TH350 Problem: Too little fluid, bad filter, Murphy's Law?

FINALLY got my 50 on the road today with my old work comrade and fellow HAMBer ModelACitizen. He got here at 10am and we busted ass putting in brake lines and fittings, checking the timing and compression, and getting it moving.

Prior to the first ride, we discovered that more trans fluid had been lost than I had originally believed (as I was installing cooling lines, it repeatedly spitting up when the lines weren't installed, etc etc). It wouldn't even move when I put it into drive...SO we checked the fluid level, DOH....bone.....dry We started by tossing 2.5 quarts in it, and barely registered any fluid. I cranked it, put it into drive.....it moved well. Since the engine was cold, we let it warm up some and "drove" it about 50 yards down our little side road. I say drive....old folks move faster in their Rascals It ran well, but wouldn't shift due to the fact of no vacuum hooked up at that point. It finished strong and pulled back into the driveway without a problem.

SO, now we test the fluid level again, STILL not really registering. We put another 3.5-4 quarts into it. It begins to show signs of registering, so we creep down the road again....running well, shifts when I get up some speed. I slow down to turn it around in a little parking lot, and I go to gas it again and it starts to shudder....running like sh*t, I thought it was metal parts knocking, but Ehren (by FAR the car guy....) said it sounded more like sputters and backfires. It won't barely move when gas is applied, but idles fine. We end up having to pull it back to the driveway with my neighbor's truck

The more gas I gave, the worse it sounded. The only difference between the two drives was the added fluid and vacuum hose. We called it a day and vowed to ask around and get some input. Knowing squat about transmissions, I still have to say that it behaved like a stick shift when you're at a dead stop, on a hill (as we were) and try to get going in 3rd. Is it possible that after it shifted successfully, with no problems going down the hill, that the lack of fluid prevented it from shifting back correctly? I dunno...just an idea. Another idea I was given was that the filter may be bad, sucking fluid into the carb. I pulled the tube, sniffed it, squeezed it...no fluid. I'm compiling a list to begin going thru, so I look to you guys for valid thoughts.

I'll appreciate any and all *constructive* help or ideas....if you just throw down "It's toast", "you're f**ked", or any such worthless drivel.....don't even bother. I get enough of that from KillBillet.

THANKS guys!!!

 

You better keep adding fluid until it starts to register on the dip stick. My 200 4R has about a case of fluid in it! It's no 5 quarts like motor oil. It's much more for the tranny.
Dom

 

Yeah, that's the feeling I was getting after it took 5 quarts and showed nada

The last push up the hill, before I towed it back, I was giving it gas (not like crazy) and the more I pressed, the worse it sounded. Hopefully the tranny isn't shot. Worked fine before the vacuum hose was hooked up...go figure.

I should have known when we hit a streak of luck with the brakes (didn't have to do ANY redo's on the fittings....first time was the last time ) that Murphy's Law would come back with a vengeance!

 

OH...one last thing, didn't think it would affect it, but wanted to add. I *do not* have the kick down cable connected...didn't think that mattered except for OD.

 

Huh, the TV cable is a a little bit important too.. Which tranny you running? It has a lot to do with the shifting of the tranny.
Dom

 

DUH...forgot to post the trans type....it's a TH350 I fell so ignernt!

 

The trans takes alot more fluid than 6 quarts. Not 100% but I think like 12 quarts with a dry torque convertor. The kickdown on a 350 should only stop it from down shifting while moving if not connected...

 

Is it the one with a lock up converter ,Or just a kick down ,At idle bring the fluid up to level .

 

I'll pour it till it fills and see what happens! So do you think that fluid that low, or a problem with the vacuum line could cause an issue like that?

 

If its vacuum related it should have ran bad from the begining and not just all the sudden change.

 

The vac line will cause it to stay in gear longer. The signal is relevant to throttle position. Less vac=more load/throttle position will cause the transmission to stay in low gear longer. A TH350 with a standard pan and a small cooler will take 10-14 quarts of ATF. All that you have to do is have it running, add a quart, get in the car shift to reverse, drive and then back to park or preferably neautral. wipe the stick off and recheck.

The noise that you have explained does not sound good, but lubrication may help it. I would definatley give it a shot.

CJO13

 

Okay. when you are giving it gas and it's "starts to shudder....running like sh*t,", is the motor revving freely and the vehicle doesn't want to move or is cutting out and not picking up rpm's?

 

Ah, even though the vacuum source wasn't hooked up originally and it ran well?

Yeah, I didn't like the sound either. But it sounded more like it was coming from the engine, not the transmission. I tested the engine many times before ever engaging the transmission. I've carried it all over the RPM spectrum before taking it off the jackstands and putting it into drive. Hopefully that bodes well for the engine. It was weird as hell....and it's odd how it sounded ok before I hooked up the vacuum line

 

The motor is not revving freely. It's more like "cutting out and not picking up RPM's". Like I mentioned, it behaved like a manual trans, trying to start up a hill, from a stop, in 3rd or 4th.....the shuddering, sputtering, although it sounded more like backfires....had some OOMPH to it

 

doubt if that is your transmission then.

If by some odd ball chance it is, it would have to be something in the pump or converter trying to lock up and drag the engine down..... but then still it wouldn't cause a shudder, sputter or misfire.

I am thinking it's in the engine.

 

They do take quite a bit of fluid if they were dry. I'd have to go out and check but I think a bone dry one takes right around 12 quarts for the trans and converter. I think they usually take 3-1/2 quarts if you drop the pan on a trans that is full to the mark to change the filter. That is what I usually add before starting the engine and checking the fluid level after I change a trans filter on a turbo 350.

The turbo 350 will work ok with out the detent cable being hooked up but it will want to shift very early. like going into second about 10 mph and third about 20/25 under mild acceleration. Granny wouldn't know the difference but it doesn't do much for performance.

The vacuum issue could be caused by the vacuum line not being hooked to the modulator right or the modulator being bad to begin with. It may not suck fluid up through the hose right off the bat especially if the fluid is low.

 

The engine is the doomsday scenario. My buddy mentioned the term "spun bearing"......gave a description that I didn't fully comprehend other than it's ultra bad news. Would it just be coincidental that it happened after connecting the vacuum, then?

 

Ahh....I can check how it's hooked up, but it seemed straight forward, hooked it from the driver's side vacuum port on the front of my new Edelbrock and connected it to the port on the back of the filter.

However, would that, in any circumstances, cause this weirdness?

ADDED: Could it be one HELL of a vacuum leak elsewhere?

 

Poboy, You should check the fuel pressure. It sounds like you have two problems,not enough ATF and a fuel starved engine. Normal Norman

 

The vacuum line didn't have anything to do with it. I ma not saying you have a spun bearing, you could have a tuning issue + something else making the noise. It could be the pump or T,C, banging and but a tune problem making the engine run bad. I would drain the engine oil and look at the condition for metal contamination, even go as far as cutting open the oil filter.

If you see evidence of metal, I would pull the engine pan and check the rod bearings.

 

It sounds like it might be the shitty old Camshaft went flat scenario or a rocker arm came loose. Pull your valve covers and check the rockers and see if they are all in place, if that is well you might want to do a quick visual while someone cranks it over with the power to the Distributor unhooked adn see if all of the valves are opening approx. the same amount. I have had exhaust lobes go flat on a cam and it has caused performance issues pretty similar to the one that you have described. If you cannot get rid of the cylinder pressure on ehaust it pushes it into the intake causing a popping sound through the carb. The engine will basiocally miss on many cylinders when this happens. It acts like it is trying to F itself.
It would be a relatively cheap check. No parts involved just your time. In my case my time is not worth anything, but it hurts when you have to open the wallet.....

CJO13

 

FYI, that thing you're connecting the vacuum line to on the transmission is the vacuum modulator, not the filter. The filter is inside the transmission, you have to drop the pan to change it.

 

I went through this with my 727. On mine it turned out to be the way I adjusted the Ginie Shifter. I missed a small adjustment. Mine sounded like it was starting out in 2nd too. I burned the front clutch due to the slipping sound. I also just replaced a distributor in my wife's '66. When I hit the gas, it bogged and poped and sputtered... I took it to the guru for a small adjustment and she runs like a champ.

Sooo, that said, my $.02 is a timing/tuning issue with the motor and a fluid & shift linkage adjustment. Good luck with it either way.

 

Funny you reply, before I posted this, I did a search and found your thread. It shed some possible light on the situation I thought about the shifter early on, but since it shifted, I thought it was ok. I have a B&M ZGate shifter, and I followed the adjustment procedures in the instructions, but perhaps it still wasn't right. It shifts fine with the engine turned off, or at least it feels that way. When I cranked it, I noticed that it kind of "dragged itself" across park on its way to reverse, and that it shifted better if I skipped over the gear and came back sometimes. As I mentioned, the sound was awful. At first we thought it was metal knocking around it sounded so bad, but Ehren got out and listened, said it sounded more bog/pop/sputter/backfire from outside the car. Hopefully that's all it is, and that I didn't F up the trans I didn't take it over 1500-2k RPM...not sure if that will even matter

 

Sounds like your worried too much about a worst case scenario. Slow down and check one thing at a time and you will find it. Always start with the basics.

 

Make sure the vacuum line is hooked to the correct port. It MUST have vacuum at idle to that port. There's a port on most carbs that only get vacuum after the throttle is cracked open. That's the wrong one

 

Vacuum line is on the correct port, below the plate....the timed vacuum is going to the distributor.

I'm checking the rockers, trans fluid, shifter today......also the oil pump to see if that went bad.

 

Common correct precedure for checking ATF is with the engine idling at temperature, and your foot firmly on the stop pedal is to go through EACH gear/position, starting in park-reverse-neutral-drive-second-first and back again. I like to do this 2 times back and forth, deliberately stopping in each position and counting one two then move to the next position. Then stop in park or nuetral and check your level, engine still idling. Just how I was taught by a man who builds trans for a living and has for almost 40 years. Remember, a stock 12" converter will hold most of 2 quarts by it self.

 

That trans if bone dry will hold approx 11 1/2 - 12 qts of ATF depending on the cooler lines and size of the cooler itself.

 

Running a trans low on fluid is not good. You shortened the life of your clutches, or you may have burned them up or warped them. I managed to do this once with a leaker.......Didn't take very long. No symptoms other than crap in the pan.

I am not sure how low fluid may have damaged your convertor, however, I have had a shudder in the past due to a bad torque convertor. You may have galled the bushings/bearings on the input shaft?

I'm no trans expert, however, I have destroyed a few. It is the more expensive part of hot rodding in my experience..........