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Admin · Posted: Mon Apr 28, 2008 10:29 pm Post subject:

Hi

From memory late 16V engines (the ones fitted to the 145/6) had cams set up to open the valves at a slightly different time. Possible you have some of those cams.

All the best

Keith
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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

mine is K reg, 92, any idea on pulley tensioner springs?
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lee16v · Posted: Tue Apr 29, 2008 5:17 pm Post subject:

I hooked the spring on its peg and then pulled the tensioner down onto the bolt. Found this to be the easiest way as that spring is hard!

BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

ok, what about getting them off Laughing

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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

Some pics of my head, that huge amount of cam movement was due to the cams coming to rest in the position where all valves are closed. Unluckily it just caught 1 valve I think. If cams are turned anti clockwise then all valves open at the same time and equally when fully open

ns head front cylinder showing valve gap

ns head front cylinder showing mark on valve

ns head front cylinder showing inlet valves equally fully open

ns head rear cylinder

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lee16v · Posted: Wed Apr 30, 2008 8:02 pm Post subject:

BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

Will do, just a little tricky as the engine is in the bay with radiator on, even a little awkward when cross member is dropped, I will persevere.

Another question, is it possible to change a valve with out dismantling the head. Can you use a valve spring compressor after removing the cams and bucket? Or is there no way to gain access to the collet?
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lee16v · Posted: Fri May 09, 2008 9:00 pm Post subject:

I would have thought that changing a valve would be nigh on impossible.
I made a tool to compress the spring and needed a G clamp to compress it so that would have been out of the question due to clearance. Even if you do have another way of getting the valve out, getting the collets back on is tricky enough with the head upright let alone on its side.

BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

thought as buch, but thought id ask, thanks.
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Admin · Posted: Mon May 12, 2008 10:34 am Post subject:

Hi

You might be able to change a spring, but no way a valve ( how would you get it out?).

It is not an uncommon bodge. Hold the valve closed (either compressed air in the plug hole, or more of a bodge and put a long piece of string through the plug hole and then turn the engine to TDC) and then push on the spring to release the collets.

All the best

Keith
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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

hey keith, i think you misunderstood my question.
The head is off the block, I have access to a valve spring compressor.
I have not taken anything apart on the head.
I think you were thinking the head is still on and what you suggested was to just change a valve spring. Laughing

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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

Any suggestions on how to get the front cam cap off? The one with the oil seal.
I have tried tapping with a rubber and plastic hammer, tried putting the bolts on but loose and tapping them. I have removed the cam pulleys but am worried about bending the cam if i hit it hard.
Any suggestions??
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lee16v · Posted: Mon May 12, 2008 6:10 pm Post subject:

Do as you've done before.... leave the nuts on slightly undone and give it a firm knock with a copper drift and it will come off. Seems harsh but you aren't going to do any damage to the cam shaft unless you start getting the sledge hammer out!!

BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

Been doing that with no joy Crying or Very sad

Thats why i asked about hitting the cam from block towards head direction. I'm scared
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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

Lee
whats a copper drift? hammer?
Going to have another bash at ti today, pun intended Smile

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lee16v · Posted: Wed May 14, 2008 5:20 pm Post subject:

BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

ahhh i c said the blind man. Thanks
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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

Update.
I got the cam out by using a rubber/plastic hammer and hitting it from block to head direction, the cam came out but the cam oil seal left rubber in the recess. I removed the offending valve and didn’t replace the cam, I didn’t touch the other cam. The head was now ready for pickup with no metal cam cover back plate, no cam pulleys, one valve removed, one cam removed, throttle bodies removed and tensioner removed..

The head was picked up Friday morning, I had previously discussed with the garage that I want a pressure test done, to check that no other valves are bent, I had already been around with the head and to keep the cost down he asked me to do what I have done above. The head came back after mid day, they had removed the other valve in the cylinder that had a bent valve as it was bent as well. The other buckets for the removed cam were left loose in the box, not labelled as to which valve they were for.

Am I being too picky or should they have labelled the buckets, or at least put them back where they came from?
I ask this because every mechanic I have seen when working on a head or engine always lays out components in the order and position they came from so they can go back in the same place.
I was then told that the other valves could be holding pressure as the 2 springs could be strong enough to make a seal even if the valves are slightly bent and were to hard to move and do I want them removed to check. I thought I said I wanted it pressure tested to check for bent valves??? So the head went back.
I got a phone call a little later confirming what I wanted, even though he had seen the head and could see that all valves are closed, I even asked him if he wanted the pulley attached and it was agreed that the whole head will be stripped and all valves checked.

I’m now worried that that things like collets, springs, buckets will all be mixed up, is this something to worry about?
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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

update
only 2 exhaust valves are bent, picking them up from my alfa garage who race prepair 33s. They told me as long as there are no cracks in the guides, all will be ok and that it shouldnt matter if things are mixed but would be better if not.
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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

update, picked up 2 second hand exhaust valves for £10 Laughing

Will take them to the head place and get them to grind them in as i dont have a cleaning tank and would hate to leave some paste somewhere.
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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

Dear Alfa diary,
Today I took my valves to the head place who grinded them and will then seated them in. He said that he stripped the other cam and did the same, the valves are clean, but im wondering if they can be cleaned without removing them. I asked how he got the cam out, as the side I tried to get out wouldn’t come out without hitting the cam as the cam oil seal bearing was jammed in, damaging the oil seal in the process, I think. He said he undid it and it just came out, I find this hard to believe, anyone else experienced this?
I took my cam pulley tensioners to a place to get the old pulleys removed and the new ones pressed in. The metal broke, so I now have to order the complete pulley tensioners Crying or Very sad

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ZeNiTh-PbArM · Posted: Wed May 21, 2008 7:16 pm Post subject:

hi, looks like you're out of luck, never managed to break those castings, besides pins do not need to be pressed in an out with a bench press, the use of a vice, even a simple hammer will do the job.
regards,
zp

BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

The guy put the casting in a vice and hit from the side to get the pin out, crack, snap. I would have opened the vice, just wider than the pin flanged end, slightly pinching it, resting the plastic pulley on the vice grips and then used the punch and hammer. Then use the vice to press the new on back on.
I never thought the metal would crack/snap, but do now, which i knew before. Crying or Very sad

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BigAl · P4 Joined: 06 May 2003 Posts: 2990 Location: U.K Surrey

still waiting on my bits Crying or Very sad

I have been reading up on torque settings and am confused as the micro's have 2 different values

page 681 for head bolt pattern and torque 97 Nm

page 704 for head bolt torque 67NM with 300mm wrench 73Nm with 400mm wrench

If i remember correctly the 8v was 63Nm, what is correct for the 16v?
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