36 replies to this topic

[Sutol]

Perhaps get your oil tested to check for excessive wear

[fezzasus]

Perhaps get your oil tested to check for excessive wear

won't show anything useful; too many sources of iron to confirm anything.

I would be interested in the condition of the bearings though, so the copper might be interesting

[fezzasus]

As others have said, I think thats normal wear for an engine of your milage. If you blue-printed/measured the actual wear from OEM spec I would be surprised if it was more than 0.1 mm, which is trifling really. For example you piston rings will probably accomodate several times that amount of wear without issue.

These arn't piston rings, and you certainly can't base the wear of the piston rings on the wear of the tappets and cam.

As I said, it's not the ultimate wear that's occured, it's the pitting that is a big concern.

[JG]

nah, thats not really a problem.

I've seen properly broken ends like this go on and on.


Might be a good idea to change them, but neither the pitting. not the scoring is an indication of engine wear/viability.

[fezzasus]

nah, thats not really a problem.

I've seen properly broken ends like this go on and on.


Might be a good idea to change them, but neither the pitting. not the scoring is an indication of engine wear/viability.

It certainly is an indication, it's my job to rate engine performance of engine oils.

BTW, that's more than pitting on the vw tdi cam, it looks like a hardware defect given the cratering in the middle of the lobe.

Edited by fezzasus, 14 April 2012 - 08:11 AM.

[Sutol]

Perhaps get your oil tested to check for excessive wear

won't show anything useful; too many sources of iron to confirm anything.

I would be interested in the condition of the bearings though, so the copper might be interesting

yes but surely it will show up as excessive, depending on when you changed your oil.

[JG]

i'm not doubting your credentials Fezza, but in my experience (and i've also worked in tribology labs) it is a factor or many other things. Engine design, usage, types of lubrication etc etc. So much so, there were plenty of example of engines with worn out bottom ends and perfectly normal top end and visa versa including everything in between.

[fezzasus]

i'm not doubting your credentials Fezza, but in my experience (and i've also worked in tribology labs) it is a factor or many other things. Engine design, usage, types of lubrication etc etc. So much so, there were plenty of example of engines with worn out bottom ends and perfectly normal top end and visa versa including everything in between.

Of course, and service history doesn't reflect how car car has been treated. This is another reason I want to put a new engine in it, from what I can tell from removing the rocker cover I can make the following assumptions:

1. The cams have rust on them, this is either due to the oil leak causing them to run dry, or through long periods of no use.

2. There is scoring on all cams, this indicates debris entrainment

3. There is pitting on 3 inlet and 1 outlet cams - this will produce more wear debris as it progresses

4. There is a high degree of varnishing on the rocker cover. This is a thick varnish that doesn't remove easily. While it's medium temperature varnish so doesn't form through the same mode, it does suggest that the pistons won't be in a great condition which will lead to ring stick and excessive ring wear.

Bearing wear is unlikely on a VX - it just doesn't have high load, low rpm situations which cause it.

[JG]

and indeed sticking a new engine in it will be a lot of fun, and that's the real reason for doing it

[fezzasus]

Perhaps get your oil tested to check for excessive wear

won't show anything useful; too many sources of iron to confirm anything.

I would be interested in the condition of the bearings though, so the copper might be interesting

yes but surely it will show up as excessive, depending on when you changed your oil.

it's only useful if i've been sampling the oil for most of the life of the engine - you need to establish a baselines of acceptable wear metal measurements before you identify any increase. It does vary from engine to engine and from oil to oil - although most variations depend on the quality of manufacture. large US engines see 100 ppm iron measurements during typical operation because the quality of finishing is low, most european engines see less than 10 - but this is a guide only. I'd need more data on the Z22SE to gain anything from it.

[fezzasus]

and indeed sticking a new engine in it will be a lot of fun, and that's the real reason for doing it

It's certainly something i've been mulling over up to now, but the general condition of this engine as reinforced the idea, especially because I intend on keeping my VX for a while. I'd be quite happy to build up at B207 based engine while continuing to run the Z22SE while is why i'd like to gather some info now.

[vocky]

I have seen similar damage after the engine has been run momentarily low on oil, like on some track corners where the oil light comes on. Also if the oil restrictor in the head gets blocked by debris you can get similar damage, again due to oil starvation. As others have said, it should last for a while but it would be good practice to rebuild / build another engine if you intend keeping your car for a long time.

[fezzasus]

I have seen similar damage after the engine has been run momentarily low on oil, like on some track corners where the oil light comes on.

Also if the oil restrictor in the head gets blocked by debris you can get similar damage, again due to oil starvation.

As others have said, it should last for a while but it would be good practice to rebuild / build another engine if you intend keeping your car for a long time.

cheers Vocky.

Am I right in thinking I should be aiming for a B207 with a Y22SE crank?

[vocky]

you can modify the B207 to run in the vx, but you will need to use the z22se crank and 2.2 pistons and rods, so a full rebuild would be required to the B207 before fitting. You also need to use z22se cams which require additional components, I can supply those.

[fezzasus]

you can modify the B207 to run in the vx, but you will need to use the z22se crank and 2.2 pistons and rods, so a full rebuild would be required to the B207 before fitting. You also need to use z22se cams which require additional components, I can supply those.

The additional components mainly being a blank for the shorter Z22se exhaust cam?

[Winstar]

you can modify the B207 to run in the vx, but you will need to use the z22se crank and 2.2 pistons and rods, so a full rebuild would be required to the B207 before fitting. You also need to use z22se cams which require additional components, I can supply those.

by which point you've took out most of the better spec components that are fitted and those that are left are overkill for a NAsp engine

[fezzasus]

you can modify the B207 to run in the vx, but you will need to use the z22se crank and 2.2 pistons and rods, so a full rebuild would be required to the B207 before fitting. You also need to use z22se cams which require additional components, I can supply those.

by which point you've took out most of the better spec components that are fitted and those that are left are overkill for a NAsp engine

doesn't mean i'll be keeping it NA