Help please - P76 valve stem seal replacement

[mark2]

I've decided to have a go at replacing the inlet valve stem seals on a P76 engine I bought recently. It was blowing some smoke on startup and after idling. It still has the P76 heads.

Anyway, the new ebay valve spring compressor arrived today so away I went.

First drama was removing the cast rocker pivot thingys - the nuts ended up being whitworth! After removing the nuts, the cast pivot was broken - I dont know if I broke it by not undoing nuts evenly enough? Anyone have a spare one of these or know where I could get one?

http://www.aulro.com/afvb/attachment.php?attachmentid=13147&stc=1&d=1233047389




The spring compressor worked well along with the leakdown tester to hold the valve up and one dual valve spring was soon off.

http://www.aulro.com/afvb/attachment.php?attachmentid=13146&stc=1&d=1233047204


The existing seal was nothing more than a flat rubber washer which came off in the inner spring. Apart from it being fairly hard, I cant see it would seal well by design, given the tendency for it to ride up the valve stem.

http://www.aulro.com/afvb/attachment.php?attachmentid=13148&stc=1&d=1233047460

I then managed to bump a push rod which promptly dissapeared into the valley:mad:. I really dont want to have to remove the inlet manifold as it appears to use two gaskets per side, probably a sign of previous sealing dramas. Any ideas for getting the pushrod out, without removing the inlet manifold?

What would be a better type of stem seal? The valve guide has a step in it which would probably accomodate some type of boot seal, rather than the dodgy washer.

http://www.aulro.com/afvb/attachment.php?attachmentid=13149&stc=1&d=1233047506


The valves themselves have a slight amount of side play in the guide, is some movement normal?



Thanks in advance.

[Blknight.aus]

a magnet on a stick should recover the gone rod, sideways movement is bad and a sign that you should be K-lining.

I dont remember the exact specifics of the p76 but every seal Ive had to play with thus far is more cup like than washer like, is there any chance the youve just got the top of the whole seal and left something behind?

[mark2]

Pretty sure the washer was all there was.

So no sideways movement at all? Whats K-lining?

[Blknight.aus]

k lining is a process thats used to put a sleeve inside the valve guide.

it means heads off to do it but its worth it as they generally last longer than the normal guide and is easier on the valve stem.

From the photos of the guides it looks like it was ment to have one of the boot/metal cup type seals on it and thats what Id be looking at fitting

[BigJon]

I am just having a look around the net, apparently Datsun 1600 valve stem seals fit.

[karcraft1]

Early P76 engines used a stepped valve guide and used Mini Cooper S valve stem seals (AEG327). Later engines used a straight guide which used a special bucket style seal made esp for the P76.

With regard to the valley cover gasket - the engine was originally fiited with a tin type valley gasket like the Rover V8. They had no end of troubles with this, so they bonded gasket material to the metal gasket to seal around the inlet ports which fixed all the problems.

Hope this helps.:)

[Rangier Rover]

One reason why I dumped the P76 heads for Rover heads. Have to strip block to drill oil hole:( I have some good p76 rocker gear here if you need it. :)
If the heads are stuffed best to use Rangie or Rover V8 heads rather than spend a fortune on P76 heads.


Tony

[mark2]

:mad::mad::mad::mad::mad:

I never cease to be amazed at my ability to c*ck up a simple job.

I've just dropped the valve - into the cylinder which happened to be at BDC.

It helps to keep up the air supply when the collets are removed.......:mad:

So the manifold is coming off, along with the head.......

[p38arover]

k lining is a process thats used to put a sleeve inside the valve guide.

it means heads off to do it but its worth it as they generally last longer than the normal guide and is easier on the valve stem.

When I had the heads on my P38A serviced some time back, they fitted bronze guides.

When the engine was rebuilt by Bruce Davis Performance Landys, Bruce said he didn't like them (I forget the actual reasons) and fitted new OEM guides. They weren't that expensive.

This is a section from How to Power Tune Rover V8 Engines for Road and Track By Des Hammill which give the method the a good review:

http://books.google.com.au/books?id=gmSavy1RPxEC&pg=PA84&lpg=PA84&dq=k-line+valve&source=web&ots=nf2v1w7rxT&sig=mkVTGKdCNoSLW5MR7zx5XGP-Fy4&hl=en&sa=X&oi=book_result&resnum=9&ct=result

[mike 90 RR]

:mad::mad::mad::mad::mad:

I never cease to be amazed at my ability to c*ck up a simple job.

I've just dropped the valve - into the cylinder which happened to be at BDC.

It helps to keep up the air supply when the collets are removed.......:mad:

So the manifold is coming off, along with the head.......

:( Always move / rotate the piston to the top of the head when working on IT'S set of valves .... so as to avoid losing the valve if dropped :(

:(

[revor]

I've heard this same thing on the MG forums here in the States, while they mention the the rocker arrangment is better (read, in lots of HP applications)on the P76 heads, it is not worth the trouble of finding parts. While the P76 shortblock was the gnats ass the heads seemed to be a PITA.


One reason why I dumped the P76 heads for Rover heads. Have to strip block to drill oil hole:( I have some good p76 rocker gear here if you need it. :)
If the heads are stuffed best to use Rangie or Rover V8 heads rather than spend a fortune on P76 heads.


Tony

[Rangier Rover]

I've heard this same thing on the MG forums here in the States, while they mention the the rocker arrangment is better (read, in lots of HP applications)on the P76 heads, it is not worth the trouble of finding parts. While the P76 shortblock was the gnats ass the heads seemed to be a PITA.

In the States....:D...... Find some 64 Buick 300 heads:twisted:

[revor]

well yeah! That's the ultimate solution isn't it?
However we've come up with a nice solution to the lack of 300 heads and actually made some Rover big valve head that work.
The last ride I had with them was in in a Disco 4.0 with a mild cam and these heads, it would run 110 all day long regardless of the hills and bring home 17 MPG at the same time. That's at 4500 feet above sea level?

For a case of Toohey's Old shipped to my address I will gladly share he information (my last case just ran out!)
Really I'll try and get the full info and pass it along in the next day or so if you like. They work! Very well!

Sorry about the hijack mark 2 it was (in a sense) sort of relative.


In the States....:D...... Find some 64 Buick 300 heads:twisted:

[Waxenwane]

If you want some P76 heads that have been reco'd I have a pair.

[hodgo]

:mad::mad::mad::mad::mad:

I never cease to be amazed at my ability to c*ck up a simple job.

I've just dropped the valve - into the cylinder which happened to be at BDC.

It helps to keep up the air supply when the collets are removed.......:mad:

So the manifold is coming off, along with the head.......
__________________________________________________ _____________


When replaing valve seals Instead of using air to keep the valves up, remove the spark plugs and feed a small dia rope in (that blue and yellow telcom rope is very good ) them wind the crank shaft by hand until it wont go any further no more droped valves.
A machanic in Vietnam taugh me this trick.

Hodgo

[stage one]

Sorry to here about that dropped valve mike! I know its a bit late now, but next time, try feeding some thin, greased rope through the plug hole when the engines at bdc, then turn it up to tdc or near to. Make sure you leave the end of the rope hanging out! You don't need speacial tools to change srings and seals that way either. Oh, and in my expreince, I've found most the time(every time really) you pull the heads off a motor because it's smokeing, you find out the engine needs a rebuild. Once I changed the oil in an old 360val I'd just bought, only to find after a few Ks, it stared blowing MASSIVE smoke clouds! An old engine that hasn't seen a oil change for a long long time forms carbon/sludge seals around the rings somtimes, when you change the oil it washes these out. :)

[Blknight.aus]

When I had the heads on my P38A serviced some time back, they fitted bronze guides.

When the engine was rebuilt by Bruce Davis Performance Landys, Bruce said he didn't like them (I forget the actual reasons) and fitted new OEM guides. They weren't that expensive.

This is a section from How to Power Tune Rover V8 Engines for Road and Track By Des Hammill which give the method the a good review:

How to Power Tune Rover V8 Engines ... - Google Book Search (http://books.google.com.au/books?id=gmSavy1RPxEC&pg=PA84&lpg=PA84&dq=k-line+valve&source=web&ots=nf2v1w7rxT&sig=mkVTGKdCNoSLW5MR7zx5XGP-Fy4&hl=en&sa=X&oi=book_result&resnum=9&ct=result)


excelent reference, but its worth noting, theres more than one type of K liner and you need to pick the one most relevent to your intended or actual application.

[mark2]

:( Always move / rotate the piston to the top of the head when working on IT'S set of valves .... so as to avoid losing the valve if dropped :(

:(

I had it at TDC (well, close to it but obviously not close enough) and when I pressurised the cylinder, it spun to BDC. That didnt worry me at the time as the air was still doing a good job holding the valve.......lesson learnt.

The head is now off. Bores look good - still plenty of hone marks visible.

Compression pressures were good (170-180, cold, after 4 cranks) and max leakdown was 12%, most were around 7%. Engine vacuum at idle was 21" Hg. I'm hoping that there's still some life in it yet before major $$ need to be spent. Aparently it's only done about 30k since a rebuild but it was well overdue for an oil change when I acquired it. Was also a small amount of dust in the carby choke horn - I've never seen a Holley with a round paper air cleaner seal properly yet. Thats a good enough reason in itself not to use a Holley on an off-road vehicle.

Got quoted $190 for a VRS gasket set today :eek:, looks like it might be cheaper to source the few gaskets I need separately. I really only need a composite head gasket and a valley gasket/inlet manifold gasket.

[Rangier Rover]

I had it at TDC (well, close to it but obviously not close enough) and when I pressurised the cylinder, it spun to BDC. That didnt worry me at the time as the air was still doing a good job holding the valve.......lesson learnt.

The head is now off. Bores look good - still plenty of hone marks visible.

Compression pressures were good (170-180, cold, after 4 cranks) and max leakdown was 12%, most were around 7%. Engine vacuum at idle was 21" Hg. I'm hoping that there's still some life in it yet before major $$ need to be spent. Aparently it's only done about 30k since a rebuild but it was well overdue for an oil change when I acquired it. Was also a small amount of dust in the carby choke horn - I've never seen a Holley with a round paper air cleaner seal properly yet. Thats a good enough reason in itself not to use a Holley on an off-road vehicle.

Got quoted $190 for a VRS gasket set today :eek:, looks like it might be cheaper to source the few gaskets I need separately. I really only need a composite head gasket and a valley gasket/inlet manifold gasket.

You will only need a P76 VAlley gasket. Rover will do the rest.
Are you you useing P76 heads again? If you need the rocker gear parts I have some spares here.

Tony

[mark2]

I pickup up a 10 bolt Rover head gasket today. After measuring it at home, the fire ring diameter is about 6mm bigger in diameter than my bore size - its obviously a gasket for a 3.9 which has a bore of 94mm:mad:

Will it be OK to use a gasket which is too big around the bores or should I try and track down a P76 gasket?

[Rangier Rover]

I pickup up a 10 bolt Rover head gasket today. After measuring it at home, the fire ring diameter is about 6mm bigger in diameter than my bore size - its obviously a gasket for a 3.9 which has a bore of 94mm:mad:

Will it be OK to use a gasket which is too big around the bores or should I try and track down a P76 gasket?
Would work but untidy:eek:. You need a 3.5 gasket. 3.5 and 4.4 have same bore size. Only 3.5 pistons to high in compession for 4.4 on ULP.


Tony

[LOVEMYRANGIE]

:mad::mad::mad::mad::mad:

I never cease to be amazed at my ability to c*ck up a simple job.

I've just dropped the valve - into the cylinder which happened to be at BDC.

It helps to keep up the air supply when the collets are removed.......:mad:

So the manifold is coming off, along with the head.......

For the sake of future reference.......

PUT EACH PISTON @ TDC WHEN USING ON HEAD SPRING COMPRESSORS!!!!!!
All it takes is removing 8 spark plugs!!!
:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D:D

[PLR]

G`day Mark2 ,

Felpro make a composite gasket for a 3.5 actually came about because of the Buick heritage , i think , well Felpro and USA go together .
Commonly used on Rovers , they are 14 bolt but won`t worry the 4.4 unless 45 thou compressed is too thick , possibly REPCO or similar can supply . There is a thinner 3.5 composite that is similar to the thinner 3.9 type composite both 14 bolt , they would need to come from a Rover aftermarket type business , i think .

Repco or similar may still be able to supply gaskets for a 4.4 at 1 time Repco had a small interest in them .

Compression pressure says it`s most likely a P76 and not a Terrier , though if it`s been rebuilt anything could have been fitted .

Think you`ll find straight 6 cylinder holden bits will work for your broken bits probably V8s also but 6s should work , possibly the stem seals also .

Wouldn`t been to concerned about dropping the valve , next time you use it you`ll know to be organised and put it back together almost as soon as you have it apart then so long as the air compressor holds , so does the valve and it doesn`t matter where the piston is .

Whenever i use one on an unknown engine i usually connect the compressor up and pressurize but only note the time it takes for the compressor to kick in , this way i get an idea of the engine and also the amount of time to play with .

Cheers

edit = forgot to mention if for any reason it needs to be apart for any length of time fit a small O ring to the valve stem then it doesn`t matter what happens the valve can`t be lost .

[BigJon]

PUT EACH PISTON @ TDC WHEN USING ON HEAD SPRING COMPRESSORS!!!!!!



All at the same time? :p

[LOVEMYRANGIE]

All at the same time? :p

One can achieve anything with a little stooooopidity and a Toymota owner doing your work for you.........:p