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Discussion Starter · #1 ·
Onwards and upwards....., we had hoped to finish installing the Alfetta head today but couldn't join the cam chain because the tensioner wouldn't slide any further in to its hole, we used as much force as we dared but it felt like it was coming up against a stop, it moves in and out quite freely so isn't jammed and the locking bolt works fine The tensioner was from the original head which we transferred to the new head so questions are

Is it possible the tensioner is different between heads?
Do we need to use a lot of force to get it to get it to retract, like jemmy type force?
Would getting the large hex plug out of the head to have a closer look be worth doing?
And finally any ideas why the bleeding thing wont slide all the way into the hole, its about 15mm proud.

I'll post some pics but cant at the mo cos I need to get rid of some first
Thanks
 

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How are you trying to push it back in, I used a long piece of wood against the cog to lever it back in then tightened the bolt, it wasn't difficult to do though and didn't need much force but I couldn't have done it by hand.
 

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Discussion Starter · #3 ·
Length of hikory but its nowhere near strong enough, sounds like there must be a restriction
 

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fully retracted it is flush, like here:
https://www.alfabb.com/bb/forums/1265817-post17.html

with the tensioner bolt tight-ish, does it still show a thread or two? (bolt head should not be flush with the head, if it is it has been overtightened or the wedge has been either not located or forgotten)

as you swopped over tensioners, did you remember to locate the wedge so the pin on the bolt locates into it?
pic here shows wedge:
https://www.alfabb.com/bb/forums/1265666-post13.html

what can happen is the little wedge dislodges. tensioner bolt has a pin on the end that fits into a hole on the taper....when the pin is not located the wedge gets pushed back....you should only undo the bolt by a half to 3/4 turn when adjusting tensioner.

removing the large hex you see inside...here the spring is out and you can see the wedge (here in correct position)
https://www.alfabb.com/bb/forums/1269201-post28.html

no solution, but a few things to think about:)

the tensioner has some force behind it....if it moves smooth but stops 1.5 cms before it retracts fully, there is something jammed (can also be scuffing inside the bore, where the tensioner fits....ideally should've checked the tensioner retracts fully before fitting the head;))
 

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Discussion Starter · #5 ·
Thanks Dom, it was located OK but I have a feeling I undid the bolt too much and the wedge is now stuck behind the tensioner, bloody DOHC's!, I'm going back to my pushrods...
 

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Discussion Starter · #6 ·
Think we will have to take the head off to be sure to locate the tensioner at its most compressed and lock it off before putting the head back on, live and learn
 

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Discussion Starter · #7 ·
Right - we sorted it today - unscrewed the hex plug behind the tensioner and there was the locking wedge lying in the tensioner hole so pushed that back into the slot, located it by eye with the locking bolt and pushed the tensioner back into the head , then released the tensioner a bit and managed to screw the hex plug back into the head - took two of us because we had to push against the spring. next thing we couldn't get the link into the chain because the ends weren't close enough until we realised the crank had moved slightly and the marks weren't lining up any more, once all the marks were lined up properly the link went in and bingo -cam chain back on, now for all the fiddly nuts and bolts on the exhaust and inlet....
 

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Been following this with interest. I’ve given my 1750 Engine a full overhaul and put the head back on now. My tensioner screw is also hard up against the block. I know I didn’t slide the wedge in when I put the spring and tensioner sprocket back in, but I perhaps wrongly assumed it was still in.
It did seem to function correctly, but I’m going to have to take the cover off, split the chain and pull it out to check. ):

Just hope I don’t need to take the hard back off.
 

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Discussion Starter · #9 · (Edited)
Been following this with interest. I’ve given my 1750 Engine a full overhaul and put the head back on now. My tensioner screw is also hard up against the block. I know I didn’t slide the wedge in when I put the spring and tensioner sprocket back in, but I perhaps wrongly assumed it was still in.
It did seem to function correctly, but I’m going to have to take the cover off, split the chain and pull it out to check. ):

Just hope I don’t need to take the hard back off.
Sounds like the wedge has gone walkies...., the bolt will still function as a locking bolt without the wedge as we found out but it could be disastrous if the tensioner slips and the chain jumps, if your bolt is hard up against the head the wedge is definitely missing, rather than removing all the clobber its much easier to undo (shouldn't take too much force) the hex nut behind the tensioner and see if the wedge is there, if not you'll need to find it before you start the engine...... again its much easier to slide the wedge into place with the hex nut out, but you'll need someone to hold the nut in place as you screw it back in because of the spring tension, rather that than dropping the wedge into the cam chain cavity
When undoing the hex don't forget the spring will be acting against it so take care
 

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Ok it’s not in the engine I know that much.
I’ve ordered a new wedge so will work out how to fit it. I’ve become pretty adept at fixing things by myself, don’t have many helpers locally. I try not to trouble the Mrs, she’s still not forgotten when I had her holding the rear axle up when I swapped to an LSD!.
 

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Discussion Starter · #11 ·
That's good then - if you do take the hex out you'll be able to locate the wedge (it only fits one way) correctly pretty easily by finger and then eyeing it down the locking bolt hole until its lined up, if you let the tensioner out as far as possible there wont be so much pressure from the spring when your doing the hex back up; you wont need to split the chain if you do it this way
 

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Ok so are you saying there should be a big enough gap between the casting and the tensioner sprocket to fit the wedge in and push it upwards towards the screw hole?

I’ve not checked, but I didn’t think I’d be able to do that, I was expecting to split the chain and take the whole tensioner out again.
 

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Discussion Starter · #13 ·
It difficult to explain but if you undo and remove the hex plug you will be able to slide the wedge into position on the tensioner shaft from behind with your finger, then look through the tensioner locking bolt hole and make sure the hole in the wedge lines up centre and do the locking bolt up, the wedge should then be located on the little "prong" on the end of the bolt, then you can screw the hex plug back in (with help). that way you don't have to split the chain or remove the tensioner
Other way is to split the chain and then slide the wedge and tensioner back into the hole complete with the wedge but there is a risk of dropping the wedge into the abyss unless you grease it up really well, have a look at Dom's links on this thread, its a bit clearer.
 

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Thanks Dom, it was located OK but I have a feeling I undid the bolt too much and the wedge is now stuck behind the tensioner, bloody DOHC's!, I'm going back to my pushrods...
What mate! With that mentality, it is clear you should never have left push rod engines behind. The twin cam Alfa is classic, not just because of it's specific output power as a bogo production engine, but because of it's simplicity. There would not be so many nerds driving around in Bertone GTA's if it actually required any real understanding.

Now trying to balance a pair of Delorto's may well be a bit of a challenge - but a lock - nut, a spring and a sprocket? Do me a favour - forget the shank of a hammer and just give it a full on "Clout with the head - that's the metally bit at the end of the shank!:jester::jester::jester::jester::jester::jester::jester:
 

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Discussion Starter · #15 ·
What mate! With that mentality, it is clear you should never have left push rod engines behind. The twin cam Alfa is classic, not just because of it's specific output power as a bogo production engine, but because of it's simplicity. There would not be so many nerds driving around in Bertone GTA's if it actually required any real understanding.

Now trying to balance a pair of Delorto's may well be a bit of a challenge - but a lock - nut, a spring and a sprocket? Do me a favour - forget the shank of a hammer and just give it a full on "Clout with the head - that's the metally bit at the end of the shank!:jester::jester::jester::jester::jester::jester::jester:
I'm assuming you're taking the ****....
 

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Well that went as I expected.... badly!. After waiting a week for a new wedge to arrive ( stuck in the post I think).
I took the hex bolt out and sure enough, no wedge in, but not only that the little plug was missing off the bolt and the end of it chewed up quite badly, enough to damage part of the thread in the head. Fortunately I had a spare in my ‘ parts’ engine ( which interestingly had no wedge either!.
There was no way I could get the new wedge in working from above, with or without the chain split.
So it was a head off job, it wasn’t too bad getting wedge into place from the underside, that bit went Ok, replacing the head gave me an opportunity to put a small run of sealant at the back of the head, something I found was good practice, a day after I’d fitted the head previously.

Then putting the cam chain back together the bloody link jumped out, managed to find a hole I hadn’t plugged and fell into the engine.

I did have a spare, so completed the task, but I’m going to have to lift the motor up again now and take the sump pan off to retrieve it!.

Grrrrrr :(
 

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Nightmare, that is bad luck. Must be worth having a fish around with one of those magnets on a stick things before taking the sump off.
 

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Nightmare, that is bad luck. Must be worth having a fish around with one of those magnets on a stick things before taking the sump off.
I'd check with an endoscope, fairly cheap nowadays....I use a Depstech Wifi endoscope which is viewed on the iphone or pad and with a long rigid but bendable stalk. the stalk can be up to 5 meters, so you could probably go right down into the sump and back out the exhaust:);)
As its wifi, there is no cumbersome handle or anything, basically just a long bendy stick with an on/off switch on the end.

Oh, and be very sure the link has not lodged between chain and idler gear......if it is and you start the engine, something will break.
 

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Discussion Starter · #20 ·
Ah! - bummer, all the bad bits in one go.
 
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