all the way. Thought that was interesting from a so called racing dealer.

Oh well I'm just gonna do the one head gasket with a Vesrah cause that's what I have already.

I've seen a beat down 2-stroke motor just crying for mercy from like all it's gaskets and it still started first kick and went fast.

[Tecate250]

Well Need4speed. My old tecate motor use to eat head gaskets almost every time I rode it. Tried kawasaki Cometic gaskets with same results. Bought a tore down 1983 kx 250 all stock. And put the cylinder back together with a used head gasket and still has not leaked a drop. I was thinking of putting 2 gaskets on it due to the 210 psi.

[sblt500r]

my 86 has a sleeve, had to have the cylinder decked 30 thousandths, as the sleeve wasn't flat. used a oem gasket and it hasn't leaked yet. also put a sleeve in sportvettes 86 with a sprock head, no leaks.

[nstyle73]

My Sprock O-Ringed head with sleeve hasn't leaked at all, torqued to 25 in lbs initially and retorqued at 5 hours. The other two 250 motors I have, one has a cometic gasket without sleeve and hasn't leaked, and the other is a stock bore, no sleeve, that I ended up re-using the head gasket that was on it when I put rings in because I was riding the next day and misplaced the new one. Sounded like a bad idea but, hasn't leaked, so I left it. Sounds like I've been lucky though, All are 86's though with the three extra bolts at the front around the powervalves.

[ezmoney1979]

I will add to this, I use Cometic gaskets and have had them make custom gaskets for big bore applications and I have had no leaks. But I take my time and re-torque after a couple heat cycles.

[nd4speed]

I still havent taken it apart to even look at it. I think I have a new head gasket. Winter project I guess. This weekend might be nice.