The Ford Barn

Junknshit · 11-12-2011, 01:30 PM

I have a 56 Merc with a 302/C-4. Originally I did a 289 early C-4 swap, then picked up a low mile 302/C-4, swapped it in, and went thru the "oops it shifts backwards" thing with it, solved that, wore out the 302 and was getting ready to pull it for rebuild. I had a 401 Buick nailhead that a friend wanted, and he had just picked up an F-1 pickup project that came with a fresh 302/fresh C-4 and tradedit to me for the nailhead. Well, it is in, running and driving. It shifted like the early C-4 so I again reversed the linkage. Someone had banged the tail housing and it was ovaled where the seal goes in and an ear was broken off of the mount. I changed out the tail housing with my old one. That made for two vents in the tranny, but tranny guy said it wouldn't hurt as long as there was a vent. Also, this new tranny doesn't look like it comes apart at the bellhousing (no seam, but looks like it would have the bolts inside the housing) As the engine block had been smoothed out and everything was done real clean, I suppose the seam could have been filled for clean looks before painting.

My problem is that I can drive it no problem, but after being driven 40 or 50 miles and parked it leaks fluid. It has to set for a while before it leaks, and it leaks considerable amount of fluid. Enough to run out from under the car, and I don't mean trickle out from under it. There is no sign of fluid anywhere on the underside of the car, so I don't think it is leaking while driving it. I can't see anywhere that it is running down or dripping out of the tranny. I do not know if the dipstick is the correct one, but it is the one that came with the unit to me. The end is broken off of the dipstick. The top end that is curled. Could I not have a C-4, or the wrong dipstick? Fluid is not coming out of the top of the tube, (or at least the tube is dry) and is not coming out around the bottom. Sure got me and my son stumped.

Sorry, I got it in the wrong forum I think.

COE Dan · 11-12-2011, 01:50 PM

First, I'd repost this on the late V-8 section and you might get a few more hits...here's my take though...

In addition to my flatheads, I have 66 Falcon with a 289/C-4 combo. I've had 2 trans in the car, both have been rebuilt over the years and both leaked before and after the rebuilds. Obviously, they leaked less after the rebuilds but still you would get occassional drips but no floods.

A couple things to note:
1) You mentioned you traded out the tail housing...did you replace the yoke that connects the trans to the driveshaft? My yoke needed replacement since the exterior shaft had worn visibly out-of-round and a significant amount of fluid would leak or bypass the seal both in operation and sitting.

2) Depending on your torque converter and the valve body, different C-4s have different fluid quantities. I overfilled mine and after operation for the first month, it would occassionally bubble an ounce or two out of the front breather. I'd have to check but mine might have a front and rear breather as well.

3) I'm not aware of different dipsticks for the C-4 but that doesn't mean they don't exist.

4) The last place I'd check for leaks is where the dipstick tube inserts into the trans housing. It is merely a force fit (no threads) and it's held in place by the flange that attaches beneath one of the bell housing bolts. Where the tube inserts into the housing there is an o-ring. If this o-ring is pinched or missing, you can get significant leakage when sitting.

Hope this helps

COE Dan

George/Maine · 11-12-2011, 02:19 PM

The c4 will have a removable bellhousing if filled in could be leaking there.Dip stick guess in pan about 2 inches.that seal sometimes leaks there.Loose bolt bellhousing,and front seal in trans.

Junknshit · 11-12-2011, 02:52 PM

Thanks for quik replies.

Not leaking around dipstick top or bottom.
Not leaking around converter.
Not leaking around case where joint should be.
Can't find any wet or damp spots on case or pan anywhere.
Can't find any drips anywhere.
No wetness anywhere under bottomside of car from blowing back.
But boy does it leak.
If I park it and check an hour or two later, nothing, tomorrow morning is a different story, much oil. Might have to camp out on shop floor. It's almost like it is all coming out in short time, like it might be under pressure.
Throw a bunch of oil dry down, let it soak, clean it up, jack up car, all 4 corners, no more oil comes out, and no drips anywhere.

Beginning to think maybe one of my deceased relatives didn't like me. ;<}

George/Maine · 11-12-2011, 08:26 PM

I think you have to much trans fluid,the convertor is draining down.
They always say check when running.
Check your stick make a mark 1" above casing try that if your stick isn,t right.When it drains down see were level is next day.

TJ · 11-13-2011, 11:18 AM

Sponsored Links (Register now to hide all advertisements)

After it sits the converter drains back into the pan and raises the fluid level. Check around the universal joint to see if it is wet back there. Could be leaking from the yoke or around the speedo cable..

Chris Nelson · 11-13-2011, 12:40 PM

I had a similar problem with my 36 cabriolet when i put in the 48 flathead and the c-4 combo. It leaked right away from the back of the tail shaft. I changed the seals and it still leaked, so I got a double lip seal and it still leaked. I found that the housing has porosity and is leaking right through the casting. I chased every spot that looked like it was leaking with J B Weld and that stopped the problem. It makes the tail shaft look a bit lumpy, but it doe not leak. I spoke to Gene Benson at Flat-O-Products and he said that they have experienced some C-4s that had porosity problems. Not frequent, but just the same, it is possible that you have one of these.

George/Maine · 11-13-2011, 04:34 PM

I looked at a Locker dip stick and were the tube bottoms out on the casting down from there 3/4 to 1 inch is the full mark NOTE that when running.

Junknshit · 11-14-2011, 02:43 AM

Thanks for all the replies guys. I'll check the dipstick, don't know how many different ones they made for C4s. I don't think it would be porosity because nothing is even damp anywhere on the trans or under the car, let alone wet. Nothing around yoke/seal, pan, dipstick tube, or anywhere on or around tranny. Nothing on bottom of car at all. I still don't know where fluid is coming out. Have to add fluid to make car move every second time this happens. Might put old tranny back in, SOON.

George/Maine · 11-14-2011, 11:11 AM

Now that you mention it there is a Pan fill,and a case fill.I would guess its leaking from the trouque convetor seal,or the gasket on pump.If leaking there it must be oil coverd under car if driving at high speed.The heat my stop it from leaking ,when cools off it leaks.

Frank The Plumber · 11-15-2011, 05:24 PM

Possible that the O ring on the end of the dipstick has squared or torn. Possibly the same at the speedo cable connection. Possibly the o ring seal that is within the shifter arm mechanism, a pia to swap. Possibly the seal that the converter uses to seat into the trans, you have to prelube that with a bit of trans fluid before you seat those home or she will take a nibble out of the seal. Could also be the vac modulator seal. Ain't these things a pain in the butt? I don't think I've ever had one that didn't leak and the one I did I blew to kingdom come racing. Now that was a leak. Put a clean sheet of brown paper under her and see if you can locate the exact scene of the crime.

11-12-2011, 01:30 PM	#1
Junknshit Banned Join Date: Oct 2011 Location: Wash. Posts: 233	C-4 ?? Problems. I have a 56 Merc with a 302/C-4. Originally I did a 289 early C-4 swap, then picked up a low mile 302/C-4, swapped it in, and went thru the "oops it shifts backwards" thing with it, solved that, wore out the 302 and was getting ready to pull it for rebuild. I had a 401 Buick nailhead that a friend wanted, and he had just picked up an F-1 pickup project that came with a fresh 302/fresh C-4 and tradedit to me for the nailhead. Well, it is in, running and driving. It shifted like the early C-4 so I again reversed the linkage. Someone had banged the tail housing and it was ovaled where the seal goes in and an ear was broken off of the mount. I changed out the tail housing with my old one. That made for two vents in the tranny, but tranny guy said it wouldn't hurt as long as there was a vent. Also, this new tranny doesn't look like it comes apart at the bellhousing (no seam, but looks like it would have the bolts inside the housing) As the engine block had been smoothed out and everything was done real clean, I suppose the seam could have been filled for clean looks before painting. My problem is that I can drive it no problem, but after being driven 40 or 50 miles and parked it leaks fluid. It has to set for a while before it leaks, and it leaks considerable amount of fluid. Enough to run out from under the car, and I don't mean trickle out from under it. There is no sign of fluid anywhere on the underside of the car, so I don't think it is leaking while driving it. I can't see anywhere that it is running down or dripping out of the tranny. I do not know if the dipstick is the correct one, but it is the one that came with the unit to me. The end is broken off of the dipstick. The top end that is curled. Could I not have a C-4, or the wrong dipstick? Fluid is not coming out of the top of the tube, (or at least the tube is dry) and is not coming out around the bottom. Sure got me and my son stumped. Sorry, I got it in the wrong forum I think. Last edited by Junknshit; 11-12-2011 at 01:36 PM. Reason: Add to

11-12-2011, 01:50 PM	#2
COE Dan Senior Member Join Date: May 2010 Location: Now in Wichita, KS Posts: 251	Re: C-4 ?? Problems. First, I'd repost this on the late V-8 section and you might get a few more hits...here's my take though... In addition to my flatheads, I have 66 Falcon with a 289/C-4 combo. I've had 2 trans in the car, both have been rebuilt over the years and both leaked before and after the rebuilds. Obviously, they leaked less after the rebuilds but still you would get occassional drips but no floods. A couple things to note: 1) You mentioned you traded out the tail housing...did you replace the yoke that connects the trans to the driveshaft? My yoke needed replacement since the exterior shaft had worn visibly out-of-round and a significant amount of fluid would leak or bypass the seal both in operation and sitting. 2) Depending on your torque converter and the valve body, different C-4s have different fluid quantities. I overfilled mine and after operation for the first month, it would occassionally bubble an ounce or two out of the front breather. I'd have to check but mine might have a front and rear breather as well. 3) I'm not aware of different dipsticks for the C-4 but that doesn't mean they don't exist. 4) The last place I'd check for leaks is where the dipstick tube inserts into the trans housing. It is merely a force fit (no threads) and it's held in place by the flange that attaches beneath one of the bell housing bolts. Where the tube inserts into the housing there is an o-ring. If this o-ring is pinched or missing, you can get significant leakage when sitting. Hope this helps COE Dan

11-12-2011, 02:19 PM	#3
George/Maine Senior Member Join Date: May 2010 Location: Mid coast Maine Posts: 1,878	Re: C-4 ?? Problems. The c4 will have a removable bellhousing if filled in could be leaking there.Dip stick guess in pan about 2 inches.that seal sometimes leaks there.Loose bolt bellhousing,and front seal in trans.

11-12-2011, 02:52 PM	#4
Junknshit Banned Join Date: Oct 2011 Location: Wash. Posts: 233	Re: C-4 ?? Problems. Thanks for quik replies. Not leaking around dipstick top or bottom. Not leaking around converter. Not leaking around case where joint should be. Can't find any wet or damp spots on case or pan anywhere. Can't find any drips anywhere. No wetness anywhere under bottomside of car from blowing back. But boy does it leak. If I park it and check an hour or two later, nothing, tomorrow morning is a different story, much oil. Might have to camp out on shop floor. It's almost like it is all coming out in short time, like it might be under pressure. Throw a bunch of oil dry down, let it soak, clean it up, jack up car, all 4 corners, no more oil comes out, and no drips anywhere. Beginning to think maybe one of my deceased relatives didn't like me. ;<}

11-12-2011, 08:26 PM	#5
George/Maine Senior Member Join Date: May 2010 Location: Mid coast Maine Posts: 1,878	Re: C-4 ?? Problems. I think you have to much trans fluid,the convertor is draining down. They always say check when running. Check your stick make a mark 1" above casing try that if your stick isn,t right.When it drains down see were level is next day.

11-13-2011, 11:18 AM	#6
TJ Senior Member Join Date: May 2010 Location: Napa,California Posts: 6,035	Re: C-4 ?? Problems. Sponsored Links (Register now to hide all advertisements) After it sits the converter drains back into the pan and raises the fluid level. Check around the universal joint to see if it is wet back there. Could be leaking from the yoke or around the speedo cable..

11-13-2011, 12:40 PM	#7
Chris Nelson Senior Member Join Date: May 2010 Location: Poulsbo, WA. Posts: 356	Re: C-4 ?? Problems. I had a similar problem with my 36 cabriolet when i put in the 48 flathead and the c-4 combo. It leaked right away from the back of the tail shaft. I changed the seals and it still leaked, so I got a double lip seal and it still leaked. I found that the housing has porosity and is leaking right through the casting. I chased every spot that looked like it was leaking with J B Weld and that stopped the problem. It makes the tail shaft look a bit lumpy, but it doe not leak. I spoke to Gene Benson at Flat-O-Products and he said that they have experienced some C-4s that had porosity problems. Not frequent, but just the same, it is possible that you have one of these.

11-13-2011, 04:34 PM	#8
George/Maine Senior Member Join Date: May 2010 Location: Mid coast Maine Posts: 1,878	Re: C-4 ?? Problems. I looked at a Locker dip stick and were the tube bottoms out on the casting down from there 3/4 to 1 inch is the full mark NOTE that when running.

11-14-2011, 02:43 AM	#9
Junknshit Banned Join Date: Oct 2011 Location: Wash. Posts: 233	Re: C-4 ?? Problems. Thanks for all the replies guys. I'll check the dipstick, don't know how many different ones they made for C4s. I don't think it would be porosity because nothing is even damp anywhere on the trans or under the car, let alone wet. Nothing around yoke/seal, pan, dipstick tube, or anywhere on or around tranny. Nothing on bottom of car at all. I still don't know where fluid is coming out. Have to add fluid to make car move every second time this happens. Might put old tranny back in, SOON.

11-14-2011, 11:11 AM	#10
George/Maine Senior Member Join Date: May 2010 Location: Mid coast Maine Posts: 1,878	Re: C-4 ?? Problems. Now that you mention it there is a Pan fill,and a case fill.I would guess its leaking from the trouque convetor seal,or the gasket on pump.If leaking there it must be oil coverd under car if driving at high speed.The heat my stop it from leaking ,when cools off it leaks.

11-15-2011, 05:24 PM	#11
Frank The Plumber Senior Member Join Date: May 2010 Posts: 693	Re: C-4 ?? Problems. Possible that the O ring on the end of the dipstick has squared or torn. Possibly the same at the speedo cable connection. Possibly the o ring seal that is within the shifter arm mechanism, a pia to swap. Possibly the seal that the converter uses to seat into the trans, you have to prelube that with a bit of trans fluid before you seat those home or she will take a nibble out of the seal. Could also be the vac modulator seal. Ain't these things a pain in the butt? I don't think I've ever had one that didn't leak and the one I did I blew to kingdom come racing. Now that was a leak. Put a clean sheet of brown paper under her and see if you can locate the exact scene of the crime.