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Discussion Starter #1
Just to clear my head before I start stripping down the head, is this too much play? It's been a long time since I did a head job and my gut feeling says this is this is too much, but I wonder if this is ok as a short term until I source or fix a better head.

This head came out of a car with a burnt piston, I measured the play in wiggle positions and it varies from 15 thou to 25 thou in exhaust valves , inlets are much better and lot less play

If this is ok in short term solution I prefer to bolt this on and start using the car, but it needs to go through a MOT so will this cause emission issues?

I have a second cylinder head with worse play which I already started stripping it down but I prefer to fix it in my own time so that would mean car will have to be a non runner for much longer time.

Car will be used as a second run about car by mostly Mrs , nothing extreme.

 

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do the guides look oral holed , also if pull valve out more so mainly on a part of valve stem that has been outside of guide and in spring space does the movement reduce a lot if dose stick new set of valves in the exhaust side always wears most as stem seals drag crud in to them more and heat is more at top end,, borderline i would say from video ,, try the wear test on stem thats got no wear in it
 

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Discussion Starter #3
Yeah some of them have gone oval shaped, if I try to do the wiggle test sideways then not much play, most of the guides don't make that vacuum popping sound either.

But I've fitted the old stem seals and tried wiggling and seal seem to hold up to the pay ,ie it still keeps the seal with stem even with maximum wiggle, that's when I thought maybe I could use this as a temp measure.

Mike If you say it's borderline then I'm minded to take a chance and give it a go, you do these engines day in day out so no better person to take advice from.
 

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Discussion Starter #4
What issue can I face apart from blue smoke at start in these engines with worn guides? in theory they say burnt valves , broken valves and all kinds of stuff but in reality can this effect emissions in a MOT test?
 

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when stem seals go hard again will start smoking again, big issue is build up of crud on the valve seats and the risk that the dirt that was in there just before the rebuild is now gone and this dirt could very well be what stopped it from smoking and now its clean will let oil pass the seals,,
below link removal tool
or could use threaded bar and sockets and some heat maybe
 
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Discussion Starter #6
I made a similar tool, with bit of heat it came right out without any issues.




 

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Discussion Starter #7
when stem seals go hard again will start smoking again, big issue is build up of crud on the valve seats and the risk that the dirt that was in there just before the rebuild is now gone and this dirt could very well be what stopped it from smoking and now its clean will let oil pass the seals,,
below link removal tool
or could use threaded bar and sockets and some heat maybe
I'm leaning more and more towards doing this right and replacing them
 

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will add this if removing the guides before doing so measure the guide top to cylinder head on the valve spring side, also use full strength thread lock when installing new ones
 
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I'm leaning more and more towards doing this right and replacing them
to be honest i would as its such a pain when dont do it all and then next mot fails as burning oil or has a misfire due to valve seats leaking ,,,
i make such tools all the time for jobs proves you have understanding to be working on such jobs,, i use a press i made up with a 100 tonne 1.5 meter lift jack and RSJ beams and some bolts etc breaks it or removes it lol,
i also made up a tool for putting the vvt spring fingers back in the bucket slots old lever bar ground in a groove and bent a certain way cheaper than the £300 laser tools want for the tool to do same job, i also have a mini chuck on a cable to cut valve seats at speed can attach to valve stem ,, can also of guide a bit to tight use it to grind them in with fine paste and a drill, you can also use a long round drift and put a thick washer between it and valve stem reduces the distortion when hitting it hard
drift set below
 

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Discussion Starter #10
I saw you posted about the VVT springs on another thread , it give you great satisfaction when you come up with such ingenuity and when it pays off.

I should look to make a press as well , I don't have enough space in my tiny shed so I can't buy an off the shelf stand in press. no space.


I've been thinking if valve seat will be able to hold the load when pressing the guide in or not , the tool you posted goes in the valve seat so in theory that should be ok, I'm just being paranoid

I was thinking to cut a valve from it's stem and drill a hole in the middle and use it with my tool.

279678
 

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2008 Mini Cooper S hatchback,Automatic,Mello Yellow
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On a loctite note or permatex note. It behooves one to read in detail all the different notations about from the products they offer to the drying times.😐
Those products change over time. And are believe it or not molasses based. I myself am under the impression that 638 loctite is quality for such matters(as a D.I.Y. er). So don't my word for it.
http://tds.henkel.com/tds5/Studio/S...at=MTR&subformat=REAC&language=EN&plant=WERCS
In order to obtain that info I just downloaded the TDF read instruction on The "Henkel" website.
But it's like using youtube. The products they are offer are like the video youtube offers they are all there anything you want. You just have to know what to type or in this case a product number.
D.I.Y. er not professional! So you may want to check into what professionals use for that. Something like Loctite 603. Not sure?
 

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On a loctite note or permatex note. It behooves one to read in detail all the different notations about from the products they offer to the drying times.😐
Those products change over time. And are believe it or not molasses based. I myself am under the impression that 638 loctite is quality for such matters(as a D.I.Y. er). So don't my word for it.
http://tds.henkel.com/tds5/Studio/ShowPDF/243 NEW-EN?pid=638&format=MTR&subformat=REAC&language=EN&plant=WERCS
In order to obtain that info I just downloaded the TDF read instruction on The "Henkel" website.
But it's like using youtube. The products they are offer are like the video youtube offers they are all there anything you want. You just have to know what to type or in this case a product number.
D.I.Y. er not professional! So you may want to check into what professionals use for that. Something like Loctite 603. Not sure?
used more for its lubrication when still wet, and something you know will set hard,, as for setting times as soon as gets hot totally sets,, so can for extra piece of mind used heat gun or blow torch on the area but to be honest ones pressed in they never come out again anyway,, most machine shops with heavy duty press will prob just ram them in as its a interference fit,, on a DIY level its not common to do this job, but like anything always a work around
 
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They used 609 loctite or something like that on mine. Not a high or medium; a sleeve retainer compound. They had the machines to do it in the end.
There is no tutorial on the mini or anything in relevant size to those tiny valve guides whether it be a chevy cobalt or Cruz. So it much easy to ram in valve guides that are three times the size of yours.
I changed mine out for steel valve guides which should be shown in my" pre timing chain install" thread. I think? Which is probably a downgrade considering that is one place where mini did not cheat the quality. Anyways! It's runnin.
 

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They used 609 loctite or something like that on mine. Not a high or medium; a sleeve retainer compound. They had the machines to do it in the end.
There is no tutorial on the mini or anything in relevant size to those tiny valve guides whether it be a chevy cobalt or Cruz. So it much easy to ram in valve guides that are three times the size of yours.
I changed mine out for steel valve guides which should be shown in my" pre timing chain install" thread. I think? Which is probably a downgrade considering that is one place where mini did not cheat the quality. Anyways! It's runnin.
having a press that can set the travel is most of the battle, or as i do use some metal pipe cut to stop the travel just takes a bit of setting up on the first one then slide the head along the RSJ bed i made for my press,,, i would say to anyone the easy way is let a machine shop do the guides,, guy i use a lot £250 for guides and valves lapped in and skim but i try not to skim these heads as they dont have much meat on them to skim them past 0.60mm,, tend to clean them off with scotchbrite pad and then clean with brake cleaner then add well seal on block them lay gasket on the coat the gasket facing upwards then bang head on been doing it like this for over 10 years never had one back for head gasket issues maybe i'm just lucky lol
 
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Discussion Starter #16
having a press that can set the travel is most of the battle, or as i do use some metal pipe cut to stop the travel just takes a bit of setting up on the first one then slide the head along the RSJ bed i made for my press,,, i would say to anyone the easy way is let a machine shop do the guides,, guy i use a lot £250 for guides and valves lapped in and skim but i try not to skim these heads as they dont have much meat on them to skim them past 0.60mm,, tend to clean them off with scotchbrite pad and then clean with brake cleaner then add well seal on block them lay gasket on the coat the gasket facing upwards then bang head on been doing it like this for over 10 years never had one back for head gasket issues maybe i'm just lucky lol
This is what I plan to do when fitting guides, will cut a little pipe to the exact length and that will stop the guide with exact height sticking out.

I too would go to a machine shop, this is too much hassle, but I can't find any is the problem lol.
 

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That's what Im saying take that to someone. I took cylinder head in and they hot tanked it,resurfaced it. Even though I was jubilantly against it(I know I need to have faith in them which I did in the end and they did a excellent job!). Then they pushed in the bronze valve guides I bought In the head.
I timed the car wrong and wrecked the bronze valve guides splitting them into four on the circumference of the round end as seen after removing the valves. Then took it back to them.
Had a new set of steel guides they put into it. At no extra cost. I replaced the valves with new obliviously I did not need to lap them.
Initial cost. Was
1. hot tank
2. valve seats were done.
3. valve guides (drilling included)
4. assembly
5. re surfaced.
all for 700 dollars U.S.
Which really was cheap. considering they angle drilled holes for the valve guides to go in at a different angle and degree from what is original to the cylinder head. In order to make it correct to what it was to begin with I am sure(proper valve guide fitment).
 

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This is what I plan to do when fitting guides, will cut a little pipe to the exact length and that will stop the guide with exact height sticking out.

I too would go to a machine shop, this is too much hassle, but I can't find any is the problem lol.
good idea that will work i do it with a press and preset the travel on the press in same way , another good idea but my wife goes nuts is when installing new ones put head in oven 150c for couple of hours and put the guides in the freezer over night should just drop in to place like that
 

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Then I used that blue paint stuff on the exhaust and gasket & port matched that to my regular cooper s exhaust manifold not my JCW exhaust manifold. Then ported and polished the exhaust port myself. Making sure not to do the intakes on that head. I has the dimples to in the intake ports I think. Which means that it could suffer from condensation easily. As I will not be TRACKING the car.
 

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Discussion Starter #20
good idea that will work i do it with a press and preset the travel on the press in same way , another good idea but my wife goes nuts is when installing new ones put head in oven 200c for couple of hours and put the guides in the freezer over night should just drop in to place like that
Ha ha yes!, I've been reading the oven and freezer method and intend to do it when fitting, now that the Christmas is over she wouldn't mind I think , the plus this is going to be her car so she'll be ok.
 
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