MonteCarloTerp Posted May 22, 2006 Share Posted May 22, 2006 Ok, let me start by saying I have a 70 with recently rebuilt 400sb, matched with the original/stock coverter and TH350 trans (B&M shift kit installed) Driving around 1 day about 2 months ago, I stopped for gas. When I tried to start up the car again, the starter (new) made a strange whirring/grinding sound. I chalked this up to a hot starter problem and had to wait 10-15min to get going again. But this is when the real problems started. Pulling away from the station, there was a loud bang (like something shifting around) and the car started vibrating real bad (running rough). I limped the 2 miles home. I havent had time to work on this until now. Ive started with the simple things: change the motor oil, check the timing, reset carb air/fuel. No problems there. So heres the summary: 1. Car starts good and idles in park intially as normal (no vibration/rough running) 2. Shift into drive/rev the car starts running rough (shaking pretty bad). It seems to get worse with time. 3. There is a small leak from I *think* the front tranny seal - hard to track it 4. Car is very difficult to shift back into park (this is a new problem) In fact, I seem to be getting more and more trouble shifting the car back into park. The latest problem is that even through the shifter was clearly in park, the car didnt seem to recognize this and refused to start. I jiggled the shifter and this time the starter made the same whirring/grinding sound. I then ran the shifter up and down through the gears, but when I did this a huge plume of white smoke came out of the engine bay (car not running, but the engine/headers were still very hot). I decided to stop for the night at this point. The starter problem may or may not be related to the rough running (the real problem). But it is a brand new starter (I replaced the old one for the identical problem). So I need some theories of what is going on here and hopefully some kind of plan. Thanks for reading this long post, Jon I just want to add that I checked the bellhousing and torque converter bolts and they seem ok. Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted May 22, 2006 Share Posted May 22, 2006 Have you checked the condition of flex plate, I've seen them crack in the area where they bolt up to the crank, the wierd relation to the starter and fld leak?.. kind of lead me in the direction of the bellhousing, starting noise kind of weird though, when you say the starter is making noise.. do you mean it's laboring or bendix drive engagement misaligned? Usually alot of the crappy stater rebuild castings have alot to be desired and in some cases you may require some shims for proper engagement, unless the flex plate comes appart or it begins to crack, the difficulty of it not going into park.. that maybe a linkage problem did that just start-up? who rebuild the motor?, did you have the tranny rebuild, I suspect something broken or loose in the area where the engine and tranny meet? Keep us posted with results? Rod Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted May 22, 2006 Share Posted May 22, 2006 I agree with Rod, unbolt the torque conv, push it back and try to look at the flexplate Sam Quote Link to comment Share on other sites More sharing options...
Mikstudie Posted May 22, 2006 Share Posted May 22, 2006 You really need to look hard becuse as Rod said they crack beetween the bolt holes and are very fine hairline cracks. Iv'e pulled flex plates that were cracked around all 5 holes,it's not that uncommon!Address one problem at a time,it's usally the best way!I hate to say it but i think you have more than one problem. Mike Quote Link to comment Share on other sites More sharing options...
MonteCarloTerp Posted May 22, 2006 Author Share Posted May 22, 2006 Alright, I will look at the flex plate more closely next time I can. I will keep you updated. Any chance that all these problems are related to a bad torque converter? Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted May 22, 2006 Share Posted May 22, 2006 rule out the flywheel first, also check "ALL" the teeth on it, if you start looking at more than one thing, you could come up with more than one answer Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted May 22, 2006 Share Posted May 22, 2006 I just read your post again, you have a 400 small block?, check the flywheel, 400's are externally balanced, did you throw the weight(welded to it) off the flywheel? that would sure explain the vibration Sam Quote Link to comment Share on other sites More sharing options...
MonteCarloTerp Posted May 29, 2006 Author Share Posted May 29, 2006 Ok, I did some digging today. The car seems ok until RPMS drop to normal idle speed (after the car warms up). Then it gets rough and I get some RPM variation (small up and down fluctuations). 1. After unbolting the torque converter, I checked the flexplate very closely, nothing out of the ordinary. All teeth are good. Also the balance weight is still there. 2. I dropped the tranny pan, no metal pieces, but I did find one problem: ^^^ The circled bolt hole above is stripped. I have the B&M kit installed, so its holding the middle support plate, the oil transfer plate, and then the stock spacer plate together (in that order). Its suppose to be torqued at 100in-lbs. I must have done this when I installed the kit a few months ago. But I dont see how this is related to any sudden vibration problems. Also there is no binding when I move the shifter anymore (????). Maybe this isnt a tranny problem and I'm looking in the wrong areas? But that doesnt explain the trouble shifting and the white smoke I had... All I know is there was a loud bang and now the car runs rough at idle speeds. The starter problem I don't care about unless its related to the roughness/vibration. So confused, Jon Quote Link to comment Share on other sites More sharing options...
Rob Peters Posted May 29, 2006 Share Posted May 29, 2006 I am wondering now if you didn't jump a tooth on the timing chain and that was the noise you heard. If the timing if off by one tooth it will cause idiling problems and starting problems. Quote Link to comment Share on other sites More sharing options...
MonteCarloTerp Posted May 30, 2006 Author Share Posted May 30, 2006 That would suck to pull off all that stuff to check...you think I could tell with a stethoscope or something? Quote Link to comment Share on other sites More sharing options...
Mo's70MCs Posted May 30, 2006 Share Posted May 30, 2006 trouble shifting and white smoke? I would relate that to maybe and usually a xmsn modulator, often when they blow they start sucking fld right up the hose into the intake manifold, I'm sure the timming issue could be checked without tearing into it! If it jumped a tooth in timing I'm sure you would have known about it. You'll see fld dripping out of the modulator if you unplug the hose. Rod Quote Link to comment Share on other sites More sharing options...
MonteCarloTerp Posted June 19, 2006 Author Share Posted June 19, 2006 Changed tranny filter, fixed loose oil plate bolt in tranny, replaced tranny modulator. Found the wire from the starter to HEI dist was completely fried. Not sure how this happened, but it was burnt to a crisp. Replaced that wire. Car still idles rough with RPM fluctuations. Maybe I'm looking in the wrong place, I think I will repost this in the engine forum. Quote Link to comment Share on other sites More sharing options...
Guest Posted June 20, 2006 Share Posted June 20, 2006 Wonder if you did some damage to the HEI when that wire fried. Just a thought of what might cause the rough running. You didn't mention what kind of BANG you heard. Was it a mechanical clunk sound or was it a backfire? Quote Link to comment Share on other sites More sharing options...
Reaper Posted June 20, 2006 Share Posted June 20, 2006 Rough idle at idle could be a timing ussue deffinetly but that wouldnt explain the shifting or the white smoke... You said there was some leaking... did you check more into that? Tom Quote Link to comment Share on other sites More sharing options...
Reaper Posted June 20, 2006 Share Posted June 20, 2006 Also does it have a problem starting other than the starter skipping? Quote Link to comment Share on other sites More sharing options...
MonteCarloTerp Posted June 21, 2006 Author Share Posted June 21, 2006 Ok, couple things to respond to: 1. The "bang" sounded like something shifting/moving and I felt something through the floorboards (my foot was on the gas). Not a backfire. 2. I don't think the HEI is damaged because my timing is still were it was before the problem. (Atleast without vacuum using a timing light) 3. I still never really found the source of the leak, but I'm 99% sure its from the front tranny seal/torque converter (i just cant see for sure) even though I did replace that seal when I put the new engine in. Also - that white smoke could have been that wire melting. It was completely fried...not sure if wire sheathing can produce that much smoke, but maybe. Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted June 22, 2006 Share Posted June 22, 2006 check your drivers side engine mount, if it broke, that could explain the bang and the shifter problems, if it did and the engine moved that much, it could of pinched that wire causing it to fry Quote Link to comment Share on other sites More sharing options...
Heckeng Posted June 22, 2006 Share Posted June 22, 2006 Bones, excellent thought!!! You should be on CSI! Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted June 22, 2006 Share Posted June 22, 2006 well, we've thought about everything, why not take a look, put a wood block under the oil pan and jack it up, what do you have to loose? Sam Quote Link to comment Share on other sites More sharing options...
Guest Posted June 28, 2006 Share Posted June 28, 2006 SCREW CSI....where's columbo??? " just one more question sir, just one more question " lol Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted June 28, 2006 Share Posted June 28, 2006 Terp, wear are ya what to hear what you find we got to get to the bottom of this Quote Link to comment Share on other sites More sharing options...
MonteCarloTerp Posted June 29, 2006 Author Share Posted June 29, 2006 Sorry guys! Been keeping up with this thread, but haven't been around the car to work on it. I'll keep you updated! Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted June 29, 2006 Share Posted June 29, 2006 I'll be watching for your post, love a good mystery Quote Link to comment Share on other sites More sharing options...
MonteCarloTerp Posted July 9, 2006 Author Share Posted July 9, 2006 Replaced a partially melted spark plug wire, a melted vacuum line (to the heater valve), and checked the motor mounts (they are fine). The symptoms seem to be getting worse. I fired it up, and tried to back out of the driveway. More shaking/vibration than ever. RPMs dropped all the way to 300-400 when tried backing out in reverse (almost stalled out), so I didnt take her anywhere. At this rate, she won't run at all pretty soon. Jon Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted July 10, 2006 Share Posted July 10, 2006 only thing I can think of doing is to disconnect it from the trans and see how the engine runs Quote Link to comment Share on other sites More sharing options...
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