The Engine Rebuild!

[Brauap]

The reason I made this thread is to ask all of my questions here, and try to keep all the info organized.

Alright, so tonight I started tearing down the engine (its pretty easy) with the assistance of my Clymer's!

Before I left the garage for the night, I was trying to get the cam chain off, but I can't figure out how to get that off! I got both the bolts off the sprocket...

It's telling me to take the chain off the sprocket but it is still pretty tight on there..? Help please?

[ti2ibal1]

Originally posted by Brauap
The reason I made this thread is to ask all of my questions here, and try to keep all the info organized.

Alright, so tonight I started tearing down the engine (its pretty easy) with the assistance of my Clymer's!

Before I left the garage for the night, I was trying to get the cam chain off, but I can't figure out how to get that off! I got both the bolts off the sprocket...

It's telling me to take the chain off the sprocket but it is still pretty tight on there..? Help please?

You seriously started another new thread? :huh

[Brauap]

Originally posted by ti2ibal1
You seriously started another new thread? :huh

Yea, to make it just about the rebuild.. the other was about weither or not should I do it, this is just to make everything nice and (more) organized. I sure hope, HOPE it is alright with you that I did so! :rolleyes:

[sc400ex_rider]

have you removed the tensioner?

[bry14661]

ill bet your fourwheeler never moves again under its own power unless you drop off the million pieces at a shop

[BlasterEaten250]

Originally posted by sc400ex_rider
have you removed the tensioner? Yeah do that. And when you get the sprocket off have a bungee chord handy to hang the chain so it doesnt fall down.

[ti2ibal1]

Originally posted by bry14661
ill bet your fourwheeler never moves again under its own power unless you drop off the million pieces at a shop

I see I'm not alone.

[BlasterEaten250]

Originally posted by ti2ibal1
I see I'm not alone. You need to grow up.

[Brauap]

Originally posted by sc400ex_rider
have you removed the tensioner?

I followed the directions, and I removed the cover on the back of the engine, but then it said to stuff the passage way with a cloth so no bolts would fall down, then it said to take off the bolts on the sproket, and take off the chain.. but never said anything about the tensioner, also, should the spark plug be in or out now?

How to I take the tensioner out? It did say to put a peice of wire threw the chain to prevent it from falling and then I twisted the wire threw a bolt hole, so its not going anywhere, but thanks!


Oh and btw, bry14661 & ti2ibal1, f off.

[hoogiesngrinder]

Alright, lets try and guide you through this...

Pull the valve cover.
Pull the tensioner out.
Remove the two allen head bolts that hold the cam sprocket. You will to rotate the crank to accomplish this.
Remove cam sprocket, cam as well, don't let the chain fall down
Remove 4 head nuts, remove head...again don't let chain fall down
Remove front (exhaust side) chain slide.
Remove 4 cylinder bolts, slide off the jug...and again don't let the chain fall
Once I think about it, didn't I recommend putting a new timing chain in?? If so, let the darn thing fall. You can replace it when you pull the clutch cover off.

[440challenger]

why are all you guys scared of letting the t chain fall down. let it fall ,he has to take the cylinder off anyway. you should really put a new t chain and tensioner in it.One of the common probs with a 400 is t chain stretch

[Brauap]

"Pull the valve cover.
Pull the tensioner out.
Remove the two allen head bolts that hold the cam sprocket. You will to rotate the crank to accomplish this.
Remove cam sprocket, cam as well, don't let the chain fall down
Remove 4 head nuts, remove head...again don't let chain fall down
Remove front (exhaust side) chain slide.
Remove 4 cylinder bolts, slide off the jug...and again don't let the chain fall
Once I think about it, didn't I recommend putting a new timing chain in?? If so, let the darn thing fall. You can replace it when you pull the clutch cover off."

I got down to your take the bolts out, but the cam is in there, and won't lift, therefore I can't get the chain off the sprocket or the sprocket off the cam.. :confused: I will prolly replace the chain, it will prolly cost what, 10-20 bucks?

[storms400ex]

not trying to be a *** hole but i think you better just take the engine out and let some that knows whats going on do it but thats my 2cents

[sc400ex_rider]

the cam sprocket will slip off the cam when you take out the tensioner and remove the two allen bolts. just pull it to you, there should be some play in the chain

[Exrider434]

be careful when you take out the cam not to let the decompression spring fall down into the cases!

[Brauap]

Well, I got it in peices today! My hold up was that I didn't know that the cam fit snugly in there, I thought it just sat in there, so I got it and everything else went smoothly.

I'm sorry for al the mistakes in my typing, (if there are any..) I can't feel my fingers! haha

Here are some pics!

http://i197.photobucket.com/albums/aa283/braaup/100_2128.jpg

[Brauap]

http://i197.photobucket.com/albums/aa283/braaup/100_2129.jpg

Piston looks like it may need to be replaced, but I kinda figured the cylinder would too (be honed/bored) after sucking in all that stuff @ ROTR (Rumble on the Ridge (the riding trip where my air box came off))

[Brauap]

http://i197.photobucket.com/albums/aa283/braaup/100_2130.jpg

But my cylinder is smooth as glass, however, I will get it honed.. :rolleyes: haha

[Brauap]

http://i197.photobucket.com/albums/aa283/braaup/100_2131.jpg

These are what my vavles looked like (everthing had quite a bit of carbon build up.. :confused:

And in this picture are my new favorite gloves.. EVER! There soo nice, and help keep my hands warm!

[Brauap]

http://i197.photobucket.com/albums/aa283/braaup/100_2132.jpg

Close(r) up of the vavles..

[Brauap]

http://i197.photobucket.com/albums/aa283/braaup/100_2135.jpg

My 2 favorite things at the time.. and the hat thats not in the pic, because it was busy doing its job!

[Honda#4]

Looks good Colten, take the time now to clean the rest of the motor if you have the time. Make sure to scrape any gasket residue left on by the base gasket and by the clutch cover if you ever take that apart.

Make sure that when you go to put the base gasket on make sure it seals all around otherwise you'll end up like me and have the motor all in and everything and come to find out it leaks so just alittle reminder.

Other than that good job and keep up the progress. Seems easy right?

[Brauap]

http://i197.photobucket.com/albums/aa283/braaup/100_2136.jpg

Uhhhh.... I hate snow.. it makes everything miserable to work on!! :(

[Brauap]

Originally posted by Honda#4
Looks good Colten, take the time now to clean the rest of the motor if you have the time. Make sure to scrape any gasket residue left on by the base gasket and by the clutch cover if you ever take that apart.

Make sure that when you go to put the base gasket on make sure it seals all around otherwise you'll end up like me and have the motor all in and everything and come to find out it leaks so just alittle reminder.

Other than that good job and keep up the progress. Seems easy right?

Yea, I am going to clean it up very good. I am also thinking about sanding it all down too (with about 400-600 grit (wet)) and repainting it so it looks all nice.

How can I make sure it seals? I would absolutly die if I had to tare it all down again!!!!1!!one!! haha

And yea, it is pretty easy, fun, and relaxing. Thanks for encourging me to do it! Now, I have learned a whole lot, while having fun!

[Honda#4]

Basically put the gasket on but take the dowels that are on the motor off cuz sometimes the gasket tends to be a bit bigger around them areas then just put the dowels back in, make sure the gasket looks flat all around and not have any bends and you should be good.

I made the mistake though of putting some gasket sealer on and it made my gasket wet so thats why oil was leaking, biggest lesson I learned tearing my motor apart.

[sc400ex_rider]

ya that head looks like you were burnin some oil. your lucky one of the exhaust studs in the head didnt break thats a pain in the aaazzzz. you def need to replace the valve seals to.

[leasureryan]

Honda makes a top end kit for the 400ex that is like $40 for EVERYTHING! Valve seals, all 3 exhaust gaskets, all o-rings, head, base, etc etc. And we all know that the head gasket alone costs $30...so why not buy "Gasket kit A" which can be found on the first few pages of the parts fiche. I will get you a part #

06111-HN1-010 ....gasket kit A

also, use the CRF450 chain...it cost $39 as opposed to the 400ex chain which is half as thick for $100...kinda silly how Honda opperates

CHAIN, CAM (112L) <<<CRF
14401-MEB-671


Also, replace the head gasket with an XR400 head gasket, it's thiner

GASKET, CYL HD <<<XR400
12251-MBV-013

[3or4HONDA]

Looks good Brauap!

I will be doing the same in about a month.

Thanks Ryan for the part numbers, I was going to have to look them up eventually.

I was wondering when changing the cam chain I imagine the left side cover gasket will have to be replaced correct?

P# 11395-KCY-671

[Brauap]

Is having a number '2' on the cam normal? Or does that mean it is aftermarket, like HC S2?

[storms400ex]

doesnt your other rebuilt thread say you were taking the engine in so it be done right??????????? just curious

[Brauap]

..I said I wanted it too, but I can't afford it with my 14 y.o sallery :blah:

And.. how much more do I have to tear down to get the timing chain off?

[hoogiesngrinder]

you need to pull the right crank case cover off (clutch cover), remove the clutch basket, then remove the primary drive gear nut. That should allow you to get the timing chain out. I don't remember if there were any short cuts...I guess if there was a short cut it wouldn't be called a short cut, it would be called the way.

[3or4HONDA]

ya yur right the right crankcase cover, i was thinking the chain was on the left side