[engineer9]

My '62 Cat Slim Jim trans fluid goes down and at the same time the level on my engine oil dipstick goes up and the oil is tinted kinda red. This trans supposedly doesn't have a vacuum modulator, so how's the trans fluid getting into the engine oil pan?

[stevep]

The only way for trans fluid in a Slim-Jim equipped car can get into the engine oil is if the trans cooler in the radiator is cross-mixing and the head gaskets are bad.

Have you looked under the car yourself for trans leaks?

[Engine-Ear]

yeah I gotta say that's a new one on me, engineer9...if you asked me, ATF visible in your engine oil would have to be clouded (literally) by oil+water mixing it up...

See if you can get a bottle of oil dye from a service garage (the stuff that glows under a black light) and add it to the tranny.

SteveP, can you comment on whether this dye is available for automatic trannies?

[engineer9]

There are a couple of very minor transmission pan gasket leaks (drips), but nothing of the magnitude I have observed...down 2.5 quarts in about 50 miles! And engine oil level is up by roughly the same amount.

Trans cooler leak to radiator side sounds possible (since trans fluid pressure > radiator cooling water pressure), but if it were leaking in this direction, I would expect the radiator cooling fluid to also change color (like the oil has)....it hasn't, its still bright green with no sign of any oil-based fluids. And there has been no change in radiator water level.

Two recent compression tests returned normal results with no "low pressure" readings that would indicate a blown head gasket, either to atmosphere or between cylinders.

[stevep]

Matt,

There is a green dye for detecting trans leaks.

[stevep]

Originally Posted by engineer9

There are a couple of very minor transmission pan gasket leaks (drips), but nothing of the magnitude I have observed...down 2.5 quarts in about 50 miles! And engine oil level is up by roughly the same amount.

Trans cooler leak to radiator side sounds possible (since trans fluid pressure > radiator cooling water pressure), but if it were leaking in this direction, I would expect the radiator cooling fluid to also change color (like the oil has)....it hasn't, its still bright green with no sign of any oil-based fluids. And there has been no change in radiator water level.

Two recent compression tests returned normal results with no "low pressure" readings that would indicate a blown head gasket, either to atmosphere or between cylinders.

Sometimes the fluids do not cross-mix both ways with a bad internal radiator cooler.

Try disconnecting your trans cooler and install an external cooler and drive the car and let us know what happens.

[waubva]

Originally Posted by engineer9

My '62 Cat Slim Jim trans fluid goes down and at the same time the level on my engine oil dipstick goes up and the oil is tinted kinda red. This trans supposedly doesn't have a vacuum modulator, so how's the trans fluid getting into the engine oil pan?

Question to you engineer9.Did you somehow connect a vaccum line to your vent line on your Slim Jim?. I made this mistake thinking the vent was a vaccum modulator. The car smoked and I lost tranny fluid all the time.Look in these posts and find the one that says"Whats This". If you connected your vaccum line to this item,I belevie this is your problem.

[engineer9]

OK...I just checked for a vacuum line connection to the Slim Jim and found one kind of hidden away on the left side of the distributor. It is connected by hose into the branch of a tee. The run of the tee is connected to the intake manifold in front of the 2-bbl carb on one side and to the push rod cover on the other. The line down to the trans goes thru some kind of a small cartridge (same size as the fuel filter) that is clamped to the block and then runs along the left side of the trans and then goes up to the top of the trans and connects into the top about 12" from the end of the tailshaft.

I pulled the hose connection off the tee and there was some ATF coating the inside. The Hydramatic Trans Shop Manual clearly shows this line in a picture (Fig 32 on Page 38); however, nowhere in the manual does it describe it...not even in the "Removal of Transmission" section. Is this the "vent line"?

This car was originally sold in CA and this "vent line" and the tee connection to the vacuum line appears to be OEM; maybe it is something "special" for CA cars? Any '62 Cat owners out there in CA that have a similar vacuum connection on their Slim Jim?

The only time I get "smoke" out the exhaust is after the engine is warmed up and I accelerate from a stop. I'll disconnect it this weekend, plug the tee, and see what happens.

Stand by...

[Stuart]

That vent line on a Slim Jim shouldn't be connected to anything - the metal line is plugged into the top of the transmission case and then runs up to the back side of the engine to that fuel filter-looking thing by the distributor. However, the other end of that filter should just be open to the air. It has a small piece of U-shaped rubber hose on it, but it's not connected to anything else.

[stevep]

I was thinking the same thing about a vacuum line to the vent, but figured that the car would be smoking real bad, so I didn't post it!
It doesn't matter where the car was built, that line should NEVER be connected to a vacuum source. Someone probably thought that it was some kind of funny modulator.

But I really do not think that it will allow ATF to raise the motor oil level.

[Deadhead]

I thought of this too, but did not say anything.

There is no PCV system on a '62 right?

I wonder if it could happen after the car was shut off as the pressure was coming back down, sucking fluid back into oil at that time & not burning it? If trans was overfilled, it could make it more likely too.

You'd sure think there would be a lot of white smoke!

Sounds like with ATF inside the hose you could follow the trail. Let us know what happens to your oil level now.

[mviker]

Deadhead,

I'm pretty sure that Cali cars in 62 had a pcv valve. My old 62 Bonnie I had 20 years ago was apparently an east coast car. It had that giant vent tube that just drooled out under the car. I bought my 62 GP last year. It was a west coast car and had what looked to be an original pcv setup instead of the vent tube. I was kind of suprised when I saw it as I was expecting to see the vent tube. I'm fairly certain the pcv was stock or factory equipped.

[Engine-Ear]

From my experience, some of the Calif built cars (VIN letter S) had a PCV type of deal, but the vast majority were equipped with a 'highway pipe' or draft tube.

[mviker]

Well I'll be darned. I have an S in my vin. So it's not necessarily that the car is a California car, but the code. I wonder what determined a pcv car verses vent tube car.

Thanks Matt!

[Engine-Ear]

oops, I mighta missatated what I meant...

S = Southgate, Calif.

but S doesn't necessarily mean PCV.

To the best of my knowledge, the Calif. emissions debuted in '62, possible beginning Jan 1st 1962.

[mviker]

Ahh, ok. I'm understanding this a bit more now. So my car was indeed built in Cali. I figured the pcv was a California thing too, but part of me was scratching my head as I didn't think emissions came about until 1965 or 66. Interesting stuff. Matt, you're a bastion of knowledge! Thanks for the info!

By the way...sorry for getting off the topic here. Sounds like the trans question was answered though.

[Stuart]

I'm pretty sure I've seen indications in my reference materials that a PCV valve may have been available in 1961, but I don't recall if it was an option or something used in parts of California or what. I believe Matt's right about it being a regular production feature on California cars starting in 1962.

[engineer9]

Mystery solved...WAUBVA was right...some where along the 46 year history line of this car, someone connected the trans vent line to the PCV line. I disconnected it from the PCV line this morning, took it for a 20-mile test drive and several things happened: 1. trans fluid and engine oil levels stayed constant, 2. no smoke from exhaust when accelerating from a stop, 3. engine idles alot better and 4. transmission shifting has smoothed out considerably!

[mikediaz]

Glad to hear! that's an interesting one. Any plans to further rinse out the crankcase or anything of residual trans fluid or what? Might be a good idea but i've never tried to do so and wouldn't know where to start.

[Engine-Ear]

mviker, thanks...having a near-photographic memory has its upside now and then.

this taught me something for future reference! ... thanks for sharing the problem AND the solution!!!