How to replace valve seals?

[dirtrider77]

Well i traded my blown up banshee for a 01 416ex with stage 2 Hot Cam and weisco 11:1 piston

anyways it smokes a little more than it should, not bad but i want it not smoking and im going to tear it apart and just install new gaskets, rings and valve seals.

however ive never installed valve seals before.

someone please care to explain or give me a link on installation of valve seals?

i searched but came up empty handed, so sorry if its somewhere on here, i just failed to find it hah

thanks again

[bherriman]

I'm not sure how familiar you are with a 4-stroke. But if you have had a head apart before, its simple. To keep it short and sweet, You will have to remove the head (which will come off anyway for the rings), use a spring compressor to compress the valve springs, remove the retainer and keepers. You then remove the spring and push the valve out. The valve seals simply push over the top of the valve guide, after you remove the old ones of course. It's good practice to wire brush all the carbon off the valves and lap them back in properly since you've got it all apart anyways.

[dirtrider77]

thanks! ive rebuilt many 4strkes before but never had to fool with valve seals and i just wanted to make sure there was nothing special i needed to watch out for!

thanks again

[bherriman]

Yea, if you understand the concept of a 4 stroker, you'll do just fine!

[dirtrider77]

sweet, thanks man

[brokenmike]

I know you are gonna take the head off anyways to do the rings but it is possible to replace the valve seals without pulling the head off. You need an adapter to put compressed air in the cylinder and pressureize it and then tAke off the valve springs

[CJM]

Originally posted by brokenmike
I know you are gonna take the head off anyways to do the rings but it is possible to replace the valve seals without pulling the head off. You need an adapter to put compressed air in the cylinder and pressureize it and then tAke off the valve springs

Where does it say you need a compressor to pressurize it? I took it all apart with a homemade valve compressor no less and had no issues at all.

[brokenmike]

That is with the head still on the motor. You pressurize the cylinder and it keeps the valves from dropping into the cylinder. I learned that trick from doing valve seals on cars and trucks

[dirtrider77]

Originally posted by brokenmike
That is with the head still on the motor.

well since im replacing the rings too, im pretty sure it would be easier to forget all the air crap ha

but nevertheless, good idea

[rubbersdown]

Originally posted by brokenmike
That is with the head still on the motor. You pressurize the cylinder and it keeps the valves from dropping into the cylinder. I learned that trick from doing valve seals on cars and trucks

Ive done it a million times on cars and trucks but answer me this... You can get the spring off by putting a socket on it and smacking it and keepers come out BUT how do you get the springs compressed and back on? Its easy in cars because the compressor bolts to the head itself using a rocker stud but on an ATV the compressors dont do that, they go all the way around the head like a c-clamp and push up on the valve from the bottom side. Im just curious as to how you did it or have you just done it on cars and never an ATV? Just doesnt seem possible to me without the huge hassle of making some super custom tool to do it.

[dirtrider77]

rubbers down, they make a tool that is like a vice that clamps on both sides of the spring, then you twist a knob and it compresses the spring and keeps it compressed.

i think that answers your question

[brokenmike]

I had used the part of the atv valve spring compressor that would normally go on the valve spring to compress it, and used something that fit on the end and I just pushed the spring down and inserted the keepers. I only weigh 130. It wasnt bad.

[rubbersdown]

Originally posted by dirtrider77
rubbers down, they make a tool that is like a vice that clamps on both sides of the spring, then you twist a knob and it compresses the spring and keeps it compressed.

i think that answers your question

never seen one of those! You not afraid of compressing the spring too much and it loosing tension? (It happens lol)
Ima have to get me one of those, thatd make life lots easier, you have a pic of one?

[dirtrider77]

Heres a link...there pretty cheap, and no your not going to have the spring compressed for a long period of time....30 minutes at most!

copy and paste this number into fleabay

270659690882

[Pipeless416]

when i replaced my valve seals, i simply used a large c clamp, and a thin piece of steel (0.10") that i bent at a 90 degree angle. since pictures are worth a thousand words, here's a few that may help you out.

[Pipeless416]

other side

[Pipeless416]

and of course, here is what you'll end up with. sorry it's blurry.. these are all old cell phone pictures.

[dirtrider77]

thanks pipeless

you are a very ingenuitive man haha

[Pipeless416]

Originally posted by dirtrider77
thanks pipeless

you are a very ingenuitive man haha

no problem. i'd like to call myself frugal. :p :blah:

[CJM]

I tried the hammer and tap method on mine and another and I tried using my 220lbs of weight, it wont work as the valve springs are VERY stiff.

I made a homemade tool using a large c-clamp and a pc of pipe I cut like pipeless's pics. If I had to do it again Id buy the 30 dollar tusk one from rocky mtn, just makes it easier overall.

[dirtrider77]

Originally posted by Pipeless416
no problem. i'd like to call myself frugal. :p :blah:

yeah that sounds better hah

[rubbersdown]

[QUOTE]Originally posted by dirtrider77
Heres a link...there pretty cheap, and no your not going to have the spring compressed for a long period of time....30 minutes at most!

copy and paste this number into fleabay

270659690882 [/QUOTE

ohhhh one of those things got ya. I personally would not use that. Its not the time that the spring is compressed that hurts it, its the amount its compressed. you are not supposed to compress the spring farther than you have to to get the keepers in. Using that style of compressor having to put the leg of it on the bottom of the spring means you have to compress the spring that much further to get the keepers in and it will end up ruining your springs because they lose tension when you do that. My .02 but it also states this in any manual for any 4 stroke bike or ATV.
Straight from the 400ex manual: "To prevent loss of tension, do not compress the
valve springs more than necessary to install the cotters."

[rubbersdown]

Originally posted by CJM
I tried the hammer and tap method on mine and another and I tried using my 220lbs of weight, it wont work as the valve springs are VERY stiff.

I made a homemade tool using a large c-clamp and a pc of pipe I cut like pipeless's pics. If I had to do it again Id buy the 30 dollar tusk one from rocky mtn, just makes it easier overall.

agreed, if you are able to hold down your springs and put your keepers in by hand like the guy on the previous page said then you need new springs stat! lol.

[dirtrider77]

oh yeah im not arguing that you should keep spring compression time minimal, i just showed you that tool because i thought that the question you asked earlier was best solved by that....personally when installing valves i use a notched tool that goes on the valve and i use my own body weight to compress while someone else puts on the keeper

[dirtrider77]

also i will add its not me compressing the springs by hand with the tool haha im no where strong enough, i just put the keepers on

[rubbersdown]

Originally posted by dirtrider77
oh yeah im not arguing that you should keep spring compression time minimal, i just showed you that tool because i thought that the question you asked earlier was best solved by that....personally when installing valves i use a notched tool that goes on the valve and i use my own body weight to compress while someone else puts on the keeper

Oh yah its cool, just sayin that so people are careful and dont hurt there springs if they choose to do it that way. For the 400ex I use just a regular old c clamp style compressor with ends kind of like the tool you showed me but for bikes like my wife's ttr125 where the valves are set WAY in the head I just use a notched out piece of pipe or pvc like everyone else lol. I am going to invest in one of these though just to have it around because I have many bikes with many dif. sized valves lol...http://www.google.com/url?source=imgres&ct=img&q=http://www.chain-auto-tools.com/pics/AMR038E-1.jpg&sa=X&ei=WJbZTLGRFIPJnAfI-9zICA&ved=0CAQQ8wc4GA&usg=AFQjCNH_MZR5LpcFng2bJyTOUVjO8j3G0A

[dirtrider77]

item number for above tool:

160499456880

[rubbersdown]

changed the link to a pic but its item number 330488694616
my mothers husband has one and it works great on all valve sizes, well worth the $30

[dirtrider77]

and yea i need to invest in one of those, my neigbor gratuated from MMI Orlando and he was the best tool ever haha but now hes moving, so i need to invest in some of these specialty things

[Pipeless416]

while there is all this talk about compressing springs, now is a great time to check to see if they are still within the service limits. when i last rebuilt, mine were still ok, but since i run an aftermarket cam, i thought it was justifiable to replace them at that time. nobody likes floating valves ;) . $52 for peace of mind is well worth it in my opinion.

[dirtrider77]

Originally posted by Pipeless416
$52 for peace of mind is well worth it in my opinion.


exactyl! ha i just got the quad and when i tear into the motor, i might as well replace the rings, all gaskets and seals...and heck i might go ahead and throw a new piston in too lol....i want to do it all at once and be happy ha

its like rat rods....never did understand them lol half done