[neatochris]

Well, the tranny is nice...but now I must yank the 390 and do a rebuild...well, have a rebuild done....maybe you guys can help diagnose the problem (but I know a full rebuild is on the horizon in the VERY near future). Going about 30 mph down the road is okay, but when I give it some gas after traveling a bit at 30mph, BIG OL puff of blue smoke....then it trails for a bit....and then kind of trickes out at idle...bummed about it....think I'm going to sell the 69 Charger to help the 390 fund. Doesn't seem to have any water in the oil or vice versa. When I get the rebuild done, will most places replace the pistons? I don't want to lose the 10:1 compression of the S code...does that usually cost extra? I'm guessing about 2K for a rebuild....and will probablly do a little bit of a cam, but not much...this is in the 68 xr7GT.
Thanks for reading
Chris

 

[ZeroTolerance]

Chris, it sounds like your valve stem seals are shot. I'm not saying your motor doesn't need a rebuild, but that's my guess as to where the smoke is coming from when you nail the gas. Do you get a big cloud of smoke when you start it cold? Like first thing in the morning?

Might be worth checking out. Maybe Royce or one of the other guys will come in and back me up, or set you straight.

You'll wind up putting new seals in when you rebuild the motor anyway, part of the cylinder head treatment.

 

[neatochris]

Startup is fine....no noticable blue at all....kind of strange....kind of funny because there is a bad exhaust manifold gasket leak on the side of the motor that puffs blue, so when it really puffs, I get a little blue coming up out of the hood...at least the differential is still tight.
Chris "puffy" D

 

[Ray]

blue on acceleration/uphill/load is rings . Blue on decelleration/downhill is valve seals

 

[gt390xr7]

Hey Chris, The two things you should check before you yank the motor are the trans modulator and the brake booster. These will you off idle smoke because of the high vacuum. There easy to check and may save you a rebuild.Just yank and plug the vacuum lines one at a time, and see if your smoke goes away. But be careful your trans won't shift and your brakes will real hard...

Bruce