I’m looking for technical help or recommendations on: __ post head gasket and cyl head work
Just replaced a blown headgasket and cracked rad on my 96 Mk1 1.8… ,this has reduced but not completely got rid of the amount of white smoke from the exhaust. car was driving normal (considering the blown headgasket) before the gasket replacement.
After replacing the headgasket car starts and idles perfectly, coolant system bled completely, oil + filter, all seals, cam belt, thermostat and coolant overflow all replaced and filled to correct level, no leaks.
PROBLEM is now when trying to drive feels like there is a reduction power… not a huge amount, just as I pull through the gears (2nd to 4th). Feels as if somthing is holding the car back. and there is still white smoke from the exhaust, doesnt have that “sweet coolant smell” but doesnt smell like oil either… thought it might have been excess in the cylinders and exhaust system but after a 3 min drive around the block car is still producing some white smoke from tail pipe. This does reduce further after a drive. I’ve only had it bad for a day and the garage who did the work did say to give it 2-3 weeks of ‘gentle’ driving to let it bed in. Is this to be expected?
Cyl head was cleaned, skimmed by 0.006, new exhaust guilds, valves reset, hydraulic tappets evacuated - car never overheated and doesnt overheat currently, coolant level is still the same, replaced spark plugs, new 8.5 ig leads as well with the head gasket.
Head bolts were removed and installed in correct order as well as properly torqued, Timing is set perfectly with no idle or reving problems. cant figure out why i still have persistant by less white smoke out of the exhaust??
my next step is going to compression test the cylinders and pressure test the coolant system MY MAIN QUESTION IS why do I have slightly power when in gear?
The trans fluid level and quality is good. HAS ANYONE EXPERIENCED THIS PROBLEM BEFORE?? Any help is greatly appreciated,
That’s a very good point. Interestingly I took her for another run this morning shortly after I posted this and the white smoke has reduced further still… plus there is less water (vapour) collecting at the tip of the exit pipe… will see if that stays as it should after a few more runs.
In terms of the hesitancy or slight lack of power, the pull seems to be a tad better too… I’m wondering if I need to get the ignition timing or crack timing adjusted as well
As mk375 says If you’ve been pumping coolant in to the exhaust for a while the exhaust baffles are probably saturated with it. It’ll steam away with some proper use
If the power deficit is that noticeable it may be worth checking the cam timing is correct after the belt change. It’s surprisingly easy to get one or the other cams a tooth out.
A possibility if you have not in the time of owning the car had the ignition timing set, is that it was advanced to 14 degrees a common mod to do and In my opinion is a night and day difference.
Could also be that the correct procedure to set timing was not followed, bridging the diagnostic pin ten to ground to lock timing to ten degrees.
There may be evidence of previous work for example, marks to assist retiming on the cas and head.
So it’s been a few months since I posted and had the issue above… so… the white smoke as subsided by quite some margin, especially after about 20mins or so of driving…
However, the problem now seems to be with the tappets… they are pretty loud especially after motorway driving at 70/80mph - They seem to quieten after driving at lower speeds however. But the sound comes back… the ‘tapping’ sound is definitely just under the rocker cover but also feels/sounds like it’s coming from deeper in the lower head/block.
I’m thinking the garage put the wrong type of oil in maybe? Perhaps an oil and filter change and perhaps a new oxygen sensor. I’m also considering a new manifold and cat replacement as a separate idea or next phase.
It maybe they used a rubbish quality oil, 10/40 or otherwise, that loses viscosity at the normal operating temperature of around 100c, which would only be reached after 20 minutes or so. (The water temperature will come up much more quickly than this)
As a starting point I’d change the oil for a good quality 0 or 5/40 (‘0’ oils are made from better quality base stock than ‘5’) and see if it makes any difference…
Losing power at the same time as the noise occurring could be the valve timing being affected by the hydraulic lifters not pumping up enough so the cam rotates too far before actually doing anything (hence the ticking) and the valves not achieving full lift. It would have to be pretty bad though.
Where is the oil feed to the head? Could it be partially blocked after hg change?
Sooo, update… Thank you for the ‘0’ suggestion… it’s worked a treat!
I think the fact the after a head gasket change and the fact she probably needed new oil, the FS oil was just what was needed. The rev range also seems more ‘free’ whilst the engine sounds and feels smooth.
Tappet sound has gone completely after driving at 70mph and for more than 20 minutes… even on start up, I can’t hear the tappets… except for perhaps 1 or 2 start-ups out of 10 and even then, you hear them faintly for about a second. I suspect that’s because some residue of the older oil still in the engine and with another ‘0’ FS oil change this will go completely.
Full engine rebuild this winter along with the Diff and gearbox which I’m hoping will get rid of the rather strange running sound I get at the rear at 40/50mph.
