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SO my oil cooler has decided to start giving me trouble. I just got my engine rebuilt and I assume since it's functional now it put extra stress on the cooler which decided to start leaking on the left side ( facing the windshield) . also id greatly appreciates any help you guys can give me, iv fixed a lot of crap on this car off advice from here and met a lot of great people.
Just so you guys know what I have done to the engine. I have a top trim Automatic.
Engine rebuild with less than 300 miles
Emissions delete ( yes I'm in Cali )
Upgrade to FD exhaust system
Restored radiator .
Issues in having of now, Leaking oil cooler
Carburator flooding issues along with fule leaking due to flooding ( i might just get my Nikki rebuilt, it probably hasn't been serviced in 20 years)
What has no issues, engine idle, smooth
engine power after 2700 rpm fantastic
AC - less than 100 rpm drop with ice-cold AC .
I have not run the engine to 7k yet, the highest I have gone is 5800 RPM .
No other leaks, I check every day..
If you over torque the threaded fittings you can crack the boss really easily. The only fix for this is to have a proper shop weld repair the oil cooler or find a new one.
I did exactly that after putting in my new engine..
It's leaking on the other side by the welds ( right under the radiator hoses ) the mechanic who did my car never touched the hoses, he removed them engine side as instructed.
Take the cooler to a radiator repair shop. They can repair and pressure test it. To do a pressure test, you'll need to remove the internal thermostat under the big nut.
Last edited by KansasCityREPU; 09-08-20 at 11:15 AM.
Also worth considering a small-aircraft mechanic shop for this sort of aluminum repair. Private planes all use aluminum coolers and with the safety regs, these need to be repaired properly. Maybe more $$ but more thorough...esp considering how hard the FMOCs are to find replacements if some rad-shop-jockey bungles the job...
So I've hit a roadblock, I don't know how to remove the bolts that attach it to the engine. I bought a 23 mm socket and it fits but has play, the 22 doesn't fit 7/8 doesn't fit , 15/16 is too big. I dunno how hard the mechanic torqued the bolt but it's tight enough I'm going to damage the bolt unless the socket is snug.
Are you using sockets are wrenches? The connection on the front cover will take two wrenches. I forget the size but one needs to be skinny. I ground a cheap one down. I have -10An lines now so I'm not sure of the factory size.
Are you using sockets are wrenches? The connection on the front cover will take two wrenches. I forget the size but one needs to be skinny. I ground a cheap one down. I have -10An lines now so I'm not sure of the factory size.
wrenches, but the rear one can have as socket applied to it can it not?
that banjo bolt is so sketchy, , it has rounded edges even new from atkins.. yikes. Do you recommend using penetration fluid , or will that not work since it's designed to keep liquid in. ?
You only need to take the connections off at the cooler itself unless you're replacing the hoses. You can also try a six-point socket or wrench. I don't like twelve point. Penetration fluid won't do anything.
Last edited by KansasCityREPU; 09-09-20 at 03:02 PM.
You only need to take the connections off at the cooler itself unless you're replacing the hoses. You can also try a six-point socket or wrench. I don't like twelve point. Penetration fluid won't do anything.
Iv has been told to not remove the sockets from the oil cooler because I'm risking breaking the lines, but since its already busted they can fix any damage i do then too.
I give up, the bolts that attach to the cooler are not 23, probably 22, i used a crescent wrench to hold the inner bolt in place ( is that the one I'm supposed to hold, and to turn the outer one. ) i for the love of god can do not turn the outer bolt and I'm going full force. **** that oil cooler. anyways can anyone please give me the correct wrench size? I don't have money to be buying wrenches to see which fits, my local AutoZone is picky about used tools. My dad does thave anything larger than 20 mm .
The green arrow is the direction I'm turning ( counter-clockwise) .
What is the size I need for A , what is the size I need for B , Which one do I turn A/B, and which one do I hold when turning?
The inner size is 22mm and the outer is 27mm. I have a 1 1/16 wrench but it's 27mm doing the conversion. The biggest metric wrench I have is 25 and it didn't fit. it could be a 26mm but I don't have one to test. A big crescent wrench would also work but it's a tight space.
Hold the inner still and turn the outer the the left (ccw).
Last edited by KansasCityREPU; 09-09-20 at 08:24 PM.
The inner size is 22mm and the outer is 27mm. I have a 1 1/16 wrench but it's 27mm doing the conversion. The biggest metric wrench I have is 25 and it didn't fit. it could be a 26mm but I don't have one to test. A big crescent wrench would also work but it's a tight space.
Hold the inner still and turn the outer the the left (ccw).
Thank you! Sorry i need so much guidance. To think I did the entire brake system on this car by my self ( looks around nervously)
So I went out and bought a 22 and a 1 1/16 , the 1 1/16 is too big , 22 fit like a glove, I'm guessing the correct size is 22 and 26 . MY dad said he would buy some craftsman wrenches tomorrow since the crap at pep boys garbage.
Good news bad news.
Good news : i got the cooler off
Bad news: no one near me fixes them, the guy who did my radiator died and the people who took over his shop are total dumb asses ( they even claim my radiator is too old to repair.. the last guy not only pressure tested it but left it like new..)
I understand there's no aftermarket stuff.. but why? Why is it so important to have that thermostat . https://csfrace.com/csfs-new-line-of...l-oil-coolers/ makes some universal ones ( even some exact fit for FC's)
The thermostat keeps the oil in the engine until the engine reaches proper operating temp, just like the coolant thermostat. It closes once the oil cools back down to the proper temp, again just like the coolant thermostat. The rotary uses both the oil and coolant to cool the engine. Piston motors (street cars) only use the coolant. Most piston motors don't have any oil cooler, and if you choose to add one its to help keep the oil from breaking down in high temp performance applications, like racing. Its usually not for engine cooling, like the rotary.
What is the set point on the oil cooler thermostat? What temp opens it?
On my race car I have used OE coolers (2 plumbed in parallel) and we always remove the thermostat and install a dowel that forces the oil to circulate properly. Generally I see oil temps register on my oil temp gauge before I take the green flag. On a hot day, I start to see oil temps in the 150F range before I leave the false grid. Meaning that it doesn't take a long time for a rotary to get hot. We take out the thermostats because they are a potential failure point.
If it is that important, you can buy after market oil cooler thermostats and plumb them into the aftermarket cooler you decide to install on your car. A google search netted this one: https://www.summitracing.com/parts/e...SABEgLWgvD_BwE There are others out there. You would need to switch to AN -10 hoses but honestly they are better than the ancient hoses that are on your car.
As far as a repair for your existing cooler, you need to find someone that can TIG weld aluminum. They don't have to work at a radiator repair shop, just be willing to make the repair. This can be a challenging repair to make because the aluminum has been exposed to oil for a long time. So getting a clean weld may be difficult. But it apparently can be done.
What is the set point on the oil cooler thermostat? What temp opens it?
On my race car I have used OE coolers (2 plumbed in parallel) and we always remove the thermostat and install a dowel that forces the oil to circulate properly. Generally I see oil temps register on my oil temp gauge before I take the green flag. On a hot day, I start to see oil temps in the 150F range before I leave the false grid. Meaning that it doesn't take a long time for a rotary to get hot. We take out the thermostats because they are a potential failure point.
If it is that important, you can buy after market oil cooler thermostats and plumb them into the aftermarket cooler you decide to install on your car. A google search netted this one: https://www.summitracing.com/parts/e...SABEgLWgvD_BwE There are others out there. You would need to switch to AN -10 hoses but honestly they are better than the ancient hoses that are on your car.
As far as a repair for your existing cooler, you need to find someone that can TIG weld aluminum. They don't have to work at a radiator repair shop, just be willing to make the repair. This can be a challenging repair to make because the aluminum has been exposed to oil for a long time. So getting a clean weld may be difficult. But it apparently can be done.
This is a good point.
Frogman. if you decide to go the aftermarket cooler option, there are a few much cheaper then what you posted. Also, if you go aftermarket, get one that has -10AN fittings and buy/make new oil lines.
09-07-20, 03:53 PM
