over heats when turned off. trans fluid climbing tube?

[bigbuc83]

I'm new to the older chevys. I've got an 86 k10 with 350 and 350 turbo trans. I've already replaced u joints and diff fluid and brakes and resealed intake.
A couple things it does that's weird to me is that when the truck is turned off coolant comes out overflow and temp is at 230. Driving its at 180. Over never seen this problem before.
Another thing it has going on with it is that the transmission dipstick tube starts filling with trans fluid. Almost like the pan is pressurizing and its coming up the tube. No its not over full. Initially it is in the hatch marks. And as it runs it goes halfway up the stick.
Thanks in advance for help

 

[foamypirate]

I'm new to the older chevys. I've got an 86 k10 with 350 and 350 turbo trans. I've already replaced u joints and diff fluid and brakes and resealed intake.
A couple things it does that's weird to me is that when the truck is turned off coolant comes out overflow and temp is at 230. Driving its at 180. Over never seen this problem before.
Another thing it has going on with it is that the transmission dipstick tube starts filling with trans fluid. Almost like the pan is pressurizing and its coming up the tube. No its not over full. Initially it is in the hatch marks. And as it runs it goes halfway up the stick.
Thanks in advance for help

Trans fluid should be at the hashmarks when warmed up and running, not when parked and cold. Not sure about the overheating after shutting the truck off though.

 

[bigbuc83]

Right. But we are talking like a 12" gain from cold. On no vehicle that I've seen has that been OK. An inch or 2 at most is the cold to hot gain. One time it starting squirting out of pan gasket. Not saying gasket isn't bad. But it is spontaneous and hasn't done since the one time

 

[MadOgre]

I would be taking the pan off to inspect the filter and replace it and gasket. Check the breather tube on the top of the transmission to make sure it is in good working order.

The coolant over flow and over heating could be a faulty thermostat with and or air pocket in the system. Take off the rad cap and idle it up to temp and ensure that the thermostat is cycling.

 

[MrMarty51]

Never overfill an automatic transmission, them rotating assemblies in there will cause the fluid to foam, right up the dipstick tube.
Drain it off, run until to operating temp, in park, should NOT be above the full mark. I run mine about 1/2 way between the add and full marks.
Install an overflow tube, bottle and an overflow radiator cap, that will catch the prestone while engine is warming then, suck it back in when it is cooling down, save You a bunch of money with a system like that.
Might be able to salvage yard pick one of those systems from an 87 to 91 suburban, might be a 90 too. then all You`ll need will be a new radiator cap.

 

[bigbuc83]

I was unable to find a vent tube last time I looked at it. I'll do a filter kit on it Sunday. As well as I will put a thermo stat in it and burp the system. Will check back in.

 

[Hoodbj]

I agree on the vent tube, I once got a r10 pickup for a few hours of work because the owner thought the transmission was out. It was burping fluid out the dipstick tube and actually caused a small fire when it hit the manifolds. The vent tube was clogged on the transmission, cleaned it out and all was good. I think it was a 700r transmission, I can't remember but the vent was on top of the transmission.

 

[chengny]

You probably won't be able to see it too good - unless you have a little tiny head and a really long neck:

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[Rule_So_Hard]

I understand that you're "Not supposed to" over fill the trans but I always have ran type F in my Chevy transmission and a half to a quart over full. I've never had an issue with foaming. Not saying it couldn't happen or doesn't. Just saying in my personal experience.

 

[bigbuc83]

I was able to get a few to pull truck on shop and locate vent. It was on driver side and I had to dig the mud off the case to find the hole. It had no tube attached to it. Any ideas where to find a tube? I'm also going to run it into the cab so this doesn't happen again.

 

[chengny]

Sorry man - for posting images of the wrong transmission. Don't know where I got the idea you had a TH400.

But as you found out, the vent on a TH350 is on the driver's side - for a TH400 it's on the RH side.

 

[bigbuc83]

its all good. I resolved the overheat issue. I had previously replaced the cap and thermostat I had remembered. but what I also had to do when I bought the truck was bend the overflow nipple up. looked like it was drop on end. well today I revisited this area of the radiator and found that the neck lip itself had been bent up. it was causing the inside seal to not reach the lip inside the neck of radiator. while running it is fine because the waterpump essentially draws a vacuum on the system on one side. when turned off it all exsists the the overflow because its not sealed.
my fix was taping down on the outer lip and sanding it flat. so far its so good