90 oil cooler

[JamiesTSI]

Ok guys I did about 2 hours of reading. What I could not seem to find out are what ports would I use on my 1992 water cooled oil filter housing to plumb in a 1990 air-air cooler?

i.e. what port on the OFH would I send oil to the cooler with. And what port would I hook the return line up to?

I did find out that the 1990 oil cooler uses a 16 x 1.5 mm bolt. Any idea what the bolt sizes are the OFH uses? I'll need to call Jegs or Summit and see if they can get me a AN to metric fitting. Once I get this little project done I will post any and all part numbers I come across. Maybe someone else could use the info.

Also should I mount the cooler with the inlet/outlet up or down?

Thanks for looking and thanks for any and all help.

 

[Agent Ezzard]

I got these fittings from Jegs:

 

[BUCK]

^ Excellent ^ but you'll need an Aftermarket Low Oil Temp Oil Cooler Cutoff Valve too up North.

 

[Agent Ezzard]

I love living in sunny south Florida. Besides the fact that we've been getting gang-banged by hurricanes this year. BUCK, it seems that we always have input on these oil cooler threads.

 

[4whlbst]

I cant remeber exactly where but I think it was either slowboy racing or machv that sells the coolers, oil filter housings and fittings seperately, there they list the exact sizes of the fittings you need as well as where to plumb them. However, if memory serves I didnt know you could plumb a 90 oil cooler in to the 91 and later housing and have it be effective. I think it is because there is only one fitting after the coolant cooler on the housing and it would heat the oil coming out of the air cooler as the coolant is hotter than ambient air. Because if you plumb one side before the filter and one side after the filter than you would be bypassing the oil filter and thats not good either. Now I may be wrong but if memory serves me correctly that is the case. But check around on the vendor websites one of them lists the info you need.

 

[BUCK]

However, if memory serves I didnt know you could plumb a 90 oil cooler in to the 91 and later housing and have it be effective. I think it is because there is only one fitting after the coolant cooler on the housing and it would heat the oil coming out of the air cooler as the coolant is hotter than ambient air. Because if you plumb one side before the filter and one side after the filter than you would be bypassing the oil filter and thats not good either. Now I may be wrong but if memory serves me correctly that is the case.

That's a NEW twist - haven't seen THAT posted on this subject... there were LOTS of Ports on my 91 OFH...

 

[Suparata]

^ Excellent ^ but you'll need an Aftermarket Low Oil Temp Oil Cooler Cutoff Valve too up North - my gallery has pix of a 91 - 6-Bolt setup.

Now that’s a fancy name for a “thermostatic” oil cooler by-pass valve. I was trying to find the pictures on your website to see where did you find “lots” of ports on the oil filter housing.
Guys why don’t you make your life easier and get the housing with provisions for an external air/oil cooler? That way you do get the bypass valve that is needed no matter where you live: Florida or Alaska. You also get ports that have an adequate size for the lines needed (preferably -10AN).

 

[BUCK]

Now that’s a fancy name for a “thermostatic” oil cooler by-pass valve. ).

Different Nomenclature - same part - the beloved DSM Manual calls it a Low Oil Temp Oil Cooler Cutoff Valve...

I was trying to find the pictures on your website to see where did you find “lots” of ports on the oil filter housing.

There were 3 unused Ports available - still an unused one at the Front of OFH.

Guys why don’t you make your life easier and get the housing with provisions for an external air/oil cooler?

I was just answering his question Sup -

What I could not seem to find out are what ports would I use on my 1992 water cooled oil filter housing to plumb in a 1990 air-air cooler? i.e. what port on the OFH would I send oil to the cooler with. And what port would I hook the return line up to?

BUCK: you'll need an Aftermarket Low Oil Temp Oil Cooler Cutoff Valve too up North -

That way you do get the bypass valve that is needed no matter where you live: Florida or Alaska. .

IMO down South & especially with Synthetic Oil you don't need the “thermostatic” oil cooler by-pass valve - Up North you CERTAINLY do....

You also get ports that have an adequate size for the lines needed (preferably -10AN).

& BTW the Ports on the front of my OFH are the same size as the 90 Ports -

 

[JamiesTSI]

Thanks for the pic. Buck. My OFH looks just like yours. Did you mount your oil cooler with ports up or down? My car gets stored for the winter do I still need the low temp oil valve? If so anybody wanna un-load it?

 

[BigBADGSX]

anyone have a part number from summit or jegs for fittings for the stock 90 oil cooler, i have a 6bolt swap in my 2g and had to run the 90 setup so i just mounted it right in the front bumper. But i want to move it over to make room for my new fmic so i need to get the fittings and some lines so i can relocate it. Any suggestions???

 

[BUCK]

Thanks for the pic. Buck. My OFH looks just like yours. Did you mount your oil cooler with ports up or down? My car gets stored for the winter do I still need the low temp oil valve? If so anybody wanna un-load it?

My Oil Cooler had the Connections at the side - I thnk I put Hot Oil IN at the bottom & "Cool" Oil OUT at the Top. I swear I'm seriously wondering now whether all we lack is the Low Oil Tem Oil Cooler Cutoff Valve Assembly screwed into the Port where my Bottom Line is hooked up & then put the Hose on the unused Lower Forward Port in my pic. There are a variety of these OFH's out there - Some of the Race guys use the NT OFH with no accessory Ports.

 

[JamiesTSI]

Summit Racing part number 9919DFJERL $9.69. This is a -6 AN to 16x1.5 mm fitting. Made by Earls.

Buck,

Do you think I still need the oil temp valve if I only drive my car in the summer?

 

[Suparata]

I was just teasing you. I know you put a lot of thinking into oil cooling and I would never go after a guy that takes care of an engine.

You should have a way to get that oil up to Operating Temperature as soon as possible and also have that oil stay at that relatively stable temperature all the time (I know that is almost impossible but that is what you would be looking for). Oil is doing what it is supposed to do best at that operating temperature so, no matter where the car is driven, the sooner it will reach that temperature the better. That is why a “thermostatic” bypass valve is such a good thing and it should be used at all times and at any given ambient temperature.

Now to the bad news. I know that you were just trying to help guys but I have to tell you that your recommendations are VERY WRONG. I finally found the picture you were saying (dumb me: I was looking on your website not your gallery) and I’ve got bad news for you. What you have in that picture is a “perfect bypass”: unfortunately a bypass of your oil filter. That setup directs the unfiltered oil through the cooler and back into the gallery that should carry the filtered oil through towards the rest of the engine. If that is the way you were running the engine, where to put the Cutoff Valve Assembly is your last problem: start thinking about rebuilding you engine because you ran all this time with oil that never got filtered.

Bottom line on a ’91and up oil filter housing there are 3 plugs that looks like they may be used for an external cooler: 2 unfiltered oil and 1 after filtration. Unfortunately they cannot be used for that purpose. Buck’s setup is completely wrong and the other way you could do it is using only the 2 unfiltered ports but that would equalize the pressure on the lines to the cooler which would result in oil never circulating through the cooler.

We all learn something everyday.
Mitch.

 

[JamiesTSI]

Hi Mitch,

Thanks for the input on the oil temp. valve. I will deffinetly get one. You have any laying around?

You mentioned three ports. On my OFH I have three in the front one on the bottom and one behind the oil pressure sensor in Bucks pic.. I count five ports that are not used on my OFH. Any chance I could still do my project?

 

[Suparata]

NO! NO! NO!
You cannot use any of the ports on a ’91 and up OFH for an external oil cooler. Beware of the fact that the “port” you are talking about “behind the oil pressure sensor in Bucks pic” is not an actual port. It is where the Pressure Relief Valve for your oiling system is and if you “use” that one you are going to have NO oil delivered to the engine.
If you insist using the ’91 and up OFH, the only way to set up for an external oil cooler is to use the so called “Sandwich Adaptor” that goes between the oil filter and the OFH which has ports (2 to 4) for oil coolers and/or remote filters. A waste of money IMHO considering the fact that for the same money you can get the RIGHT HOUSING (’90 housing). Plus the fact that the sandwich adapters forces unfiltered oil through the cooler, not something you really want.
Again “You cannot use any of the ports on a ’91 and up OFH for an external oil cooler”.
And again “You cannot use any of the ports on a ’91 and up OFH for an external oil cooler”.
But then again you could use those ports if you are doing some sort of a destructive tests on your engine. It is your choice.
Mitch.

 

[4whlbst]

NO! NO! NO!
You cannot use any of the ports on a ’91 and up OFH for an external oil cooler. Beware of the fact that the “port” you are talking about “behind the oil pressure sensor in Bucks pic” is not an actual port. It is where the Pressure Relief Valve for your oiling system is and if you “use” that one you are going to have NO oil delivered to the engine.
If you insist using the ’91 and up OFH, the only way to set up for an external oil cooler is to use the so called “Sandwich Adaptor” that goes between the oil filter and the OFH which has ports (2 to 4) for oil coolers and/or remote filters. A waste of money IMHO considering the fact that for the same money you can get the RIGHT HOUSING (’90 housing). Plus the fact that the sandwich adapters forces unfiltered oil through the cooler, not something you really want.
Again “You cannot use any of the ports on a ’91 and up OFH for an external oil cooler”.
And again “You cannot use any of the ports on a ’91 and up OFH for an external oil cooler”.
But then again you could use those ports if you are doing some sort of a destructive tests on your engine. It is your choice.
Mitch.

That was pretty much waht I was trying to say, but fancier.
Just buy a 90 housing and know it is done right.

 

[JamiesTSI]

Ok everybody here is how I set my 1992 OFH up with an air based cooler from a 1990 DSM. First I removed that piece of junk water based cooler. Then I took a 16 x 1.5 mm starter tap and tapped the bottom hole on the front. I had to tap it about 3 inches back. The purpose is to block that channel off and force the oil to go throw my cooler. Next I cut new threads on the plug I removed. Right before the plug gets seated I put a little lock tight on the threads. I also went with a Auto meter oil temp gauge I put the sensor in the top port on the front. I had to take a Dremel and doctor up the inside a little to get the probe to go in far enough. I also have a Auto meter oil pressure gauge on the in-let of the OFH. I figured since I don't run my car in the winter I will be just fine without the low oil temp bypass. If any body has any questions I can try and help out.

 

[BUCK]

If Sup's right - & I think he is BTW - Isn't the one above also an Oil Filter Bypass?

 

[Tevenor]

Ugh.


Review this image:

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As you can see there are 2 relief valves. There is a pressure release valve and a temp release valve. The temp release valve lets filtered oil circulate without going through the cooler. The pressure release releases unfiltered oil back into the pan.


If you take any line of the 91 and up coolers pre filter and connect it post filter, why even install a filter at all? If you own a 6-bolt block, buy a damned 90 filter housing that already has the mounts for the external oil cooler.

 

[BUCK]

Great Thread - Thanx - I did some corrective editting to my Posts above...

 

[Suparata]

If Sup's right - & I think he is BTW - Isn't the one above also an Oil Filter Bypass?

Buck,
Sorry for your troubles and please understand that I had to say what I think so others will not do the same mistake you did. I know it hurts especially when all you tried was to make things better.

If he did it the way I think he did it will work and it is not a “filter by-pass” since both ports are before filtration (which is one of the things I don’t like).

BUT… I do have a few “problems” with that setup but I also need to work on stuff in the shop too so I will be back later.
Mitch.

 

[JamiesTSI]

For everybody that is talking smack. Please take a OFH off a DSM and compare the ports with the ones I used. Alls I did was block the oil passage off on the the stock OFH and made the oil go the way I want it to.

 

[Suparata]

There is no need to be aggressive. I admire your perseverance in “finding a way” that would work but that doesn’t mean what you did is ideal.

First let me tell you what I think you did just to be sure we are on the same page here. You tapped the lower hole in the front by the warning light sensor further back until you passed the passage that goes to the filter and then plugged that channel to force the oil to go through the cooler. Sounds good but the thread sizes you mentioned don’t jive. I believe you should have tapped the hole deeper using a 3/8 pipe thread and use a tapered plug to seal that gallery and also make sure that the plug locks itself in the hole.

Second and most of all the lines that you are using are too small. Anything less than ½” is a restriction that’s why you need to go at least -10AN (I know that the fittings on the stock cooler are only 16x1.5mm but that cooler is not necessarily the best thing you can get plus you shouldn’t use a used cooler that might have little “monsters” trapped in there waiting to devour your dear engine). The solution would be: after you did the tapping for the 3/8” plug, you should drill and tap the two OFH outlets to a bigger size. Let’s say metric 18x1.5mm or standard ½”. If you go metric you will also need to machine the mating surface flat (spot-face it) to get the correct surface for a washer to seal. On the other hand if you go to a 1/2” tapered thread you are done. This is how I would see this thing “work” but even so there are still things that I don’t like and with the price of tooling and/or machining you are already up to the price of a ’90 style OFH.

So what’s missing compared to a ’90 OFH even after all that machining? Two things: one can be fixed and one might not be considered important but I think it is.
First the “thermostatic” valve which I already said that it makes no difference where you drive your car: you should have one! A solution to that would be and external inline oil thermostat mounted like the name says on the lines that go to the cooler. That would be an additional $40 bucks or so.
Second the 90^ connectors that you would need to use to route the lines without bending the shit out of them. 90^ bends in a line are restrictions unless the size of the bend is bigger than the size of the rest of the galleries/lines within the system.

So let’s assume that everything was done correctly, the sizes are adequate and there is a thermostat in the system. What do you end up with besides the expenses? You end up with a cooler on the un-filtered side of the system which is far from ideal.

Bottom line it is not a bad idea when you don’t have another choice as far as a different OFH out there but we do have a “direct fit” one for a more than reasonable price.
Mitch.

 

[JamiesTSI]

I think if I had the wrong tap it would have pulled the threads. What can I say the tap I used worked just fine, 16 x 1.5 mm. Tap threads past the entrance to the oil filter inlet with your "starter" tap. As you thread the plug in past the entrance it will naturally get tight as it comes closer to the un-cut threads. Remember a little lock tight goes along way. Make sure to run the plug past the oil filter entrance. Be sure to use the red lock tight for this part. Are there standard thread sizes on a DSM? I thought they where all metric?

I'm not sure what lines you are looking at but the lines and banjo fitting that I got with the cooler are no where near 1/2 an inch. My -6 AN lines are bigger. And shorter in distance. Did they have a bigger oil pumper in the 1990's?

No need to run a low oil temp valve in the summer time in my opinion. Everybody knows that the oil runs hot in are cars. For everybody that might be wondering, you want to have your oil and water temps about the same. If any things you might want the oil to be a little cooler. But not much. I'll post my oil temps once I get it back on the car.

Total cost for this project less then $40.00. My friend donated the oil cooler to me. I had my own taps and dies. I had the hose and hose ends laying around. Only cost where the AN to metric adaptors.

What can I say I enjoy doing custom things to my car.

 

[Suparata]

You said what you did and I said what could have been done. But you still didn’t say what were the threads on the adaptor-to-AN that you used and of course how the sealing is done to the OFH.
The threads may not be standard sizes but they are tapered and very close to the standard pipe threads.
I am looking at your lines and I repeat: anything less than -10AN is restrictive. -6AN is .34”ID and -10AN is .56”ID so don’t be mislead by the exterior appearance of a -6AN: it is tinny on the inside (good for the power steering system and fuel lines). The fact that Mitsu chose to go with small lines and banjo fittings on top of that does not make it right, does it? We are here because we are trying to make things better for engines that are seeing a lot more “abuse” than they were intended to. The fact is that the galleries on our oiling systems are roughly ½” big and that’s why, when you “choke” them down to less than that is not good.

If I ever read that you don’t “need” a low oil temperature valve I’m going ballistic. You have the choice not to run with one but that is only your choice. I’ll say this one more time: OIL GETS PRETTY HOT BUT IT IS COLD BEFORE IT GETS THERE. It takes a lot more time to get the oil to operating temperature than to get the coolant to the operating temperature. Drive the car in short trips( city driving for example) and you will never get that oil where it should be to perform it’s “duties”. And that temperature should be slightly higher than coolant temps (around 10^C higher).

Is this thread going to become just another thread where I feel like I’ve just wasted my time because nobody listens?