Micky Dunlaps oil cooler 400ex

Never heard of it until I just searched it. Have any pics of it mounted? How long have you had it? How hard of an install? What other mods do you have? Welcome to the forum btw.

I tried to upload photos the other night and it wouldn't let me .I rode with it all summer long and it seems like its making a huge dif. you have to drill and tap the clutch cover and the valve cover,but it went really smooth.there also is a ballbearing inside the clutch cover that you jb weld into the oil passage to reroute the oil flow ,quite a well thought out design. not sure how to list my mods on the website yet. but I have +2 alba a-arms,phoenix slip on pipe with velocity intake,elka stage 1 long travel zero preload,175 main,40 pilot,needle 5th notch,on stock carb.razr 21-7-10and razr 20-11-9 on stock rims. ground out the inside of the header welds,renthal bars streamline twist throttle and brake lines,omf air scoops,tusk block off plate,progrip rally gel grips,factory effex gripper seat cover,I run 93 ethanol free gas.so far so good. ill try to get pics of the oil cooler for ya.

So do you have any pictures on how to install this?? I have a cooler that I want to use but need to know where to drille and tap the covers and what not.....

i can't get link to work, but if you google "400ex oil cooler nuckinfuts" it should take you to trx450r.org with his install pics.

no tapping cases required

So they just put another cooler in line with the old one? Every time I try to go to that site my web browser locks up. I have seen that mod before, do you think it is as effective?

yes it is as effective, its the cleanest, best way to add an extra cooler.
i just lead you to his install thread because it had detailed info and pics.

you really should work at getting that site to work for you.
there is alot of great threads over there, a bit more bickering then here since they don't have moderaters anymore.

So, I just got a fresh bore on my 400ex, have not yet put it back together yet. Stepped up to a 11:1 compression piston, stage 2 cam, and putting in new jets. Do you think that just doing the extra cooler will be enough cooling? With those mods do you think it will be necessary to run hard faced rockers?

i have built many high comp(12.5+) 400s and have never needed aftermarket rockers.

my ex for the woman is 87mm 11:1, stg2 cam, hmf exhaust, fcr carb with stock rockers. and no added oil cooler! runs at good temp

you won't/shouldn't need a second cooler with your mods

Thanks for the heads up on the rockers. Seen some people on other forums that were saying that is a must, but I have never heard of such a thing.

As for the other cooler I will probably still put a second cooler on just for the fact that I am a bigger guy and don't want to have to worry about heat issues. This quad when it is done will probably be doing more long trails and such than dunes and wide open spaces so I would rather just put a little extra effort into it now than have issues later.

Hopefully I get most of my motor back together tonight! I am pretty excited to hear this bad boy run.

Well I did this yesterday, drilled and tapped and put in the plug hooked up the new cooler, and put it all back together. I have a big problem. It is POURING oil out the side of the head where I put in the fitting on the upper head. It is coming from between the upper head/valve cover and the lower head. I am wondering if the plug didn't seal in the upper head and so it is maybe double pumping oil in to the head....

Any suggestions??

figured it out!!!!!!!!! ............. I feel like an idiot........... nuff said........

Well? So I don't make the same mistake, "What did you do"?

Be sure to double check that you tightened ALL the head bolts......

Got cha's!

marioweldinginc said:

I have the FST oil cooler and stand by it 100%. If you look at my gallery you can see the radiator mounted behind the bumper. I never go past 250* no matter how hard I ride or how hot it is. I run Rotella T 15-40. I have a 500cc bbk installed also from FST. Installed is a stage 3 hotcam and I did not need hardened rockers. That being said Mickey Dunlap is a douche but his products are well made.

Click to expand...

Where can I get a FST cooler?
I am running 10-40 Amsoil
Stock engine

Thanks for the site address and mounting tip!

Another advantage is it's availability. Like you mentioned, Wal-Mart sells it. As does just about any Truck Stop and Shell station. Are you running Dino or, Syn.?

I contacted Dunlap. Looks like for around $160.00 I can have the Aux. cooler kit and, the engine cover and clutch cover machined. Thats with Dunlap charging $20.00 to do the machine work. With a 10 day turn-around. How hard is Dunlap's kit to install?

To upload pic's you need a Hosting site.

craigman45 said:

I tried to upload photos the other night and it wouldn't let me. QUOTE]

To upload pic's you need a Hosting site. Like 'Photobucket'. it's FREE.

Click to expand...

when you add onother cooler inline its not the same thing as rerouting the oil to the cam like the mickey dunlaps oil cooler