Guest alphamale1906 Posted November 2, 2009 Share Posted November 2, 2009 I have a TH350 that I cannot get out of gear or keep from stalling at stops. As long as I have the car in nuetral or am moving, I'm okay. As I approach a full stop, inevitably the engine bogs down and shuts off. Is it the torque converter or could there be some other culprit? I don't have the TV cable attached, but didn't think that would make any difference. However the trans is from an 84 El Camino and according to the haines manual the cable also controls line pressure in addition to detent and other down shifts. I don't have any fluid coming through the modulator so I assumed that was okay. Is there an easy trouble shoot or will replacing the torque converter be the way to go. Quote Link to comment Share on other sites More sharing options...
Guest alphamale1906 Posted November 2, 2009 Share Posted November 2, 2009 I'm with you on the kick down (detent) cable. That's what I've always refered to them as, but the haines manual called it that (for 1980 and later TH350 transmissions, so I went with it). I've triple checked all of the manifold and carb surfaced and no leak there. I thought that was the culprit, so I pulled the intake off, cleaned it and resealed it and still the same issue. I've triple checked the valve lash and still the same problem. I can get the car to idle just fine, but under load.....it shuts off. I have yet to jack the rear wheels off to see if a light load will stall the engine, but I'll try that next. Quote Link to comment Share on other sites More sharing options...
CrazyDavey Posted November 2, 2009 Share Posted November 2, 2009 Xavier, I can't quite get a clear picture of what is happening. Based on your first description is it like a stick car when you stop and don't push in the clutch? Or does it come to a stop okay but just won't idle.... Quote Link to comment Share on other sites More sharing options...
Andy's Auto Posted November 2, 2009 Share Posted November 2, 2009 My question is what cam are you running? Andy Quote Link to comment Share on other sites More sharing options...
Guest 72yellowmc Posted November 3, 2009 Share Posted November 3, 2009 bump your timing up a couple of degrees Quote Link to comment Share on other sites More sharing options...
kc8oye Posted November 3, 2009 Share Posted November 3, 2009 yet again, Haynes is WRONG *sigh* those books should not be allowed to be published with so much mis-information in them. TH350's never had "TV" cables. .they had "kickdown" cables. it controls when the trans kicks down when you stuff your foot into it.. it also has some control over all upshift points, but not a whole lot. TH 700R4's and 200-4R's used TV cables, to those trans it is VERY critical they are hooked up and adjusted correctly. Does this TH350 have and electrical connector on the driver's side? it will be a small square 4-pin connector facing upwards toward the floor pan just over the top of the oil pan rail, just behind where the shift linkage hooks up... If you have a TH350 with a lock-up torque converter and the converter is being kept locked up, that would cause the same problem... Quote Link to comment Share on other sites More sharing options...
Guest alphamale1906 Posted November 3, 2009 Share Posted November 3, 2009 Funny, I guess Haines goes with the 80% accuracy rule. The motor was originally from a 69 Camaro. Nothing hot (i.e. like a 30-30 cam). I think it was a lower performance motor. I'll try to bump up the timing, but I'm around 34 degrees total timing now, so not sure how much more room I have to advance it. As it stands, it fires up and idles well. However, upon dropping it in gear....the motor slowly stalls out. If I fire her up, then drop it in drive and go...Then she'll stay running as long as I'm gassing her. But, if I come to a full stop, then she'll conk out. I'll crawl under her tonight to see about the electrical connector. Quote Link to comment Share on other sites More sharing options...
Guest 72yellowmc Posted November 3, 2009 Share Posted November 3, 2009 As it stands, it fires up and idles well. However, upon dropping it in gear....the motor slowly stalls out. If I fire her up, then drop it in drive and go...Then she'll stay running as long as I'm gassing her. But, if I come to a full stop, then she'll conk out. FLAT CAM! IMHO Robyn Quote Link to comment Share on other sites More sharing options...
stangeba Posted November 3, 2009 Share Posted November 3, 2009 I saw this one time, bad vacuum diaphragm in the power brake booster that caused a massive vacuum leak only when you apply the brakes. Try applying the parking brake (don't use the regular brake) then put it in gear. If it acts the same, the booster isn't your problem. Hopefully you have a properly working parking brake. I'd hate to see you run over someone. Good luck, Bruce Quote Link to comment Share on other sites More sharing options...
Sam (Bones) Posted November 3, 2009 Share Posted November 3, 2009 can you keep it running with the gas when you drop it into gear? if you can, it's in the engine Quote Link to comment Share on other sites More sharing options...
Guest alphamale1906 Posted November 3, 2009 Share Posted November 3, 2009 Man, a wiped cam would be worst! Anyway, I just crawled underneath and sure enough there is a 4 prong connector on the driver side. I guess that makes this a TH350C. I don't know if that means that the converter is locked up or not. Either way, whever I get this issued resolved, I guess I should hook up a switch so I can lock it up once in 3rd and up to speed. But, that's for when I resolve the first problem. I will put it on the lift this weekend to see what happens when the wheels are off the ground and she's in gear. I'll also bump up the timing to see if that at least gets me to the lift without having to push it. Quote Link to comment Share on other sites More sharing options...
Andy's Auto Posted November 3, 2009 Share Posted November 3, 2009 I believe an 84 Mullet would have a 700 R4 not a 350. Unless it was either 3.8 Buick powered or 3.8 Chevy V6. No, I am not that smart. I have AllData at my shop. Either way, they all use TV cables. But suspect you either have a leanness in your carb, or a vacuum leak somewhere. Booster possibly. Andy Quote Link to comment Share on other sites More sharing options...
monzaz Posted November 5, 2009 Share Posted November 5, 2009 What is the carb? Check the idle air bleeds for dirt. and also if it is a holley check the power valve. or pull the power valve and plug the power valve if the car runs with brake on then that was the culprit. Just more to check Jim Quote Link to comment Share on other sites More sharing options...
kc8oye Posted November 7, 2009 Share Posted November 7, 2009 ok, that's a good point.. let's make sure you don't have a 700r4... look at the shape of your transmission oil pan.. is it a nice basic square with one corner cut off? or is it all irregularlly shaped? i would agree with the guys tho.. it does sound like a worn out cam.. I had similar problems when I had two cam lobes wiped out. Quote Link to comment Share on other sites More sharing options...
Guest alphamale1906 Posted November 11, 2009 Share Posted November 11, 2009 Rechecked the transmission today. It is a Turbo 350C. The "C" designating a Turbo 350 with lock up converter. In addition, it has the 4 prong electrical plug on the driver's side. Also, the pan is an aftermarket transmission pan (let alone the missing corner common to TH350s,) which also has "Turbo 350" stamped on the bottom. Anyway, I put the rear wheels in the air and disconnected the power brake booster (just in case it was the source of a vacuum leak) just to see what would happen. I let the car warm up to operating temperature. The motor had very crisp throttle response and a good idle. Carb settings were fine. I proceeded to drop car into gear and the engine remained running with the wheels spinning. Started with car in drive...No problem. Dropped through gears 1, 2 and back to drive...No problem. Spun the wheels up to 25-30...No problem. As I applied the brakes and as the wheels came to a complete stop, the car stalled out. With brakes applied (but not stopping the wheels) the car ran. The slower the wheels spun the slower the rpms, but she never stalled out as long as the wheels were spinning (even if spinning slowly). I'm sure it's not the timing, as I am at the upper end of my starter's capabilities as far as cranking the engine over (I'm at least at 38 degrees total timing). I'll hook up a vacuum gauge this weekend to ensure that there is no chance of a leak, but is there anyway that the lock up could be stuck on? I'll pull the valve covers this weekend to see if there is any play since I set the lash and broke the cam in. I checked once breaking in the cam and the valve lash was still on from when I set them. Thanks again for all of the suggestions and help!!! I'll keep trouble shooting and post outcomes. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted November 18, 2009 Share Posted November 18, 2009 yep.. sounds like the torque converter has welded itself together Quote Link to comment Share on other sites More sharing options...
Guest alphamale1906 Posted December 11, 2009 Share Posted December 11, 2009 Thanks for all of the help! In the end, I decided to go a different route. I will be bolting up a 200R4 when I get the chance. I found a decent one locally on craigslist, and figired that highway travel wasn't terrible with the 350C but why walk away from an overdrive if available. Especially since I don't have to do any major modifications to get her to work. I'm going to keep the TH350C around and use it in something else someday (with a new TC). Thanks again for the help and comments. Quote Link to comment Share on other sites More sharing options...
kc8oye Posted December 18, 2009 Share Posted December 18, 2009 you will like the overdrive I have a 700r4 and with my rear gears and tires... I run 2250 @ 70mph in o.d my engine is SUPER happy right there Quote Link to comment Share on other sites More sharing options...
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