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Head re-assembly

Posted: Mon Nov 29, 2010 9:12 pm
by Cavman
Good evening one and all,
this question kind of follows on from a recent thread of mine about overheating problems. After much testing and replacing bits it was concluded that the head gasket on my 2litre mk1 cav (sorry, still not a V8 ) had indeed blown and would need sorting. So I bit the bullet and whipped the head off and sent it to my local engine machining place for checking and a skim if needed. It did need an 8 thou skim so they removed the rockers and tappets, skimmed it but were not then sure about the re-assembly process of the rockers as it may have to be done in a certain order that they were unsure of and didn't want to knacker anything. So I told them to leave it and I'd put it all back together myself. When I collected it this afternoon all the rockers, washers and nuts were loose in a box all together and tappets all together in a bag. I asked them if they knew which came off/out of where and they said it didn't matter as they're all identical and the tappets are hydraulic. I wasn't convinced, and still am not. the Haynes manual says to store them in such a way as to ensure they can go back EXACTLY where they came from, this has also always been my belief on the subject. Can someone please re-assure me that the machine shop haven't buggered my head up by not labelling everything?? either that or re-assure me that I have just cause to go back and kick up a stink?!
FYI the rockers are all individual (i.e. no rocker shaft) and it's cam in head if that makes any difference?
Also, and I realise this is likely to be pure ball-park guess work, but 8 thou seems not very much to me, is this likely to cause problems with an interference stroke engine, as this one is?

many thanks in advance to the gurus! :D

Posted: Mon Nov 29, 2010 9:30 pm
by softdash3.9
I don't think the 8 thou skim will cause any engine issues

It would have been nice to put them back as they were :roll: I know my machine shop would have done that :wink: would suggest going elsewhere in future

As long as there isn't any significant wear on any individual items I would expect it to be OK, the hydraulic followers will take up the slack.

I must point out that my experience is with small block Vauxhall Nova engines (1.3's ) rather than the CIH engine you have.

Unfortunately you can't put it back as it was, the Haynes manual I expect will always say ID components and put them back, as it is good engineering practice, which you would expect a machine shop to know :roll:

If anyone think my thoughts are wrong or have better knowledge of the engine, please pipe up :wink:

Posted: Mon Nov 29, 2010 10:21 pm
by gelmonkey
James
Don't go back to that machine shop as they sound like complete w@nkers!!!
You should always put the followers back in the same holes they came from but in this case you are up the poo creek without the propulsion stick.

You are just going to have to put them back in and hope for the best,they are self adjusting but you will have to follow the pre load settings as per the Haynes manual.
This is quite important to get right as the engine will sound like a bag of bolts if not done correctly.
I can always send a copy of this up to you(the pre load setting section not the whole book)
The skim will not affect anything apart from a minimal raise in the compression ratio.
There will be no contact between parts so no worries.
The skim will have just squared the head nicely.
Grab some free horsepower and gas flow the head and port match the gaskets and inlet manifols whilst its off.
Should gain approx 10/12 bhp just by doing this.
Any problems judt give me a shout ,you have my number.

Cheers
P

Posted: Mon Nov 29, 2010 10:45 pm
by Cavman
thanks guys, it is as I thought. :-(
bit pi$$ed off but not much I can do now.
I'll gaffer it all back together this week sometime and hope for the best.

as for free HP, :D :D :D :lol:

Posted: Wed Dec 01, 2010 2:59 am
by RoverP6B
Hello Cavman,

Seeing as the machine shop mixed up all the lifters (tappets), the major downside now and through no fault of your own is, when the wrong lifter starts running against a different lobe, both and especially the lobe is going to be very quickly worn away.. :shock: I am talking only a few thousand miles at best.

The only real option that you have now is to replace all the lifters and fit a new camshaft too. Camshaft and lifters work as sets from new, each work hardening the other and forming an individual working relationship between each lifter and its own respective lobe.

The machine shop should cover your additional expenses too through their incompetence.

Ron.

Posted: Wed Dec 01, 2010 5:44 pm
by Cavman
Seriously??!!! :shock: :shock:

A few thousand miles? balls. :( :evil:


Thanks though Ron, that is useful info. just saddening too....

Posted: Wed Dec 01, 2010 7:20 pm
by kiwicar
Yes a very few thousand miles
Mike

Posted: Wed Dec 01, 2010 11:19 pm
by bigaldart
I have replaced the tappets on one of these engines with no issues, they are fairly cheap so I would replace the tappets with new and run it. Just my 2 pence

Alan

Posted: Wed Dec 01, 2010 11:27 pm
by gelmonkey
James
Try Vauxhall Green parts they may have a set of followers at cheap prices.
P

Posted: Fri Dec 03, 2010 7:35 am
by RoverP6B
bigaldart wrote,...
I have replaced the tappets on one of these engines with no issues, they are fairly cheap so I would replace the tappets with new and run it.
Hello Alan,

How many miles did the camshaft have on it when you replaced the lifters? How many miles does it have on it now?

You are the only person that I have heard of who has done this, so your findings are of interest.

Ron.

Posted: Fri Dec 03, 2010 8:56 pm
by Cavman
Ok, a quick update.
I went back to the machine shop today and to cut a long story short it transpires that they have over 40 years experience in rebuilding these "old style" cast iron heads (vauxhall CIH, ford CVH etc..) and they've never ID'd and matched parts when rebuilding. They claim to never have had a problem. They admit that this isn't what the manuals say but that the manuals are old-school and have been superseded by the experience of the engine rebuilding trade, and that is that it makes no difference so no-one bothers. With this in mind there was nothing much more they could do, they could rebuild it for me but would have to charge me for the time and wouldn't guarantee it without a new cam and followers being fitted as using old parts isn't guarantee-able.
Basically I'm where I was before and, sincerely with no disrespect to anybody, don't know who to believe. I know and trust some of you personally and trust the rest of you by association. I think I'm going to fit new lifters as Alan suggested, then just hope and see what happens. If it dies soon then at least I'll have learnt something and it will spur me on the build the V8!!
many thanks for your responses,
James :)

Posted: Sat Dec 04, 2010 12:39 am
by bigaldart
Hi Ron

The cam had 130,000 on it to start with and I did another 25,000 before the car got wrecked outside my front door while parked. Long story but was running great, always had a problem with breathing and tried a lot of things to cure it, ultimately decided it was the nature of the beast and due to the oil level on the dipstick being too high. Kept it at the level it wanted and changed more often and it didn't spit any out anymore

Alan

Posted: Sat Dec 04, 2010 7:40 am
by kiwicar
Hi James
My experience of this is with 1 rover build and one Triumph 1500. With the rover I changed lifters because I had a rattley lifter, I changed it for a new one and it worked for a short time, then I started getting filings in the oil as the cam lobe collapsed, now it could have been a duff lobe causing the original rattle and infact it was not a case of the changing the lifter causing it to fail.
With the triumph through stupidity I got confused and I am pretty sure I got 2 swaped over and had 2 lobes fail, however the 1500 was a particullaly rubbish design and it was an uprated cam that put the engine under more strain.
If I were you I would listen to those who have direct experience of the engine you have, The valve train will be different in detail to the rover and the triumph, I have heard that generally OHC engines arn't bothered about matching cam lobes and lifters because the valve train is far less laoded. Just bare in mind it generally can be an issue and keep an eye on the lobes (by looking for metal bits in the oil).
Best regards
Mike

Posted: Sat Dec 04, 2010 11:47 am
by Cavman
Thanks Mike,
reassuring and sensible words, particularly keeping an eye out for filings, might invest in a magnetic sump plugs just in case! I'm putting it all back together today (assuming my toes and fingers don't die and fall off, it's pretty nippy out!! :lol: )
If folks are interested I'll update this as the miles roll on, just for reference's sake really.

James

Posted: Sat Dec 04, 2010 11:57 am
by sidecar
You could bung in some ZDDP additive for the first couple of oil changes.

This should help stop any nasty cam lobe grinding whilst everything beds back in.