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Turbo 350 Problems after engine swap, PLEASE HELP

 
kludgemechanic
I love my Chevy Chevette!
Posts: 2
Joined: 10/12
Posted: 10/31/12 08:00 PM

So here is the scoop.

I helped my friend pull his 350 engine due to a bad cylinder and we had it bored and honed and we rebuilt the engine.

We installed the engine incorrectly due to lack of experiance. We installed the torque converter onto the flywheel first and then pushed it into the transmission. (Stupid I know).

When we had the engine install completed we tried to start the engine but it wouldnt turn over at all, which we finaly figured out was due to the toqrue converter not being seated into the transmission fully which put it in bind.

Later we pulled the motor again and we think we installed the torque correctly by putting it into the transmission first and then bolting the torque converter to the flywheel.

We took it for a test drive and it would shift from 1st to 2nd but wouldnt go into 3rd. My friend thought the engine wasnt running as good as it should because 1st gear didnt pull strong enough and he messed with the timming, carb mixture screws, carb floats, and the kickdown cable by himself. When I went back over to help him with the transmission not shifting into 3rd it would hardly pull at all.

It will go into gear in D, 1, 2, and R but it will barely pull itself. It seems like the engine is idleing pretty high but we cant tell for sure because the truck doesnt have a RPM gauge. When he puts it into D, 1, 2, or reverse the engine boggs down a whole lot. If the engine is not warm when he puts it into gear it will die. If he waits untill it warms up to operating temps and then puts it into gear it boggs really bad and if he gives it gas the engine wont increase very much in RPM's.

Im not sure where to start with this thing. I think that the transmission fluid is good but Im thinking that the dipstick reading is not 100% acurate due the the engine idleing too high (not sure if that would make the reading off or not)

We may have damaged the pump in the transmission when we installed the torque converter wrong but if we had I have heard from friends that the transmission whould make a whinning noise and we have never heard that. I also heard that if the pump was messed up that it would leak transmission fluid which its not. Plus it did work in 1st and 2nd gear when we test drove it once.

Please give me some ideas as to where we should start troubleshooting. Sorry for such a long post but I wanted to give as much detail as possible. Engine problems, Transmission problems, or both?

1969 Chevy 350. Turbo 350 Transmisson - no Lockout.

Thanks in advance.  

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waynep71222
I have an SS396 tatoo
Posts: 448
Joined: 03/12
Posted: 10/31/12 10:02 PM

you have probably destroyed the transmission front pump.. and also the torque converter..


torque converters can be had from torque converter rebuilders and a few transmission parts suppliers...  there are even a few transmission shops that can rebuild or will sell you an exchange converter..

you are going to want to examine this article for a few tips..  you will need some kind of manual that cover the TH350...  they used it for a lot of years...  from 68 to around 81 all over the GM lines..

http://www.circletrack.com/drivetraintech/ctrp_0809_th350_transmission_build/viewall.html  

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waynep71222
I have an SS396 tatoo
Posts: 448
Joined: 03/12
Posted: 10/31/12 10:22 PM

the torque converter number is probably
a  transtar B-35  
a west coast transtar C9.

uses 3 nuts and bolts to attach to the flex plate...


here is a short video on removing the front pump with one of the proper tools..

http://www.youtube.com/watch?v=rxiSoZdNfmM  

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redneckjoe69
I mow my lawn and find Chevys
Posts: 2337
Joined: 03/10
Posted: 11/01/12 04:10 AM

when you say you put the converter on the tranny first,...did you keep spinning it and pushing it back til you heard a clunk noise a few times?       you cant just simply slide the converter on and bolt up the engine.    this could be why your not getting 3rd gear?    the front pump could be broken as Wayne pointed out.
     if you didnt spin the converter on, id un-bolt it from the flexplate, then spin it by hand a few, full revolutions and keep pushing it backwards til it doesnt go back any more.    you might get lucky?  

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kludgemechanic
I love my Chevy Chevette!
Posts: 2
Joined: 10/12
Posted: 11/01/12 07:57 AM

Thanks for all of your input. We did turn the torque converter while we were pushing it onto the transmission but I think I only heard it click once. We will unbolt it first and spin it some more while pushing and see if it goes in further. Is there any way to test the front pump on the transmission to see if that is for sure the problem or do we have to pull it to tell?  

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waynep71222
I have an SS396 tatoo
Posts: 448
Joined: 03/12
Posted: 11/01/12 08:32 AM

Is there any way to test the front pump on the transmission to see if that is for sure the problem or do we have to pull it to tell?  

yes and no... you can check the line pressure... but you need a transmission pressure gauge set to do that..

this is a harbor freight oil pressure test kit..
Engine Oil Pressure Test Kit Item #98949  20/25 bucks
Pressure readings from 0-140 PSI and 0-10 bar
66" high pressure rubber hose


Image 12200

this is for checking ENGINE OIL PRESSURE.. but you get the idea.. usually transmission pressure testers have gauges about this range.. but also a 200 pound gauge as some of the pressures can PEG and ruin this 140PSI gauge.. the transmission pressure testers also have a longer hose.. but at this price.. you could buy 2 and connect the hoses..

you can check for flow at the cooler pipes... but thats not as good as tearing it down.. and inspecting..   were you able to click the links i posted...  and copy and paste the youtube 350 pump removal...   you can create 3/8-16 slide hammers to extract the pump body.. as the pump bolts are 5/16" and 2 of the drilled holes through the pump cover are threaded...

if the PUMP gears are broken...   you are probably going to have contamination in the valve body... as that is the next stop for the fluid flow..

you can get an ATSG techtran manual online for about 30 bucks..  in print or PDF..  TH350s rebuilds are also covered in most late 60s and 70s vintage chiltons manuals also.. be sure to check before you invest..

and anybody reading this ... don't try to pull a TH700/ 200-4R/4l60 pump without dropping the pan like is shown in the video..  you won't be happy...  

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76Skylark
Big Block power for the win
Posts: 868
Joined: 12/11
Posted: 11/01/12 10:49 AM

as for putting the converter on ALL the way you not only Hear the Steps on the trans shaft you can feel it.when the trans housing is seated against the block(bolted on) the torque conv. has a gap about as wide as a finger between it and the flex plate,you will notice this as you install the engine if they touch start wiggelin' the TQ and rotatin' it at the same time, it will go.  

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skyeking
I mow my lawn and find Chevys
Posts: 2738
Joined: 08/09
Posted: 11/02/12 03:58 PM

Hi POP!!  
skyeking

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pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 11/02/12 09:29 PM

I think in some way the front pump got hurt. It sounds as if it only builds pressure when the RPM is higher. It won't get it to the forward clutch assy.

Bob  

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pepsi1
I mow my lawn and find Chevys
Posts: 1718
Joined: 09/11
Posted: 11/02/12 09:32 PM

Hi Skyeking:
Are you in Hawaii? Watch those hula's there may not be what you think under them! Confused
Just drink the Lemonade Grin  Cool
Bob  

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