Cad 390 Question

Gotta question for the folks who know. My cad has been through hell and back many times. I beat the heck out of it. It's a 60 sedan for those who don't know me. Original 390 was rebuilt about 2 years ago. Problem at the time appeared to be a blown head gasket. But I figured, heck it's old it should be rebuilt properly so I can run unleaded blah blah blah. Well, long story short, the white smoke that I thought was coming from a blown head gasket was coming from two cylinders that had destroyed the pistons and the rods had come through the water jacket. Prior to rebuild I had some water loss, and lots of smoke coming from the breather cap and the down draft tube down by the transmision. Well, since the rebuild I've been told it's putting out 500 ft lbs and 400hp at the crank. IT's running 87 pump gas w/ no nocks. Doing frickin sweet. Burnouts, no problem. I can spin em both without a posi. I mean tons of power, no problem.

Well, about a month ago, exhaust starts to leak again by the manifold. No biggie. Sounds cool anyway.

Ok.. just finished towing a u-haul from Chicago IL, to Wilmington, NC. In Indy, just past Indianapolis the exhaust starts leaking real serious like on both sides by the manifolds. No problem in my mind. Still sounds cool, and I'm drivin with windows down. No problem.

About in Raleigh, 2 hours from Wilmington I start to overheat. Now mind you, I've already done 18 hours at 65-75mph through the mountains, no problems. SO.. I add a lil radiator fluid. Check the oil, it's down half a quart. For 1000miles that aint bad. SO.. I add oil. and continue my journey.

I'm chuggin along doin bout 80-85, just tearing it up, making great time. Bout 5 miles from my appartment I start to see white smoke from behind. SO.. I pulled over, it's overheating again. I realize I need to add more Radiator fluid, check the oil, it's fine. BUT...Car is running rough as ****. I get in, continue to drive and it continues to run rough, accellerate like ****, and smoke like a chimney.

I figure once again. gotta be a headgasket, why else would I be kickin out white smoke. It aint blue so it can't be oil.

Got the car to a local mechanic. Good guy I hear, all the local's in a big car club use him for major work on there rides, which all pretty much rock. Some are drag strip power houses. Anywho. He tears into it. Head gaskets are good. Checks the radiator fluid with some fancy schmancy tester. No oil. Checks the oil, no radiator fluid.

However.... the breather tube on top, and the down draft tube are kickin out some blue smoke, and lots of white smoke.

This guy is stumped.

I'm totally at a loss

Any suggestions???

I really want my powerhouse back.

Ideas I'm thinking of incude... ignition problems? Maybe bad points?

Perhaps it's the timing?

Maybe the exhaust isn't creating enough back pressure and I'm getting ring blow by?

I'm open to any suggestions or ideas.

 

On the Exhaust leak....What intake are you using? If it's the factory intake there is a tube that goes thru the intake for the choke that is always rotted out. It always makes the engine sound like an exhaust leak on both sides. Does your car have A/C? Has the radiator been rebuilt?

 

original intake,and tube has already been replaced. I can actually see the holes in this job. Yes it has AC, and yes radiator has been rebuilt/re lined. Dat help any?

 

Ok, here's what's up so far. Carb has been checked, tuned, works great on another car. So that's not the problem. Fuel pump is new, lines are good, so fuel is ok. Distributor timing is set properly, wires are good, plugs are good, so Spark is not the problem, although replacing a fouled plug did help. Compression test revealed all cylinders over 130 on first crank, over 150 on second. So, me thinks the rings are ok. So.. problem is, why am I still getting HORRIBLE blow by smoke from the breather tube and the downdraft tube, and a pretty bad miss when I get into the throttle. WTF is wrong with my baby?

 

bttt...gotta be someone here who can help...?

Maybe rephrase the post ***le...? Maybe "Motor problems: Cad 390."

 

Got bad news. mechanic did leakdown test. found #3 cylinder real bad. Could be rings, but prolly piston. which means prolly damaged cylinder, which means prolly more machine work.... and on and on. This **** ****s. Can't a guy catch a break. I just payed like 7 g's to get this **** right not even 3 years ago. Called the shop who did it, they're happy to help, but warranty expired after 1 year, so there happy to take more of my $$$. Too bad I'm in wilmington, and they are in Chicago, or I'd make em fix it for free. But it'll cost me more to tow it there than it's worth. Anybody in NC, SC, VA have a good engine I can throw in there, and the skills to do it, or teach me now to do it? I'm desperate here, and not full of $$$ either. I'd do it my dang self, if I had the skills, and a place do do it. My apartment won't even let me change my oil.