Strange Head problem

16th August 2011, 20:25

Right well last night I went to start the VTR and it was chucking out white smoke from the exhaust and running rough. Checked the oil - creamy coffee mayo, so wasnt very happy. Tonight I pulled the head off and was presented with a strange issue as the head gasket seems fine and doesnt appear damaged. Both the block face and the head face have had a straight metal ruler on them and nothing seems bent or warped from what I can tell. As you can see bore 3 has been washed rather badly, so this tells me this engine was obviously run for a while like this I'd assume? The minute I ran it for couldnt have been enough to wash the piston like that surely, see below

Where could this water have got into the cylinder from? I'm going to grind in the valves again and do the valve steam seals. Should I have the head pressure tested and refaced? Everything seems straight and I can see no obvious cracks and as the engine didnt really get hot I doubt a crack would have opened up. Can I get peoples thoughts or suggestions?

ta

Andy

16th August 2011, 20:28

A cracked head isn`t always obvious,as you have said & I agree a pressure test would be a good idea,then if that`s ok get the head skimmed & build it all back up.

16th August 2011, 20:30

Always worth having it checkd by a machine shop just to make sure.

16th August 2011, 20:50

Would you reckon its been going on for some time with that amount of piston washing having happened?

16th August 2011, 20:55

Could be cracked cylinder?

16th August 2011, 20:56

The corner of gasket near your hand doesn't look great too

16th August 2011, 20:56

looks like its had more then a minutes worth of running as well tbh

16th August 2011, 21:00

Quote:

Originally Posted by raunchz

The corner of gasket near your hand doesn't look great too

Is that bit just an oil way? Its no where near cylinder 3 either as the others were sound

16th August 2011, 21:01

Quote:

Originally Posted by mandyslover70

looks like its had more then a minutes worth of running as well tbh

How do you mean? Do you think its been run like this by the previous owner for that amount of washing? Its been run by me for literally a minute or so as it wouldnt run correctly due to the amount of coolant in the bore

16th August 2011, 21:13

Going by the fact its been leaking into the bore and the oil galleries, it was either not torqued down correctly or a warped head imo.

Id skim the head, fit a new gasket and torque it down correctly.

Btw, its cylinder 2, PSA number their engines from the fly end. Just to avoid confusion.

16th August 2011, 21:17

Gab - its not just PSA that label their pistons from the transmission end, it is very commin practice.

I would also recommend a pressure test on the cylinder head just to avoid any disappointment on refitting the head.

16th August 2011, 21:19

Gasket didnt look too old to be fair. What are the tolerances on the 8v head as I've got some feeler gauges here a steel rule so can just give it a quick once over just to see. I think theres a machine shop round here I can get it resurfaced at if need be.
How much does a pressure test cost? Last time I got a head resurfeced I think it was £40 but I didnt have it pressure tested
Do you think lifting the engine in using the lifting eyes on the head might have shifted the head?

16th August 2011, 21:23

I think the general flatness tolerance in a cylinder head fire face is less than 0.1mm. It is always a good practice to brush over it with a mill and rub it down with a stone each time its come off as long as you take the bare minimum off possible.

Different places charge different amounts for a pressure test. Last time I had a quote I think it was £80 for a pressure test and a skim. But its best to ask around.

16th August 2011, 21:45

I'll do that I think. If i take it to the local machine shop they assess it better than I can do.
Whats the head torque sequence - 20nm and then 120 degrees each and then another 120?

16th August 2011, 22:36

I had a similar problem on my Punto.

I took the head off, replaced the h/g and still had the problem. It was using a fair bit of oil and a little water (A table spoon ever 2/ 3 months) I put it down to worn out piston rings/ age of car.

Though the gasket seemed fine, it had just the tiniest little nick by piston #2. Couldn't see it unless you knew where it was and what you were looking for.

16th August 2011, 23:00

Quote:

Originally Posted by logic_guy

I had a similar problem on my Punto.

I took the head off, replaced the h/g and still had the problem. It was using a fair bit of oil and a little water (A table spoon ever 2/ 3 months) I put it down to worn out piston rings/ age of car.

Though the gasket seemed fine, it had just the tiniest little nick by piston #2. Couldn't see it unless you knew where it was and what you were looking for.

You say the new gasket did it as well? so two duff head gaskets or bore/head problems?

16th August 2011, 23:52

'Right well last night I went to start the VTR and it was chucking out white smoke from the exhaust and running rough'

for it to chuck out white smoke after a minuite of running i reckon that the gaskets started to go the last time it was running which would have caused the clean piston and bore. (smoke may not have been as noticeable then if atall ?) would definatly recommend a pressure test though! even though theres nothing noticable you may find something or even just for peace of mind.

17th August 2011, 00:03

Yeah thats what i think has happened, its been washed when running before. I mean its only had coolant in it for 2 days I doubt that if any got on the piston it'd look as shiny as it does in that timeframe. I think manhandling it about when it got delivered, dangling on a crane for the install etc may have disturbed it a little more which has shown up when I started it.

17th August 2011, 00:21

Quote:

Originally Posted by Gandi699

You say the new gasket did it as well? so two duff head gaskets or bore/head problems?

My guess was head/ bore problem. Engine had done around 130K lol, previous owner didn't treat it to a service once while he had it lol. (I only bought it cheap as a run around)

17th August 2011, 09:35

answer is simple
the gasket fitted is very old stylegasket --kevlar+ fire rings .
citroen stopped using these type of gaskets on all cast iron block engines 10 years ago .
you should get the head checked for distortion ,then fit an MLS type gasket + new bolts
end of problem .
alot of motor factors still supply these types of gaskets as a replacment --do not use them
you notice the rust colour in the water ways --that shows anti freeze has lost its anti corrosion qualities ,as all coolant does over a period of time .
the leak will be a split in the fire ring and corrsion in the kevlar gasket allowing water to seep into the bore

17th August 2011, 09:40

Quote:

Originally Posted by axsaxoman

answer is simple
the gasket fitted is very old stylegasket --kevlar+ fire rings .
citroen stopped using these type of gaskets on all cast iron block engines 10 years ago .
you should get the head checked for distortion ,then fit an MLS type gasket + new bolts
end of problem .
alot of motor factors still supply these types of gaskets as a replacment --do not use them
you notice the rust colour in the water ways --that shows anti freeze has lost its anti corrosion qualities ,as all coolant does over a period of time .
the leak will be a split in the fire ring and corrsion in the kevlar gasket allowing water to seep into the bore

Nice bit of info there mate cheers, MLS gasket is on the way as we speak. The head appears good and flat but is it worth having it resurfaced anyway?

17th August 2011, 09:43

if using std cam then can take at 1mm of it --that will give you a bit more punch as well

17th August 2011, 10:41

Its an XSi engine so I believe it runs higher compression pistons and 270 degree cam compared to standard vtr 8v. Still viable to the 1mm skim or should I just leave it if its flat?

27th August 2011, 00:35

Right i've fitted an FAI multi layer gasket and had the head refaced and a I get piston and valve contact?! If I slacken off the valve clearances it will turn but the compression is very very high also impossible to turn by hand. Can I get a thicker gasket and do you reckon the machine shop have skimmed far too much off!?!

27th August 2011, 07:19

How much did they take off?

axsaxomans advice of taking 1mm off is very very poor. Since this piece of advice made the assumptions that it was a standard engine which had never had the head skimmed in the past. You should have asked the machine shop to take as little off as possible to avoid potential piston contact and so in the future the head can be skimmed again without it being scrapped. Upping the compression without changing the calibration puts the engine at risk of detonation too.

You need to measure your valve clearances from 15 degrees BTDC to 15 degrees ATDC and from that you will be able to work out if you can get away with a thicker H/G or a new head will be required.