newbie changine headgasket...maybe head studs?

[Xplorer99]

hey guys, iv been reading up alot on here about changing the headgasket and that most everyone has it blow again right after replacing it do to worn out head studs. well i got my 400ex tore all the way down to the motor, just gotta take the head off. i am thinking im going to get the gt thunder headbolts. i guess my main question is how do i go about removing the head? i did rebuilds on lawnmower engines in school 5 years ago and dont remember much lol. a honda repair manual is on my x-mas list too. any suggestions tips will be much appreciated! also the wheeler smokes a bit when u first start it when its cold, im thinking the rings might be bad... how do i check those?
i hope to start back on it in the morning.
o i have the 440 motor btw


thanks, Jake

[rocky_mtn_honda]

http://www.sendspace.com/file/wcy9is
merry early christmas...theres your manual
that manual should get ya goin no problem, its the factory honda one. and if its smokin at startup, id replace the valve seals before i just jumped into the rings and piston...just my .02.

[honda400ex2003]

agreed with rocky, if it smokes only on start up and if you notice it under hard acceleration it is the valve seals. The head just unbolts along with the cam. make sure you dont let the chain fall all the way down and you will be good. make sure to torque it back down properly using the correct specs in the manual and you will be good with the gt studs. steve

[jdog75]

Originally posted by rocky_mtn_honda
http://www.sendspace.com/file/wcy9is
merry early christmas...theres your manual
that manual should get ya goin no problem, its the factory honda one. and if its smokin at startup, id replace the valve seals before i just jumped into the rings and piston...just my .02.

Are you serious i paid 6 dollars for that same thing

[rocky_mtn_honda]

im sorry...you got taken. if it will make you feel any better, i have just about every manual there is, except for the 2002 and newer 400ex's...so if you need another, just let me know

[honda400ex2003]

Originally posted by jdog75
Are you serious i paid 6 dollars for that same thing

OWNED sorry bro. that really sucks to hear that you paid for one. did you get it from ebay or somewhere else? sorry not trying take over the thread. steve

[Xplorer99]

Originally posted by jdog75
Are you serious i paid 6 dollars for that same thing

dont feel bad, when i bought my grizzly last year i bought a yamaha manual for it... it was like 60 bucks lol


o ya i did read about the valve seals. ill look into doing that also. how do u put the gt t studs in? would a honda dealer do that u think? thanks for the manual i appreciate it! :D

[rocky_mtn_honda]

np...and you'd probably want to send your jug off to gt thunder, or have a machine shop install them for you...im pretty sure you cant do it yourself.

EDIT: http://www.exriders.com/vbb/showthread.php?s=&threadid=412708&highlight=roll+formed or http://www.exriders.com/vbb/showthread.php?s=&threadid=241606&highlight=roll+formed

[Xplorer99]

Originally posted by rocky_mtn_honda
np...and you'd probably want to send your jug off to gt thunder, or have a machine shop install them for you...im pretty sure you cant do it yourself.

EDIT: http://www.exriders.com/vbb/showthread.php?s=&threadid=412708&highlight=roll+formed or http://www.exriders.com/vbb/showthread.php?s=&threadid=241606&highlight=roll+formed

ya i know i cant do it myself, i was wondering if dealers would be able to do it, ill have to make some phone calls to see if anyone around here can do it. probably be easier to send it to gtt im guessing. looks like its pretty much tearing the motor all apart to do that tho.... can someone explain this to me a little better? how to u turn the crankshaft?

Rotate the crankshaft counterclockwise and align the
"T" mark on the flywheel with the index notch in the
left crankcase cover so that the cam lobes are facing down.

[Xplorer99]

am i going to need any special tools to go as far as taking the jug off? guess ill replace the rings if they are bad since they gotta come out anyway.

[rocky_mtn_honda]

well theres an access hole on the left side of the case that has a 10mm allen, take that out and get a 17mm socket setup on your ratchet. then take the other 6mm allen out and thats where you can see the "T" mark on the flywheel when you have the crank turned to the right position...you sure you should be workin on these things? lol j/k make sure you only turn counterclockwise on the crank though, if you pass the "T", keep turnin counterclockwise until you come back around to it.
as far as taking the head and jug off, just remove the valve cover through bolt, think its a 14mm, then take all the 8mm's out of the valve cover, dont forget the 12mm center valve cover bolt...take your valve cover off, now its time to take the cam out...6mm allen will remove the cam gear, then make sure and tie your chain up so it doesnt fall in the bottom end, also keep an eye on that plunger and spring for the decompressor mech. pull it out so you dont lose it or it falls into the motor, just make sure to put it back in, cause youll play hell getting it started if its missing...then remove the 4 head retaining nuts...i think they are 14mm as well, then the 4 jug retaining bolts come out, voila
hope i didnt miss anything
take note of the way the cam bearings are facing, the sealed bearing must be placed back facing the same direction for proper lubrication to the journals
any other questions dont hesitate to ask :p

[Xplorer99]

ok ill give it a shot this weekend i hope. just wanted to be sure how to turn the crank, you put the socket into the motor then. iv never done this by myself. i had a teacher showing me what to do back in highschool and i havent had a small engine apart since then so it should be fun. thanks for all the help. anything goes wrong youll be hearing from me lol

[honda400ex2003]

just take it slow, and mark everything you take off in a bin or something to make sure you know where it goes and what it goes with. it isnt too bad if you do this. take pictures also they help to get it back together faster too since you can see where everything went. steve

[jasonwayne222]

when u get the jug and head back on, before u start turning the crank to line up th T mark you want to hold the timing chain with one hand to make sure it doesnt get binded up when it starts turning, and if it falls down just get a long magnet and it will come right out no problem. If your lucky none of your valve cover bolts will break, almost everyone i know including myself who has a 400ex has had at least one or a couple of these bolts break, just get a helicoil kit and repair them.

[Xplorer99]

well i did it lol. didnt take long, nothing went wrong, no broken bolts!!!! the motor was bored to 440 a year and half ago, the bolts still had ALOT of neverseaze on them lol. any tips on cleaning the piston head? and the other stuff? thanks again guys!

[rocky_mtn_honda]

glad to hear you got it torn down ok. parts cleaner solvent is best to use, but u can use whatever you want really. something with good degreasing properties really speeds things up. honestly, i know its old school, and probably bad for you, but i like gasoline. unless you have a parts washer at your disposal. if you use gas, at least wear latex gloves or something it really dries the skin out lol

[honda400ex2003]

also wear gloves with carb cleaner or brake parts cleaner if you use it. that is really bad especially if you have a ring or something on and it gets underneath. it will stay irritated for a couple of days. steve

[Xplorer99]

Originally posted by rocky_mtn_honda
http://www.sendspace.com/file/wcy9is
merry early christmas...theres your manual
that manual should get ya goin no problem, its the factory honda one. and if its smokin at startup, id replace the valve seals before i just jumped into the rings and piston...just my .02.

do you happen to have the manual for a 05 450R ?

[rocky_mtn_honda]

pm me

[Xplorer99]

well im looking at gaskets....the top two look identical but have different part numbers. and would i need head gasket made for the 440? thanks

http://www.denniskirk.com/jsp/tpl/cmn/prodlist.jsp;jsessionid=Y0OHOW0NIQ1BVLA0WTKSM4VMDK 0NCIV0?store=Main&category=11006&np=&mmyId=6106

[honda400ex2003]

if you havent done your valve seals you could get the second 73.99 cometic one for the 89 mm which has them in it already or if you did then get a different 89mm set. the first cometic one is for an 86 mm bore. it is not critical to have the correct size but with a 440 you want to have it fit the best you can since it could blow easier with a different gasket in it. I got a full set since i was going to be doing a cam chain and such with mine. steve

[Xplorer99]

well i do want to replace the vavle seals since thats what i was told is making it smoke on cold startup...

[honda400ex2003]

that would be my guess as to the smoking. if you dont want a full kit get the second kit of the cometic ones for 73 in my opinion. i have had good luck with mine along with many others on here. it is up to you though. steve

[416ex xc racing]

i would get head studs from gt thunder they got some good one but it will cost u about $150 to get them stuck in u shouldn't be able to pull them out

[Xplorer99]

Originally posted by 416ex xc racing
i would get head studs from gt thunder they got some good one but it will cost u about $150 to get them stuck in u shouldn't be able to pull them out

that is my plan, just waiting on the next paycheck to get it done

[Xplorer99]

any suggestions for cleaning the piston and head, pretty nasty lol, dont wanna use something and scratch it etc

[Xplorer99]

:huh i measured the cylinder with a caliper and its exactly 3.4 inches.....witch is 86.36 mm ??? :eek2:

[rocky_mtn_honda]

then i'd have to say its not the 89mm big bore you though it was...what does the piston measure? im pretty sure your only supposed to have around .002 clearance...doesnt sound good

[Xplorer99]

Originally posted by rocky_mtn_honda
then i'd have to say its not the 89mm big bore you though it was...what does the piston measure? im pretty sure your only supposed to have around .002 clearance...doesnt sound good

i was told that it had the 440 big bore kit with all the mods i listed in my sig.... i wouldnt have bought it if it wasnt lol. i didnt check piston ill go do that now. how do i check the cam and jets in it? maybe since i have it all torn apart ill make it a 440 since thats what i wanted in the first place lol

[rocky_mtn_honda]

pull the screws out of the bottom of the carb bowl and pull the jets with a small flathead screwdriver, they should be stamped with numbers if they are keihin. as far as the cam goes, post a pic up and im sure someone can identify it...not my area of expertise. might have to take some measurements on the lobes.

[Xplorer99]

the side of the carb says keihin. but i know its jetted somehow cuz there are 2 big holes in the airbox lid. i taped them off with duct tape and it would onll idle, give it any throttle and it died lol. it was fine after uncovering the holes. ill take some pics of the cam. im thinking i might make it a 440 if its not too costly since its apart now anyway and cant ride it for another 3 months

[dubee]

Hey ROCKY do you got the manual to a 96 300ex?? and a xr650l??

[Xplorer99]

i was qouted this from GTThunder

Sleeve, install sleeve, 440 wiseco piston, head studs, install headstuds, gaskets - $639.90.


BUT i talk to my friend today about race fuel....60 bucks for 5 gallons....

[honda400ex2003]

if you stick with 11:1 you should be able to get away with a mix or even 93 if you can find it around. steve

[F-16Guy]

Originally posted by Xplorer99
i was told that it had the 440 big bore kit with all the mods i listed in my sig.... i wouldnt have bought it if it wasnt lol. i didnt check piston ill go do that now. how do i check the cam and jets in it? maybe since i have it all torn apart ill make it a 440 since thats what i wanted in the first place lol
Maybe you have a 440 stroker!!?? Probably not, but that would be sweet.

[rocky_mtn_honda]

dubee, pm me for manual requests

[Xplorer99]

ok i was starting to think twice b/c i seen that most 440 kits where 12:1 or higher compression. i would like to get 11:1 compression and be able to run 93 octane pump gas, or maybe a little higher mix. its nothing for me to ride 60-75 miles or more at a time, some times a couple times a week. so i dont wanna be spending 30 bucks or more everyday i ride. i have no problem buying the 93, just dont wanna have to run a really high octane.

but anyway i think im going to bore it out to 440. so i found this kit, would it work?

id rather buy stuff little by little rather than pay GTT a big lump sum, id rather just have them bore it out and put in the studs.

http://www.denniskirk.com/jsp/product_catalog/Product.jsp%3bjsessionid=YTTTFGVR5UTL5LA0WTKSM4VMD K0NCIV0?skuId=4667M08900&catId=110&leafCatId=11007

[honda400ex2003]

along with the piston selection above you would need a sleeve from LA sleeve
http://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=149205&store=&catId=&productId=p149205&leafCatId=&mmyId=2354

and the piston
http://www.denniskirk.com/jsp/produ...leafCatId=11007

along with a top end gasket kit at the very least with is about another 50 to 075 depending on if yoiu get one with valve seals or not.
http://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=262778&store=&catId=&productId=p261351&leafCatId=&mmyId=2354

or this onehttp://www.denniskirk.com/jsp/product_catalog/Product.jsp?skuId=263566&store=&catId=&productId=p263566&leafCatId=&mmyId=2354

notice they are for a 89mm bore. then you have to take into consideration the price to get the old sleeve pressed out, and the new one in. the cylinder has to be machined to accept the new sleeve.
also you will would want to get the hd studs so that is another 150.

this thing adds up fast doesnt it.

Steve

[Xplorer99]

Originally posted by honda400ex2003


this thing adds up fast doesnt it.

Steve

yes it does lol. but thanks for the parts list. ill get it done little by little over the winter and hopefully be done by spring, if not, i should have a good income tax return to help finish it up lol

[honda400ex2003]

there ya go, i would suggest doing the valve seals too if you have an older machine with some time on it. They get wore out and start to make it burn oil on startup and under hard acceleration. just an option for you though if you send the cylinder to gt they may also be able to do the valve seals. any shop should be able to do that though. steve

[Xplorer99]

yes it does need the valve seals replaced, smokes kinda bad when u start it up cold untill its warms. ya i am hoping to have GTT do all the machine work to the motor and valve seals, then ill put it back together.

[Xplorer99]

are there any other things ill have to change when i go to 440? different jets or anything?

[honda400ex2003]

yeah you will want to rejet for sure. what other mods will you have already to add to the kit, an exhaust, filter, anything else? We can help to get in the ball park on jetting so you arent buying 10 jets and such. your sig shows that you have a 440 already whats up with that? lol Steve

[Xplorer99]

well im told it has a stage 2 hotcam. it has "White bros headers into a custom carbonfiber micron can" i know its a micron exhaust. has a Uni airfillter, im repacing it with a new one and getting an Outerwears for it. it does have 2 1-1/2" holes cut in the air box lid for more air flow. im not sure what jets are in it right now but i will look here sometime

[honda400ex2003]

you will probably be into the 175 keihin at the minimum. i would say closer to a 180. you should do a bit of reading in the sticky at the top, there are quite a few different setups at different elevations to help you out. i would start with around a 185 if you have one. note this is not the same as your dyno jets you have now, they are smaller, there is also a table in the 400ex tuning thread that is helpful. if you search for 400ex chart, you will find the one i am talking about. the equivalent to that is around a 165 or so if am not mistaken. check it out and see what some of the other guys are running with the 440s. steve

[honda400ex2003]

heres the thread with the conversion in it
http://www.exriders.com/vbb/showthread.php?s=&threadid=344906&highlight=400ex+chart

you can also check out some of the sigs and such in the thread to see if there is any jetting stuff in them. steve

[F-16Guy]

If money is a concern, why not do an 11:1 426 instead of the 440 (which is really only a 434cc anyway)? You'd save the money involved with the sleeve change, and the piston will be a few bucks cheaper, too. Hell, you could even do a 12.5:1 426 and run E85, you just have to jet accordingly. It seems to me that the sleeve work is usually the weak link in most 440 builds, so have someone who knows what they're doing install it.

[Xplorer99]

im not too concerned about money, like i said i have all winter to do it. whats the average cost of a sleeve change? im thinking ill have GT Thunder do it.

[F-16Guy]

The machine work for the resleeve/bore/finish hone is generally around $125. That price for the piston kit looks way high to me. Check out Lukes Racing (scroll down to the bottom row of photos for the XR/TRX 400 big bore kit). They only want $175 for the piston, sleeve, and gaskets.

http://www.lukesracing.com/

If you want a true 11:1 ratio with the 89mm Wiseco flat top piston, you'll probably have to deck the cylinder. Read this:

http://www.exriders.com/vbb/showthread.php?s=&threadid=8316&highlight=decked

[Xplorer99]

well i went to Lukes Racing and it said " Attention: We are not accepting any new service work at this time. Nikasil plating, porting, crankshaft service, engine service will be unavailable until summer time. "

they are like 45 mins away from me too....

[F-16Guy]

You can get the parts, though, and save a big chunk of money over Dennis Kirk and probably GTT. My strategy has always been save money on parts and pay to have good machine work done. Parts are parts, and getting the same parts cheaper doesn't make the parts any worse. With machine work, however, you often get what you pay for, and poor machine work can ruin a build.

[honda400ex2003]

If i was going to do it again and had all winter i would wait on ebay and see what you can find. you can get some good deals on parts on there, and sometimes you can get cylinders with the piston for the price of a piston itself. wait for the piston and the gaskets you want to come at the right price and boom, you already have the rest so it should be pretty easy for you. no cam or anything to mess with buying. also i suggest you get a hd cam chain while you are in there, but then you may want to get a full kit to have the side cover gaskets and stuff too. just another idea for you. steve

[Xplorer99]

this is developing into an addiction.....

lol


alot of great ideas guys thanks alot for all the help. i found this on ebay..
http://cgi.ebay.com/ebaymotors/Honda-400EX-11-1-440-Big-Bore-kit_W0QQcmdZViewItemQQhashZitem439c42c28eQQitemZ29 0384429710QQptZMotorsQ5fATVQ5fPartsQ5fAccessories