More Oil Cooling

[MIKE400EX]

About 6 mos. ago I picked up one of the PermaCool oil/gas coolers for a friends Ducatti club bike. Looked good so I picked up one for the EX too. Finally got around to installing it (for cam oil cooling) on mine and did a little testing, here's what I found.
On a 85 degree, very humid day, after some idling, 20+ minutes of trail riding and 3-4 drag runs:
Head temp. was about 240 degrees (on the sides away from exh. flanges).
Oil temp from the stock cooler into the engine was about 210 deg.
Oil temp from the cam cooler into the motor was about 190 deg.
With the OEM cam oil path running up the side of the cyl. you can safely assume that the min. oil temp to the cam would have been at least 210 deg. and probably much closer to the 240 mark (that's w/o the cooler). Now that 190 deg. figure seems much more inhabitable, and worth the minimal investment!

Something that I did find, that has not been brought up here yet:
Honda places restrictors in the oil passageways to control oil flow to different areas of the motor. Nothing new, actually they're a common necessity in almost every oiling system with a pump so that you assure a balanced & uninterrupted supply to all intended areas. With that said, if you were to block off the stock cam passageway, re-route the oil through a cooler and then dump it unrestricted into the cam "pocket" - you would certainly get more oil flow to the cam BUT you would lose (re:dump) system pressure. In doing that, much less oil, if any, will get forced into the transmission/clutch and crank bearing areas (not a good thing). A simple restrictor, such as a set screw with a hole thru it, placed in one of the fittings (as close to the head as possible) would solve this potentially disastrous situation. Honda uses a restrictor that is approx. .078" dia. in the passage to the cam. A restrictor, near the head, that is approx. .095" dia. ought to work well and allow a little more oil flow than stock, while keeping the trans/clutch & crank bearings happy.

I've never seen one of the kits from Mickey or any of the other knowledgable engine builders, but I'm sure they take that into account. I just don't want to see a bunch of people slap on an aux. oil cooler and have other parts in their engine fail.
Hope this helps some!

I'll keep you guys and gals posted as to how it works on my EX.

And FWIW, my 400EX key fits in my sons Blaster and works fine!!!?:huh

[powerslider]

Good info Mike, have you ever checked the actual oil pressure at various rpms? I'm curious as to what is at idle vs higher rpm.

[Big - D Racing]

I have been running the secondary cooler also, and ve always thought of runnng that same test, u just did it for me, thank you. Mickey Dunlap claims up to 50 degrees cooler at the head, well I guess he was telling the truth.

[MIKE400EX]

Powerslider,
Good question! I'll hook up an oil gage to the aux. cooler line (AN fittings) and see what it is. Won't be able to get to it 'til next week though.

[powerslider]

No problem Mike, I appreciate the effort/info....

[Baley69]

Where did you buy the cooler, do you have a link?

[MIKE400EX]

Baley,
Bought them from Jegs. Most auto parts stores can special order them also. I used the ones with the AN fittings (-6), not the kits. There was another thread on here recently that had the link.

[TORO1968]

Good info!! This stuff really clears up some questions I had.

Has anyone considered the increase in pressure drop across the oil cooler that most likely occurs when the stock one is swapped out for an aftermarket unit? This might not be much of a concern, however, I was wondering if it could alter the operation of the lubrication system, i.e. oil pressure, volume flow rate, etc.

Hey Mike, I was thinking that measuring the inlet and outlet oil temperatures on the stock and aftermarket coolers would also provide a good reference as to how much better the aftermarket unit works than the stock one.

How'd you obtain your oil temp and cylinder head temp readings? Just curious, because I'd like to do a little research on this topic myself. I think the easiest way to get these readings would be to mount some thermocouples on the head and oil cooler inlet/outlet then hook them up to a temperature meter or DMM. An infrared thermometer might work okay too, but based on my experience, you can't focus on one small area or line all that easily.

Have any of you guys managed to successfully mount an oil pressure gage on your 400?

-Jordan

[L.Vegas400]

when you mount an aftermarket cooler its plumbed from the filter to cooler then directly into the head to the cam. when the stock one is on, it goes from cooler back into the hot engine through the filter, up the passage way through the hot cylinder, through part of the head then into the cam.... thus raising the temp of the oil before it even gets to the head.:ermm:

[TORO1968]

More info I didn't know...thanks!!

[powerslider]

Toro, as long as you keep restrictors (as Mike mentioned) in the system in their proper locations the system pressure will be maintained regardless of the extra cooler added. That is there function, to maintain system pressure and deliver the proper volume of oil to the given locations...

[MIKE400EX]

D***, just typed a book answering all your questions and then lost the cable connection!

Toro, you could shim or replace the bypass spring to gain a little more pressure, but at the risk of heating up the oil even more or aerating it if it bypasses too much. The oil system should be designed to only bypass when the oil is cold (very viscous) or at elevated RPM's. The rest of the time it should just be able to supply enough oil to keeps things "in motion".

I plumbed the PermaCool as an aux. cooler so I can't readily tell if it's more effective. Generally the stock type coolers are more effective/efficient than the finned round tube types (ie. PermaCool). I'm sure that a second stock cooler mounted to cool the cam oil would be better, more expensive and harder to plumb. I was just looking for something that is effective, easy to install, and of course reliable. As i get older, easier is sometimes better and pushing it back through the woods is not an option.

I tried a Fluke digital temp. gage with a short, quick response thermocouple but I got very similar (good enough) results using a much handier quality infrared gun. I was able to get close enough to eliminate most of the error due to spread. I "shot" the fittings on the bike and coolers to get data. The fittings are either thin steel or aluminum so I'm sure their temp. is relatively close to the engine blood flowing through them. I was looking for temperature differences so the findings should be relative and pretty accurate.

I'll plumb a pressure gage into the aux. cooler line before the restrictor and see what it is at different RPM's. Can't do that for a few days though because I'll be away.

Powerslider, the cam galley restrictor orfice is about .078" dia. and the two that feed the clutch and trans are both about .040" dia. I havn't split the cases yet (nor do I really want to) so I don't know what the size of the one leading to the crank bearings is.

One of the duners here mentioned that he had heard of a few 400's eating the tranny's. I'm wondering if they also had an unrestricted cam cooler plumbed in there?

Be back in a few days!

Good Riding!

[bighig]

Hey MIKE400EX,

[bighig]

OOppps, I'm gonna install the FST oil cooler and read the post. Where can I get the "restricters" at, and how big, and where exactly do they go in at. Thanks for sharing that info.

[ridered448]

so youre sayin that adding a perma cooler, would actually decrease the cooling efficency, compard to the stock cooler?

[bighig]

JUST TRYING TO KEEP THE POST ROLLING

[MIKE400EX]

I havn't forgotten, I'll check the oil pressure as soon as I get it back together. :mad:

[northeast400]

does anyone make a bigger stock location cooler, and does a bigger oil tank make a difference?

[dariusld]

An oil cooler is not a terrible idea, but the oil is not where the heat problem is on the 400EX. The 400EX desperately wants to be water cooled, but that is a costly modification. The solution is to cool the motor with race fuel. High octane race gas actually helps a motor run cooler. Curtis Sparks. This quote is out of context, but you get the idea.
Here is where the qoute came from. (http://********.com/ask-the-pros/curtis-sparks/ask-curtis-sparks-4.htm)

[ATVer14]

Not that this affects any of these tests or anything, but I just wanted to get this information out there because it is a common misconseption. You mentioned that you ran the test on a very humid day, which sounds like it would make the engine run even hotter than if it were on a dry day, but, in fact, it makes it run cooler because it is an air cooled engine. Humidity is just water vapor in the air, and water can conduct heat much more efficiently than air can. Therefore, more water in the air (humidity) means more water vapor hitting the cooling fins and taking heat away from the engine, resulting in a cooler running engine. It sounds backwards, but it is the truth. MIKE400EX- you might have already know this, but I just wanted to let everyone else know. :)

[Waynes400ex]

What do you guys think about this cooler? I like it cause you can put it in place of the stock one.
http://www.deserttoyzatvracing.com/pages/786129/index.htm

[ATVer14]

It looks nice, but for $350, I think I would just try my luck with the PermaCool setup.

[Waynes400ex]

True 350 is way to much but i dont like the idea of drilling into the head cover

[RED121572]

Excellant info! My EX runs at 220 with just the oversized oil tank.

[Waynes400ex]

What % is hot fot the 400ex , by the way what tank do you have?

[cals400ex]

Originally posted by Waynes400ex
What do you guys think about this cooler? I like it cause you can put it in place of the stock one.
http://www.deserttoyzatvracing.com/pages/786129/index.htm

does anyone make another cooler that you don't have to drill into the head? i really don't like the idea of drilling either.

[Waynes400ex]

THe one i sent a link to is the only one I have seen!!

[bmw500hp]

flow to head, .84 qpm.

[F-16Guy]

ttt. I'd like to know what the results are for cooling and pressure with and without a restrictor. If there is a noticeable difference, you could probably have an inline fitting with the correct size orafice made and just plumb it into the oil hose on the perma-cool kit. One cut and two clamps and you're back to factory specs. Input?

[MIKE400EX]

BMW500HP
Could you share some specifics and test conditions/parameters? Thanks!

[Glamis400ex]

Hey Mike,

We didn't put a restrictor in mine....should I be worried??:confused:

Glamis

[L.Vegas400]

if you used the 1/8" fitting, its pretty close to the same size as the origional passage. only so much oil can flow throught the passage between the oil filter and the new line.

[MIKE400EX]

No, there is apparently enough restriction in the fittings, cooler, ~5 feet of line, and cooler oil to eliminate the need for a restrictor.

there r like 40 different kinds of oil coolers...the main brands are FST, permacool, and coolstroke...another one would be kesta or something like that...its an airplane oil cooler downsized for a 4 wheeler or dirtbike...the fst has fins on the inside to make the oil touch the walls...the perma doesnt....the coolstroke is a plate cooler as is the kesta...the cheapest is perma...second is coolstroke...fst...then kesta or whatever...the airplane cooler is $350 so...thats a lil high...i made a thread about this a while back...i think it got up to around 250 replies or so....5000 veiws...or something like that....but it got closed because me and 3 other people were arguing with mickey dunlap...and some dude started fighting like cursing ect...so it got closed....but if u can find it it has A TON of good info for you guys...check it out some time

[JD400exrider]

I too do not like the idea of drilling into the head. Anyone running the oversized cooler that bolts right up. 350.00 OUCH :eek2:

[Max400]

tapping the holes into the head was not as big of a deal as I thought!!! It was really simple........

[F-16Guy]

Originally posted by Max400
tapping the holes into the head was not as big of a deal as I thought!!! It was really simple........
The rocker cover was a no-brainer, but the clutch cover was a little more involved. When I did my buddy's bike, I drilled carefully and then tapped using a good cutting oil. As the tap bottomed out, I ground it down a little at a time until the fitting could be tightened to the correct depth. Might take a little longer that way, but I got very good results, and no plugs where you have to drill through to allow the tap to clear. Mike400ex, I tend to agree-- there should be enough added restriction without adding a restrictor.

[Chanman420q]

Originally posted by MIKE400EX


And FWIW, my 400EX key fits in my sons Blaster and works fine!!!?:huh

yea it works that way with my friends blaster too....... but not the other way around

[MIKE400EX]

F-16 Guy,
We'll see, I just replaced the cam and rockers, and took out the restrictor.

Chanman, same here - Blaster key doesn't work in the 400.
My 70 240Z (Scarab) key was the same as our old 86 Maxima. 73 Vette key was the same as an 88 Cavalier from our shop. My Lola key is the same as my old 68 Camaro. Wife's Lincoln is the same as our neighbor's Linc. New house is (now was) the same as my work key. Seems like nothing is sacred.

[bmw500hp]

Originally posted by JD400exrider
I too do not like the idea of drilling into the head. Anyone running the oversized cooler that bolts right up. 350.00 OUCH :eek2:

John, who is selling the solid gold oil cooler? 350.00...:eek:

Heard there are 2 of these floating around now...

[JD400exrider]

Hey Mike

How did the trip go. You much be fishing you dog. :p

The link for the 350.00 cooler is in this thread on the second page. The cooler looks nice but 350.00 is a little much. There has to be another one out there for a little cheeper of the same type or brand. I would like to get a larger one that will bolt right up.

[Glamis400ex]

Drilling and tapping the head and case ain't bad at all....that is, if someone does it for free...:D

I know this will make a huge improvement on the cooling.

Glamis

[JForestZ34]

Has anyone ever thought about adding a small 12v DC fan to there oil cooler for better cooling of the oil. I'm thinking about it but just can't find a fan small enough to be able to put it in front of the oil cooler.


James

[hook]

radio shack has small fans thats 12 volt but they dont like water:(

[F-16Guy]

Originally posted by hook
radio shack has small fans thats 12 volt but they dont like water:(
.....I think I have some Scotch Guard somewhere, hmmm......lol

[L.Vegas400]

there have been a couple threads about installing a small fan. if i remember correctly, almost all of them had no problems with water, mud, or snow. i really think it would only help when your setting idleing, but if your doing that why not just kill it. if you want one,,, get'er done.

[Waynes400ex]

Did anyone else find stock replacement oversized oil cooler that was cheaper than the one for 350 that I listed>?
http://www.deserttoyzatvracing.com/pages/786129/index.htm