Doing The Valve Stem Seals

[SECURITY]

bugger that for a joke. Good that it works but how did you go about pressure testing the system?

Not too bad if you do the job for your own vehicle but it sucks now because I've had three people ask me to change their valve springs and seals over without removing the head. What's your email so I can send 'em your way lol.

was that pressure testing or pressurising?

i didnt know you had to pressure test anything.

if you're serious my email is in my profile.

[The Dan]

was that pressure testing or pressurising?

i didnt know you had to pressure test anything.

Just a pressure test through the port to ensure the stem seals are actually sealing.

Like I said, though...ok if you are doing it to your own car but not really the proper way or a good way to do it.

It's like changing camshafts over without removing the timing belt....sure it can be done but not a good way to do it.

[SECURITY]

i pulled out an extremely ugly one today. it looked pretty worn out from the inside, and was a complete prick to get off.

heres a pic, its not that clear, my phone cam couldnt focus on it that well:

[Cubes]

How many km's have they done Secur1ty?

[SECURITY]

180,000.

they were defiantly due for a change.

[SECURITY]

all done.

it wasnt a hard job. just make sure none of the hoses come loose on your compressor as it will cause you some huge dramas. if you dont have your piston at tdc and the compressor fails or a hose comes loose then you'll drop the valve in there.

also, the motor turns when you put the pressure on so just be careful of that, try keep the motor from turning somehow (maybe a breaker bar and 27mm socket). i didnt do this because im a bit of an impatient idiot (and it takes patience) but i went out and bought some oil cooler hose (capable of holding 120psi+) and some new heavy duty clamps for the compressor fittings and let the pressure run while pulling on it, it all checked out so i tightened it a little more then started working.

[Blitz]

Excellent work and a good read here Joe, well done

[tridentt150v]

Question: If a piston is a TDC and you loose pressure, would the valves fall out, or only down? that is, is the situation recoverable with needle pliers, bent bit of wire and/or a magnet to get the valve back up. I would have thought that at TDC the valve would rest on the piston and still be 'recoverable', but it'd be nice to know.

To stop the motor turning, in gear and handbrake on???? Or is there too much movement in the drive train?

Otherwise good thing, all those workshops out there will just have to pick their act up now!!

all done.

it wasnt a hard job. just make sure none of the hoses come loose on your compressor as it will cause you some huge dramas. if you dont have your piston at tdc and the compressor fails or a hose comes loose then you'll drop the valve in there.

also, the motor turns when you put the pressure on so just be careful of that, try keep the motor from turning somehow (maybe a breaker bar and 27mm socket). i didnt do this because im a bit of an impatient idiot (and it takes patience) but i went out and bought some oil cooler hose (capable of holding 120psi+) and some new heavy duty clamps for the compressor fittings and let the pressure run while pulling on it, it all checked out so i tightened it a little more then started working.

[Adriano]

If the piston is a tdc, the valve can only move dowm about 6 or 7 mm, and the crank shouldn't need to be held, only if its slightly off centre.

[T04GTR]

nice work joe. i was abit worried for you. but thaey look f**ked. all coked up and everything.

lol geting those collets back in is a fine art that you have to re-learn everytime you do it lol. there a kunt

[T04GTR]

yeah but thats 6 or 7mm more you have to compress the spring. and still need more to clear the collets.

[tridentt150v]

Yeah, i realise that you need to keep the valve in the fully closed position to do the work, but I was thinking along the lines of what if your compressor stopped, or the hose/fitting blew. Is the situation recoverable, and if the valve only drops a few mm then the answer is yes, it is recoverable, you won't loose a valve in the combustion chamber. Hell with only 6-7mm you won't even loose one inside the guide - unless you aren't at TDC for that cylinder, then your in the poo.

yeah but thats 6 or 7mm more you have to compress the spring. and still need more to clear the collets.

[SECURITY]

nice work joe. i was abit worried for you. but thaey look f**ked. all coked up and everything.

lol geting those collets back in is a fine art that you have to re-learn everytime you do it lol. there a kunt

yeah! the first few were a pain in the ass. but once you work out a system they all go in pretty easily. it took me around an hr to do the first 4 (i was pretty much teaching myself how to do them). then it took me around 1.5hrs to do the other 20 once i got my technique down.

you'll probably lose around 15-20mm of the valve if it drops in (dont forget the haad is domed and so are the pistons) but you've got around 20-30mm of the valve to play with if its fallen in.

[The Dan]

Otherwise good thing, all those workshops out there will just have to puck their act up now!!

Puck their act up? Surely you'd want them to do the job properly and thoroughly.

For the cost of a head gasket and inlet/exhaust gaskets, I would prefer to do the job properly. Plus the fact that removing the head actually takes the same time as doing it the other way and you can regrind the valve seats while you're there.

You won't get a decent workshop to change valve stem seals like that. Too much can go wrong and you can't test it afterwards so really it's a half arsed way to go about it.

I don't mean any disrespect to SECUR1TY by saying the above as I'm not directing it towards him. It is actually refreshing to see more people who'll get out there and try new things. Just making a point that when people ask me, or any respectable mechanic, to change stem seals like this...the answer will always be no.

[SECURITY]

so my results were a complete fluke?

i had very little background on how to do this, yet i did it without any problems at all. im not a qualified mechanic, im just a dude with a skyline that only needed new valve stem seals. my head gasket is 2000km old.

just because you dont do the job this way doesnt mean that no workshop does, i spoke to a few mechanics who didnt see any problem in doing it this way except for finding the right tool. then i got referred to a reputable workshop by an sau member to borrow their tool but ended up making my own.

it is a extremely cheaper way to do it. i paid $80 for a set of ACL valve stem seals, and $25 to make the tool. turn around time was alot quicker than getting a workshop to remove the head, buy a vrs kit and labour, and that would've cost around $800 easily. (vrs kit which includes valve stem seals costs around $250 trade price, and to do a head gasket ONLY costs around $600 to get done at a workshop).

the aim of this thread isnt to judge which way is better (although i still dont see any positives to wasting a perfectly good head gasket), but to tell and show other members its possible and doesnt need to cost shit loads to do.

[tridentt150v]

Puck their act up?

Sorry, fat fingers, I meant pick, pick their act up.............and no I don't think its a substitute for a head rebuild. This is not going to help stuffed valves, guides or head gaskets. But it could be used as SECUR1TY has to change seals in a freshly built top end, or to change valve springs, cups or collets etc.

Anyway if you want to lap the valves back in, you use a couple of teaspoons of ajax in the combustion chamber like everyone else does.......................lol :laughing-smiley-014:

[The Dan]

so my results were a complete fluke?

i had very little background on how to do this, yet i did it without any problems at all. im not a qualified mechanic, im just a dude with a skyline that only needed new valve stem seals. my head gasket is 2000km old.

just because you dont do the job this way doesnt mean that no workshop does, i spoke to a few mechanics who didnt see any problem in doing it this way except for finding the right tool. then i got referred to a reputable workshop by an sau member to borrow their tool but ended up making my own.

it is a extremely cheaper way to do it. i paid $80 for a set of ACL valve stem seals, and $25 to make the tool. turn around time was alot quicker than getting a workshop to remove the head, buy a vrs kit and labour, and that would've cost around $800 easily. (vrs kit which includes valve stem seals costs around $250 trade price, and to do a head gasket ONLY costs around $600 to get done at a workshop).

the aim of this thread isnt to judge which way is better (although i still dont see any positives to wasting a perfectly good head gasket), but to tell and show other members its possible and doesnt need to cost shit loads to do.

No I didn't say your results were a fluke and wasn't implying that you had done the wrong thing. I was commending you on a job well done and saying that it is good to see people actually having a go at doing stuff themselves. What I was disagreeing with was that some people are saying that workshops now have to pick up their act and do it this way to remain cost effective. The proper way is not always the cheapest.

As for the head gasket only having 2000ks on it....why were the stem seals not done then?

So just to re-cap so there is no confusion:

You did a great job and good work on reporting it all.

I CAN see why you did it that way afterwards but not sure why it wouldn't just get done with a head gasket to be thorough

I still stand by the fact that NO DECENT mechanic would do it that way to a customers car for the reason that it is only doing most of the job and not all.

[SECURITY]

well i did an engine rebuild and pretty much left the head untouched except for a shave. i got the vrs kit for $150 without the stem seals so i left them out.

the only problem i had with what you said was that it was half arsed. im sure that if there was a professional tool out there (and there is but not readily available in this country, which can be found HERE) you wouldnt think it was so dodgy.

as you seem like a decent mechanic i can understand that you are reluctant to try something like this. but its automotive innovation at its finest, i think

[The Dan]

well i did an engine rebuild and pretty much left the head untouched except for a shave. i got the vrs kit for $150 without the stem seals so i left them out.

the only problem i had with what you said was that it was half arsed. im sure that if there was a professional tool out there (and there is but not readily available in this country, which can be found HERE) you wouldnt think it was so dodgy.

as you seem like a decent mechanic i can understand that you are reluctant to try something like this. but its automotive innovation at its finest, i think

So that tool can pressure test the head to make sure the stem seals are sealing correctly? Just so you can determine whether it actually is a seal that is the problem and not a cracked guide.

I know what you're saying and can appreciate what you have done....it's not a new thing, and those tools have been around for some time (decades). In fact I use them to install valve springs (after running in a cam, then changing over to double springs). Things like that are ok but you have to consider it from a workshops point of view and that a warranty has to be given to some extent. Also it is dodgy to only do 90% of the job by not testing it to ensure there will be no other problems. Also it will save you time by not having to do it again if it does turn out to be a cracked guide.

[180or200]

Those guys who have attempted the seals while leaving the head on, how do you think this tool would go?