I took my 69 CAS out for a long run today for the first time since the engine rebuild and conversion. At about 35 miles into the trip it started acting a little sluggish. I stopped and looked under the bonnet and all looked normal and was running quite sweet. I looked under the engine/transmission and all looked normal. There were no error lights showing on the speedo. I continued on to my destination just driving slower. When I got there I checked the engine compartment and underneath again but all look normal, so I shut it off. Thats when I heard the sound, wierd, a sound like boiling water. I opened the bonnet it again and with the engine off I could clearly hear the boiling sound coming from the ATF tank. When it cooled I check the volume and it was normal and the ATF was its normal red color.
Obviously the ATF FLUID TEMP SENDER IS NOT WORKING. What should I check to find the cause of the overheating fluid?
Thanks,
Jeff
Well, I have never heard of that before..
Was it filled up with DEXRON automatic transmission fluid.?
If it was filled with another type of ATF, it may not have the high temperature or flow features of DEXRON ATF...
I presume You checked the oil level in the engine.
The ATF should only overheat if the car is heavily loaded and going up a mountain road in DRIVE 2
then the light should go on which means to go to DRIVE 1
so, If Your car wasn't heavily loaded and You weren't going up a steep road...
only thing I can think of... is something restricting the flow of atf..??
strange that one...
Hoses the same size as original.. ? fittings the same size inside?
large hose for the return of ATF...?
The ATF was red? no frothing? no water in the ATF??
LEE
Yes, it is filled with Dexron
Oil level normal in both engine and ATF holding tank.
I had the hoses replaced with new and used the original fittings- so I don't know if they are the same as original. Can I purchase new hoses/fittings that are correct size?
ATF is solid red, no foam, not pink. No Frothing and no water
Hi Jeff
it may not be the hose itself, it may be a connection..
were the orignal fittings used on the hoses?
as if new fittings were used, one of th fittings may be restricting the flow of ATF..
I used to sell hydraulic hoses etc many years ago and the internal clearance in hose fittings was different in most different makers... even though the fittings are sized by the Inside Diameter
1/2 inch means the size of the hose is 1/2 inch... but the fittings vary in size greatly..
If the original fittings were used... then I can't come up with anything yet..
It definately seems that the ATF was NOT boiling or over heating.. was the correct color etc.
You would have noticed that the pressure hose is smaller than the return hose which is larger for an easy return of ATF.. into the tank..
Lee
Thanks, Lee.
All fittings are orginal, only hoses are new.
ATF was boiling, at least boiling sound and when I turned it off the ATF boiled out of the cap onto the ground.
I am going out of state for a week and when I get back I am going to take my fuel pump and pump fresh ATF into the system and see if any junk comes out. I also need to replace the temp sensor as it is not working.
Jeff
When you mentioned it boiling out of the tank out of the cap, did you actually touch the fluid to see how hot it was? The way you describe it makes it almost seem like the fluid was "whipped" into a froth, incorporating air. This will expand the fluid so it would overflow the container when stopped.
Quote from: Jeff54Griffin on 22 February 2012, 15:14
Thanks, Lee.
All fittings are orginal, only hoses are new.
ATF was boiling, at least boiling sound and when I turned it off the ATF boiled out of the cap onto the ground.
I am going out of state for a week and when I get back I am going to take my fuel pump and pump fresh ATF into the system and see if any junk comes out. I also need to replace the temp sensor as it is not working.
Jeff
Hi jeff
OK.. new hoses but original fittings so I don't think they are the problem..
and it was boiling.. or boiling sound and boiled out of the cap... onto the ground..
or was it aerated... air in the ATF..
something we hadn't thought of.... the pump...
was there enough ATF in the tank? so the pump was sucking in air?? from the tank..
as its really a sealed system.. I would take the ATF pump off and check it..
the gears can score the plate but the plate would need to be badly scored to lose pressure..
there is also a pressure relief valve in the pump. also check it to see if the spring has broken..
so, Your hoses may be OK... maybe a bit of gunk in the ATF??
but I'd check Your pump first...
Hoses and fittings should be OK... ?? unless a fitting has been damaged when being installed..
Banjo bolts.. fitted correctly? ATF pipes not damaged?? restricting the flow..?
I'll keep thinking
LEE in Australia
I was in error when I reported that my fittings were original. One is not, it is completely different than the other stock fitting. Is there somewhere I can buy a new set of hoses with stock fittings???
Jeff
Hi Jeff
I don't think they are available..
I have heard of people getting new hoses made up, even with new fittings
including the banjo bolts on the bell housing...
which I thought would have been the hard ones to match..
but as I said, change brands and they can be entirely different..
even though they fit OK.. but all the VW parts may have been special parts
with exacting holes in them.. made to do one job...
I'm guessing the inside of the "new" part may be restricting the flow of ATF.. can you tell me which part it is?
then again, it may be something else..
You will probably find a used hose on the samba..
with the original ends OK... and have it remade up...
the hoses are matched.. with the old ends.. and new ferrules used to hold them onto the hose.
or have the flow rate checked with it and the replacement hose You have..
I only know that the pressure side has small hoses and fittings and the return lines are larger so the flow of ATF
isn't restricted.. You can try running the engine with the ATF tank cap off...
and see what happens... although the return port there is close to the top of the tank neck
and may spurt ATF everywhere.. ??
I used hose clamps on the Pressure hose in the engine bay..
good quality hose clamps naturally...
cheers
Lee in Australia
It is the end of the hose that attaches to the bent (90 degrees) from engine pump. Other end is stock banjo.
What pressure should pump be putting out?
Jeff
Hi jeff
is that the hose that connects to the pipe that comes thru the tinware near the dipstick?
its a pressure hose and fitting. the fitting looks like a JIC hydraulic fitting, although I've never seen one exactly like that..
what happened to the original part? I was thinking it would have been a banjo bolt fitting that they replaced..
I could measure an original part and see if the hole in Yours is the same..
ATF Pump pressure is [can't find My favorite book with that info] couldn't find that info in any other books??
engine oil pressure is about 28psi and its higher than that , maybe 45psi , I'll keep looking for My book...lol
cheers
Lee in Australia
Hi Jeff
the ATF Pressure is 42.5 PSI ..
I found it in one of My albums
not a good pic of the fitting but is that the one?
cheers
LEE in Australia Now in Autumn [Fall] and having a hot summers day?? only had about 10 of these over summer??
(http://inlinethumb04.webshots.com/48323/1200953555050767931S425x425Q85.jpg) (http://rides.webshots.com/photo/1200953555050767931NkmUVV)
Yes- the one with the screw clamp on it. I am going to take it off and see what size hole it has.
Jeff
I undid the fitting and the hole is small-less than 1/8" with an abstruction at the hose end. Will not let a 3/32" drill through.
What size should this hole be???
Jeff
Hi Jeff
it should be about 7.5mm wide which is larger than 1/4 drill..
if You can get a 1/4" drill in there loosely then that should be OK
Glad You found the problem..
I presume that the ATF should flow at a certain rate all thru the system..
and then have no restrictions on the return... [which are OK]
cheers
LEE in Australia
Drilling it out today!
Thanks,
Jeff
I hope that fixed the problem
LEE
not yet Lee! After drilling out the line I blew out (in reverse) all of the oil lines to clean them and behold the ATF is all pink and foamy. I am begining to believe that my pump(not new) is wearing out and is turning the liquid to foam. Is this possible, probable?????? I am out of my relm here so just guessing. I don't want to put it back together until I have this nailed down. Any ideas??????
Thanks,
Jeff
Hi Jeff
I only know that water turns it pink, but maybe foaming will do the same??
although You can usually see the water in it.. I presume that air in the ATF would do the same..??
check the ATF pump pressure releif valve spring , hopefully it maybe broken {easy fix}[not enough ATF pressure]
or the relief valve piston has stuck in its bore.. [so not enough ATF pressure]...
its opposite the pressure outlet.. Mine has an allen key head and I've never taken it out...[lol]
the blockage in the ATF pressure line may have caused it..??
the pumps don't wear the steel plate much apart from a few score marks.
Running them with no ATF could cause scoring.. My original pump was scored a bit but worked perfectly.[on the steel plate]
and no wear on the alloy housing that I could see. the pumps I have now had no marks at all in the alloy...
cheers
LEE
(http://inlinethumb04.webshots.com/48323/1200953555050767931S425x425Q85.jpg) (http://rides.webshots.com/photo/1200953555050767931NkmUVV)
(http://inlinethumb46.webshots.com/50157/1177278516050767931S425x425Q85.jpg) (http://rides.webshots.com/photo/1177278516050767931oAgLdD)
Thanks, Lee.
My ATF pump plate has no scoring on it and I did replace all of the seals/gaskets before reinstalling it. The relief valve was stuck when I first removed it but cleaned the bore and piston/spring. I am going to get a pressure guage to check the pressure. Unless it shows higher or lower pressure than 42 lbs I am going to assume that the foam is not being produced in the pump.
I looked back in the archives and found a thread by Sean on how to properly replace the ATF which I am going to do. I ordered max purple ATF fluid (DexronIII) which I am going to try.
The hole in the fitting is almost 1/4" now. Can't go any larger with this fitting.
Jeff
Well I followed Seans post on how to flush ATF and it pumped out pink foam for several seconds and then eventually turned the regular deep red of the ATF, NO FOAM!
I took the car out for a short run and it felt more responsive. I pulled the return line from the holding tank and NO FOAM.
I will take it out tomorrow after work and give it a longer run to make sure it doesn't overheat.
Jeff
Well, Jeff
it sounds like the problem was the foaming ATF..
I don't think it would be able to get pumped, because it was aerated..??
I'm guessing of course.. ?? but sounds reasonable to Me...
so Maybe You have fixed the problem of too slow a flow of ATF..??
cheers
LEE
Hi Lee,
so far I think that the too small hole in the aftermarket fitting, less than an 1/8 inch, and the large diameter of the hose was causing the pump to work very hard to force the ATF through the restriction was producing the foam. The lack of enough fluid maybe caused it to overheat.
I know that before drilling out the fitting to 1/4" ID the return line to the tank was a foamy dribble. Now it is a good dark red flow.
I am taking it out tonight for a good long run to make sure, I'll let you know.
Jeff
Well, finally success!!!! Long run, about 30 minutes, and NO BOILING. Rechecked ATF fluid in tank and it is still dark red with no foam. I could actually touch the tank with my hand. So it appears that the problem was the very small hole diameter in the aftermarket fitting in the high pressure side. ;D.
Thanks for all your help.
Jeff
Great News Jeff
LEE