Oil Cooler Cracking

[cobralee]

I'm using B&M's transmission cooler (I think #74235 polished aluminum) to cool my engine oil at the front grill but I get a crack in it about once a year. I'm on my 6th cooler. B&M states they use it on their off-road vehicles without a problem. I'm thinking it's the constant oil pressure that is the problem. I'm using 20-50w oil.

Anyone experience the same problem?

Thanks,

Ron

[DAVID GAGNARD]

Originally Posted by cobralee

I'm using B&M's transmission cooler (I think #74235 polished aluminum) to cool my engine oil at the front grill but I get a crack in it about once a year. I'm on my 6th cooler. B&M states they use it on their off-road vehicles without a problem. I'm thinking it's the constant oil pressure that is the problem. I'm using 20-50w oil.

Anyone experience the same problem?

Thanks,

Ron

Probably the way it's mounted,not the coolers fault....there is a lot of vibration.....never had one crack on my race car in 8 years....when mounting mine, I take some old rubber bushing from some old shock absorbers and slice them in half for the thickness and use them between the cooler and whatever it's mounted to, gives it a little "play" for twist and vibration.....

David

[cobralee]

Thanks David..I had the same thought last time I installed mine but used alot smaller rubber washers....so this time I'll try the heavier duty washers.

Are you using the same type of cooler?

Ron

[DAVID GAGNARD]

I've used 5 different oil coolers,using a auto trans oil cooler off a 2010 Ford F-150 now........
I think the coolers are of good construction, but vibration and flex will kill any cooler eventually.......

I'm not sure, I think I have used a B & M before....

David

[cobralee]

Thanks again.

Ron

[lovehamr]

Something to consider is that modern trans coolers seem to be designed for much less viscous fluid to be passing through at a lower pressure. Just observing the transfer tubes it looks like they are a good bit smaller than a cooler designed for engine oil, especially the weights of oil that most of us with dinosaur motors tend to run. It would be interesting to measure pressure loss across the cooler just to determine what sort of restriction the coolers of different designs would have with different oil weights.

In other words David, I know you got that cooler off of the hydraulic system of a front end loader, so go put the dang thing back and get a proper cooler! I’m sure the construction company would like to have it back as well. Frikin Cajuns man!

[mreid]

What size lines ae you running to/from the cooler? Tranny and oil coolers are two different animals.

[vector1]

tranny cooler is designed for thin transmission fluid and no pressure, just a return system. wrong application imo.

[DAVID GAGNARD]

In other words David, I know you got that cooler off of the hydraulic system of a front end loader, so go put the dang thing back and get a proper cooler! I’m sure the construction company would like to have it back as well. Frikin Cajuns man!
0

Dang Steve,you got me on that one....The front end loader was junked out,so they'll never miss it!!!!!

What size lines ae you running to/from the cooler? Tranny and oil coolers are two different animals.

12AN, yes they are to an extent,some are so close in design,you can't hardly tell the difference, I'll be posting photos later, and many top companies advertise their coolers as for use with either engine oil or transmissions!!!!!!!

David

[DAVID GAGNARD]

These are the oil coolers I've tried and the results. The car is a 65 Mustang road race car with a 331 cu in stroker, making about 500 hp, running 15/50 Mobil 1 synthetic oil. My normal rpm range while on track is from 3000 to 7000 rpms......

[IMG]url=http://www.clubcobra.com/photopost/showphoto.php/photo/77843][/url][/IMG]
This is a "headered" engine oil cooler, it is the least effective,but does offer great flow thru the cooler becasue of the bigger tubes, problem is, the oil flows too fast thru the cooler to cool it down to any degree..I have a temp gauge in the oil pan and one coming out of the cooler as it goes to the filter,giving a reading of the "cooled" oil before it goes back into the engine. This particular cooler would start out with about a 15 degree difference,during the course of a 30 minute race, that difference would drop to about a 5 degree difference!!!!!!!

Insert Photos and Images
[IMG]url=http://www.clubcobra.com/photopost/showphoto.php/photo/77839][/url][/IMG]
This is the next cooler I tried, it is a single pass engine oil cooler, somewhat better, but still not enough. The tubes are large for flow, but I think that also hurt it's cooling capacity, with this cooler I would see no more than a 10 degree drop in oil temp....
David

[DAVID GAGNARD]

Then I switched to this engine oil cooler:

this is the same type used in NASCAR,in fact I bought it used from a NASCAR team.... Almost identical to your average transmission oil cooler... It worked better than the two above, but still not good enough for my application, it was just too small in size.....

Then I saw this one:

[IMG][url=http://www.clubcobra.com/photopost/showphoto.php/photo/77840]

It's off a 2010 Ford F-150 Super Crew truck,it's the trans. oil cooler,it was free, so I tried it and guess what,it works... It is exactly twice the size in square inches as the NASCAR cooler and has the same size inlet/outlet and almost identical size "plates".....
with this cooler I now have a 20 to 25 degree difference in oil temp, which I needed as I have run oil temps of 250 to 270 degrees with the other coolers. Now my oil temp stays in the 210 to 225 range!!!!!!
With this cooler I have about 8 psi less oil pressure across the rpm range than without any cooler.....
here is a pic of the two coolers side by side for size comparison....

[DAVID GAGNARD]

Now,with all that said and done, I have a very similar motor in my street car, another 65 Mustang. Both engines have the same identical rotating assy,(forged crank/rods/flat top pistons), both have aluminum heads and intake,the race car uses a single plane intake and solid roller camshaft, the street car uses a dual plane intake and hydraulic roller camshaft. The street engine makes about 400 hp as opposed to 500hp for the race engine... The normal operating rpm range on the street car in normal driving is from 1500 to 2500 rpms....
Both engines have the exact same Canton 8 quart road race oil pan, the street car has no engine oil cooler.Normal city/highway driving, my water temp stays on 180 and my oil temp (sender is in the pan) stays on 180 also.....Once fully warmed up, if I do any "spirited" driving (shifting at 6000rpms and such) the oil temp will slowly climb to 200 to 220 degrees depending on how long I drive the car hard. I can't ever remember seeing oil the oil temp above 220, which is still fine...and this is with NO oil cooler...even with the oil temp at 220, a few minutes of highway cruising brings it right back down to 180......
So, basically street driven cars do not need an oil cooler,IMHO of course...

In the last 4 or 5 years I've seen a number of the top racers going to oil to water coolers. These are almost identical to the radiators of the 70's and 80's cars where the trans. lines screwed into one of the radiator tanks and the trans. cooler was in the tank. They claim the oil comes up to operating temp a lot quicker (which is a good thing) and the oil temp stays more consistant and does not fluctuate as much...These custom built radiators generally start out at about 750 bucks and go to a 1000 bucks depending on the size and car, this I know, cause I checked into them....
I use what works for me in my application and so far,so good, been racing this car for 8 years now....
and that's the story I'm sticking to.....

David