My Chinook motor dies when I put it in Drive

[Chinook400]

Hi It's my first time on here so I sending this out in search of a little help.
I have a Chevy 400 with a turbo 350 transmission.Every thing was fine running and driving good.
I pulled up to a stop sign and it died.So I put it in park and it started right up.I put it in drive and it died again and again and again.Finally I one foot on the brake and one on the gas made it home.
Now I have been all over the web and every thing i read says i have a vacuum leak.I have 19 to 20 on the vacuum gauge.I even replaced vacuum lines that were not really bad.I still have good vacuum.I can kill the motor if I chock it out with my hand over the carburetor.So I think that the vacuum is good.

The carburetor I resealed it a few months ago and of course I thought I screwed it up so I went back through it and did not find anything in the bowl or anything amiss.It was running and still runs just dies hard when I try to put it in drive or revers.

So I dropped the pan on the transmission and I found some burnt looking type clutch material.

Do you think that my transmission is locking up when I put it in http://67-72chevytrucks.com/vboard/i...ifdrive.:waah:

[geezer#99]

Quitting like that can mean a lack of initial timing.
What's your initial timing?

[Chinook400]

The timing on the air cleaner calls for 2 degrees before top dead .But I have set it at that and had it at eight through twelve and between. And Nothing changes dies or stalls hard when I put it in drive. You would think I could get it to at least try to move.
Do you think the forward gear clutches in the transmission could be causing this problem?
I did find burnt smelling black like clutch stuff in the pan with brass looking sparklers mixed in

[MountainGoat1966]

What is the engine RPM at when idling ?

[Zach079xxx]

I had a some what similar problem. Months ago, I was towing my lawn mower home from the shop and pulled into DD for a coffee break. I have a 350/350 and my temp was about 200-210. Pulled up to a stop sign and it died, had to brake/gas same time to get home. Only did it when it was fairly hot! (Engine temp). So fast forward, I pulled my engine and built it and installed a thumpr cam, great until put into park, killed it. Had to buy a 2500 stall converter and that solved it. Not sure of the cam before building.. I put a 180 thermostat in and it's never seen 200 since.

Try turning your idle up and see if that helps. I can't imagine you have the same problem I did, I basically got a new engine swapped in, and you did not. Let us know what happens

[Dead Parrot]

If the engine runs fine with the tranny in N or P, but dies if in a move it slot, could be the torque converter is locked up or nearly so. Is your TH350 one of the ones with the lockup converter? Does it die in reverse?

[turbosix]

Sounds like a lean condition on the idle circuit to me or a vacuum leak somewhere.

[N2TRUX]

To clarify, it runs just fine and revs freely while in park? It dies when you put it in gear? Sounds like transmission to me.

[rich weyand]

Things I would check:

1) Bad or wrong vacuum advance canister, or vac advance canister connected to ported rather than manifold vacuum.

2) Low initial timing setting.

3) Low idle rpm setting (should be about 700, which seems real high to someone used to setting up a stick shift). Should be about 700 in P/N, and 550 in D/R.

Read this: http://67-72chevytrucks.com/vboard/s...d.php?t=689321

[Chinook400]

Hello Chevy owners .I have adjusted my air full mix to the max vacuum on the gauge. I have about 2 1/2 turns out on each side. I have about 19 on the vacuum gauge when running at idle.

If I put my hand over the carburetor I can kill the motor if I choke all the air off . I have checked and replaced dam near all vacuum lines.

I have pulled the transmission and checked the torque converter and it seams to turn freely.All thought I am not a torque converter specialist.I talk with a local torque converter re builder he say he can test it on Monday.

I don't think that I have a over heating problem.This motor has a nice transmission cooler and a nice oil cooler and has never goon over 190 on the gauge.I did blow out the transmission cooler to be sure that the oil was flowing though it.

Has any one every had a turbo 350 lock up in drive and revers like this?

Before I pulled the trans to inspect the torque converter and look for trash in the transmission pan . I could rev the motor slap it in drive and the motor would die dead stall.

Like I have said before I have tuned this thing all over the pages and it does the same thing no matter were the timing and idle are set.

Is there any way to test the transmission with it out of the motor home?

[Chinook400]

Ya she dies hard in revers or any drive gear

[geezer#99]

Have you popped the distributor cap off and checked the weights aren't stuck?

[Chinook400]

Hay got A Question on the turbo 350 transmission .There are two different shaft sticking out were the torque converter goes.Should both of those shafts turn?

[turbosix]

Originally Posted by Chinook400

Hay got A Question on the turbo 350 transmission .There are two different shaft sticking out were the torque converter goes.Should both of those shafts turn?

I think you found your problem. The bigger shaft isn't supposted to turn it's a stator support. There is only one input shaft and it's the smaller or inner one.

[Chinook400]

Hi. The larger shaft does not turn.Just the smaller one with a hole down the middle.I am getting a education on transmissions and torque converters. I have made a decision to have the transmission rebuilt but I'm not convents that is my stalling problem.I still trying to figure out if this transmission will fail and do what it is doing.

I have a turbo 350 with a hole down the middle of the smaller shaft that goes into the tongue converter.Is this a lockup type converter? There are no pressure switches,but the is has a plug where some people say there should be.

I would like to know if I have a lockup type converter that can fail in a lockup and stall the motor stopped in drive or revers.

Thanks for any help.

[Zach079xxx]

Don't quote me on this, found this online. All I know is, I had such a hassle when building my tranny. I supplied parts for my build and I paid someone for labor. I asked what I needed, and it turns out he totally forgot telling me I have a lockup converter. I wish I could tell you how.. But this is all I got.

"A th350 lockup has a square female electrical plug on the side which a normal 350 doesn't."


Also found this.

[Chinook400]

Thanks I pretty sure I have a non lockup type 350 No electrical plugs or connections anywhere on the transmission.Control modulator on the right rear of transmission.
Thanks for your help

[jjzepplin]

I had one do this - it ended up being the vacuum modulator had failed. Also big smoke from the exhaust. Frightening til I found out it was 15 dollars to fix.
I am wondering about the trash in the pan of your trans ....

[cadillac_al]

I have never heard of a tranny doing this but I can't imagine what else it could be. 19" of vacuum, revs freely, then stalls when going in gear. The torque converter should still be pretty much free wheeling at idle. I guess something must be wrong there.

I had a big vacuum leak in my Caddy and the trans would bog the engine down quite a bit but not stall. I also think I still had good vacuum on the gauge with the big vacuum leak (memory is getting foggy). All I know is if you are sure there are no big vacuum leaks I would suspect the torque converter even though I have never heard of this before. I can't wait to find out what it is.