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Discussion Starter #1
Does anyone on here know if there are any crucial differences between the 1.9 jtd cylinder heads?
Reason I ask is that my 159 has at some point swallowed 3 swirl flaps (as in an earlier post)
The car ran mostly OK but the head is pitted in 3 of the 4 cylinders so rather than have this repaired my plan was to fit the head from a spare engine I have.
I have removed the spare engines head and it does look good, I took it down to a mates garage for a second opinion and he said he'd just throw that one on as it does look a good head, no signs of leaking valves or failed head gasket whatsoever.
The only difference I can see us that the holes for the cam cover on the 159 engine are threaded all the way through and the 156 donor engine aren't. Simple solution to that is use the bolts from the 156
The 159 is the 150 bhp model and the 156 was the 140 bhp if that makes any difference.

Thanks in advance for any info / advice
 

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The cf4 159 used slightly thinner stemmed valves than the cf3 and also a different cam belt with 1 tooth less so you will need to use the heads original rockers and incase the cam pulley is different, I dont know if it is, the cars original cam carrier
 

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Discussion Starter #3
Thanks for that, just checked and annoyingly you are spot on. 198 teeth on the 156 belt 199 teeth on the 159 belt. And yes the rockers are different width where the valve goes. I knew the cam followers were slightly different but seemed to be interchangeable and when I googled them for images of replacements for the 156 it showed the type I had in the 159 so just assumed they were a slightly newer version.
I'll dig the cams out and starting pulley teeth on those so assuming I use the 159 engine, the 156 head, 156 rockers and 159 camshafts + housing / carrier or whatever its technical name is ill assume I use the 199 teeth 159 belt.. Does this sound about right or a recipe for disaster?
 

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Discussion Starter #4
That was supposed to say start counting teeth not starting pulling teeth or whatever I put. I'll leave that to the dentists
 

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Discussion Starter #5
Looks like my cheap fix is out of the window! 50 teeth on the 156 cam sprocket and 52 teeth on the 159 cam sprocket.. Bugger
 

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As long as you use the cf4 159 cam carrier and pulley so it matches the original crank pulley you will be ok.
So all the belt system is original and will avoid any incorrect cam belt problems in the future
If the 156 cam pulley is different then the crank pulley will also be.
 

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Discussion Starter #7
Thanks for that, you've no doubt saved me a major headache there, it hadn't occurred to me that they had different belts.
Didn't realise there were that many differences to what is basically the same engine.
 

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As above use 159 cam carrier and the 156 rockers to match valve stems.

when I did mine autolusso warmed me about valve stem differences so assume a 159 could have either fitted aswell.
 

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Discussion Starter #9
So it will definitely work with the 156 head then? I'm in 2 minds now as to fit the better head from the 156 or just to try and regrind the valves in the 159 head and refit that. I didn't bother with the machine shops, I went to a mates garage and he basically said what I expected, they'll just say it needs this that and the other, mainly to cover their own arse. He's had a lot of experience with them and does send a lot of work to them but said in the case of my head if it was his own he'd just clean it up and fit it as there is no signs of anything untoward and the car it came from ran well.
 

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You could always put head on it’s side and fill ports with brake cleaner or paraffin and see if it leaks past the valve seats. Spin head round and do ports on other side. If no leaks you can be pretty confident the valves aren’t bent.
If looks ok I would probably whip the valves out and lap them in again and double check there are no flaps jammed around the guides
 

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Discussion Starter #11
Yeah did that yesterday and nearly all the valves that were in the affected 3 cylinders had slight seepage. I wasn't going to refit that head anyway without stripping it first because like you say there may well be something jammed behind. Just means I'll need to borrow a valve spring compressor as mine won't do the springs that are recessed into the head.
If the other head will be OK then I'll use that, just wondering if anyone has fitted the earlier head before and if there were any problems.
 

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I think if its only a case of removing cleaning and relapping the valves I would stick with the original head.
If you are anywhere near Cardiff I have a valve compressor you can borrow
 

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you can always get some slight leak from valves that have done some miles anyway,how’s the 156 head you done a leak test on that?

If you are near west Wiltshire I am also able to help with loan of a compressor.
Also will be Bristol tomorrow pm if thats any good
 

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Discussion Starter #14
Thanks for the offer, I'm in Blackpool so a bit far away but appreciate it all the same.
I'm going to have to order head bolts now aswell so it's not going back together just yet so probably will end up taking the valves out and having a better look at the original head and then decide which to use.
I read somewhere about the torque settings for reusing the original bolts but can't seem to find it now but everywhere else seems to say new bolts are the way to go.
It's one blooming thing after another!
Should have just fitted a new engine!
 

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Discussion Starter #15
Yeah, the 156 head was good, no leaks on any of the valves.
The 159 did run OK I suppose with its own head, just with all the leaky valves being on the 3 cylinders that swallowed flaps I just thought while it's off its better to replace it with a better head if possible.
 

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Can remove valves without a compressor, just use a deep socket and extension and tap with a hammer. Will need compressor to refit them though
 

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Autodata says to use the bolts a max of 4 times..
Torque is
1. 32-38Nm
2. 62-68Nm
3. 90 degrees
4. 90 degrees
5. 90 degrees
working in the usual pattern from the middle
 

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Discussion Starter #18
Thanks for that, that's good to know I may not need to replace them then.
Do you know if the same settings apply if the bolts aren't in for the first use, I can't find the info I got previously it was in a random Google search but I'm sure the first tightening had a back off step somewhere and the torque settings for a reused bolt was something like 38 +90+90+90
I'll have another search just gotta remember what I typed in!
 

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I looked in to this when I did mine I saw some mention of they can be reused up to 3 times but they need measuring first to make sure after they been removed bolts have relaxed and gone back to original length. As I didn’t want to do it again I opted to replace them for peace of mind.

also the backing off while torquing up was mentioned for the vauxhall z19dth but Alfa specs were tighten in the sequence above with no backing off.

make sure bolt holes have no oil/water/debris in them and don’t oil the threads.
 
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